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The central nervous system (CNS) plays a central role in the control of sensory and motor functions, and the disruption of its barriers can result in severe and debilitating neurological disorders. Neurotrophins are promising therapeutic agents for neural regeneration in the damaged CNS. However, their penetration across the blood-brain barrier remains a formidable challenge, representing a bottleneck for brain and spinal cord therapy. Herein, a nanocapsule-based delivery system is reported that enables intravenously injected nerve growth factor (NGF) to enter the CNS in healthy mice and nonhuman primates. Under pathological conditions, the delivery of NGF enables neural regeneration, tissue remodeling, and functional recovery in mice with spinal cord injury. This technology can be utilized to deliver other neurotrophins and growth factors to the CNS, opening a new avenue for tissue engineering and the treatment of CNS disorders and neurodegenerative diseases., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Central nervous system (CNS) diseases are the leading cause of morbidity and mortality; their treatment, however, remains constrained by the blood-brain barrier (BBB) that impedes the access of most therapeutics to the brain. A CNS delivery platform for protein therapeutics, which is achieved by encapsulating the proteins within nanocapsules that contain choline and acetylcholine analogues, is reported herein. Mediated by nicotinic acetylcholine receptors and choline transporters, such nanocapsules can effectively penetrate the BBB and deliver the therapeutics to the CNS, as demonstrated in mice and non-human primates. This universal platform, in general, enables the delivery of any protein therapeutics of interest to the brain, opening a new avenue for the treatment of CNS diseases., (© 2019 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Study Design: This is a systematic review and meta-analysis., Objective: This study's goal was to (i) assess the clinical outcomes with and without vertebral augmentation (VA) for osteoporotic vertebral compression fractures (VCFs) with versus without correlating signs and symptoms; and (ii) acute (symptoms <3 mo duration) and subacute VCFs (3-6 mo duration) versus chronic VCFs (>6 mo)., Summary of Background Data: Previously, a randomized controlled trial in the New England Journal of Medicine concluded that vertebroplasty for osteoporotic VCFs provided no clinical benefit over sham surgery. However, the VCFs examined had no clinical correlation with symptom, physical examination, or imaging (magnetic resonance imaging/bone scan) findings. Nonetheless, the randomized controlled trial resulted in a reduction in VA performed in the United States. Currently, no consensus exists on VA versus nonoperative care for symptomatic VCFs (SVFs)., Materials and Methods: A literature search was conducted for studies on VA and conservative management for VCFs. Meta-analysis was performed using the random-effects model. The primary outcome was improvement in lower back pain visual analog score. SVFs were defined as radiographic VCF with clinical correlation. Radiographic-alone VCF (RVF) was defined as radiographic VCF without clinical correlation., Results: Thirteen studies totaling 1467 patients with minimum 6-month follow-up were found. Pain reduction was greater with VA over conservative management for SVFs (P<0.000001) and equivalent for RVFs (P=0.22). Subanalysis for acute/subacute SVFs and chronic SVFs showed that VA was superior to nonoperative care (P=0.0009 and 0.04, respectively). No difference was observed in outcomes between VA and nonoperative care for chronic RVF (P=0.22)., Conclusions: VA is superior to nonoperative care in reducing lower back pain for osteoporotic VCFs with correlating signs and symptoms. VA had no benefit over nonoperative care for chronic VCFs that lacked clinical correlation. Lower back pain has many etiologies and patients should be clinically assessed before recommending VA.

Background: Scoliosis X-rays are the gold standard for assessing preoperative lumbar lordosis; however, particularly for flexible lumbar deformities, it is difficult to predict from these images the extent of correction required, as standing radiographs cannot predict the thoracolumbar alignment after intraoperative positioning., Objective: To determine the utility of preoperative MRI in surgical planning for patients with flexible sagittal imbalance., Methods: We identified 138 patients with sagittal imbalance. Radiographic parameters including pelvic incidence and lumbar lordosis were obtained from images preoperatively., Results: The mean difference was 2.9° between the lumbar lordosis measured on supine MRI as compared to the intraoperative X-rays, as opposed to 5.53° between standing X-rays and intraoperative X-ray. In patients with flexible deformities (n = 24), the lumbar lordosis on MRI measured a discrepancy of 3.08°, as compared to a discrepancy of 11.46° when measured with standing X-ray., Conclusion: MRI adequately determined which sagittal deformities were flexible. Furthermore, with flexible sagittal deformities, lumbar lordosis measured on MRI more accurately predicted the intraoperative lumbar lordosis than that measured on standing X-ray. The ability to preoperatively predict intraoperative lumbar lordosis with positioning helps with surgical planning and patient counseling regarding expectations and risks of surgery.

Consensus is lacking regarding optimal surgical treatment of recurrent lumbar disk herniation. A systematic search of multiple databases was conducted for studies evaluating outcomes after treatment for recurrent lumbar disk herniation. Treatment options included decompression surgeries and fusion surgeries. Although fusion surgeries eliminated re-recurrence of disk herniation, this coincided with higher incidences of complications and reoperation. Decompression surgeries and fusion surgeries both resulted in improvements in Japanese Orthopaedic Association, Oswestry Disability Index, and visual analog scale back and leg scores postoperatively (P<.05). The complication risk profiles of decompression surgeries and fusion surgeries must be balanced with the risk of disk herniation re-recurrence, as both procedures lead to improvements in functional outcomes. [Orthopedics. 2018; 41(4):e457-e469.]., (Copyright 2018, SLACK Incorporated.)

