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Abstract Background Respiratory complications are the most important cause of morbidity and mortality in spinal muscular atrophy (SMA). Respiratory muscle weakness results in impaired cough, recurrent respiratory tract infections and eventually can cause respiratory failure. We assessed longitudinal patterns of respiratory muscle strength in a national cohort of treatment-naïve children and adults with SMA, hypothesizing a continued decline throughout life. Methods We measured maximal expiratory and inspiratory pressure (PEmax and PImax), Sniff Nasal inspiratory pressure (SNIP), peak expiratory flow (PEF), and peak cough flow (PCF) in treatment-naïve patients with SMA. We used mixed-models to analyze natural history patterns. Results We included 2172 measurements of respiratory muscle function from 80 treatment-naïve patients with SMA types 1c-3b. All outcomes were lower in the more severe phenotypes. Significant differences in PEF were present between SMA types from early ages onwards. PEF decline was linear (1–2%/year). PEF reached values below 80% during early childhood in types 1c-2, and during adolescence in type 3a. PEmax and PImax were severely lowered in most patients throughout life, with PEmax values abnormally low (i.e.

Background: Multilevel anterior cervical discectomy and fusion inevitably yields a higher chance of pseudarthrosis or require more reoperations than single-level procedures. Therefore, multilevel cervical disc arthroplasty (CDA) could be an alternative surgery for cervical spondylosis, as it (particularly 3- and 4-level CDA) could preserve more functional motility than single-level disc diseases. This study aimed to investigate the clinical and radiological outcomes of 4-level CDA, a relatively infrequently indicated surgery., Methods: The medical records of consecutive patients who underwent 4-level CDA were retrospectively reviewed. These highly selected patients typically had multilevel disc herniations with mild spondylosis. The inclusion criteria were symptomatic cervical spondylotic myelopathy, radiculopathy, or both, that were medically refractory. The clinical outcomes were assessed. The radiographic outcomes, including global and individual segmental range of motion (ROM) at C3-7, and any complications were also analyzed., Results: Data from a total of 20 patients (mean age: 56 ± 8 years) with an average follow-up of 34 ± 20 months were analyzed. All patients reported improved clinical outcomes compared with that of preoperation, and the ROMs at C3-7 were not only preserved but also trended toward an increase (35 ± 8 vs 37 ± 10 degrees, pre- vs postoperation, P = 0.271) after the 4-level CDA. However, global cervical alignment remained unchanged. There was one permanent C5 radiculopathy, but no other neurological deteriorations or any reoperations occurred., Conclusion: For these rare but unique indications, 4-level CDA yielded clinical improvement and preserved segmental motility with low rates of complications. Four-level CDA is a safe and effective surgery, maintaining the ROM in patients with primarily disc herniations and mild spondylosis., Clinical Relevance: For patients with mild spondylosis, whose degeneration at the cervical spine is not so severe, CDA is more suitable., Competing Interests: Declaration of Conflicting Interests : The authors report no conflicts of interest in this work., (This manuscript is generously published free of charge by ISASS, the International Society for the Advancement of Spine Surgery. Copyright © 2024 ISASS. To see more or order reprints or permissions, see http://ijssurgery.com.)

Cervical synovial cyst (CSC) is a rare condition that often leads patients to seek medical attention due to cervical stenosis symptoms. There's ongoing debate about the best management strategy. To address this, a review of literature from the past 20 years (2003-2023) was conducted using keywords like "cervical synovial cyst," "cervical ganglion cyst," and "cervical juxtafacet cyst." Data on patient demographics, imaging characteristics, treatment methods, and clinical outcomes were collected. A total of 79 patients were diagnosed with CSCs, averaging 62.3 years old, with a slight male predominance (45 males, 34 females). Most cysts were located at the C1-2 and C7-T1 joints, with myelopathy being the most common symptom. Subaxial CSCs had a higher incidence of radiculopathy compared to axial CSCs. Most cases were treated surgically, with decompression performed with or without fusion. Patients generally reported symptom improvement regardless of the surgical method. Overall, surgical intervention effectively improved neurological symptoms associated with CSCs., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

This study aims to evaluate the potential benefits of treating spinal cord injury (SCI) patients with acidic fibroblast growth factor (aFGF), a potent neurotrophic factor that preserves neuronal survival. The study involved 12 tetraplegic patients with American Spinal Injury Association Impairment Scale (AIS) Grade A SCI who were randomly assigned to receive either a recombinant human aFGF or a placebo every 4 weeks for three doses. Participants underwent comprehensive evaluations of medical, neurological, and functional parameters at baseline and every 4 weeks after the first dose until the 48th week. The first dose was administered directly to the injury site during surgery within 6 weeks of the SCI, while the subsequent two doses were administered via lumbar puncture with a 4-week interval. The results revealed promising beneficial effects of aFGF on AIS Grade A SCI patients. The study report highlights aFGF's potential to expedite motor recovery in complete SCI patients and significantly increase the probability of a 10-point improvement when compared to the placebo group (odds ratio = 6.06, p = 0.0004). Furthermore, aFGF treatment exhibited a significant reduction ( p < 0.01) in the incidence or exacerbation rate of myelomalacia, a known secondary complication following SCIs., (© The Author(s) 2024. Published by Mary Ann Liebert, Inc.)

Objective: This study aims to overcome challenges in lumbar spine imaging, particularly lumbar spinal stenosis, by developing an automated segmentation model using advanced techniques. Traditional manual measurement and lesion detection methods are limited by subjectivity and inefficiency. The objective is to create an accurate and automated segmentation model that identifies anatomical structures in lumbar spine magnetic resonance imaging scans., Methods: Leveraging a dataset of 539 lumbar spinal stenosis patients, the study utilizes the residual U-Net for semantic segmentation in sagittal and axial lumbar spine magnetic resonance images. The model, trained to recognize specific tissue categories, employs a geometry algorithm for anatomical structure quantification. Validation metrics, like Intersection over Union (IOU) and Dice coefficients, validate the residual U-Net's segmentation accuracy. A novel rotation matrix approach is introduced for detecting bulging discs, assessing dural sac compression, and measuring yellow ligament thickness., Results: The residual U-Net achieves high precision in segmenting lumbar spine structures, with mean IOU values ranging from 0.82 to 0.93 across various tissue categories and views. The automated quantification system provides measurements for intervertebral disc dimensions, dural sac diameter, yellow ligament thickness, and disc hydration. Consistency between training and testing datasets assures the robustness of automated measurements., Conclusion: Automated lumbar spine segmentation with residual U-Net and deep learning exhibits high precision in identifying anatomical structures, facilitating efficient quantification in lumbar spinal stenosis cases. The introduction of a rotation matrix enhances lesion detection, promising improved diagnostic accuracy, and supporting treatment decisions for lumbar spinal stenosis patients.

Objective: Only a few studies have investigated the gap range of motion (gROM) in cervical myelopathy or deformity caused by ossification of the posterior longitudinal ligament (OPLL). The aim of this study is to investigate the correlation between the individual gROM and the postoperative clinical outcomes of patients with OPLL., Methods: Consecutive patients of cervical myelopathy caused by OPLL were analyzed retrospectively. The clinical outcomes were evaluated using Visual Analogue Scale scores of the neck and arm pain and the Japanese Orthopaedic Association scores. Radiologic measurements included flexion ROM (fROM), which was defined as the difference of cervical lordosis in flexion and neutral positions, extension ROM (eROM), defined as the difference between neutral and extension positions, and gROM, defined as the difference between fROM and eROM. Patients were grouped by the values of gROM, and comparisons of all outcomes were made between the groups., Results: A total of 42 patients underwent surgery. The patients with greater gROM did not differ from those with smaller gROM by demographic characteristics. During follow-up (mean 45.8 months), both groups had similar improvements, but the C5 palsy rates were higher in the greater gROM group than in the smaller gROM group (71% and 22%, P < 0.05)., Conclusions: Simultaneous circumferential decompression and fixation is an effective surgical option for patients with cervical myelopathy caused by OPLL. A higher rate of postoperative C5 palsy was observed in the patients with greater gROMs after surgery, although all patients presented with similar clinical improvements., (Copyright © 2023 Elsevier Inc. All rights reserved.)

