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To investigate the epidemiology of congenital scoliosis (CS) and treatment trends. An age-matched, nationwide, population-based study was conducted using the National Health Insurance and Health Insurance Review and Assessment databases from 2010 to 2015. Data regarding the diagnosis and treatment of scoliosis were extracted using International Classifications of Diseases, 10th revision codes. The age-matched normal population was determined from the Korean Statistical Information Service database. We analyzed the incidence rate of CS according to age and sex, as well as the proportion of surgically treated patients. A total of 1664 patients (aged 0–19 years) were diagnosed with CS. The overall average incidence rate of CS over the 5-year period was 3.08 per 100,000 persons, with the highest and second highest rates at 0 years and 12–16 years of age, respectively. The incidence rate stratified by age ranged from 1.5 to 20.1 per 100,000 persons among the age-matched normal population, with peaks at 0 years of age and the second growth spurt in adolescence (12–16 years for males; 10–14 years for females). Anterior surgery was rarely performed; posterior surgery was performed in 92 patients (5.5% of all patients), with the highest prevalence (56.5%) in patients diagnosed at 10–14 years of age. The overall average incidence rate of CS over a 5-year period was 3.08 per 100,000 persons. Only 5.5% of patients underwent surgery within 5 years after the initial diagnosis.

Study Design: Prospective observational study. Objective: In ACDF, graft failure and subsidence are common complications of surgery. Depending on the cervical fixation, different biomechanical characteristics are applied on the grafts. This aims to describe the incidence of cervical spacer failure in patients with cervical degenerative condition according to the cervical fixation method and sagittal balance. Method: From November 2011 to December 2015, 262 patients who underwent cervical spine surgery were enrolled prospectively. Patients were divided into 3 groups based on fixation method: anterior plate/screw (APS), posterior lateral mass screw (LMS), pedicle screw (PPS) groups. Serial X-rays and CT scans were utilized to evaluate radiologic outcomes. Results: Mean patient ages were 56.1 years in the APS group, 61.5 years in the LMS group, and 57.6 years in the PPS group ( P = 0.002). Allospacer failure was most common in the APS group, compared to the LMS and PPS groups (chi-square, P = 0.038). Longer fusion level was associated with greater allospacer failure (Baseline 2 level surgery; Odds ratio (OR) 3.4 in 3 level, 15.2 in 4 level, P = 0.036,0.013). Higher T1 slope was correlated with less allospacer failure (OR 0.875, P = 0.001). ORs of allospacer failure in the LMS and PPS groups were 0.04 and 0.02, respectively, ( P = 0.01, 0.01), compared with the APS group. Conclusion: This study was able to show that allospacer failure in multi-level ACDF surgery is more common with a longer fusion length, less postoperative T1 slope, and an anterior plate-screws technique. Pedicle screws provided the best biomechanical stability among the 3 constructs.

Mycobacterial periprosthetic joint infection (PJI) is very rare and is generally associated with an immunosuppressive environment. Few large-scale studies of this unusual PJI have been conducted. The current study was performed to assess the clinical features and outcomes following two-stage re-implantation for mycobacterial PJI after primary total knee arthroplasty (TKA). We conducted a retrospective review of data collected from our database involving ten cases of two-stage re-implantation manifesting mycobacterial PJI. Patients were followed for at least five years or until recurrent infection. The mean follow-up duration in patients who remained free of infection was 7.5 years (range 5–9.5 years). Seven patients (70%) belonged to the American Society of Anesthesiologists’ grade 3 or 4. The surgical protocol entailed resection arthroplasty and cement spacer insertion with vigorous debridement, followed by at least six weeks of systemic antimicrobial therapy and delayed re-implantation in all patients. The median duration from resection arthroplasty to re-implantation was 5.3 months (range 2–10.5 months). Following re-implantation, five patients with Mycobacterium fortuitum were treated with amikacin for six weeks and oral clarithromycin for three months. Five patients infected with M. tuberculosis received anti-tuberculosis medications immediately after pathogen isolation, for a period of 12 months. Mycobacterial PJI can be treated successfully via resection arthroplasty and delayed re-implantation combined with proper antimicrobial agents. Suspicious infection or loosening after primary TKA, particularly in an immunosuppressive environment, warrants the attention of an orthopedic surgeon to consider the possibility of unusual PJI.

Background: There are a few biomechanical studies that describe posterior fixation methods with pedicle screws (PS) and lateral mass screws (LMS), the combination of both screw types and their effect on an allograft spacer in a surgically treated cervical segment is unknown. Methods: Finite element model (FEM) analyses were used to investigate the effects of a hybrid technique using posterior PS and LMS. Stress distribution and subsidence risk from a combination of screws under hybrid motion control conditions, including flexion, extension, axial rotation, and lateral bending, were investigated to evaluate the biomechanical characteristics of different six-screw combinations. Findings: The load sharing on the allograft spacer in flexion mode was highest in the LMS model (74.6%) and lowest in the PS model (35.1%). The likelihood of subsidence of allograft spacer on C6 was highest in the screws from the distal LMS (type 5) model during flexion and extension (4.902 MPa, 30.1% and 2.189 MPa, 13.4%). In lateral bending, the left unilateral LMS (type 4) model screws on C5 (3.726 MPa, 22.9%) and C6 (2.994 MPa, 18.4%) yielded the greatest subsidence risks, because the lateral bending forces were supported by the LMS. In counterclockwise axial rotation, the left unilateral LMS (type 4) model screws on C5 (3.092 MPa, 19.0%) and C6 (3.076 MPa, 18.9%) demonstrated the highest subsidence risks. Conclusion: The asymmetrical ipsilateral use of LMS and posterior PS in lateral bending and axial rotation demonstrated the lowest stability and greatest subsidence risk. We recommend bilateral symmetrical insertion of LMS or posterior PS and posterior PS on distal vertebrae for increased stability and reduced risk of allograft spacer subsidence.