Study Design: Systematic review and meta-analysis., Objective: Compare the radiographic and clinical outcomes of anterior lumbar interbody fusion (ALIF) to transforaminal lumbar interbody fusion (TLIF)., Summary of Background Data: ALIF and TLIF are 2 methods of achieving spinal arthrodesis. There are conflicting reports with no consensus on the optimal interbody technique to achieve successful radiographic and clinical outcomes. The goal of this systematic review and meta-analysis was to compare the radiographic and clinical outcomes of ALIF to TLIF., Materials and Methods: A systematic search of multiple medical reference databases was conducted for studies comparing ALIF to TLIF. Studies that included stand-alone ALIFs were excluded. Meta-analysis was performed using the random-effects model for heterogeneity. Radiographic outcome measures included segmental and overall lumbar lordosis, and fusion rates. Clinical outcomes measures included Oswestry disability index (ODI) and visual analog scale (VAS) score for back pain., Results: The search yielded 7 studies totaling 811 patients (ALIF=448, TLIF=363). ALIF was superior to TLIF in restoring segmental lumbar lordosis at L4-L5 and L5-S1 (L4-L5; P=0.013, L5-S1; P<0.001). ALIF was also superior to TLIF in restoring overall lumbar lordosis (P<0.001). However, no significant differences in fusion rates were noted between both techniques [odds ratio=0.905; 95% confidence interval, 0.458-1.789; P=0.775]. In addition, ALIF and TLIF were comparable with regards to ODI and VAS scores (ODI; P=0.184, VAS; P=0.983)., Conclusions: For the restoration of lumbar lordosis, ALIF is superior to TLIF. However, TLIF is comparable to ALIF with regards to fusion rate and clinical outcomes.

Introduction: Vertebral compression fracture incidence is rising with the growth of the geriatric population and is one of the leading disabilities in healthcare. However, the literature is conflicted on the benefits of vertebral augmentation versus nonoperative care for these fractures. The purpose of the current study was to perform a review of all meta-analyses in the literature comparing vertebral augmentation to nonoperative care and descriptively report the results., Methods: A review of all meta-analyses evaluating trials of vertebral augmentation compared with nonoperative care was performed. The primary outcome studied was pain. Secondary outcomes were quality of life (QoL) metrics and functional outcomes., Results: Ten studies met the inclusion criteria. Besides two sham procedure studies, the remaining literature concluded that vertebral augmentation was superior to nonoperative care for reducing back pain. The reporting of secondary outcomes, such as QoL metrics and functional outcomes, was heterogeneous among the studies. Studies that reported these secondary outcomes, however, did identify some early benefit in vertebral augmentation., Conclusions: The current literature suggests vertebral augmentation is more effective in improving pain outcomes compared with nonoperative management. While more studies are needed to conclusively assess vertebral augmentation's efficacy in improving functional outcome and QoL, the meta-analyses surveyed here suggest that at least some benefit exists when assessing these two outcomes., Competing Interests: Conflicts of Interest: The authors declare no conflicts of interest, except Steven Garfin, MD: AO North America: Research support; Benvenue Medical: Paid consultant; DePuy, A Johnson & Johnson Company: IP royalties; Paid consultant; Research support; EBI: Paid consultant; Research support; Elsevier: Publishing royalties, financial or material support; Globus Medical: Paid consultant; Research support; Harcourt: Publishing royalties, financial or material support; International Society for the Advancement of Spine Surgeons: Board or committee member; Intrinsic Therapeutics: Paid consultant; Journal of Bone and Joint Surgery - American: Editorial or governing board; Lippincott: Publishing royalties, financial or material support; Magnifi Group: Paid consultant; Medtronic: Research support; Mosby: Publishing royalties, financial or material support; Nuvasive: Paid consultant; Research support; SI Bone: Paid consultant; Stock or stock options; SLACK Incorporated: Editorial or governing board; Spinal Kinetics: Paid consultant; Spine: Editorial or governing board; Synthes: Research support; Thieme Publishers: Publishing royalties, financial or material support; Vertiflex: Paid consultant; Wolters Kluwer Health - Lippincott Williams & Wilkins: Editorial or governing board; Publishing royalties, financial or material support

Study Design: Retrospective case series with prospective arm., Purpose: To assess the safety and accuracy of percutaneous lumbosacral pedicle screw placement (PLPSP) in the lumbosacral spine using intraoperative dual-planar fluoroscopy (DPF)., Overview of Literature: There are several techniques available for achieving consistent, safe, and accurate results with PLPSP. There is a paucity of literature describing the beneficial operative, economic, and clinical outcomes of DPF, the most readily accessible image guidance system., Methods: From 2004 to 2014, 451 consecutive patients underwent PLPSP using DPF, for a total of 2,345 screw placement. The results of prospectively obtained postoperative computed tomography (CT) examinations of an additional 41 consecutive patients were compared with the results of 104 CT examinations obtained postoperatively due to clinical symptomatology; these results were interpreted by three reviewers. The rates of revision indicated by misplaced screws with consistent clinical symptomatology were compared between groups. Pedicle screw placement was graded according to 2-mm increments in medial pedicle wall breach and measurement of screw axis placement., Results: Seven of the 2,345 pedicle screws placed percutaneously with the use of the dual-planar fluoroscopic technique required revision because of a symptomatic misplaced screw, for a screw revision rate of 0.3%. There were no statistically significant demographic differences between patients who had screws revised and those who did not. All screws registered greater than 10 mA on electromyographic stimulation. In the 41 prospectively obtained CT examinations, one out of 141 screws (0.7%) was revised due to pedicle wall breach; whereas among the 104 patients with 352 screws, three screws were revised (0.9%)., Conclusions: DPF is an extremely accurate, safe, and reproducible technique for placement of percutaneous pedicle screws and is a readily available and cost-effective alternative to CT-guided pedicle screw placement techniques. Postoperative CT evaluation is not necessary with PLPSP unless the patient is symptomatic. Acceptable electromyographic thresholds may need to be reevaluated., Competing Interests: Conflict of Interest: No potential conflict of interest relevant to this article was reported.

Although several options are available to address adjacent segment disease (ASD), the most effective surgical treatment has not been determined. In addition, it is important to subdivide ASD into stenosis with or without instability to determine if a decompression alone vs an extension of fusion is necessary. A systematic search of multiple medical reference databases was conducted for studies on surgical treatment of ASD. The primary outcome measures used were radiographic and clinical success rates. Meta-analysis was completed to determine effect summary values, 95% confidence intervals, and Q statistic and I 2 values, using the random effects model for heterogeneity. The search yielded 662 studies, of which 657 were excluded. A total of 5 (level IV) studies with a total of 118 patients were included in this review. In 2 studies (46 patients), stenosis without instability was the indication for reoperation for ASD. However, extension of fusion was the modality of choice for the treatment of ASD in all studies. Overall clinical improvement (in back and/or leg pain scores) was noted in 71.3% of patients (95% confidence interval, 37.4-100), while radiographic fusion was noted in 89.3% of patients (95% confidence interval, 51.2-100). Following reoperation for ASD, revision surgery rates ranged from 4.5% to 23.1% at last clinical follow-up. There is variability in the clinical improvement following lumbar fusion for ASD. In addition, little literature exists regarding the optimal treatment options for patients with ASD for stenosis with or without instability. [Orthopedics. 2018; 41(2):e161-e167.]., (Copyright 2017, SLACK Incorporated.)