1,2-diacetylbenzene (1,2-DAB) is a neurotoxic component of aromatic solvents commonly used in industrial applications that induces neuropathological changes in animals. This study unraveled the toxic impact of 1,2-DAB in nerve tissues, explant cultures, and neuron-glial cultures, and explored whether herbal products can mitigate its toxicity. The effects of DAB on axonal transport were studied in retinal explant cultures grown in a micro-patterned dish. The mitochondrial movement in the axons was captured using time-lapse video recordings. The results showed that 1,2-DAB, but not 1,3-DAB inhibited axonal outgrowth and mitochondrial movement in a dose-dependent manner. The toxicity of 1,2-DAB was further studied in spinal cord tissues and cultures. 1,2-DAB selectively induced modifications of microtubules and neurofilaments in spinal cord tissues. 1,2-DAB also potently induced cell damage in both neuronal and glial cultures. Further, 1,2-DAB-induced cellular ATP depletion precedes cell damage in glial cells. Interestingly, treatment with the herbal products silibinin or silymarin effectively mitigated 1,2-DAB-induced toxicity in spinal cord tissues and neuronal/glial cultures. Collectively, the molecular toxicity of 1,2-DAB in neural tissues involves protein modification, ATP depletion, and axonal transport defects, leading to cell death. Silibinin and silymarin show promising neuroprotective effects against 2-DAB-induced toxicity., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Objective: This prospective randomized study aimed to investigate the accuracy, radiation exposure, and surgical workflow optimization of a novel intraoperative spinal navigation system using preoperative fan-beam (FB) CT versus the classic intraoperative cone-beam (CB) CT in patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF)., Methods: In this two-arm, single-center, randomized study, the authors evaluated the safety and clinical outcomes of a novel navigation system for pedicle screw placement in spine surgery., Results: The accuracy of pedicle screw placement in the experimental group (FB group) was 94.38%, while it was 94.55% in the control group (CB group). Notably, the intraoperative radiation exposure to patients in the FB CT group (mean 0.361 ± 0.261 mSv) was significantly lower than that in the CB CT group (mean 6.526 ± 13.591 mSv) (p < 0.0001). Furthermore, the intraoperative preparation time for screw placement in the FB group (mean 10.6 ± 5.62 minutes) was significantly lower than that in the CB group (mean 17.6 ± 5.59 minutes) (p = 0.0004). No significant differences were observed for blood loss during surgery, total radiation exposure to surgeons, mean time for inserting a single pedicle screw, revision surgery rate, patients' reported outcomes, and length of postoperative hospital stay between the two groups. Significant differences were observed for intraoperative radiation exposure to patients and the preparation time for pedicle screw placement., Conclusions: The preoperative FB CT-based intraoperative spinal navigation system demonstrated comparable accuracy and safety when compared with the intraoperative CB CT-based system. Moreover, the FB CT-based system had a shorter time for screw placement and reduced intraoperative radiation exposure to patients. These findings support the potential benefits of adopting this novel navigation system to enhance surgical precision and reduce radiation-related risks in MIS-TLIF procedures.

Objective: Anterior cervical discectomy and fusion (ACDF) is a standard surgical approach for cervical spondylotic myelopathy (CSM) caused by disc herniations. Although cervical disc arthroplasty (CDA) has become, in the past decade, a viable alternative to ACDF in selected patients, the differences among patients with CSM treated with CDA and ACDF remain elusive. The effectiveness of motion preservation devices in CSM is also unclear., Methods: Adult patients who underwent 1- or 2-level CDA or ACDF between 2007 and 2021 were retrospectively reviewed. Patients whose preoperative T2-weighted MRI demonstrated increased intramedullary signal intensity (IISI) were included and analyzed for the following: comparison of the length of IISI on pre- and postoperative MR images as well as range of motion (ROM) at the indexed levels between the CDA and ACDF groups. Measurement for clinical outcomes included the visual analog scale (VAS) of the arm and neck, the Neck Disability Index, and modified Japanese Orthopaedic Association scores. Perioperative clinical data were also compared between the two groups., Results: A total of 122 patients were allocated to the CDA group and 108 to the ACDF group, with mean follow-ups of 46.6 and 39.0 months, respectively. Patients in the CDA group were younger than those in the ACDF group (47.64 ± 12.40 vs 61.73 ± 12.25 years, p < 0.001) (mean ± SD). The ACDF group had more 2-level surgery compared to the CDA group (p = 0.002). Both groups had significant regression of IISI on postoperative MRI compared to that of preoperative imaging (CDA: 1.23 ± 0.84 to 0.28 ± 0.39 cm; ACDF: 1.07 ± 0.60 to 0.37 ± 0.42 cm; both p < 0.001). The decrease in the length of IISI was similar between the two groups (p = 0.058). The postoperative ROM was well preserved in the CDA group (superior to ACDF, which yielded minimal ROM postoperatively). Both the CDA and ACDF groups demonstrated improvement in Neck Disability Index and modified Japanese Orthopaedic Association scores at 24 months postoperatively. The CDA group had significant improvements on VAS scores, whereas the improvement did not reach significance for the ACDF group at 24 months postoperatively., Conclusions: Significant shortening of IISI on T2-weighted MRI was demonstrated after both CDA and ACDF. At 24 months postoperatively, all clinical outcomes demonstrated improvement after both strategies, except that the VAS score was not significantly improved for ACDF. Therefore, CDA is a safe and effective option for patients with MR-evident CSM.

Intracranial atherosclerotic disease (ICAD) is a major cause of ischemic stroke, especially in Asian populations, which has a high risk of recurrent stroke and cardiovascular comorbidities. The present guidelines aim to provide updated evidence-based recommendations for diagnosis and management of patients with ICAD. Taiwan Stroke Society guideline consensus group developed recommendations for management of patients with ICAD via consensus meetings based on updated evidences. Each proposed class of recommendation and level of evidence was approved by all members of the group. The guidelines cover six topics, including (1) epidemiology and diagnostic evaluation of ICAD, (2) nonpharmacological management of ICAD, (3) medical therapy for symptomatic ICAD, (4) endovascular thrombectomy and rescue therapy for acute ischemic stroke with underlying ICAD, (5) endovascular interventional therapy for postacute symptomatic intracranial arterial stenosis, and (6) surgical treatment of chronic symptomatic intracranial arterial stenosis. Intensive medical treatment including antiplatelet therapy, risk factor control, and life style modification are essential for patients with ICAD., Competing Interests: Conflicts of interest: The authors declare that they have no conflicts of interest related to the subject matter or materials discussed in this article., (Copyright © 2023, the Chinese Medical Association.)

Background: The ossification of the posterior longitudinal ligament (OPLL) is one of the contributing factors leading to severe cervical spondylotic myelopathy (CSM). The mechanism causing ossification is still unclear. The current study was designed to analyze the specimens of patients with or without OPLL., Methods: The study collected 51 patients with cervical spondylosis. There were six serum samples in both the non-OPLL (NOPLL) and OPLL groups. For tissue analysis, there were seven samples in the NOPLL group and five samples in the OPLL group. The specimens of serum and tissue were analyzed by using Human Cytokine Antibody Arrays to differentiate biomarkers between the OPLL and NOPLL groups, as well as between serum and OPLL tissue. Immunohistochemical staining of the ligament tissue was undertaken for both groups., Results: For OPLL vs. NOPLL, the serum leptin levels are higher in the OPLL group, corroborating others' observations that it may serve as a disease marker. In the tissue, angiogenin (ANG), osteopontin (OPN), and osteopro-tegerin (OPG) are higher than they are in the OPLL group ( p < 0.05). For serum vs. OPLL tissue, many chemotactic cytokines demonstrated elevated levels of MIP1 delta, MCP-1, and RANTES in the serum, while many cytokines promoting or regulating bone genesis were up-regulated in tissue (oncostatin M, FGF-9, LIF, osteopontin, osteoprotegerin, TGF-beta2), as well as the factor that inhibits osteoclastogenesis (IL-10), with very few cytokines responsible for osteoclastogenesis. Molecules promoting angiogenesis, including angiotensin, vEGF, and osteoprotegerin, are abundant in the OPLL tissue, which paves the way for robust bone growth.

Traumatic spinal cord injury (SCI) initiates a series of cellular and molecular events that include both primary and secondary injury cascades. This secondary cascade provides opportunities for the delivery of therapeutic intervention. Growth differentiation factor 11 (GDF11), a member of the transforming growth factor-β (TGF-β) superfamily, regulates various biological processes in mammals. The effects of GDF11 in the nervous system were not fully elucidated. Here, we perform extensive in vitro and in vivo studies to unravel the effects of GDF11 on spinal cord after injury. In vitro culture studies showed that GDF11 increased the survival of both neuronal and oligodendroglial cells but decreased microglial cells. In stressed cultures, GDF11 effectively inhibited LPS stimulation and also protected neurons from ischemic damage. Intravenous GDF11 administration to rat after eliciting SCI significantly improved hindlimb functional restoration of SCI rats. Reduced neuronal connectivity was evident at 6 weeks post-injury and these deficits were markedly attenuated by GDF11 treatment. Furthermore, SCI-associated oligodendroglial alteration were more preserved by GDF11 treatment. Taken together, GDF11 infusion via intravenous route to SCI rats is beneficial, facilitating its therapeutic application in the future.

Objective: Although cervical disc arthroplasty (CDA) has reportedly been associated with similarly low incidences of complications to anterior cervical discectomy and fusion, the phenomenon of anterior bone loss (ABL) is unique to CDA and has only recently gained notice. This study thus aimed to investigate the incidence of ABL and its correlation with cervical alignment post-operation., Methods: Consecutive patients who received CDA for herniated disc or spondylosis were retrospectively reviewed. The development and extent of ABL was detected by comparison of preoperative and postoperative serial images for the relative position of the anterior vertebral body with the CDA devices and graded into 3 levels: grade 1 (minor bone loss), grade 2 (anterior portion of the vertebral body without exposure of the artificial disc), and grade 3 (anterior portion of the vertebral body with exposure of the device)., Results: A total of 41 patients were analyzed with a mean follow-up of 24.1 months. Under serial radiologic examinations during follow-up, all patients (41 of 41 = 100%) had bone loss of various degrees, with grade 3 ABL the most common (30 of 41 = 73.1%). There were 8 and 3 patients who had grades 2 and 1 ABL, respectively. The changes of the Cobb angle (ΔCobb) trended towards higher grades of ABL., Conclusions: During the mean follow-up of 2 years, ABL was a common radiologic finding. More than half of the patients (26 of 41, 63.4%) in the series gained cervical lordosis (ΔCobb >0) after CDA. These patients with increased cervical lordosis (ΔCobb >0) after CDA had higher grades of ABL., (Copyright © 2022 Elsevier Inc. All rights reserved.)