There are a few studies on the postoperative changes in sagittal alignment and corresponding factors, including hand grip strength (HGS) and muscle performance tests for lumbar spinal stenosis (LSS). Thus, we aimed to determine whether HGS can be a surrogate marker for global sagittal alignment changes after decompression with fusion surgery for LSS. This retrospective observational study included 91 patients who underwent spine fusion surgery for LSS. Radiological spinopelvic parameters, including sagittal vertical axis (SVA), lumbar lordosis (LL), pelvic tilt (PT), pelvic incidence (PI), global tilt (GT), and T1 pelvic angle (T1PA), were analyzed preoperatively and 1 year after posterior decompression and fusion surgery. To assess muscle performance, the 6-m walk (SMT), timed up and go (TUGT), and sit-to-stand (STS) tests were conducted. The relationship between HGS and postoperative SVA was examined through multiple linear regression analysis. Additionally, the relationship between HGS and preoperative/postoperative radiologic spinopelvic parameters and muscle performance test results was analyzed through Pearson's correlation. HGS was significantly correlated with age, preoperative and postoperative SVA, and the muscle performance tests. Furthermore, HGS was a factor that can significantly influence postoperative SVA changes in multiple linear regression analyses. Therefore, HGS may be a good predictor of postoperative SVA change.

Findings from the published ACHEON study revealed inadequate pain relief for chronic non-cancer pain (CNCP) across 10 Asian countries/regions. Hence, we performed additional analyses on the survey data to understand management practices for relieving CNCP and treatment-related adverse events (AEs). Descriptive statistics were used to summarize patients’ profile, prescribed treatments, and associated AEs. Two-sample t test was used to compare pain levels between treatment groups. Univariate analyses were conducted to identify factors associated with pain intensity, presence of any common AEs, perceived treatment adequacy, patient-physician interaction, and employment status. Of 1305 patients surveyed, the median duration of CNCP was 24 (interquartile range, 39) months. The majority of patients (89.3%) reported having moderate (44.4%) or severe pain (44.9%). Most patients (80.1%) were prescribed non-opioids, while 16.2% of patients were untreated for pain. Although over half of the treated patients (53.8%) experienced AEs while receiving pain treatment, two-fifths were prescribed medications to manage these AEs. High pain levels, presence of AEs, and employment status influenced patients’ perception of treatment adequacy. Patients were more willing to inform their physicians when pain levels were higher and when they perceived sufficient time with physicians. These findings revealed inadequate treatment of CNCP in patients from the participating countries/regions. CNCP management may be improved through increased physician-patient interaction time and adopting a biopsychosocial model for treatment. A proactive and multidimensional approach is required to manage CNCP and potential treatment-related AEs so as to provide optimal care for patients experiencing CNCP.

Purpose The aim of this study was to investigate the effects of relaxin (RLN) expression on fibrosis inhibition in synovial fibroblasts. Materials and methods Tissue cells from patients with knee osteoarthritis and > 30° flexion contractures were utilised. Synovial fibroblasts were activated by TGF-β1 (two nanograms per millilitre) and then exposed to Ad-RLN as a therapeutic gene, adenovirus-lacZ construct as a marker gene, and SB505124 as an inhibitor for TGF-β1 signal for 48 h. The mRNA expression levels of collagens and MMPs were analysed by reverse transcription-polymerase chain reaction. Also, fibronectin, phosphorylation of Smad2 and ERK1/2, alpha smooth muscle actin, TIMP-1, TIMP-2, MMP-1 and MMP-13 levels were estimated using western blotting, and the total collagen synthesis was assayed. Results Ad-RLN-transduced synovial fibroblasts demonstrated 17%, 13%, and 48% reduction in collagen I, III and IV mRNA expression levels, respectively, and a 40% decrease in MMP-3, MMP-8, 20% decrease in MMP-9, MMP-13 mRNA expression, compared to non-Ad-RLN-transduced cells. In protein expression, Ad-RLN-transduced synovial fibroblasts demonstrated 46% increase in MMP-1, 5% decrease in MMP-2, 51% increase in MMP-9, and 22% increase in MMP-13, compared to non-Ad-RLN-transduced cells. Ad-RLN-transduced synovial fibroblasts showed a 25% decrease in TIMP-1 and 65% decrease in TIMP-2 protein expression at 48 h, compared to non-Ad-RLN-transduced cells. Ad-RLN-transduced synovial fibroblasts demonstrated a 45% inhibition of fibronectin in protein expression level and 38% decrease in total collagen synthesis at 48 h, compared to non-Ad-RLN-transduced cells. Conclusion Relaxin expression exerted anti-fibrogenic effects on synovial fibroblasts from patients with knee osteoarthritis and flexion contractures. Therefore, relaxin could be an alternative therapeutic agent during the initial stage of osteoarthritis with flexion contracture by exerting its anti-fibrogenic effects.

Study design Retrospective observational and case-control study. Objective To determine the risk factors for progression of degenerative listhesis by comparing patients with and without progression at greater than 5-year follow-up. Summary of background data The previous study with 2- to 7-year follow-up showed that degenerative spondylolisthesis of the cervical spine did not progress. Longer-term follow-up may reveal that these patients actually do progress over time. Methods We identified 218 patients with greater than 5-year follow-up without surgery. They were categorized as either having or not having cervical spondylolisthesis. We defined spondylolisthesis as the presence of greater than 2 mm of translation in standing neutral lateral radiographs of the cervical spine at the initial evaluation. The control group at baseline was those without spondylolisthesis. Progression of translation was defined as greater than 2 mm of additional translation on the final standing neutral radiograph. Results The mean follow-up duration was 6.4 ± 1.0 years (range: 5-9.4 yr). Progression of translation was found in 20 patients (9.2%), including 4 patients in the spondylolisthesis group and 16 patients in the control group. Progression of translation was not related to the presence of spondylolisthesis or the severity of translation at the initial evaluation, but was more common in the elderly and in the patients with anterior translation than those with posterior translation at the initial evaluation. In addition, progression of spondylolisthesis was not correlated with any change of symptoms. Conclusion Progression of cervical spondylolisthesis is not related to the presence of spondylolisthesis at baseline. Level of evidence 4.