Study Design: This is a epidemiological database analysis., Objectives: The objectives of this article are to assess the following characteristics of vertebral osteomyelitis (VO): (1) incidence and patient demographics, (2) mortality rate, (3) length-of-stay (LOS), and (4) admission costs., Summary of Background: VO is a serious disease with potentially devastating clinical consequences. At present, there is limited data on the epidemiology of VO in the United States as previous reports are based on older studies with small sample sizes., Methods: We used the Nationwide Inpatient Sample database and estimated that 228,044 patients were admitted for VO in the United States between 1998 and 2013. Data were extracted on patient demographics, comorbidities, inpatient mortality, LOS, and inflation-adjusted hospitalization charges. Multivariable regression analyses were performed., Results: The incidence of VO admission was 4.8 per 100,000, increasing from 8021 cases (2.9/ 100,000) in 1998 to 16,917 cases (5.4/100,000) in 2013. Majority of patients were white (74%), male (51%), younger than 59 years of age (49.5%), and carried Medicare insurance (50%). The increase in incidence for male and females was similar. The mortality rate during hospital stay was 2.1%, decreasing from 2% in 1998 to 1.7% in 2006 and increasing to 2.2% in 2013. Risk factors for mortality included increased age, male sex, and higher comorbidity score. History of congestive heart failure [odds ratio (OR)=2.45], cerebrovascular disease (OR=1.92), liver disease (OR=2.33), hepatitis C (OR=2.36), and renal disease (OR=1.88) was associated with higher mortality rate. Mean LOS was 9.2 days, decreasing from 9.1 days in 1998 to 8.8 days in 2013. The mean estimated hospital charges for admission were $54,599, however, this increased from $24,102 in 1998 (total of $188.8 millions) to $80,786 in 2013 (total of $1.3 billions)., Conclusion: This condition is associated with lengthy and expensive hospital stays resulting in a significant burden to patients and the health care system.

Study Design: Systematic review and meta-analysis., Objective: The purpose of this study was to evaluate the effect of postoperative ketorolac administration (ie, dosage and duration of use) on pseudarthrosis following thoracolumbar posterolateral spinal fusions., Summary of Background Data: Ketorolac is a nonsteroidal anti-inflammatory drug often administered for pain control after spine surgery. The main concern with ketorolac is the risk of pseudarthrosis following fusion., Materials and Methods: A systematic search of multiple medical reference databases was conducted for studies detailing postoperative ketorolac use in lumbar fusion and scoliosis surgery in adult and pediatric patients, respectively. Meta-analysis was performed using the random-effects model for heterogeneity as this study analyzes heterogenous patient populations undergoing variable approaches to fusion and variable numbers of levels with variable means of detection of pseudarthrosis. Outcome measure was pseudarthrosis., Results: Overall, 6 studies totaling 1558 patients were reviewed. Pseudarthrosis was observed in 119 (7.6%) patients. Pseudarthrosis were observed in adults with ketorolac administered for >2 days [odds ratio (OR), 3.44, 95% confidence interval (95% CI), 1.87-6.36; P<0.001], adults with doses of ≥120 mg/d (OR, 2.93, 95% CI, 1.06-8.12; P=0.039), and adults with ketorolac administered for >2 days and at doses ≥120 mg/d (OR, 4.75, 95% CI, 2.34-9.62; P<0.001). Ketorolac use in smokers was associated with pseudarthrosis (OR, 8.71, 95% CI, 2.23-34.0; P=0.002)., Conclusion: Ketorolac, when administered for >2 days and/or at a dose of ≥120 mg/d, is associated with pseudarthrosis in adults after posterolateral lumbar fusion. Ketorolac use in smokers is also associated with pseudarthrosis.

OBJECTIVE The flexed posture of the proximal (L1-3) or distal (L4-S1) lumbar spine increases the diameter of the spinal canal and neuroforamina and can relieve symptoms of neurogenic claudication. Distal lumbar flexion can result in pelvic retroversion; therefore, in cases of flexible sagittal imbalance, pelvic retroversion may be compensatory for lumbar stenosis and not solely compensatory for the sagittal imbalance as previously thought. The authors investigate underlying causes for pelvic retroversion in patients with flexible sagittal imbalance. METHODS One hundred thirty-eight patients with sagittal imbalance who underwent a total of 148 fusion procedures of the thoracolumbar spine were identified from a prospective clinical database. Radiographic parameters were obtained from images preoperatively, intraoperatively, and at 6-month and 2-year follow-up. A cohort of 24 patients with flexible sagittal imbalance was identified and individually matched with a control cohort of 23 patients with fixed deformities. Flexible deformities were defined as a 10° change in lumbar lordosis between weight-bearing and non-weight-bearing images. Pelvic retroversion was quantified as the ratio of pelvic tilt (PT) to pelvic incidence (PI). RESULTS The average difference between lumbar lordosis on supine MR images and standing radiographs was 15° in the flexible cohort. Sixty-eight percent of the patients in the flexible cohort were diagnosed preoperatively with lumbar stenosis compared with only 22% in the fixed sagittal imbalance cohort (p = 0.0032). There was no difference between the flexible and fixed cohorts with regard to C-2 sagittal vertical axis (SVA) (p = 0.95) or C-7 SVA (p = 0.43). When assessing for postural compensation by pelvic retroversion in the stenotic patients and nonstenotic patients, the PT/PI ratio was found to be significantly greater in the patients with stenosis (p = 0.019). CONCLUSIONS For flexible sagittal imbalance, preoperative attention should be given to the root cause of the sagittal misalignment, which could be compensation for lumbar stenosis. Pelvic retroversion can be compensatory for both the lumbar stenosis as well as for sagittal imbalance.