Objective: Cervical myelopathy caused by ossification of the posterior longitudinal ligament (OPLL) is not uncommon among Asian ethnic groups. Despite reports comparing the pros and cons of anterior- and posterior-only approaches, the optimal management remains debatable. This study aimed to evaluate the outcomes of patients who underwent a combined anterior and posterior approach, simultaneous circumferential decompression and fixation, for cervical OPLL., Method: The study retrospectively reviewed patients with OPLL and who underwent circumferential decompression and fixation, combined anterior corpectomy and posterior laminectomy. The clinical outcomes were evaluated by the Visual Analog Scale of neck and arm pain, the Japanese Orthopedic Association scores, Neck Disability Index, and Nurick scores at each time-point of evaluation. Radiological evaluations included plain and dynamic radiographs and computed tomography for every patient within 2 years post-operation. Subgroup analyses were further performed between the groups, with and without intra-operative cerebrospinal fluid (CSF) leakage., Results: A total of 41 patients completed the follow-up for more than 2 years (mean = 39.8 months) and were analyzed. Continuous-type OPLL was the most common (44%), followed by segmental (27%), mixed (22%), and localized types (7%) in the cohort. Myelopathy and all other functional outcomes improved significantly at 2 years post-operation (all p < 0.05). There were 13 (32%) patients who had intra-operative CSF leakage. At 2 years post-operation, there were no differences in the demographics, functional outcomes, and complication rates between the CSF-leakage and no-leakage groups. The CSF-leakage group had more patients with continuous-type OPLL than the no-leakage group (77 vs. 29%, p = 0.004 < 0.05). During the follow-up, there was no secondary or revision surgery for pseudomeningocele, pseudarthrosis, or other surgery-related complications., Conclusions: Simultaneous circumferential decompression and fixation combine the surgical benefits of sufficient decompression by the posterior approach and direct decompression of OPLL by the anterior approach. It is an effective surgical option for patients with cervical myelopathy caused by OPLL, given that myelopathy unanimously improved without neurological complications in this study. The fusion rates were high, and reoperation rates were low. Despite higher rates of CSF leakage, there were no related long-term sequelae, and minimal wound complications., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Kuo, Kuo, Chang, Chang, Fay, Wu, Huang, Cheng and Tu.)

Background: Spinal cord injury (SCI) causes a primary injury at the lesion site and triggers a secondary injury and prolonged inflammation. There has been no definitive treatment till now. Promoting angiogenesis is one of the most important strategies for functional recovery after SCI. The omentum, abundant in blood and lymph vessels, possesses the potent ability of tissue regeneration., Methods: The present work examines the efficacy of autologous omentum, either as a flap (with vascular connection intact) or graft (severed vascular connection), on spinal nerve regeneration. After contusive SCI in rats, a thin sheath of omentum was grafted to the injured spinal cord., Results: Omental graft improved behavior scores significantly from the 3rd to 6th week after injury (6th week, 5.5 ± 0.5 vs. 8.6 ± 1.3, p < 0.05). Furthermore, the reduction in cavity and the preservation of class III β-tubulin-positive nerve fibers in the injury area was noted. Next, the free omental flap was transposed to a completely transected SCI in rats through a pre-implanted tunnel. The flap remained vascularized and survived well several weeks after the operation. At 16 weeks post-treatment, SCI rats with omentum flap treatment displayed the preservation of significantly more nerve fibers ( p < 0.05) and a reduced injured cavity, though locomotor scores were similar., Conclusions: Taken together, the findings of this study indicate that treatment with an omental graft or transposition of an omental flap on an injured spinal cord has a positive effect on nerve protection and tissue preservation in SCI rats. The current data highlight the importance of omentum in clinical applications.

Purpose: Most cavernous sinus dural arteriovenous fistulas (CSDAVF) are unilateral; however, simultaneous bilateral CSDAVFs occasionally may be found. This article reports on 141 patients and compares the angioarchitecture and outcomes of embolization of bilateral CSDAVFs with those of unilateral CSDAVFs, with reference to limited demographics (sex and age) of the patients., Method: From January 2010 to February 2018 a total of 141 consecutive patients with CSDAVFs were referred for transvenous embolization. Bilateral CSDAVFs were found in 20 patients (14.2%, with a mean age of 62.2 years). The angioarchitecture of the 141 patients with CSDAVFs were evaluated by conventional cerebral angiography. We compared the angioarchitecture and treatment outcomes of 20 bilateral and 121 unilateral CSDAVFs, and in relation to the patients' sex and age., Results: Female patients significantly dominated the bilateral CSDAVFs (90%, p = 0.043). Bilateral eye symptoms were significantly more common in bilateral CSDAVFs (p = 0.011), with dominant orbital and cavernous symptoms, and showed statistical significance (p = 0.049 and 0.011, respectively). Occlusion of one CSDAVF may significantly decrease the fistula flow of the other untreated side (n = 13, 65%), leading to less coil utilization for embolization in bilateral CSDAVFs (p < 0.001). There was no statistical significance in the occurrence of occlusion of the inferior petrous sinus(s), in pial vein reflux, and treatment outcomes in the unilateral and bilateral CSDAVFs., Conclusion: Bilateral CSDAVFs were more dominant in female patients and frequently presented with orbital and cavernous symptoms. Fewer coils were used per lesion in the bilateral CSDAVFs. There was no statistical significance in bilateral and unilateral CSDAVFs in terms of impact of venous drainage, pial vein reflux and treatment outcomes.

(1) Background: Most of the currently used radiological criteria for craniovertebral junction (CVJ) were developed prior to the popularity of magnetic resonance images (MRIs). This study aimed to evaluate the efficacy of a novel triangular area (TA) calculated on MRIs for pathologies at the CVJ. (2) Methods: A total of 702 consecutive patients were enrolled, grouped into three: (a) Those with pathologies at the CVJ ( n = 129); (b) those with underlying rheumatoid arthritis (RA) but no CVJ abnormalities ( n = 279); and (3) normal (control; n = 294). TA was defined on T2-weighted MRIs by three points: The lowest point of the clivus, the posterior-inferior point of C2, and the most dorsal indentation point at the ventral brain stem. Receiver operating characteristic (ROC) analysis was used to correlate the prognostic value of the TA with myelopathy. Pre- and post-operative TA values were compared for validation. (c) Results: The CVJ-pathology group had the largest mean TA (1.58 ± 0.47 cm 2 ), compared to the RA and control groups (0.96 ± 0.31 and 1.05 ± 0.26, respectively). The ROC analysis calculated the cutoff-point for myelopathy as 1.36 cm 2 with the area under the curve at 0.93. Of the 81 surgical patients, the TA was reduced (1.21 ± 0.37 cm 2 ) at two-years post-operation compared to that at pre-operation (1.67 ± 0.51 cm 2 ). Moreover, intra-operative complete reduction of the abnormalities could further decrease the TA to 1.03 ± 0.39 cm 2 . (4) Conclusions: The TA, a valid measurement to quantify compression at the CVJ and evaluate the efficacy of surgery, averaged 1.05 cm 2 in normal patients, and 1.36 cm 2 could be a cutoff-point for myelopathy and of clinical significance.

Background: Although patients with cervical kyphosis are not ideal candidates for cervical disc arthroplasty (CDA), there is a paucity of data on patients with a straight or slightly lordotic neck., Objective: To correlate cervical lordosis, T1-slope, and clinical outcomes of CDA., Methods: The study retrospectively analyzed 95 patients who underwent 1-level CDA and had 2-yr follow-up. They were divided into a high T1-slope (≥28°) group (HTSG, n = 45) and a low T1-slope (<28°) group (LTSG, n = 50). Cervical spinal alignment parameters, including T1-slope, cervical lordosis (C2-7 Cobb angle), and segmental mobility (range of motion [ROM]) at the indexed level, were compared. The clinical outcomes were also assessed., Results: The mean T1-slope was 28.1 ± 7.0°. After CDA, the pre- and postoperative segmental motility remained similar and cervical lordosis was preserved. All the clinical outcomes improved after CDA. The HTSG were similar to the LTSG in age, sex, segmental mobility, and clinical outcomes. However, the HTSG had higher cervical lordosis than the LTSG. Furthermore, the LTSG had increased cervical lordosis (ΔC2-7 Cobb angle), whereas the HTSG had decreased lordosis after CDA. Patients of the LTSG, who had more improvement in cervical lordosis, had a trend toward increasing segmental mobility at the index level (ΔROM) than the HTSG., Conclusion: In this series, T1-slope correlated well with global cervical lordosis but did not affect the segmental mobility. After CDA, the changes in cervical lordosis correlated with changes in segmental mobility. Therefore, segmental lordosis should be cautiously preserved during CDA as it could determine the mobility of the disc., (Copyright © 2020 by the Congress of Neurological Surgeons.)

Background: The conventional pedicle-screw-based dynamic stabilization process involves dissection of the Wiltse plane to cannulate the pedicles, which cannot be undertaken with minimal surgical invasion. Despite some reports having demonstrated satisfactory outcomes of dynamic stabilization in the management of low-grade spondylolisthesis, the extensive soft tissue dissection involved during pedicle screw insertion substantially compromises the designed rationale of motion (muscular) preservation. The authors report on a novel method for minimally invasive insertion of dynamic screws and a mini case series., Methods: The authors describe innovations for inserting dynamic screws via the cortical bone trajectory (CBT) under spinal navigation. All the detailed surgical procedures and clinical data are demonstrated., Results: A total of four (2 females) patients (mean age 64.75 years) with spinal stenosis at L4-5 were included. By a combination of microscopic decompression and image-guided CBT screw insertion, laminectomy and dynamic screw stabilization were achieved via one small skin incision (less than 3 cm). These patients' back and leg pain improved significantly after the surgery., Conclusion: This innovative dynamic screw stabilization via the CBT involved no discectomy (or removal of sequestrated fragment only), no interbody fusion, and little muscle dissection (not even of the Wiltse plane). As a minimally invasive surgery, CBT appeared to be a viable alternative to the conventional pedicle-screw-based dynamic stabilization approach.