Patient-reported outcomes (PROs) provide practical guides for treatment; however, studies that have evaluated PROs of women in Korea with postmenopausal osteoporosis (PMO) are lacking. This cross-sectional, multi-center (29 nationwide hospitals) study, performed from March 2013 to July 2014, aimed to assess PROs related to treatment satisfaction, medication adherence, and quality of life (QoL) in Korean PMO women using osteoporosis medication for prevention/treatment. Patient demographics, clinical characteristics, treatment patterns, PROs, and experience using medication were collected. The 14-item Treatment Satisfaction Questionnaire for Medication (TSQM) (score-range, 0-100; domains: effectiveness, side effects, convenience, global satisfaction), Osteoporosis-Specific Morisky Medication Adherence Scale (OS-MMAS) (score-range, 0-8), and EuroQol-5 dimensions questionnaire (index score range, - 0.22 to 1.0; EuroQol visual analog scale score range, 0-100) were used. To investigate factors associated with PROs, linear (treatment satisfaction/QoL) or logistic (medication adherence) regression analyses were conducted. A total of 1804 patients (age, 62 years) were investigated; 60.1% used bisphosphonate, with the majority (67.2%) using weekly medication, 27.8% used daily hormone replacement therapy, and 12.1% used daily selective estrogen receptor modulator. Several patients reported gastrointestinal (GI) events (31.6%) and dental visits due to problems (24.1%) while using medication. Factors associated with the highest OS-MMAS domain scores were convenience and global satisfaction. GI events were associated with non-adherence. TSQM scores for effectiveness, side effects, and GI risk factors were significantly associated with QoL. Our study elaborately assessed the factors associated with PROs of Korean PMO women. Based on our findings, appropriate treatment-related adjustments such as frequency/choice of medications and GI risk management may improve PROs.

Spinal surgeries are often associated with a high incidence of perioperative blood loss, which poses several complications. Much current research focuses on the importance of antifibrinolytic drugs during spinal surgeries to reduce blood loss, which can also reduce the risk of the need for blood transfusions. We evaluated the effects of prophylactic, low-dose tranexamic acid (TXA) in spinal fusion surgeries on blood loss, blood transfusions, and associated complications.TXA was administered to 90 patients at a constant infusion rate of 10 mg/kg for 20 minutes after anesthesia induction, followed by a maintenance dose of 1 mg/kg/h until the end of the operation. An additional 91 patients were included as controls.There were no significant differences between the study groups in terms of intraoperative blood loss, which was 500 mL for both groups (We confirmed that low dose TXA has no effect on intraoperative blood loss volume or blood transfusion requirements and that it can significantly reduce the need for postoperative blood transfusions.

Study design A retrospective study. Objective To identify preoperative risk factors causing cervical fifth nerve root palsy (C5 palsy) after laminectomy and fusion (LF). Summary of background data It is well known that postoperative C5 palsy is not rare after cervical surgery. Although there remains controversy, C5 palsy is considered to be more common in patients who had LF than in those who had laminoplasty. However, the reason for the higher incidence of C5 palsy in patients with LF has been poorly understood. Methods A total of 70 consecutive patients (mean age: 60.3 y) who had LF due to cervical myelopathy were reviewed. Patients were divided on the basis of the presence (group P) or absence (group N) of C5 palsy. Among various risk factors for C5 palsy from previous reports, 6 risk factors were selected as follows: (1) preoperative low Japanese Orthopedic Association score, (2) postoperatively increased lordosis, (3) low Pavlov ratio, (4) high signal intensity in the cord at C3-C5, (5) anterior protruding mass lesion compressing the spinal cord, and (6) presence of C4-C5 foraminal stenosis. With these factors, the 2 groups were compared by statistical analysis. Results C5 palsy occurred in 10 patients (14.3%). The mean onset time was 3.5 days (range, 1-8 d) and the mean recovery time was 3.4 months (range, 1-7 mo). There were no significant differences in the preoperative Japanese Orthopedic Association score, cervical lordosis, Pavlov ratio, high signal intensity, and anterior protruding mass between the 2 groups (P>0.05). However, C4-C5 foraminal stenosis was found in 80.0% (8/10) in group P and 21.7% (13/60) in group N. There were significant differences between the 2 groups in C4-C5 foraminal stenosis (P=0.004). Conclusions In this study, a high occurrence rate and risk factor for C5 palsy were verified after LF. Among the various factors, C4-C5 foraminal stenosis was the only risk factor for C5 palsy. Preoperative warning for C5 palsy after LF seems to be imperatively necessary, especially in patients with C4-C5 foraminal stenosis.