Study Design: A retrospective database study., Objective: The goal of this study was to (1) evaluate the trends in the use of electromyography (EMG) for instrumented posterolateral lumbar fusions (PLFs) in the United States and (2) assess the risk of neurological injury following PLFs with and without EMG., Summary of Background Data: Neurologic injuries from iatrogenic pedicle wall breaches during screw placement are known complications of PLFs. The routine use of intraoperative neuromonitoring (ION) such as EMG during PLF to improve the accuracy and safety of pedicle screw implantation remains controversial., Methods: A retrospective review was performed using the PearlDiver Database to identify patients who had PLF surgery with and without EMG for lumbar disorders from years 2007 to 2015. Patients undergoing concomitant interbody fusions or spinal deformity surgery were excluded. Demographic trends and risk of neurological injuries were assessed., Results: During the study period, 2007 to 2015, 9957 patients underwent PLFs. Overall, EMG was used in 2495 (25.1%) of these patients. There was a steady increase in the use of EMG from 14.9% in 2007 to 28.7% in 2009, followed by a steady decrease to 21.9% in 2015 (P < 0.0001). The risk of postoperative neurological injuries following PLFs was 1.35% (134/9957) with a risk of 1.36% (34/2495) with EMG and 1.34% (100/7462) without EMG (P = 0.932). EMG is used most commonly for PLFs in the Southern part of the United States., Conclusion: In this retrospective national database review, we found that there was a steady increase in the routine use of EMG for PLFs followed by a steady decline. Regional differences were observed in the utility of EMG for PLFs. The risk of neurological complications following PLF in the absence of spinal deformity is low and the routine use of EMG for PLF may not decrease the risk., Level of Evidence: 4.

Study Design: Systematic review and meta-analysis., Objective: The goal of this study was to (i) assess the risk of neurological injury after anterior cervical spine surgery (ACSS) with and without intraoperative neuromonitoring (ION) and (ii) evaluate differences in the sensitivity and specificity of ION for ACSS., Summary of Background Data: Although ION is used to detect impending neurological injuries in deformity surgery, it's utility in ACSS remains controversial., Methods: A systematic search of multiple medical reference databases was conducted for studies on ION use for ACSS. Studies that included posterior cervical surgery were excluded. Meta-analysis was performed using the random-effects model for heterogeneity. Outcome measure was postoperative neurological injury., Results: The search yielded 10 studies totaling 26,357 patients. The weighted risk of neurological injury after ACSS was 0.64% (0.23-1.25). The weighted risk of neurological injury was 0.20% (0.05-0.47) for ACDFs compared with 1.02% (0.10-2.88) for corpectomies. For ACDFs, there was no difference in the risk of neurological injury with or without ION (odds ratio, 0.726; confidence interval, CI, 0.287-1.833; P = 0.498). The pooled sensitivities and specificities of ION for ACSS are 71% (CI: 48%-87%) and 98% (CI: 92%-100%), respectively. Unimodal ION has a higher specificity than multimodal ION [unimodal: 99% (CI: 97%-100%), multimodal: 92% (CI: 81%-96%), P = 0.0218]. There was no statistically significant difference in sensitivities between unimodal and multimodal [68% vs. 88%, respectively, P = 0.949]., Conclusion: The risk of neurological injury after ACSS is low although procedures involving a corpectomy may carry a higher risk. For ACDFs, there is no difference in the risk of neurological injury with or without ION use. Unimodal ION has a higher specificity than multimodal ION and may minimize "subclinical" intraoperative alerts in ACSS., Level of Evidence: 3.

Little literature exists examining differences in presentation and outcomes between monomicrobial and polymicrobial vertebral infections. Seventy-nine patients treated for vertebral osteomyelitis between 2001 and 2011 were reviewed. Patients were divided into monomicrobial and polymicrobial cohorts based on type of infection. Various characteristics were compared between the 2 groups. The 26 patients with a polymicrobial infection were older and had a higher mortality rate, lower clearance of infection, larger infection, more vertebral instability, higher erythrocyte sedimentation rate at presentation, and longer mean length of stay. There were no significant differences in Oswestry Disability Index scores at final follow-up, but there were differences in presentation and clinical outcomes between monomicrobial and polymicrobial vertebral osteomyelitis. Patients may benefit from counseling regarding their disease type and potential prognosis. [Orthopedics. 2017; 40(2):e370-e373.]., (Copyright 2016, SLACK Incorporated.)

Study Design: A retrospective database study., Objective: The goal of this study was to (1) evaluate the trends in the use of intraoperative neuromonitoring (ION) for anterior cervical discectomy and fusion (ACDF) surgery in the United States and (2) assess the incidence of neurological injuries after ACDFs with and without ION., Summary of Background Data: Somatosensory-evoked potentials (SSEPs) and motor-evoked potentials (MEPs) are the commonly used ION modalities for ACDFs. Controversy exists on the routine use of ION for ACDFs and there is limited literature on national practice patterns of its use., Methods: A retrospective review was performed using the PearlDiver Patient Record Database to identify cases of spondylotic myelopathy and radiculopathy that underwent ACDF from 2007 to 2014. The type of ION modality used and the rates of neurological injury after surgery were assessed., Results: During the study period, 15,395 patients underwent an ACDF. Overall, ION was used in 2627 (17.1%) of these cases. There was a decrease in the use of ION for ACDFs from 22.8% in 2007 to 4.3% use in 2014 (P < 0.0001). The ION modalities used for these ACDFs were quite variable: SSEPs only (48.7%), MMEPs only (5.3%), and combined SSEPs and MMEPs (46.1%). Neurological injuries occurred in 0.23% and 0.27% of patients with and without ION, respectively (P = 0.84). Younger age was associated with a higher utility of ION (<45: 20.3%, 45-54: 19.3%, 55-64: 16.6%, 65-74: 14.3%, and >75: 13.6%, P < 0.0001). Significant regional variability was observed in the utility of ION for ACDFs across the country (West; 21.9%, Midwest; 12.9% (P < 0.0001)., Conclusion: There has been a significant decrease in the use of ION for ACDFs. Furthermore, there was significant age and regional variability in the use of ION for ACDFs. Use of ION does not further prevent the rate of postoperative neurological complications for ACDFs as compared with the cases without ION. The utility of routine ION for ACDFs is questionable., Level of Evidence: 3.