Objective: Cigarette smoking has been known to increase the risk of pseudarthrosis in spinal fusion. However, there is a paucity of data on the effects of smoking in dynamic stabilization following lumbar spine surgery. This study aimed to investigate the clinical outcomes and the incidence of screw loosening among patients who smoked., Methods: Consecutive patients who had lumbar spondylosis, recurrent disc herniations, or low-grade spondylolisthesis that was treated with 1- or 2-level surgical decompression and pedicle screw-based Dynesys dynamic stabilization (DDS) were retrospectively reviewed. Patients who did not complete the minimum 2 years of radiological and clinical evaluations were excluded. All screw loosening was determined by both radiographs and CT scans. Patient-reported outcomes, including visual analog scale (VAS) scores of back and leg pain, Japanese Orthopaedic Association (JOA) scores, and Oswestry Disability Index (ODI), were analyzed. Patients were grouped by smoking versus nonsmoking, and loosening versus intact screws, respectively. All radiological and clinical outcomes were compared between the groups., Results: A total of 306 patients (140 women), with a mean age of 60.2 ± 12.5 years, were analyzed during an average follow-up of 44 months. There were 34 smokers (9 women) and 272 nonsmokers (131 women, 48.2% more than the 26.5% of smokers, p = 0.017). Postoperatively, all the clinical outcomes improved (e.g., VAS back and leg pain, JOA scores, and ODI, all p < 0.001). The overall rate of screw loosening was 23.2% (71 patients), and patients who had loosened screws were older (61.7 ± 9.6 years vs 59.8 ± 13.2 years, p = 0.003) and had higher rates of diabetes mellitus (33.8% vs 21.7%, p = 0.038) than those who had intact DDS screws. Although the patients who smoked had similar clinical improvement (even better VAS scores in their legs, p = 0.038) and a nonsignificantly lower rate of screw loosening (17.7% and 23.9%, p = 0.416), the chances of secondary surgery for adjacent segment disease (ASD) were higher than for the nonsmokers (11.8% vs 1.5%, p < 0.001)., Conclusions: Smoking had no adverse effects on the improvements of clinical outcomes in the pedicle screw-based DDS surgery. For smokers, the rate of screw loosening trended lower (without significance), but the chances of secondary surgery for ASD were higher than for the nonsmoking patients. However, the optimal surgical strategy to stabilize the lumbar spine of smoking patients requires future investigation.

Objective: One- and two-level cervical disc arthroplasty (CDA) has been compared to anterior cervical discectomy and fusion (ACDF) in several large-scale, prospective, randomized trials that have demonstrated similar clinical outcomes. However, whether these results would be similar when treating 3-level disc herniation and/or spondylosis has remained unanswered. This study aimed to investigate the differences between 3-level CDA and ACDF., Methods: A series of 50 patients who underwent 3-level CDA at C3-7 was retrospectively reviewed and compared with another series of 50 patients (age- and sex-matched controls) who underwent ACDF at C3-7. Clinical outcomes were measured using the visual analog scale (VAS) for neck and arm pain, the modified Japanese Orthopaedic Association (mJOA) scale, and the Neck Disability Index (NDI). Radiological outcomes included range of motion (ROM) at the index levels. Every patient was evaluated by CT for the presence of fusion in the ACDF group. Also, complication profiles were investigated., Results: The demographics and levels of distribution in both groups were very similar. During the follow-up period of 24 months, clinical outcomes improved (overall and respectively in each group) for both the CDA and ACDF patients when compared with the patients' preoperative condition. There were essentially few differences between the two groups in terms of neck and arm pain VAS scores, mJOA scores, and NDI scores preoperatively and at 3, 6, 12, and 24 months postoperatively. After the 3-level surgery, the CDA group had an increased mean ROM of approximately 3.4°, at 25.2° ± 8.84°, compared to their preoperative ROM (21.8° ± 7.20°) (p = 0.001), whereas the ACDF group had little mobility (22.8° ± 5.90° before and 1.0° ± 1.28° after surgery; p < 0.001). The mean operative time, estimated blood loss, and complication profiles were similar for both groups., Conclusions: In this selectively matched retrospective study, clinical outcomes after 3-level CDA and ACDF were similar during the 2-year follow-up period. CDA not only successfully preserved but slightly increased the mobility at the 3 index levels. However, the safety and efficacy of 3-level CDA requires more long-term data for validatation.

Background: Overall survival of patients with primary CNS lymphoma (PCNSL) has improved since the introduction of immunochemotherapy. However, up to 10-15% of PCNSL patients still die shortly after diagnosis. In the present study, we aimed to investigate the risk factors of early mortality (death within 60 days after diagnosis) in patients with PCNSL. Methods: We included newly diagnosed PCNSL patients in a tertiary medical center in Taiwan between January 1, 2002 and May 31, 2018. Clinical risk factors were collected and compared between PCNSL patients who had and did not have early mortality. Results: A total of 133 consecutive patients with PCNSL were included in this study. Approximately 9.8% of the PCNSL patients had early mortality. In multivariate analysis, age ≥ 80 (adjusted hazard ratio [HR] 3.34, 95% confidence interval [CI] 1.01-11.04, p = 0.048) and involvement of the basal ganglia (adjusted HR 4.85, 95% CI 1.47-15.95, p = 0.009) were identified as independent risk factors of early mortality. Use of MTX-based chemotherapy served as an independent protective factor for early mortality (adjusted HR 0.19, 95% CI 0.05-0.67, p = 0.010). Infection and tumor-associated mass effect contributed most to early mortality. Conclusion: Early mortality is not uncommon in patients with PCNSL. Identification of patients with higher risk may help clinicians with initiating appropriate surveillance and management., Competing Interests: Competing Interests: The authors have declared that no competing interest exists.

Objective: The published clinical trials of cervical disc arthroplasty (CDA) have unanimously demonstrated the success of preservation of motion (average 7°-9°) at the index level for up to 10 years postoperatively. The inclusion criteria in these trials usually required patients to have evident mobility at the level to be treated (≥ 2° on lateral flexion-extension radiographs) prior to the surgery. Although the mean range of motion (ROM) remained similar after CDA, it was unclear in these trials if patients with less preoperative ROM would have different outcomes than patients with more ROM., Methods: A series of consecutive patients who underwent CDA at the level of C5-6 were followed up and retrospectively reviewed. The indications for surgery were medically refractory cervical radiculopathy, myelopathy, or both, caused by cervical disc herniation or spondylosis. All patients were assigned to 1 of 2 groups: a less-mobile group, which consisted of those patients who had an ROM of ≤ 5° at C5-6 preoperatively, or a more-mobile group, which consisted of patients whose ROM at C5-6 was > 5° preoperatively. Clinical outcomes, including visual analog scale, Neck Disability Index, and Japanese Orthopaedic Association Scale scores, were evaluated at each time point. Radiological outcomes were also assessed., Results: A total of 60 patients who had follow-up for more than 2 years were analyzed. There were 27 patients in the less-mobile group (mean preoperative ROM 3.0°) and 33 in the more-mobile group (mean ROM 11.7°). The 2 groups were similar in demographics, including age, sex, diabetes, and cigarette smoking. Both groups had significant improvements in clinical outcomes, with no significant differences between the 2 groups. However, the radiological evaluations demonstrated remarkable differences. The less-mobile group had a greater increase in ΔROM than the more-mobile group (ΔROM 5.5° vs 0.1°, p = 0.001), though the less-mobile group still had less segmental mobility (ROM 8.5° vs 11.7°, p = 0.04). The rates of complications were similar in both groups., Conclusions: Preoperative segmental mobility did not alter the clinical outcomes of CDA. The preoperatively less-mobile (ROM ≤ 5°) discs had similar clinical improvements and greater increase of segmental mobility (ΔROM), but remained less mobile, than the preoperatively more-mobile (ROM > 5°) discs at 2 years postoperatively.

Background and Purpose: The natural history of flow-related aneurysms after obliteration of brain arteriovenous malformations is poorly understood. The purpose of this study was to evaluate the angioarchitecture and morphologic change in flow-related aneurysms after gamma knife surgery of brain arteriovenous malformations., Materials and Methods: During a 12-year period, 823 patients with brain arteriovenous malformations underwent gamma knife surgery at our institution with complete peritherapeutic angiographic evaluation. From this population, a series of 72 patients (8.8%) with 111 flow-related aneurysms were enrolled (1.5 aneurysms per patient). There were 43 men and 29 women; ages ranged from 18 to 72 years (mean, 43 years). The morphologic change of flow-related aneurysms was longitudinally evaluated before and after obliteration of brain arteriovenous malformations. After gamma knife surgery, angiographic follow-up varied from 26 to 130 months (mean, 58 months)., Results: All flow-related aneurysms were small (mean, 4.1 mm; range, 2-9 mm). There were 72 proximal flow-related aneurysms (mean size, 4.3 mm) and 39 distal flow-related aneurysms (mean size, 3.7 mm). Spontaneous thrombosis occurred more frequently in distal flow-related aneurysms than in proximal flow-related aneurysms ( P < .001). Smaller flow-related aneurysms (<5 mm) tended to spontaneously occlude after obliteration of brain arteriovenous malformations ( P = .036). Two patients had ruptures of proximal flow-related aneurysms at 27- and 54-month follow-ups, respectively., Conclusions: Spontaneous thrombosis occurred more frequently in distal flow-related aneurysms due to occlusion or normalization of distal feeders. Smaller flow-related aneurysms also tended to spontaneously thrombose after obliteration of brain arteriovenous malformations. The rate of flow-related aneurysm rupture in our series was similar to that of natural intradural aneurysms., (© 2019 by American Journal of Neuroradiology.)