Purpose To demonstrate the impact of correcting sagittal balance (SB) on functional outcomes of surgical treatment for degenerative spinal disease and actual falls via utilization of new minimally invasive lumbar fusion techniques via a lateral approach. Materials and methods From November 2011 to March 2015, we enrolled 56 patients who underwent minimally invasive lateral lumbar interbody fusion (LLIF) and matched 112 patients receiving decompression/postero-lateral fusion (PLF) surgery for lumbar spinal stenosis. According to SB status using C7-plumb line-distance (C7PL) and surgery type, patients were divided into three groups: SB PLF, sagittal imbalance (SI) PLF, and LLIF groups. We then compared their outcomes. Results The mean C7PL was 6.2±13.6 mm in the SB PLF group, 72.9±33.8 mm in the SI PLF group, and 74.8±38.2 mm in the LLIF group preoperatively. Postoperatively, C7PL in only the LLIF group improved significantly (p=0.000). Patients in the LLIF group showed greater improvement in fall-related functional test scores than the SI PLF group (p=0.007 for Alternate-Step test, p=0.032 for Sit-to-Stand test). The average number of postoperative falls was 0.4±0.7 in the SB PLF group, 1.1±1.4 in the SI PLF group, and 0.8±1.0 in the LLIF group (p=0.041). Oswestry Disability Index and the Euro-QoL 5 dimension visual analogue scale scores also showed greater improvements in the LLIF group than in the SI PLF group at postoperative 1 year (p=0.003, 0.016). Conclusion Surgical correction of SI in patients with lumbar spinal stenosis using a combination of minimal invasive LLIF and posterior surgery achieved better surgical outcomes and a lower incidence of actual falls than PLF surgery.

The goal of this study was to reassess serum alkaline phosphatase (ALP) as tumor marker in osteosarcoma. We retrospectively examined serum ALP levels at diagnosis, every therapeutic step (neoadjuvant chemotherapy, surgery, and adjuvant chemotherapy), metastasis, and follow-up and analyzed the role of ALP as tumor marker in 210 osteosarcomas. The diagnostic performances of ALP were validated with pathology-proven 899 other primary bone lesions. Elevated ALP at diagnosis was associated with inferior overall survival (OS) (Log Rank P < 0.001) and disease-free survival (Log Rank P = 0.005) and independently significant for OS in multivariate analysis (hazard ratio [HR]=2.12, P = 0.032). During therapy, the ALP level significantly changed according to therapeutic steps (P < 0.001 for patients >= 15 years old, P < 0.001 for patients >= 15 years old) and survival (P = 0.015 for >= 15 years, P = 0.002 for >= 15 years), and the response of ALP to therapy and survival were associated (P = 0.042 for >= 15 years, P = 0.036 for >= 15 years). Initial ALP level was linearly correlated with tumor burden (total tumor volume; P = 0.016 for >= 15 years, bone tumor volume; P = 0.012 for >= 15 years). The sensitivity and specificity of ALP on diagnosis were 53.2% (95% Confidence Interval [CI]: 0.475-0.586) and 90.1% (95% CI: 0.888-0.913). The sensitivity of ALP on metastasis was 53.2% (95% CI: 0.431-0.624), and the specificity was 78.2% (95% CI: 0.720-0.839) at15 months postoperative and 90.0% (95% CI: 0.824-0.952) at 3 years postoperative. Serum ALP was found to be a valuable tumor marker with high specificity in osteosarcoma.

BACKGROUND CONTEXT There has been limited research on the association between hand grip strength (HGS) as one of the diagnostic criteria for sarcopenia and surgical outcomes of lumbar spinal stenosis (LSS). PURPOSE We aimed to determine the effect of HGS on surgical outcomes and risk of fall in patients with LSS. STUDY DESIGN This is a retrospective observational study. PATIENT SAMPLE We included 200 patients who underwent spinal surgery for LSS. OUTCOME MEASURES We recorded clinical outcome parameters, including Oswestry Disability Index (ODI), Euro-QOL (EQ-5D), and visual analog scale (VAS) scores for back or leg pain. To assess the risk of fall we used HGS and four functional mobility tests (alternative step test, six-meter walk test, timed up and go test, sit-to-stand test). MATERIALS AND METHODS ODI, EQ-5D, and VAS scores for back and leg pain were assessed preoperatively and 1 year after surgery. The four functional mobility tests were assessed at each time point during the 1-year follow-up period to assess the risk of fall in patients with LSS. We divided the patient cohort according to sex and allocated them into two different groups based on HGS: high HGS (≥26 kg for men, n=26; ≥18 kg for women, n=35), and low HGS ( RESULTS In women and men, HGS correlated with the preoperative/postoperative ODI (r1=−0.217/r2=−0.345 in women, and r1=−0.384/r2=−0.411 in men) and EQ-5D scores (r1=0.190/r2=0.309 in women, and r1=0.373/r2=0.467 in men). HGS also correlated with the four postoperative results for the functional mobility tests: alternative step test (r=−0.238 in women, r=−0.431 in men), six-meter walk test (r=−0.232 in women, r=−0.282 in men), timed up and go test (r=−0.285 in women, r=−0.359 in men), and sit-to-stand test (r=−0.238 in women, r=−0.251 in men). The preoperative and postoperative ODI and EQ-5D scores in the high HGS group were superior to those in the low HGS group. Among the four functional mobility tests, preoperative and postoperative six-meter walk test results showed improvements in the high HGS group. CONCLUSIONS Considering the multifactorial nature of falls, HGS may be a useful surrogate marker for predicting the risk of falls and clinical outcomes in patients with LSS.

Purpose: We have always used the standard anatomical landmark vertebrae to measure the sagittal alignment. Instead, scoliosis has been evaluated by the end vertebrae in the coronal plane. There have been clinical studies to investigate sagittal alignment on the end vertebrae of inflection points (IPs). The purpose is to determine sagittal alignment based on IPs and to elucidate the changes while considering age groups. Methods: We identified the most titled vertebrae in the sagittal plane to define the end vertebrae of S1, thoracolumbar and cervicothoracic IPs and to measure the Cobb angles of sacral slope, functional lumbar, thoracic, cervical segment between them, and the McGregor’s line, and the IP distances from the C2 plumb line to the point bisecting the upper end plate of the IPs, in addition to S1. Results: The most common thoracolumbar and cervicothoracic IPs were L2 and T1, respectively. However, the next most common cervicothoracic IP changed from T2 in the youngest to C7 in the oldest age group. The sagittal angles decreased at the sacral slope and functional lumbar segment but not the functional thoracic segment and functional cervical segment. Similarly, the distance increased at the C2 sagittal vertical axis (SVA) distance to S1 and thoracolumbar IP distance but not at the cervicothoracic IP distance. There was no difference in the pelvic incidence among age groups. Conclusion: The sagittal Cobb angles based on the IPs decreased at the sacral slope and functional lumbar segment in the older adults. Consequently, the C2 SVA distance to S1 and thoracolumbar IP distance increased.