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) has been shown to have long-term clinical outcomes similar to those with open TLIF and decreased perioperative morbidity. This study assessed whether this procedure can be safely performed in outpatient settings. Ninety-six consecutive patients undergoing 1- or 2-level MIS-TLIFs were retrospectively reviewed. They were divided into inpatient and outpatient cohorts (36%). All had a minimum of 2 years of follow-up. Patient demographics, comorbidities, complications, and readmissions were examined. Early postoperative complications were stratified into wound related, infection, neurologic, implant related, and vascular injuries. Patients in the outpatient cohort were significantly younger, had lower American Society of Anesthesiologists physical status scores, and had lower Charlson Comorbidity Index scores than patients in the inpatient cohort. There were no statistically significant differences in overall postoperative complication rates, readmission rates, or final Oswestry Disability Index or visual analog scale scores between the 2 cohorts. The clinical outcomes of the outpatient TLIF procedure were similar to those of the inpatient procedure and it had an acceptable complication rate. [Orthopedics. 2016; 39(6):e1218-e1222.]., (Copyright 2016, SLACK Incorporated.)

Background: How the relative volume of an epidural abscess on MRI affects outcomes with antibiotics alone has limited literature. The purpose of this study was to identify which infected epidural collections will reabsorb with antibiotics alone. Specifically, what is the critical size and enhancement on contrast MRIs to require a drainage procedure?, Materials and Methods: A retrospective review of all spinal osteomyelitis patients from 2001-2012 was performed. Inclusion criteria included appropriate initial imaging, lab results, no drainage procedures of collections, and no treatment prior to admission at an outside institution. Large size epidural abscess was defined as abscesses with a volume greater than 1400 mm3. Clearance and mortality rates were evaluated., Results: The cohort consisted of 128 patients including 76 men and 52 women who had a mean age of 62 years (range, 21 to 90 years) and had a mean follow-up of 38 months (range, 24 to 72 months). Patients with a large epidural abscess had a greater clearance rate of the infection and decreased mortality rate when treated with surgery or drainage compared to patients treated with antibiotics alone [clearance: p=0.048; mortality: p=0.048]. Those small epidural abscesses had similar clearance and mortality rates when treated with surgery or drainage compared to antibiotics alone [clearance: p=0.75; mortality: p=0.13]. Patients with non-enhancing epidural abscesses had similar clearance rates-but increased mortality rates-when treated with antibiotics alone compared to surgery or drainage [clearance: p>0.9; mortality: p=0.03]. Those with enhancing epidural collections had similar clearance and mortality rates when treated with antibiotics alone compared to surgery or drainage [clearance: p=0.08, mortality: p=0.10]., Conclusion: Large epidural infected collections require surgery or a percutaneous drainage procedure. Clearance rates are higher and mortality rates are lower compared to non-operative management in these instances. Neurologically intact patients with a small epidural collection can be treated with antibiotics alone with good expected outcomes.

Introduction: Obtaining blood or tissue cultures prior to administration of antibiotics has been the standard of care in the treatment of osteomyelitis of the spine. A delay in diagnosis of vertebral osteomyelitis is the primary culprit for the inaccuracy of blood cultures and biopsies. The purpose of this study was to evaluate the outcomes of spinal osteomyelitis in patients where the infecting organism was identified through cultures in contrast to cases where the cultures continued to be negative., Materials and Methods: We retrospectively reviewed the database of spinal osteomyelitis cases presented at a high-volume institution from 2001-2011. This resulted in 91 patients (51 men and 40 women) who had a mean age of 59 years with a mean follow-up of four years. Delay in diagnosis was defined as greater than 2.5 months from first ER visit for non-specific back pain to diagnosis of osteomyelitis without antibiotic treatment in the interim. Nineteen patients had a delay in diagnosis (DD) and 72 were diagnosed early (ED). Outcomes evaluated include clearance of infection, clinical outcomes measured by Oswestry disability index scores (ODIs), and the efficacy of blood cultures and biopsies., Results: The ED group had a higher odds ratio of osteomyelitis clearance compared to the delay in diagnosis group and this trended toward significance [p=0.08]. The mean improvements in ODIs were significantly greater in the ED group compared to the DD group. Positive blood cultures were more positive when drawn within one month compared to after one month [p=.001]. Percutaneous biopsy cultures were more positive when drawn within 2.5 months compared to after 2.5 months [p=.025]. Open biopsy cultures were more positive when drawn within 4.5 months compared to after that [p<0.001]., Discussion: We found that delayed diagnosis may negatively affect the treatment outcome as evidenced by the greater improvements in ODI scores among those diagnosed early. Although we were unable to show a difference in clearance between early and delayed diagnosis, it is quite possible that larger cohorts may have shown this given the trend toward significance., Conclusion: Hence, an early diagnosis has improved vertebral osteomyelitis clearance and clinical outcomes, and blood cultures and biopsies may have a low yield if delayed.

The purpose of this study was to compare the outcomes of instrumented versus noninstrumented (decompression) surgical treatment of vertebral osteomyelitis. The study population included 104 patients with spinal osteomyelitis who were treated at the authors' institution between 2004 and 2012. This included 62 men and 42 women who underwent either instrumented (n=57) or noninstrumented (n=47) surgery. Mean patient age was 59 years, and mean follow-up was 38 months (range, 12-78 months). Specifically, the following criteria were assessed: mortality rates, infection clearance rates, clinical outcomes measured by Oswestry Disability Index (ODI), mean length of stay, and baseline differences between the 2 cohorts. Although patients in the instrumented cohort had more instability, more neurologic symptoms, and larger volume infection, they had similar clearance of infection (54% vs 42.5%; odds ratio [OR], 1.55; 95% confidence interval [CI], 0.61-3.9; P=.35), mortality rate (9% vs 17%; OR, 0.47; 95% CI, 0.14-1.54; P=.21), and ODI scores (40 vs 45 points; P=.32) compared with patients in the noninstrumented group. However, mean length of stay (19 vs 13 days; P=.02) was significantly higher for patients in the instrumented group. Even in more severe cases of vertebral osteomyelitis, instrumentation resulted in comparable outcomes to decompression. [Orthopedics. 2016; 39(3):e504-e508.]., (Copyright 2016, SLACK Incorporated.)