Background: This study aimed to investigate whether cervical disc arthroplasty (CDA) would be equally effective in elderly patients as in the young. The inclusion criteria of published clinical trials for CDA-enrolled patients covered the ages from 18 to 78 years. However, there was a paucity of data addressing the differences of outcomes between older and the younger patients., Methods: A series of consecutive patients who underwent one- or two-level CDA were retrospectively reviewed. Patients at the two extreme ends of the age distribution (≥65 and ≤ 40 years) were selected for comparison. Clinical outcome parameters included visual analog scale (VAS) of neck and arm pain, neck disability index (NDI), and Japanese Orthopaedic Association (JOA) scores. Radiographic outcomes included range of motion (ROM) at the indexed level and evaluation of heterotopic ossification (HO) by computed tomography (CT). Complication profiles were also investigated., Results: There were 24 patients in the elderly group (≥65 years old) and 47 patients in the young group (≤40 years old) with an overall mean follow-up of 28.0 ± 21.97 months. The elderly group had more two-level CDA, and thus the mean operative time was longer (239 vs. 179 min, p < 0.05) than the young group. Both groups had similarly significant improvement in clinical outcomes at the final follow-up. All the replaced disc segments remained mobile on post-operative lateral flexion and extension radiographs. However, the elderly group had a slight decrease in mean ROM (- 0.32° ± 3.93°) at the index level after CDA when compared to that of pre-operation. In contrast, the young group had an increase in mean ROM (+ 0.68° ± 3.60°). The complication profiles were not different, though a trend toward dysphagia was noted in the elderly group (p = 0.073). The incidence or severity (grading) of HO was similar between the two groups., Conclusions: During the follow-up of two years, CDA was equally effective for patients over 65 years old and those under 40 years in clinical improvement. Although the elderly group demonstrated a small reduction of mean ROM after CDA, in contrast to the young group which had a small increase, the segmental mobility was well preserved at every indexed level for each group.

Objective: Cigarette smoking can adversely affect bone fusion in patients who undergo anterior cervical discectomy and fusion. However, there is a paucity of data on smoking among patients who have undergone cervical disc arthroplasty (CDA). The present study aimed to compare the clinical and radiological outcomes of smokers to those of nonsmokers following CDA., Methods: The authors retrospectively reviewed the records of consecutive patients who had undergone 1- or 2-level CDA for cervical disc herniation or spondylosis and had a minimum 2-year follow-up. All patients were grouped into a smoking group, which consisted of those who had consumed cigarettes within 6 months prior to the CDA surgery, or a nonsmoking group, which consisted of those who had not consumed cigarettes at all or within 6 months of the CDA. Clinical outcomes were evaluated according to the visual analog scale for neck and arm pain, Neck Disability Index, Japanese Orthopaedic Association Scale, and Nurick Scale at each time point of evaluation. Radiological outcomes were assessed using radiographs and CT for multiple parameters, including segmental range of motion (ROM), neutral lordotic curve, and presence of heterotopic ossification (HO)., Results: A total of 109 patients completed at least 2 years of follow-up and were analyzed (mean follow-up 42.3 months). There were 89 patients in the nonsmoking group and 20 in the smoking group. The latter group was younger and predominantly male (both p < 0.05) compared to the nonsmoking group. The two groups had similar improvements in all clinical outcomes after CDA compared to preoperatively. Radiological evaluations were also very similar between the two groups, except for two factors. The smoking group had well-preserved segmental ROM after CDA at an average of 8.1° (both pre- and postoperation). However, while the nonsmoking group remained mobile, segmental ROM decreased significantly (8.2° to 6.9°, p < 0.05) after CDA. There was a trend toward more HO development in the nonsmoking group than in the smoking group, but the difference was without significance (59.6% vs 50.0%, p = 0.43)., Conclusions: During an average 3.5 years of follow-up after 1- and 2-level CDA, cigarette smokers and nonsmokers had similar improvements in clinical outcomes. Moreover, segmental mobility was slightly better preserved in smokers. Since smoking status did not negatively impact outcomes, CDA may be a reasonable option for selected patients who have smoked., Abbreviations: ACDF = anterior cervical discectomy and fusion; ASD = adjacent-segment degeneration; CDA = cervical disc arthroplasty; FDA = Food and Drug Administration; HO = heterotopic ossification; JOA = Japanese Orthopaedic Association; NDI = Neck Disability Index; ROM = range of motion; VAS = visual analog scale., (© AANS, except where prohibited by US copyright law.)

OBJECTIVEThe pedicle screw-based Dynesys dynamic stabilization (DDS) has reportedly become a surgical option for lumbar spondylosis and spondylolisthesis. However, it is still unclear whether the dynamic construct remains mobile or eventually fuses. The aim of this study was to investigate the incidence of unintended facet arthrodesis after DDS and its association with spondylolisthesis.METHODSThis retrospective study was designed to review 105 consecutive patients with 1- or 2-level lumbar spondylosis who were treated with DDS surgery. The patients were then divided into 2 groups according to preexisting spondylolisthesis or not. All patients underwent laminectomies, foraminotomies, and DDS. The clinical outcomes were measured using visual analog scale (VAS) scores for back and leg pain, Japanese Orthopaedic Association (JOA) scores, and Oswestry Disability Index (ODI) scores. All medical records, including pre- and postoperative radiographs, CT scans, and MR images, were also reviewed and compared.RESULTSA total of 96 patients who completed the postoperative follow-up for more than 30 months were analyzed. The mean age was 64.1 ± 12.9 years, and the mean follow-up duration was 46.3 ± 12.0 months. There were 45 patients in the spondylolisthesis group and 51 patients in the nonspondylolisthesis group. The overall prevalence rate of unintended facet fusion was 52.1% in the series of DDS. Patients with spondylolisthesis were older (67.8 vs 60.8 years, p = 0.007) and had a higher incidence rate of facet arthrodesis (75.6% vs 31.4%, p < 0.001) than patients without spondylolisthesis. Patients who had spondylolisthesis or were older than 65 years were more likely to have facet arthrodesis (OR 6.76 and 4.82, respectively). There were no significant differences in clinical outcomes, including VAS back and leg pain, ODI, and JOA scores between the 2 groups. Furthermore, regardless of whether or not unintended facet arthrodesis occurred, all patients experienced significant improvement (all p < 0.05) in the clinical evaluations.CONCLUSIONSDuring the mean follow-up of almost 4 years, the prevalence of unintended facet arthrodesis was 52.1% in patients who underwent DDS. Although the clinical outcomes were not affected, elderly patients with spondylolisthesis might have a greater chance of facet fusion. This could be a cause of the limited range of motion at the index levels long after DDS.

OBJECTIVETo avoid jeopardizing an aberrant vertebral artery, there are three common options in placing a C2 screw, including pedicle, pars, and translaminar screws. Although biomechanical studies have demonstrated similar strength among these C2 screws in vitro, there are limited clinical data to address their differences in vivo. When different screws were placed in each side, few reports have compared the outcomes. The present study aimed to evaluate these multiple combinations of C2 screws.METHODSConsecutive adult patients who underwent posterior atlantoaxial (AA) fixation were retrospectively reviewed. Every patient uniformly had bilateral C1 lateral mass screws in conjunction with 2 C2 screws (1 C2 screw on each side chosen among the three options: pedicle, pars, or translaminar screws, based on individualized anatomical consideration). These patients were then grouped according to the different combinations of C2 screws for comparison of the outcomes.RESULTSA total of 63 patients were analyzed, with a mean follow-up of 34.3 months. There were five kinds of construct combinations of the C2 screws: 2 pedicle screws (the Ped-Ped group, n = 24), 2 translaminar screws (the La-La group, n = 7), 2 pars screws (the Pars-Pars group, n = 6), 1 pedicle and 1 pars screw (the Ped-Pars group, n = 7), and 1 pedicle and 1 translaminar screw (the Ped-La group, n = 19). The rate of successful fixation in each of the groups was 100%, 57.1%, 100%, 100%, and 78.9% (Ped-Ped, La-La, Par-Par, Ped-Par, and Ped-La, respectively). The patients who had no translaminar screw had a higher rate of success than those who had 1 or 2 translaminar screws (100% vs 73.1%, p = 0.0009). Among the 5 kinds of construct combinations, 2 C2 pedicle screws (the Ped-Ped group) had higher rates of success than 1 C2 pedicle and 1 C2 translaminar screw (the Ped-La group, p = 0.018). Overall, the rate of successful fixation was 87.3% (55/63). There were 7 patients (4 in the Ped-La group and 3 in the La-La group) who lost fixation/reduction, and they all had at least 1 translaminar screw.CONCLUSIONSIn AA fixation, C2 pedicle or pars screws or a combination of both provided very high success rates. Involvement of 1 or 2 C2 translaminar screws in the construct significantly lowered success rates. Therefore, a C2 pars screw is recommended over a translaminar screw.