Interest in intraoperative stress has increased due to its potentially detrimental impact on surgical performance and burnout among spine surgeons.The purpose of this study was to analyze intraoperative stress in real time in terms of electroencephalography signals and heart rate variability using a wearable device during spine surgery.Prospective observational study.Five orthopedic spine surgeons with experience ranging from 1 to 30 years were included.The outcome measures included stress levels among the spine surgeons and differences in stress parameters between novice and expert surgeons and between assistants and operators.From June 2018 to November 2018, 179 consecutive records of intraoperative stress measures, including intraoperative electroencephalography signals and heart rate variability, comprising beats per minute (BPM) and low frequency/high frequency ratio, for the orthopedic spine surgeons were prospectively gathered, compared, and analyzed.Among all measures, sensory-motor rhythm (SMR) waves, gamma waves, and BPM differed significantly during surgery (analysis of variance; p=.040, .013, .002, respectively). Surgery duration and intraoperative bleeding were positively correlated with stress parameters, including gamma waves and tension. For operators, surgeon experience was negatively correlated with concentration, tension, and SMR, gamma, M-beta, and H-beta waves (Pearson correlation, p.05). However, for assistants, surgeon experience was positively correlated with concentration, tension, BPM, and SMR, M-beta, H-beta, and gamma waves. Bleeding amounts were correlated positively with gamma waves and tension for both operators and assistants (Pearson correlation, p.05). Stress among operators was higher than that among assistants in terms of low frequency/high frequency ratio.Operators and surgeons with low experience exhibited higher stress levels during surgery, which should be addressed when scheduling elective surgery to ensure optimal conditions among spine surgeons.

Background The purpose of this study is to investigate effects of different fixation methods on the physical stress on allospacers, endplate-vertebral body, and implants using finite element model analyses. Methods Stress distribution and subsidence risk according to the fixation methods under the condition of hybrid motion control were analyzed. The detailed finite element model of a previously validated, three-dimensional, intact cervical spinal segment model, with C5–C6 segmental fusion using allospacer, was used to evaluate the biomechanical characteristics of different fixation combinations, such as anterior plate/screws, lateral mass screw, and posterior pedicle screw. Findings The load sharing on allospacers increased in extension in order of posterior pedicle screws (21.4%), lateral mass screws (31.5%), and anterior plate/screws (56.6%). lateral mass screw demonstrated the highest load sharing (68.1%) on the allospacer in flexion. The Peak von Mises stress of the allospacer was the lowest in flexion and axial rotation but the highest in extension with anterior plate/screws. Allospacer subsidence risk was the lowest in extension, lateral bending, and axial rotation with posterior pedicle screws but the lowest in flexion with anterior plate/screws. The bone-screw loosening risk was the lowest in all modes with posterior pedicle screws but the highest with anterior plate/screws. Interpretation Posterior pedicle screws demonstrated the best mechanical stability of allospacer failure-subsidence and the lowest risk of screw loosening. Different motion restrictions depending on the fixation method should be considered for implant and allospacer safety.

Patellar impingement on tibial polyethylene (PIP) is one potential complication of total knee arthroplasty (TKA). When PIP occurs, it is often related to inaccurate restoration of the joint line or due to soft-tissue contracture. We investigated the prevalence and etiology of PIP in Asian patients with deeply flexed knees following posterior stabilized (PS)-TKA. We retrospectively reviewed 54 patients (65 knees) with PIP after primary PS-TKAs without patellar resurfacing performed between 2008 and 2011. These patients were compared with a group of 124 patients (130 knees) without PIP matched for age, sex, and body mass index (BMI). The minimum follow-up was 5 years (range, 5–8.1 years). Patients were evaluated by blinded, independent observers using the Oxford knee score, the Waters score, and radiographic parameters. Impingement between the patella and the tibial polyethylene had a mean onset of 13.5 months after PS-TKA. The development of PIP was significantly associated with change in patellar tendon length (odds ratio [OR] = 11.4, 95% confidence interval [CI]: 11.2–11.6%), shorter postoperative patellar tendon length (OR = 2.1, 95% CI: 1.8–2.5%), change in the Insall–Salvati ratio (OR = 0.9, 95% CI: 0.8–1.0%), and joint line elevation (OR = 5.3, 95% CI: 4.8–5.8%) on multiple logistic regression analysis. Our findings reinforce the importance of accurate joint line restoration and the avoidance of iatrogenic injury to the patellar tendon, which can lead to shortening of the patellar tendon. This is a retrospective comparative study and its level of evidence is III.

The efficacy of once-weekly risedronate with and without cholecalciferol in bone mineral density (BMD) in Korean patients with osteoporosis was compared. After 12 months, both spine and hip BMD increased significantly in both groups, but there was no significant difference between two groups. This study investigated the efficacy and safety of once-weekly risedronate with and without cholecalciferol in BMD in Korean patients with osteoporosis. This was a prospective, 12-month, randomized, open-labeled, actively controlled trial involving 41 hospitals. A total of 841 subjects with osteoporosis were randomized to once-weekly risedronate (35 mg) and cholecalciferol (5600 IU) in a single pill (RSD+, n = 642) or once-weekly risedronate (35 mg) alone (RSD, n = 199). BMD was measured via dual-energy X-ray absorptiometry at the lumbar spine and hip, and the serum levels of 25-hydroxy vitamin D (25(OH) D), parathyroid hormone (PTH), and alkaline phosphatase (ALP) were assayed at baseline and after 12 months of treatment. After 12 months, the lumbar spine, femoral neck, and total hip BMD increased significantly in both groups; there was no significant difference between two groups. Women in the RSD+ group exhibited significantly increased lumbar spine BMD, and subjects with previous fracture history in the RSD+ group had significantly increased total hip BMD compared with the RSD group. The serum 25(OH) D level increased significantly in the RSD+ group. The serum PTH level decreased in the RSD+ group but increased in the RSD group. The serum ALP level significantly decreased in both groups; there was no significant difference between two groups. A once-weekly pill containing risedronate and cholecalciferol had the equivalent antiresorptive efficacy on BMD compared with risedronate alone and improved 25(OH) D serum levels after 12 months of treatment without significant adverse events in Korean patients with osteoporosis.