Purpose: Recent work has shown the safety and efficacy of halo-gravity traction as an operative adjunct. However, there are no reports specifically looking at halo-gravity traction in patients with skeletal dysplasia. Our purpose was to assess the safety and efficacy of traction in children with skeletal dysplasia who present with severe kyphoscoliosis., Methods: We retrospectively reviewed eight consecutive children with skeletal dysplasia who were treated with halo-gravity traction preoperatively. Six of the patients had a thoracoscopic anterior release prior to the halo-gravity traction. All patients were ambulatory and presented with severe, rigid kyphoscoliosis., Results: The mean duration of traction was 32 days. There were no neurologic complications with traction or after posterior spinal instrumentation. The majority of kyphoscoliosis correction was with the halo-gravity traction alone: major curve (MC) Cobb angle improved 41 %; C7-center sacral vertical line, 75 %; C7-MC apex, 21 %; and T2-T12 kyphosis, 35 %. Trunk height increased 37 % and thoracic height 44 %. An additional amount of correction was obtained with posterior spinal instrumentation (±fusion), decreasing MC Cobb angle an additional 23 %; C7-apex, 16 %; and T2-T12 kyphosis, 10 %. There was no additional correction of thoracic height. Two years after posterior spinal instrumentation (±fusion), a mild-to-moderate amount of correction was lost: MC Cobb angle decreased 23 %; compensatory Cobb angle, 28 %; C7-CSVL, 24 %; C7-S1, 22 %; regional kyphosis, 31 %; thoracic kyphosis, 29 %; and trunk height, 27 %., Conclusions: Among children with skeletal dysplasia and severe kyphosis, halo-gravity traction is well tolerated and safe. Most of the corrections in radiographic parameters were achieved with traction alone. Traction improves coronal balance, apical translation, thoracic height, and kyphosis. In this specific population, the potential for neurologic injury during corrective surgery is high. However, preoperative halo-gravity traction provides slow, progressive correction in a safe manner and avoided neurologic injury in these patients. This study did not compare patients without halo-gravity traction to patients with halo-gravity traction, therefore it cannot be concluded that going straight to instrumentation without traction will give a poorer radiographic result., Level of Evidence: IV.

Paraspinal muscles are commonly affected during spine surgery. The purpose of this study was to assess the potential factors that contribute to paraspinal muscle atrophy (PMA) after lumbar spine surgery. A comprehensive review of the available English literature, including relevant abstracts and references of articles selected for review, was conducted to identify studies that reported PMA after spinal surgery. The amount of postoperative PMA was evaluated in (1) lumbar fusion vs nonfusion procedures; (2) posterior lumbar fusion vs anterior lumbar fusion; and (3) minimally invasive (MIS) posterior lumbar decompression and/or fusion vs non-MIS equivalent procedures. In total, 12 studies that included 529 patients (262 men and 267 women) were reviewed. Of these, 365 patients had lumbar fusions and 164 had lumbar decompressions. There was a significantly higher mean postoperative volumetric PMA with fusion vs nonfusion procedures (P=.0001), with posterior fusion vs anterior fusion (P=.0001), and with conventional fusions vs MIS fusions (P=.001). There was no significant difference in mean volumetric lumbar PMA with MIS decompression vs non-MIS decompression (P=.56). There was significantly higher postoperative PMA with lumbar spine fusions, posterior procedures, and non-MIS fusions., (Copyright 2016, SLACK Incorporated.)

The purpose of this study was to evaluate the long-term clinical and radiographic outcomes of posterolateral lumbar fusion for lumbar stenosis cases requiring bilateral facetectomy in conjunction with a laminectomy. The authors evaluated 34 consecutive patients who had undergone a lumbar laminectomy, bilateral partial facetectomy, and posterolateral fusion at a single institution between 1981 and 1996. They included 25 men and 9 women with a mean age of 42 years (range, 27-57 years). Twenty-three cases were instrumented and 11 were noninstrumented. Mean follow-up was 21 years (range, 15-29 years). Outcomes evaluated included reoperation rate, clinical outcomes evaluated by the Oswestry Disability Index (ODI) score, radiographic evaluations of adjacent segmental degeneration (ASD) and lumbar lordosis, and contributing demographic factors to disease progression. At final follow-up, 17 of the 34 patients had undergone reoperation (43% of the instrumented group and 64% of the noninstrumented group). There were no differences in the reoperation rate or ODI improvement between the instrumented and noninstrumented groups (P>.05). Female patients required more revisions, had less ODI improvement, had greater postoperative ASD, and had less maintenance of their postoperative lumbar lordosis. There was no difference in maintenance of postoperative lumbar lordosis or ASD between the instrumented and noninstrumented groups. Instrumentation did not improve revision rates, clinical outcomes, or radiographic outcomes in laminectomies requiring contemporaneous facetectomies., (Copyright 2015, SLACK Incorporated.)