Objective: The Dynesys-Transition-Optima (DTO) hybrid system was designed to achieve arthrodesis and stabilization in patients with lumbar degeneration. Satisfactory outcomes were demonstrated previously. However, no study has evaluated the effects of using the DTO system in patients with lumbar spondylolisthesis or stenosis., Methods: This retrospective study included 35 consecutive patients with multilevel lumbar degeneration with or without spondylolisthesis who underwent surgery using the DTO system. Imaging studies included pre- and postoperative radiography, magnetic resonance imaging, and computed tomography. The clinical outcomes were measured by Japanese Orthopedic Association (JOA) scores, Oswestry Disability Index (ODI) scores, and a visual analogue scale (VAS) for back and leg pain., Results: Thirty patients (85.7%) with a mean age of 61.9 years completed the follow-up, with a mean duration of 35.1 months. There were 21 patients in the spondylolisthesis group and 9 in the stenosis group. The spondylolisthesis group had worse functional scores than the stenosis group preoperatively. After DTO surgery, all patients showed significant improvements in clinical outcomes, including VAS for back and leg pain, ODI, and JOA scores (p < 0.05). There were no significant differences in clinical outcomes between the 2 groups. At a 2-year follow-up, lumbar alignment was well maintained in both groups (p = 0.116). There were no significant differences in lumbar alignment between the 2 groups., Conclusion: During a follow-up period of over 2 years, both patients with spondylolisthesis and those with stenosis showed improvements and similar disability and pain scores after surgery using the DTO system. Lumbar alignment was also well maintained.

OBJECTIVE Pedicle screw-based dynamic stabilization has been an alternative to conventional lumbar fusion for the surgical management of low-grade spondylolisthesis. However, the true effect of dynamic stabilization on adjacent-segment degeneration (ASD) remains undetermined. Authors of this study aimed to investigate the incidence of ASD and to compare the clinical outcomes of dynamic stabilization and minimally invasive transforaminal lumbar interbody fusion (MI-TLIF). METHODS The records of consecutive patients with Meyerding grade I degenerative spondylolisthesis who had undergone surgical management at L4-5 in the period from 2007 to 2014 were retrospectively reviewed. Patients were divided into two groups according to the surgery performed: Dynesys dynamic stabilization (DDS) group and MI-TLIF group. Pre- and postoperative radiological evaluations, including radiography, CT, and MRI studies, were compared. Adjacent discs were evaluated using 4 radiological parameters: instability (antero- or retrolisthesis), disc degeneration (Pfirrmann classification), endplate degeneration (Modic classification), and range of motion (ROM). Clinical outcomes, measured with the visual analog scale (VAS) for back and leg pain, the Oswestry Disability Index (ODI), and the Japanese Orthopaedic Association (JOA) scores, were also compared. RESULTS A total of 79 patients with L4-5 degenerative spondylolisthesis were included in the analysis. During a mean follow-up of 35.2 months (range 24-89 months), there were 56 patients in the DDS group and 23 in the MI-TLIF group. Prior to surgery, both groups were very similar in demographic, radiological, and clinical data. Postoperation, both groups had similarly significant improvement in clinical outcomes (VAS, ODI, and JOA scores) at each time point of evaluation. There was a lower chance of disc degeneration (Pfirrmann classification) of the adjacent discs in the DDS group than in the MI-TLIF group (17% vs 37%, p = 0.01). However, the DDS and MI-TLIF groups had similar rates of instability (15.2% vs 17.4%, respectively, p = 0.92) and endplate degeneration (1.8% vs 6.5%, p = 0.30) at the cranial (L3-4) and caudal (L5-S1) adjacent levels after surgery. The mean ROM in the cranial and caudal levels was also similar in the two groups. None of the patients required secondary surgery for any ASD (defined by radiological criteria). CONCLUSIONS The clinical improvements after DDS were similar to those following MI-TLIF for L4-5 Meyerding grade I degenerative spondylolisthesis at 3 years postoperation. According to radiological evaluations, there was a lower chance of disc degeneration in the adjacent levels of the patients who had undergone DDS. However, other radiological signs of ASD, including instability, endplate degeneration, and ROM, were similar between the two groups. Although none of the patients in the present series required secondary surgery, a longer follow-up and a larger number of patients would be necessary to corroborate the protective effect of DDS against ASD.

Background: The nonfusion pedicle-screw system Dynesys stabilization (DS) for lumbar degenerative disease aims to better preserve range of motion (ROM) than fixation and fusion systems. However, decreased ROM and unexpected facet fusion at the index level were observed after DS was applied with unknown etiology. The aim of this study is using radiologic parameters to explain the phenomenon of facet arthrodesis., Methods: The patients who underwent surgery for L4-5 spinal stenosis were sorted retrospectively into 2 groups: DS and microdiskectomy (MicD). Radiologic parameters including facet degeneration, evaluated by computed tomography or magnetic resonance image, and ROM, evaluated by dynamic radiographs, were compared perioperatively. A linear regression model was fitted to data points to calculate correlation over time. Postoperative facet arthrodesis at the index level was detected by computed tomography. Functional outcomes were also compared between groups., Results: A total of 61 patients (DS-to-MicD = 38:23) were followed 36.9 ± 16.8 months postoperatively. After surgery, both groups of patients had significant clinical improvement without difference between the 2 groups (all P > 0.05). In the DS group, significantly decreased ROM was observed after 24-month follow-up (P < 0.05). The correlation coefficient of facet degeneration over time and the facet fusion rate in the DS group were both significantly higher than in the MicD group (both P < 0.05)., Conclusions: The patients who underwent DS for L4-5 grade 1 spondylolisthesis experienced significantly reduced ROM and a positive correlation of facet degeneration over time postoperatively. The limited ROM at the index level could be a potential risk of facet degeneration and cause unexpected arthrodesis., (Copyright © 2018 Elsevier Inc. All rights reserved.)

OBJECTIVE Cervical disc arthroplasty (CDA) has been demonstrated to be as safe and effective as anterior cervical discectomy and fusion (ACDF) in the management of 1- and 2-level degenerative disc disease (DDD). However, there has been a lack of data to address the fundamental discrepancy between the two surgeries (CDA vs ACDF), and preservation versus elimination of motion, in the management of cervical myelopathy associated with congenital cervical stenosis (CCS). Although younger patients tend to benefit more from motion preservation, it is uncertain if CCS caused by multilevel DDD can be treated safely with CDA. METHODS Consecutive patients who underwent 3-level anterior cervical discectomy were retrospectively reviewed. Inclusion criteria were age less than 50 years, CCS (Pavlov ratio ≤ 0.82), symptomatic myelopathy correlated with DDD, and stenosis limited to 3 levels of the subaxial cervical (C3-7) spine. Exclusion criteria were ossification of the posterior longitudinal ligament, previous posterior decompression surgery (e.g., laminoplasty or laminectomy), osteoporosis, previous trauma, or other rheumatic diseases that might have caused the cervical myelopathy. All these patients who underwent 3-level discectomy were divided into 2 groups according to the strategies of management: preservation or elimination of motion (the hybrid-CDA group and the ACDF group). The hybrid-CDA group underwent 2-level CDA plus 1-level ACDF, whereas the ACDF group underwent 3-level ACDF. Clinical assessment was measured by the visual analog scales (VAS) for neck and arm pain, Japanese Orthopaedic Association (JOA) scores, and Nurick grades. Radiographic outcomes were measured using dynamic radiographs for evaluation of range of motion (ROM). RESULTS Thirty-seven patients, with a mean (± SD) age of 44.57 ± 5.10 years, were included in the final analysis. There was a male predominance in this series (78.4%, 29 male patients), and the mean follow-up duration was 2.37 ± 1.60 years. There were 20 patients in the hybrid-CDA group, and 17 in the ACDF group. Both groups demonstrated similar clinical improvement at 2 years' follow-up. These patients with 3-level stenosis experienced significant improvement after either type of surgery (hybrid-CDA and ACDF). There were no significant differences between the 2 groups at each of the follow-up visits postoperatively. The preoperative ROM over the operated subaxial levels was similar between both groups (21.9° vs 21.67°; p = 0.94). Postoperatively, the hybrid-CDA group had significantly greater ROM (10.65° vs 2.19°; p < 0.001) than the ACDF group. Complications, adverse events, and reoperations in both groups were similarly low. CONCLUSIONS Hybrid-CDA yielded similar clinical improvement to 3-level ACDF in patients with myelopathy caused by CCS. In this relatively young group of patients, hybrid-CDA demonstrated significantly more ROM than 3-level ACDF without adjacent-segment disease (ASD) at 2 years' follow-up. Therefore, hybrid-CDA appears to be an acceptable option in the management of CCS. The strategy of motion preservation yielded similar improvements of cervical myelopathy to motion elimination (i.e., ACDF) in patients with CCS, while the theoretical benefit of reducing ASD required further validation.