Background: Few studies have investigated associations between hand grip strength (HGS) and the surgical outcomes of degenerative cervical myelopathy (DCM). Methods: This study was designed as a prospective observational study of 203 patients who had undergone fusion surgery for DCM. We divided the patients according to sex and HGS differences. Clinical outcome parameters, including HGS, a fall diary and four functional mobility tests (alternative step test, six-meter walk test, timed up and go test, and sit-to-stand test) were measured preoperatively, at 3 months and 1 year after surgery. Results: Mean patient ages were 59.93 years in the male group and 67.33 years in the female group (p = 0.000, independent t-test). The mean HGS of both hands improved significantly at postoperative 3 months and 1 year in all patients (p = 0.000 for both, ANOVA). In male patients, preoperative risk of falls was negatively correlated with HGS (p = 0.000). In female patients, pre- and postoperative risk of falls were correlated negatively with HGS (p = 0.000). The postoperative incidence of falls decreased in both groups (p = 0.000) Conclusions: Postoperative HGS in patients with DCM is correlated with postoperative falls and functional outcome differently, when comparing male and female patients, for predicting favorable outcomes and neurologic deficit recovery after surgery in DCM patients.

It has been reported that good spinal sagittal alignment reduces the risk of fall and positive sagittal balance is the radiographic parameter that is most highly correlated with adverse health outcomes. However, no reports have demonstrated a change in risk of falling in patients with lumbar spinal stenosis (LSS) according to sagittal balance status.From September 2013 to October 2014, 141 patients who underwent lumbar spine surgery, including decompression and fusion in-situ for LSS, were enrolled in this study. Based on sagittal balance status, patients were divided into sagittal balance (SB) and sagittal imbalance (SI) groups. Four functional mobility tests were used to evaluate the risk of falling, and a fall diary, Oswestry disability index (ODI), and the Euro-QoL 5D(EQ-5D) visual analogue scale (VAS) were utilized to assess clinical improvement.The mean patient age was 70.1 years in the SB group (N=46) and 70.9 years in the SI group (N=95) (not significant). The mean C7PL was 7.9mm in the SB group and 66.1mm in the SI group preoperatively (p0.05). Among the four functional tests, only postoperative SMT and STS improved significantly in the SB group (p0.05). Patients in the SI group showed significantly improved scores for all four functional tests during postoperative follow-up (p0.05), but their performance was still worse than patients in the SB group. Average number of falls per individual during the follow-up period was 1.1±2.5 in the SB group and 1.9±3.2 in the SI group (p0.05). There was a significant difference in the distribution of non-fallers and fallers (single and multiple fallers) between the two groups postoperatively(p0.05). ODI and the EQ-5D VAS showed greater improvement in the SB group than the SI group. Multiple regression analysis revealed that sagittal balance during follow-up significantly affected ODI, EQ-VAS, functional mobility tests. (p0.05).Therefore, when fusion surgery is planned in patients with LSS, careful consideration of sagittal balance status might be important to attain better surgical and functional outcomes and decrease the incidence of actual falls after surgical treatment.

Vitamin D has received considerable attention in recent years owing to the increasing evidence of its importance in muscle function and physical performance. The present study attempted to determine whether patients with low serum vitamin D levels had impairment in early functional outcomes following total knee arthroplasty (TKA). This was a prospective cohort study that included 92 patients. Patients were divided into two groups according to their vitamin D levels as assessed at the preoperative visit: (1) vitamin D-deficient group, serum 25-hydroxyvitamin D3 (25(OH)D) levels

Background Context Although the simultaneous management of neuronal ischemia-related pain and compression-demyelination–related neuropathic pain is considered optimal in treating lumbar spinal stenosis (LSS), the effect of combination therapy with pregabalin and limaprost has not been elucidated. Purpose This study aimed to compare the effects of limaprost and pregabalin individually and in combination for the treatment of LSS. Study Design This is a prospective, double-blind, double-dummy, randomized controlled trial. Patient Sample The sample consists of patients with LSS. Outcome Measures The baseline-adjusted Oswestry Disability Index (ODI) score, visual analog scale (VAS) scores for leg pain, the European Quality of Life-5 dimensions (EQ-5D), and initial claudication distance (ICD). Methods The present study ( ClinicalTrials.gov , number NCT01888536) was a prospective, double-blind, double-dummy, randomized controlled trial designed to determine the efficacy of limaprost in alleviating leg pain, improving disability, and increasing walking distance in persons with degenerative LSS in three different treatment groups: limaprost alone, pregabalin alone, and combined limaprost and pregabalin through 1:1:1 allocation. The primary outcome was the baseline-adjusted ODI score at 8 weeks after treatment. The non-inferior margin of the ODI was set at δ=10 points. Results The baseline-adjusted ODI score (primary outcome) at 8 weeks after treatment in the limaprost group was not inferior to those in the pregabalin and limaprost+pregabalin groups. The overall changes of the baseline-adjusted ODI scores, VAS scores for leg pain, the EQ-5D, and ICD during the follow-up assessments over an 8-week period (secondary end point) were not different among the three groups. The baseline-adjusted ODI scores and VAS scores for leg pain decreasedsignificantly over time after treatment in all three groups. The baseline-adjusted EQ-5D score and ICD also increased significantly over time after treatment in all three groups. Conclusions The efficacy of limaprost for lumbar spinal stenosis was not inferior compared with that of pregabalin or the combination of limaprost and pregabalin in terms of disability. Therefore, combined treatment with limaprost and pregabalin does not provide additional relief in symptoms in patients with LSS compared with monotherapy with limaprost or pregabalin.