Study Design: Retrospective clinical and radiographic review., Objective: The purpose of this study was to evaluate the characteristics of deep wound infection, as well as the potential factors that correlate to surgical site infection (SSI) in spine deformity surgery., Summary of Background Data: Preventing SSIs in pediatric spinal deformity surgery is a crucial task. Recent data have shown that antibiotic-loaded allograft and properly timed preoperative antibiotic administration decrease SSIs. However, there remain controversies over the appropriate preoperative antibiotic selection., Methods: We reviewed 851 spinal deformity surgeries that took place at a single institution from 2006 to 2010. In particular, preoperative and postoperative characteristics of the deep wound infections were evaluated., Results: Twenty-four patients had SSIs. The mean age at surgery in the infected cohort was 14 years, mean length of surgery was 8 hours, and median estimated blood loss was 2,482 mL (%EBV: 66%). Approximately 67% of the infected patients had bowel/bladder incontinence, and 71% had prolonged intravenous access perioperatively. According to culture results, the most effective antibiotic to treat the infections was vancomycin. Preoperative antibiotics were administered within 30 minutes of incision (hospital protocol) in only 12.5% (p = .001) and within 1 hour of incision in 54% of the cases. The wound status within 3 days of surgery is as follows: 38% intact, 29% significant wound drainage, and 33% wound dehiscence. Methicillin-resistant Staphylococcus aureus (MRSA) and oxacillin-resistant Staphylococcus epidermidis were associated with intact wounds, whereas gram-negative pathogens were seen in dehisced or draining wounds (p < .001)., Conclusions: The authors showed that their cohort of patients with infection had a high rate of draining wounds, MRSA infections, administration of antibiotics more than 1 hour ahead of incision, and prolonged need for intravenous access after surgery. Efforts to mitigate these associations by using vancomycin prophylactically, doing meticulous wound closure to prevent drainage or dehiscence, and delivering antibiotics at an optimal time ahead of incision may lead to a decrease in infection rates in pediatric spinal surgery. Future prospective studies will be needed to validate this., (Copyright © 2015 Scoliosis Research Society. Published by Elsevier Inc. All rights reserved.)

This study evaluated the safety of 3-level anterior cervical diskectomy and fusion (ACDF) with ultra-low-dose recombinant bone morphogenetic protein-2 (rhBMP-2). Thirty-seven consecutive patients with cervical spondylotic myelopathy who were treated with 3-level ACDF and rhBMP-2 were evaluated. Complications such as airway or cervical swelling or hematoma were not observed. The rate of dysphagia was no different at 1, 2, and 6 months postoperatively compared with reports in the literature without rhBMP-2. There were significant improvements in VAS neck/arm pain, Oswestry Neck Disability Index, and cervical lordosis. The use of ultra-low-dose rhBMP-2 for 3-level ACDF may be efficacious for surgically addressing 3-level spondylotic myelopathy., (Copyright 2015, SLACK Incorporated.)

Bisphosphonates are the most commonly prescribed drugs to treat osteoporosis because they have been proposed to prevent bone loss. Nevertheless, in up to 0.1% of patients, long-term use may cause atypical stress or insufficiency femoral fractures. Bilateral femoral shaft fractures have been reported after long-term use of bisphosphonates; however, there is limited evidence of the effect of short-term use. The current study reports a case of bilateral femoral fractures after a low-energy fall in a 56-year-old woman and provides a review of the literature on bilateral femoral shaft fractures after long-term use of bisphosphonates. Patients should be educated about the potential for stress fractures with the use of this treatment. In patients with thigh pain, a thorough history and physical examination, including the contralateral thigh, may be beneficial to detect bilateral traumatic or atypical stress fracture patterns. More studies with larger sample sizes are necessary to better identify patients who may be at risk for fracture, including histomorphometric evidence of low bone turnover in patients with unfortunate bilateral cases., (Copyright 2015, SLACK Incorporated.)

Background: One of the most important goals of primary total knee arthroplasty (TKA) is to achieve a functional range of motion (ROM). However, up to 20% of patients fail to do so, which can impair activities of daily living., Questions/purposes: The purpose of this study was to evaluate the effect of various (1) demographic factors; (2) comorbidities; and (3) knee-specific factors on the frequency of manipulation under anesthesia, which was used as an indicator of knee stiffness after a primary TKA., Methods: We evaluated the registries of two high-volume centers and reviewed all 3182 TKAs that were performed between 2005 and 2011 to identify all patients who had undergone manipulation under anesthesia (MUA). A total of 156 knees in 133 patients underwent MUA after an index arthroplasty. These patients were compared in a one-to-four ratio with a group of patients with satisfactory ROM drawn from the same database who met prespecified criteria and who had not undergone MUA. Effects of various factors, including age, sex, body mass index, race, comorbidities, and the underlying cause of knee arthritis, were compared between these two cohorts using multivariable logistic regressions., Results: After controlling for various confounding, nonwhite race was associated with an increase (odds ratio [OR], 2.01; p=0.03), and age≥65 years (OR, 0.17; 95% confidence interval [CI], 0.04-0.74; p=0.0179) was associated with a reduction in the incidence of MUA. In comorbidities, diabetes (OR, 1.72; 95% CI, 1.02-2.32; p=0.03), high cholesterol levels (OR, 2.70; p=0.03), and tobacco smoking (OR, 1.59; 95% CI, 1.03-2.47; p=0.03) were associated with an increase in frequency of MUA. In knee-specific factors, preoperative knee ROM of less than 100° (OR, 0.80; p<0.0001) and knee osteonecrosis (p=3.61; 95% CI, 1.29-10.1; p=0.014) were associated with increased frequency of MUA., Conclusions: We identified several demographic, medical, and knee-specific factors that were associated with poor postoperative ROM in our patients undergoing TKA. Patients who have multiple risk factors may benefit from preoperative counseling to set realistic ROM expectations., Level of Evidence: Level III, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