OBJECTIVE Many reports have successfully demonstrated that cervical disc arthroplasty (CDA) can preserve range of motion after 1- or 2-level discectomy. However, few studies have addressed the extent of changes in segmental mobility after CDA or their clinical correlations. METHODS Data from consecutive patients who underwent 1-level CDA were retrospectively reviewed. Indications for surgery were medically intractable degenerative disc disease and spondylosis. Clinical outcomes, including visual analog scale (VAS)-measured neck and arm pain, Neck Disability Index (NDI), and Japanese Orthopaedic Association (JOA) scores, were analyzed. Radiographic outcomes, including C2-7 Cobb angle, the difference between pre- and postoperative C2-7 Cobb angle (ΔC2-7 Cobb angle), sagittal vertical axis (SVA), the difference between pre- and postoperative SVA (ΔSVA), segmental range of motion (ROM), and the difference between pre- and postoperative ROM (ΔROM), were assessed for their association with clinical outcomes. All patients underwent CT scanning, by which the presence and severity of heterotopic ossification (HO) were determined during the follow-up. RESULTS A total of 50 patients (mean age 45.6 ± 9.33 years) underwent a 1-level CDA (Prestige LP disc) and were followed up for a mean duration of 27.7 ± 8.76 months. All clinical outcomes, including VAS, NDI, and JOA scores, improved significantly after surgery. Preoperative and postoperative ROM values were similar (mean 9.5° vs 9.0°, p > 0.05) at each indexed level. The mean changes in segmental mobility (ΔROM) were -0.5° ± 6.13°. Patients with increased segmental mobility after surgery (ΔROM > 0°) had a lower incidence of HO and HO that was less severe (p = 0.048) than those whose ΔROM was < 0°. Segmental mobility (ROM) was significantly lower in patients with higher HO grade (p = 0.012), but it did not affect the clinical outcomes. The preoperative and postoperative C2-7 Cobb angles and SVA remained similar. The postoperative C2-7 Cobb angles, SVA, ΔC2-7 Cobb angles, and ΔSVA were not correlated to clinical outcomes after CDA. CONCLUSIONS Segmental mobility (as reflected by the mean ROM) and overall cervical alignment (i.e., mean SVA and C2-7 Cobb angle) had no significant impact on clinical outcomes after 1-level CDA. Patients with increased segmental mobility (ΔROM > 0°) had significantly less HO and similarly improved clinical outcomes than those with decreased segmental mobility (ΔROM < 0°).

There are many kinds of artificial discs available for cervical disc arthroplasty (CDA), with various designs of fixation and articulation mechanisms. Each of these designs has different features and theoretically fits most optimally in selected types of patients. However, there has been insufficient literature to guide individualized selection among these CDA devices. Since CDA aims to restore the joint function rather than arthrodesis, tailor-made size, shape, and mechanical properties should be taken into account for each candidate's target disc. Despite several large-scale prospective randomized control trials that have demonstrated the effectiveness and durability of CDA for up to 8 years, none of them involved more than one kind of artificial disc. In this video the authors present detailed steps and technical aspects of the newly introduced ProDisc-C Vivo (DePuy Synthes Spine), which has the same ball-and-socket design for controlled, predictable motion as the ProDisc-C. The newly derived teeth fixation provides high primary stability and multilevel capability by avoidance of previous keel-related limitations and complications (e.g., split vertebral fracture). Please note that the ProDisc-C Vivo is currently not available on the US market. The authors present the case of a 53-year-old woman who had symptoms of both radiculopathy and myelopathy caused by a large, calcified disc herniation at C4-5. There was no improvement after 4 months of medical treatment and rehabilitation. A single-level CDA was successfully performed with the ProDisc-C Vivo, and her symptoms were completely ameliorated afterward. The follow-up images demonstrated preservation of motion at the indexed level. The video can be found here: https://youtu.be/4DSES1xgvQU .

The most commonly accepted indications for cervical disc arthroplasty (CDA) are 1- and 2-level cervical disc herniation or spondylosis causing radiculopathy or myelopathy that is refractory to medical management. Unlike anterior cervical discectomy and fusion (ACDF), which eliminates motion, CDA aims to restore the physiological range of motion of the indexed joint. Thus, the effect of indirect decompression gained by the insertion of a sufficiently large interbody graft and incorporation into arthrodesis after ACDF cannot be duplicated for CDA. For patients undergoing CDA, during extreme flexion/extension or rotation, the exiting nerve roots might be impinged by inadequately decompressed foraminal osteophytes. Therefore, the authors advocate generous decompression, including resection of the posterior longitudinal ligament (PLL) and bilateral uncovertebral joints (UVJs), even in the asymptomatic side. This video demonstrates full dural expansion and enlarged neuroforamen after removal of the PLL and UVJs. Venous hemorrhage encountered during foraminotomy can always be controlled by cottonoid packing or hemostatic agents. Also, the endplates of the surrounding vertebral bodies were meticulously prepared for parallel insertion of the ProDisc-C Nova (DePuy Synthes Spine) artificial disc. Please note that the ProDisc-C Nova is currently not available on the US market. The video can be found here: https://youtu.be/XUo34j6WFYs .

Objective: The combination of anterior cervical discectomy and fusion (ACDF) and anterior cervical corpectomy and fusion (ACCF) has been demonstrated to be effective for multilevel cervical spondylotic myelopathy (CSM); however, the combination of ACCF and cervical disc arthroplasty (CDA) for 3-level CSM has never been addressed., Methods: Consecutive patients (>18 years of age) with CSM caused by segmental ossification of posterior longitudinal ligament (OPLL) and degenerative disc disease (DDD) were reviewed. Inclusion criteria were patients who underwent hybrid ACCF and CDA surgery for symptomatic 3-level CSM with OPLL and DDD. Medical and radiologic records were reviewed retrospectively., Results: A total of 15 patients were analyzed with a mean follow-up of 18.1 ± 7.42 months. Every patient had hybrid surgery composed of 1-level ACCF (for segmental-type OPLL causing spinal stenosis) and 1-level CDA at the adjacent level (for DDD causing stenosis). All clinical outcomes, including visual analogue scale of neck and arm pain, Neck Disability Index, Japanese Orthopedic Association scores, and Nurick scores of myelopathy, demonstrated significant improvement at 12 months after surgery. All patients (100%) achieved arthrodesis for the ACCF (instrumented) and preserved mobility for CDA (preoperation 6.2 ± 3.81° vs. postoperation 7.0 ± 4.18°; P = 0.579)., Conclusions: For patients with multilevel CSM caused by segmental OPLL and DDD, the hybrid surgery of ACCF and CDA demonstrated satisfactory clinical and radiologic outcomes. Moreover, although located next to each other, the instrumented ACCF construct and CDA still achieved solid arthrodesis and preserved mobility, respectively. Therefore, hybrid surgery may be a reasonable option for the management of CSM with OPLL., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Objective: Several trials from the U.S. Food and Drug Administration have demonstrated the success of cervical disc arthroplasty (CDA) in patients with degenerative disc disease causing radiculopathy, myelopathy, or both. For patients who had increased intramedullary signal intensity (IISI) on magnetic resonance image (MRI), however, the effectiveness and safety of CDA was unclear. This study aimed to evaluate the outcomes of CDA for patients with IISI on preoperative MRI., Methods: Consecutive patients who received 1-level CDA for symptomatic degenerative disc disease were reviewed retrospectively. Patients with IISI on preoperative T2-weighted MRI were compared to those without IISI (non-IISI). Clinical outcome parameters including visual analog scale, Neck Disability Index, Japanese Orthopedic Association (JOA), and Nurick scores were analyzed. Radiographic studies included dynamic lateral radiography and MRI., Results: A total of 91 patients were analyzed (22 in the IISI group and 69 in the non-IISI group). The mean follow-up was 30.0 months. The demographic data were mostly similar between the 2 groups. All clinical outcomes, including visual analog scale, Neck Disability Index, JOA, and Nurick scores in the IISI group demonstrated significant improvement after operation. The IISI group had similar clinical outcomes to the non-IISI group, except that the JOA scores were generally worse. Follow-up MRI demonstrated significant regression of the length of IISI (P = 0.009). Both groups had preserved motion after CDA., Conclusions: Both clinical and radiological outcomes improved (the average length of IISI in the cervical spinal cord became shorter) after CDA. Therefore, CDA is a safe and effective option for patients even when there is IISI on the preoperative T2-weighted MRI., (Copyright © 2016 Elsevier Inc. All rights reserved.)

OBJECTIVE Several large-scale clinical trials demonstrate the efficacy of 1- and 2-level cervical disc arthroplasty (CDA) for degenerative disc disease (DDD) in the subaxial cervical spine, while other studies reveal that during physiological neck flexion, the C4-5 and C5-6 discs account for more motion than the C3-4 level, causing more DDD. This study aimed to compare the results of CDA at different levels. METHODS After a review of the medical records, 94 consecutive patients who underwent single-level CDA were divided into the C3-4 and non-C3-4 CDA groups (i.e., those including C4-5, C5-6, and C6-7). Clinical outcomes were measured using the visual analog scale for neck and arm pain and by the Japanese Orthopaedic Association scores. Postoperative range of motion (ROM) and heterotopic ossification (HO) were determined by radiography and CT, respectively. RESULTS Eighty-eight patients (93.6%; mean age 45.62 ± 10.91 years), including 41 (46.6%) female patients, underwent a mean follow-up of 4.90 ± 1.13 years. There were 11 patients in the C3-4 CDA group and 77 in the non-C3-4 CDA group. Both groups had significantly improved clinical outcomes at each time point after the surgery. The mean preoperative (7.75° vs 7.03°; p = 0.58) and postoperative (8.18° vs 8.45°; p = 0.59) ROMs were similar in both groups. The C3-4 CDA group had significantly greater prevalence (90.9% vs 58.44%; p = 0.02) and higher severity grades (2.27 ± 0.3 vs 0.97 ± 0.99; p = 0.0001) of HO. CONCLUSIONS Although CDA at C3-4 was infrequent, the improved clinical outcomes of CDA were similar at C3-4 to that in the other subaxial levels of the cervical spine at the approximately 5-year follow-ups. In this Asian population, who had a propensity to have ossification of the posterior longitudinal ligament, there was more HO formation in patients who received CDA at the C3-4 level than in other subaxial levels of the cervical spine. While the type of artificial discs could have confounded the issue, future studies with more patients are required to corroborate the phenomenon.