BACKGROUND To assess the cost-effectiveness of drug therapy to prevent osteoporotic fractures in postmenopausal women with osteopenia in Korea. METHODS A Markov cohort simulation was conducted for lifetime with a hypothetical cohort of postmenopausal women with osteopenia and without prior fractures. They were assumed to receive calcium/vitamin D supplements only or drug therapy (i.e., raloxifene or risedronate) along with calcium/vitamin D for 5 years. The Markov model includes fracture-specific and non-fracture specific health states (i.e. breast cancer and venous thromboembolism), and all-cause death. Published literature was used to determine the model parameters. Local data were used to estimate the baseline incidence rates of fracture in those with osteopenia and the costs associated with each health state. RESULTS From a societal perspective, the estimated incremental cost-effectiveness ratios (ICERs) for the base cases that had T-scores between -2.0 and -2.4 and began drug therapy at the age of 55, 60, or 65 years were $16,472, $6,741, and -$13,982 per quality-adjusted life year (QALY) gained, respectively. Sensitivity analyses for medication compliance, risk of death following vertebral fracture, and relaxing definition of osteopenia resulted in ICERs reached to $24,227 per QALY gained. CONCLUSIONS ICERs for the base case and sensitivity analyses remained within the World Health Organization's willingness-to-pay threshold, which is less than per-capita gross domestic product in Korea (about $25,700). Thus, we conclude that drug therapy for osteopenia would be a cost-effective intervention, and we recommend that the Korean National Health Insurance expand its coverage to include drug therapy for osteopenia.

Purpose The present study aimed to identify the physiological characteristics of cells by investigating the change in gene expression and protein levels during extracellular matrix (ECM) synthesis in the intervertebral disc (IVD) under hypoxic conditions. Materials and methods To test the effect of oxygen on cell growth and ECM synthesis of chondrocyte-like cells, the cells from IVD were separated and cultured in two hypoxia-mimicking systems: chemical hypoxic conditions using deferoxamine (DFO), and physiological hypoxic conditions using a hypoxic chamber for 7 days. Chondrocyte like cells cultured without DFO and under the normal oxygen concentration (21% O₂ and 5% CO₂, 37°C) served as the controls. Results Chondrocyte-like cells cultured in the presence of 6% oxygen demonstrated a 100% increase in cellular proliferation compared to the control. The cells treated with chemical hypoxic conditions demonstrated a dose-dependent increase in the mRNA expression of glucose transporter-1, GAPDH, aggrecan, and type II collagen on Day 1. When treated with 100 µM DFO, the cells showed a 50% increase in the levels of proteoglycan protein on Day 7. The cells treated with chemical hypoxic condition demonstrated increase in sulfated glycosaminoglycan (GAG) protein levels on Day 7. Moreover, the cells cultured in the presence of 6% oxygen showed a 120% increase in sulfated GAG levels on Day 7. Conclusion The oxygen concentration had an important role in the viability, proliferation, and maturation of chondrocyte-like cells in IVD. In addition, chondrocyte-like cells are sensitive to the concentration of oxygen.

Rationale: Emphysematous osteomyelitis is a rare disease caused by gas-forming bacteria. But only 45 cases have been reported in the literature since then. Patient concerns: A 72-year-old female presented to our hospital with severe lower back pain that aggravated 4 days ago. Diagnoses: Computed tomography (CT) revealed intraosseous mottled air in the T12 and L1 vertebral bodies and epidural space. The enhanced T1 and T2 magnetic resonance imaging scans showed heterogeneous signal intensity of vertebral bodies, suggestive of emphysematous osteomyelitis. Interventions: Surgery was performed to identify culture strains and to remove emphysematous lesions of the vertebral body using extensive transpedicular irrigation. Outcomes: Escherichia coli (E coli) was identified in the surgical specimen, and intravenous antibiotic therapy was continued with cefotaxime. The patient had a significant decrease in lower back pain after the surgery and the final CT scan before discharge revealed significantly decreased air at T12 and L1 vertebral bodies and no air density in the epidural space. Lessons: We present a patient diagnosed with emphysematous osteomyelitis in vertebral bodies caused by E coli and successfully treated with surgical intervention.

Background Comparative studies of the biomechanical effects of plates of varying lengths and different screw insertion angles on allograft spacers are lacking. Methods Finite element model analysis of a previously validated, three-dimensional, intact cervical spinal segment model of C3–6 was conducted in the present study. On the C5–6 segment, anterior discectomy and fusion were performed using allograft spacers and different combinations of anterior plates and screws. The biomechanical characteristics of combinations of short, medium, and maximal length plates with screw insertion angles of 0°, 8°, 16°, and 32° were analyzed. Findings In flexion and extension, the risk of allograft spacer subsidence decreased as screw angles increased. Short plates with a screw insertion angle of 32° posed the lowest subsidence risk, similar to medium length plates with a screw insertion angle of 16°, in all motion conditions. The risk of bone yielding increased as plate length increased, but decreased as the screw insertion angle increased. Interpretation Short plates with a large screw insertion angle (32°) showed the highest mechanical stability and load sharing of allograft spacers and the lowest risk of screw loosening. Accordingly, we recommend the use of a short plate and large screw insertion angle for anterior cervical discectomy and fusion.