Background Context: The role of magnetic resonance imaging (MRI) in neurologically intact cervical spine fractures is not well defined. To our knowledge, there are no studies that clearly identify the indications for MRI in this particular scenario. Controversy remains regarding the use of MRI in at-risk patients, primarily the obtunded and elderly patients., Purpose: The purpose of the present study was to examine the predisposing conditions where an MRI would provide additional findings that would affect management in acute cervical spine fractures., Study Design: Retrospective cohort involving radiographic and clinical review., Patient Sample: Consecutive patients with acute cervical injuries at a single institution., Outcome Measures: Neurologic recovery., Methods: A review of 830 patients with cervical spinal injuries between 2006 and 2010 was performed. Clinical information was obtained for all the patients: Glasgow Coma Scale, mechanism of injury, major medical comorbidities, associated injuries, neurologic examination, neurologic symptoms, sex, age, and alertness. Two experienced fellowship-trained spine surgeons determined if the MRI study changed the management in the individual cases based on the Sub-axial Cervical Spine Injury classification system., Results: Ninety-nine patients with a cervical fracture were included in the final analysis: median age 54 years (interquartile range, 42 years), mean Glasgow Coma Scale 13 (standard deviation ± 3.0), 68% males, 32% females, 42% older patients (age>60 years), 30% spondylosis, 27% polytrauma, 67% alert, 28% neurologic deficit. Major medical comorbidities, prior to injury level of activity, atlantoaxial versus subaxial, and gender were not associated with changes in diagnosis and management (p>.05). Age >60 years, neurologic deficit, polytrauma status, alertness, and spondylosis were associated with having additional clinically relevant findings seen on MRI and changes in management (p<.05). The majority of the changes in management were related to MRI's illustration of the spinal cord injury and not due to an occult instability. Eighty-one percent of the changes in management were related to the depiction of the spinal cord compression seen on MRI, whereas 19% of the changes in management were related to occult instability seen on MRI., Conclusions: Older age (>60 years), obtunded or temporary non-assessable status, cervical spondylosis, polytrauma, and neurologic deficit are predisposing factors for further injury found on MRI but missed on computed tomographic scan alone. These additional findings can affect the management in acute cervical spine fractures. The rational of the on-call spine surgeon to order an MRI for a cervical spine fracture is well founded and often that MRI will affect the fracture management. Magnetic resonance imaging particularly helps with better defining the type of spinal cord compression. Picking up occult instability missed on computed tomographic scan was possible with MRI but not as common., (Copyright © 2014 Elsevier Inc. All rights reserved.)

Background: The current methods of assessing motor function rely primarily on the clinician's judgment of the patient's physical examination and the patient's self-administered surveys. Recently, computerized handgrip tools have been designed as an objective method to quantify upper-extremity motor function. This pilot study explores the use of the MediSens handgrip as a potential clinical tool for objectively assessing the motor function of the hand., Methods: Eleven patients with cervical spondylotic myelopathy (CSM) were followed for three months. Eighteen age-matched healthy participants were followed for two months. The neuromotor function and the patient-perceived motor function of these patients were assessed with the MediSens device and the Oswestry Disability Index respectively. The MediSens device utilized a target tracking test to investigate the neuromotor capacity of the participants. The mean absolute error (MAE) between the target curve and the curve tracing achieved by the participants was used as the assessment metric. The patients' adjusted MediSens MAE scores were then compared to the controls. The CSM patients were further classified as either "functional" or "nonfunctional" in order to validate the system's responsiveness. Finally, the correlation between the MediSens MAE score and the ODI score was investigated., Results: The control participants had lower MediSens MAE scores of 8.09%±1.60%, while the cervical spinal disorder patients had greater MediSens MAE scores of 11.24%±6.29%. Following surgery, the functional CSM patients had an average MediSens MAE score of 7.13%±1.60%, while the nonfunctional CSM patients had an average score of 12.41%±6.32%. The MediSens MAE and the ODI scores showed a statistically significant correlation (r=-0.341, p<1.14×10⁻⁵). A Bland-Altman plot was then used to validate the agreement between the two scores. Furthermore, the percentage improvement of the the two scores after receiving the surgical intervention showed a significant correlation (r=-0.723, p<0.04)., Conclusions: The MediSens handgrip device is capable of identifying patients with impaired motor function of the hand. The MediSens handgrip scores correlate with the ODI scores and may serve as an objective alternative for assessing motor function of the hand.

Osteochondroma (or osteocartilaginous exostosis) is the most common bone tumor of childhood, with an incidence ranging from 1 to 1.4 per 1,000,000. In the lumbar spine, osteochondromata usually arise from the posterior column at the secondary ossification center and grow away from the spinal canal without causing neurologic deficits. This article reports a rare intraspinal lumbar osteochondroma that compressed the thecal sac, resulting in a hip flexion contracture in an 11-year-old boy. This lumbar, intraspinal, extradural exostosis was confluent with the L3 inferior articular process and compressed the L3 nerve root and thecal sac severely. The patient underwent an en bloc resection of the tumor with a right-sided hemilaminectomy of L3 and L4, a right-sided partial facetectomy at L3 to L4, and an extended resection from the pars intra-articularis of the L2 to the L5 vertebrae. The tumor specimen measured 4.8×3.7×2.5 cm with clear margins. Instrumented posterolateral fusion was completed from L2 to L5 due to iatrogenic instability from the resection. The patient had an uneventful recovery and returned to his normal activities of daily living, including sports. He remains asymptomatic at 54-month follow-up. A solitary lumbar osteochondroma that compresses the spinal cord, resulting in a motor neurological deficit, has not been reported in a pediatric patient. Orthopedic surgeons should be aware of potential intraspinal presentation of osteochondromas. Magnetic resonance imaging is the modality of choice in diagnosing and screening for spinal osteochondromas. These cases can be treated with resection surgery., (Copyright 2014, SLACK Incorporated.)

Twenty-four consecutive patients with cervical spondylosis who were treated with cervical corpectomy and recombinant human bone morphogenetic protein-2 (rhBMP-2) with standalone anterior instrumentation were evaluated. Mean number of levels fused was 2.4. There were significant improvements in visual analog scale neck pain and Oswestry Disability Index scores and cervical lordosis. Cervical corpectomy with a lower dose of rhBMP-2 was found to be safe and efficacious for patients who are at a higher risk for pseudarthrosis.

The purpose of this study was to assess the clinical and radiographic outcomes of primary total knee arthroplasty (TKA) in morbidly obese patients compared to a cohort who had a normal body mass index (BMI). We reviewed 105 knees in 84 patients who had a minimum BMI of 40 kg/m2 who underwent a primary TKA between 2006 and 2010. There were 17 men and 67 women who had a mean age of 59 years and a mean follow-up of 52 months. Outcomes evaluated included implant survivorship, Knee Society scores, activity scores, and complications. Kaplan-Meier analysis demonstrated statistically similar overall implant survivorship between the morbidly obese and the comparison groups (96 vs 97%). However, the mean Knee Society objective (85 vs 91 points) and functional scores (84 vs 89 points), as well as activity scores (4.2 vs 6.1 points) were lower and complications were higher in morbidly obese patients at final follow-up. It is encouraging that in the morbidly obese patients, total knee arthroplasty can have acceptable results at midterm follow-up, however, these patients may benefit from preoperative counseling to have realistic expectations from their surgery.