Object: The aim of this paper was to investigate the risk of recurrence of lumbar disc herniation (LDH) in patients with scoliosis who underwent microdiscectomy., Methods: A series of consecutive patients who underwent microdiscectomy for LDH was retrospectively reviewed. The inclusion criteria were young adults younger than 40 years who received microdiscectomy for symptomatic 1-level LDH. An exclusion criterion was any previous spinal surgery, including fusion or correction of scoliosis. The patients were divided into 2 groups: those with scoliosis and those without scoliosis. The demographic data in the 2 groups were similar. All medical records and clinical and radiological evaluations were reviewed., Results: A total of 58 patients who underwent 1-level microdiscectomy for LDH were analyzed. During the mean follow-up of 24.6 months, 6 patients (10.3%) experienced a recurrence of LDH with variable symptoms. The recurrence rate was significantly higher among the scoliosis group than the nonscoliosis group (33.3% vs. 2.3%, p = 0.001). Furthermore, the recurrence-free interval in the scoliosis group was short., Conclusions: Young adults (< 40 years) with uncorrected scoliosis are at higher risk of recurrent LDH after microdiscectomy.

OBJECT Although anterior odontoidectomy has been widely accepted as a procedure for decompression of the craniovertebral junction (CVJ), postoperative biomechanical instability has not been well addressed. There is a paucity of data on the necessity for and choice of fixation. METHODS The authors conducted a retrospective review of consecutively treated patients with basilar invagination who underwent anterior odontoidectomy and various types of posterior fixation. Posterior fixation included 1 of 3 kinds of constructs: occipitocervical (OC) fusion with atlantoaxial (AA) fixation, OC fusion without AA fixation, or AA-only (without OC) fixation. On the basis of the use or nonuse of AA fixation, these patients were assigned to either the AA group, in which the posterior fixation surgery involved both the atlas and axis simultaneously, regardless of whether the patient underwent OC fusion, or the non-AA group, in which the OC fusion construct spared the atlas, axis, or both. Clinical outcomes and neurological function were compared. Radiological results at each time point (i.e., before and after odontoidectomy and after fixation) were assessed by calculating the triangular area causing ventral indentation of the brainstem in the CVJ. RESULTS Data obtained in 14 consecutively treated patients with basilar invagination were analyzed in this series; the mean follow-up time was 5.75 years. The mean age was 53.58 years; there were 7 males and 7 females. The AA and non-AA groups consisted of 7 patients each. The demographic data of both groups were similar. Overall, there was significant improvement in neurological function after the operation (p = 0.03), and there were no differences in the postoperative Nurick grades between the 2 groups (p = 1.00). According to radiological measurements, significant decompression of the ventral brainstem was achieved stepwise in both groups by anterior odontoidectomy and posterior fixation; the mean ventral triangular area improved from 3.00 ± 0.86 cm 2 to 2.08 ± 0.51 cm 2 to 1.68 ± 0.59 cm 2 (before and after odontoidectomy and after fixation, respectively; p < 0.05). The decompression gained by odontoidectomy (i.e., reduction of the ventral triangular area) was similar in the AA and non-AA groups (0.66 ± 0.42 cm 2 vs 1.17 ± 1.42 cm 2 , respectively; p = 0.38). However, the decompression achieved by posterior fixation was significantly greater in the AA group than in the non-AA group (0.64 ± 0.39 cm 2 vs 0.17 ± 0.16 cm 2 , respectively; p = 0.01). CONCLUSIONS Anterior odontoidectomy alone provides significant decompression at the CVJ. Adjuvant posterior fixation further enhances the extent of decompression after the odontoidectomy. Moreover, posterior fixation that involves AA fixation yields significantly more decompression of the ventral brainstem than OC fusion that spares AA fixation.

OBJECTIVE In the past decade, dynamic stabilization has been an emerging option of surgical treatment for lumbar spondylosis. However, the application of this dynamic construct for mild spondylolisthesis and its clinical outcomes remain uncertain. This study aimed to compare the outcomes of Dynesys dynamic stabilization (DDS) with minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) for the management of single-level spondylolisthesis at L4-5. METHODS This study retrospectively reviewed 91 consecutive patients with Meyerding Grade I spondylolisthesis at L4-5 who were managed with surgery. Patients were divided into 2 groups: DDS and MI-TLIF. The DDS group was composed of patients who underwent standard laminectomy and the DDS system. The MI-TLIF group was composed of patients who underwent MI-TLIF. Clinical outcomes were evaluated by visual analog scale for back and leg pain, Oswestry Disability Index, and Japanese Orthopaedic Association scores at each time point of evaluation. Evaluations included radiographs and CT scans for every patient for 2 years after surgery. RESULTS A total of 86 patients with L4-5 spondylolisthesis completed the follow-up of more than 2 years and were included in the analysis (follow-up rate of 94.5%). There were 64 patients in the DDS group and 22 patients in the MI-TLIF group, and the overall mean follow-up was 32.7 months. Between the 2 groups, there were no differences in demographic data (e.g., age, sex, and body mass index) or preoperative clinical evaluations (e.g., visual analog scale back and leg pain, Oswestry Disability Index, and Japanese Orthopaedic Association scores). The mean estimated blood loss of the MI-TLIF group was lower, whereas the operation time was longer compared with the DDS group (both p < 0.001). For both groups, clinical outcomes were significantly improved at 6, 12, 18, and 24 months after surgery compared with preoperative clinical status. Moreover, there were no differences between the 2 groups in clinical outcomes at each evaluation time point. Radiological evaluations were also similar and the complication rates were equally low in both groups. CONCLUSIONS At 32.7 months postoperation, the clinical and radiological outcomes of DDS were similar to those of MI-TLIF for Grade I degenerative spondylolisthesis at L4-5. DDS might be an alternative to standard arthrodesis in mild lumbar spondylolisthesis. However, unlike fusion, dynamic implants have issues of wearing and loosening in the long term. Thus, the comparable results between the 2 groups in this study require longer follow-up to corroborate.

OBJECTIVE Dynamic stabilization devices are designed to stabilize the spine while preserving some motion. However, there have been reports demonstrating limited motion at the instrumented level of the lumbar spine after Dynesys dynamic stabilization (DDS). The causes of this limited motion and its actual effects on outcomes after DDS remain elusive. In this study, the authors investigate the incidence of unintended facet arthrodesis after DDS and clinical outcomes. METHODS This retrospective study included 80 consecutive patients with 1- or 2-level lumbar spinal stenosis who underwent laminectomy and DDS. All medical records, radiological data, and clinical evaluations were analyzed. Imaging studies included pre- and postoperative radiographs, MR images, and CT scans. Clinical outcomes were measured by a visual analog scale (VAS) for back and leg pain, the Oswestry Disability Index (ODI), and Japanese Orthopaedic Association (JOA) scores. Furthermore, all patients had undergone postoperative CT for the detection of unintended arthrodesis of the facets at the indexed level, and range of motion was measured on standing dynamic radiographs. RESULTS A total of 70 patients (87.5%) with a mean age of 64.0 years completed the minimum 24-month postoperative follow-up (mean duration 29.9 months). Unintended facet arthrodesis at the DDS instrumented level was demonstrated by CT in 38 (54.3%) of the 70 patients. The mean age of patients who had facet arthrodesis was 9.8 years greater than that of the patients who did not (68.3 vs 58.5 years, p = 0.009). There were no significant differences in clinical outcomes, including VAS back and leg pain, ODI, and JOA scores between patients with and without the unintended facet arthrodesis. Furthermore, those patients older than 60 years were more likely to have unintended facet arthrodesis (OR 12.42) and immobile spinal segments (OR 2.96) after DDS. Regardless of whether unintended facet arthrodesis was present or not, clinical evaluations demonstrated improvement in all patients (all p < 0.05). CONCLUSIONS During the follow-up of more than 2 years, unintended facet arthrodesis was demonstrated in 54.3% of the patients who underwent 1- or 2-level DDS. Older patients (age > 60 years) were more likely to have unintended facet arthrodesis and subsequent immobile spinal segments. However, unintended facet arthrodesis did not affect the clinical outcomes during the study period. Further evaluations are needed to clarify the actual significance of this phenomenon.

Background: The efficacy and safety of using cervical arthroplasty for degenerative disc disease have been demonstrated by prospective, randomized and controlled clinical trials. However, there are scant data on using cervical arthroplasty for traumatic disc herniation. Therefore, this study aimed to investigate the outcomes of patients who underwent cervical arthroplasty for traumatic disc herniation., Methods: This cohort included patients who were admitted through the emergency department for trauma. Only patients who had newly-onset, one- or two-level cervical disc disease causing radiculopathy or myelopathy were identified. None of these patients had previously sought for medical attention for such problems. Those patients who had severe spinal cord injury (i.e. American Spinal Injury Association scale A, B or C) or severe myelopathy (i.e. Nurick scale 4 or 5), bony fracture, dislocation, perched facet, kyphotic deformity, or instability were also excluded. An age- and sex-matched one-to-one comparison was made between patients who underwent cervical arthroplasty, on the one hand, and anterior cervical discectomy and fusion (ACDF)., Results: A total of 30 trauma patients (15 in the arthroplasty group and 15 in the ACDF group) were analyzed, with a mean follow-up of 29.6 months. The demographic data were similar. Post-operation, the arthroplasty group had significant improvement in VAS of neck and arm pain, JOA, and NDI when compared to their pre-operation status. Similarly, the ACDF group also improved significantly after the operation. There were no differences between the two groups in post-operative VAS neck and arm pain, and JOA scores. The arthroplasty group maintained a range of motion in the indexed levels and had better NDI scores at 6-months post-operation than the ACDF group., Conclusions: For selected patients (i.e. no spinal cord injury, no fracture, and no instability) with traumatic cervical disc herniation, cervical arthroplasty yields similar improvement in clinical outcomes to ACDF and preserves segmental mobility.