Objective The reoperation rate after lumbar degenerative disease surgery is low. It is difficult to find statistical differences in reoperation rates according to the different diagnoses of lumbar degenerative diseases. National population-based database overcomes the statistical problem by its large cohorts with longitudinal follow-up in a nation. The purpose was to compare the reoperation rates after single-level lumbar spinal posterior decompression and fusion surgeries depending on different preoperative diagnoses of lumbar degenerative disease. Patients and methods: We used the Korean Health Insurance Review & Assessment Service national database. The study population was the patients with a diagnosis of a degenerative lumbar disease who underwent single-level decompression and fusion from January 1, 2011, to June 30, 2016. We classified the patients into one of three groups based on diagnosis codes of lumbar disc herniation, spondylolisthesis, or spinal stenosis. A reoperation was defined as repeated decompression and fusion. We considered age, sex, the presence of diabetes, osteoporosis, associated comorbidities, and hospital types as potential confounding factors. Results The reoperation rate was higher in patients with spinal stenosis than in those with lumbar disc herniation. However, there was no difference in the reoperation rate between the patients with lumbar disc herniation and those with spondylolisthesis. Male gender and hospital type were risk factors for reoperation. Conclusion The incidence of reoperation was dependent on the diagnostic subgroups of lumbar degenerative diseases. This information can help surgeons accurately communicate with their patients and enhance the preoperative informed consent process.

Study design This was a retrospective cohort study. Objective To evaluate the sagittal alignment and T1 slope after multilevel posterior cervical fusion surgery depending on the distal fusion level; C7 or T1, and find out the appropriate distal fusion level. Summary of background data The sagittal balance of the cervical spine is known to be affected by cervical lordosis and T1 slope. However, T1 slope is not a constant parameter that can be frequently changed after the surgery. Furthermore, useful studies to help guide surgeons in decision-making as to the most appropriate distal level of fusion for cervical sagittal balance are very limited. Materials and methods From 2014 to 2015, 50 patients who underwent multilevel posterior cervical fusion surgery were evaluated and followed up for >2 years. Group 1 was composed of 29 patients whose distal fusion level was C7. Group 2 was composed of 21 patients whose distal fusion level was T1. C1-C2 lordosis, C2-C7 lordosis, C2-C7 sagittal vertical axis (SVA), and T1 slope were measured on preoperative and the last follow-up. Results In group 1, C2-C7 SVA (23.1→30.4 mm, P=0.043) was worsened, and T1 slope (22.3→32.9 degrees, P=0.001) was increased after the surgery. In group 2, no significant change occurred in C2-C7 SVA after the surgery (25.3 →23.6 mm, P=0.648). The last follow-up T1 slope was similar with preoperative T1 slope (22.7→21.8 degrees, P=0.04) in group 2. Conclusions This study showed that sagittal alignment became worse after the multilevel posterior cervical surgery when distal fusion level was stopped at C7, which was associated with increase of T1 slope. However, when we extended the distal fusion level to T1, T1 slope was not changed after the surgery. Therefore, sagittal alignment was maintained after the surgery. On the basis of the results of this study, we recommend distal fusion extends to T1. Level of evidence Level III.

There is a low incidence of reoperation after surgery. It is difficult to detect statistical differences between reoperation rates of different lumbar fusion surgeries. National population-based databases provide large, longitudinally followed cohorts that may help overcome this challenge. The purpose is to compare the repeat decompression and fusion rate after surgery for degenerative lumbar diseases according to different surgical fusion procedures based on national population-based databases and elucidate the risk factor for repeat decompression and fusions. The Korean Health Insurance Review & Assessment Service database was used. Patients diagnosed with degenerative lumbar diseases and who underwent single-level fusion surgeries between January 1, 2011, and June 30, 2016, were included. They were divided into two groups based on procedure codes: posterolateral fusion or posterior/transforaminal lumbar interbody fusion. The primary endpoint was repeat decompression and fusion. Age, sex, the presence of diabetes, osteoporosis, associated comorbidities, and hospital types were considered potential confounding factors. The repeat decompression and fusion rate was not different between the patients who underwent posterolateral fusion and those who underwent posterior/transforaminal lumbar interbody fusion. Old age, male sex, and hospital type were noted to be risk factors. The incidence of repeat decompression and fusion was independent on the fusion method.

Objective The treatment of atrophy or increased fat infiltration of the lumbar paraspinal muscles of patients with back pain, lumbar radiculopathy, or lumbar degenerative kyphosis is controversial. We review the literature on changes in the lumbar paraspinal muscles of these patients. Methods We searched Medline for relevant English-language articles and retrieved 25 articles published from 1993 to 2017 on changes in the lumbar paraspinal muscles; 21 met our study criteria. We categorized each article into three groups: randomized clinical trial, nonrandomized prospective study, or retrospective study. Results We found 1 randomized prospective, 3 nonrandomized prospective, and 17 retrospective studies. Atrophies of the multifidus muscle are found at the level of the L5 vertebral body in patients with back pain, lumbar radiculopathy, and lumbar degenerative kyphosis. Increased fat infiltration to the multifidus muscle was found in the patients with lumbar radiculopathy or lumbar degenerative kyphosis. However, there are controversies over fat infiltration to the multifidus muscle in the patients with back pain and the efficiency of a paramedian surgical approach to prevent the atrophy of the multifidus muscle. Conclusions Atrophy of the multifidus muscle was found in patients with back pain, lumbar radiculopathy, and lumbar degenerative kyphosis. There was increased fat infiltration to the multifidus muscle in those patients with lumbar radiculopathy or lumbar degenerative kyphosis.

STUDY DESIGN: Retrospective evaluation. PURPOSE: To analyze the effect of T1 slope on degree of degeneration in patients with cervical disc degeneration. OVERVIEW OF LITERATURE: The T1 slope is well known parameter that may be very useful in evaluating sagittal balance. There are no reports on the analysis of the relationship between T1 slope and cervical disc degeneration. We hypothesized that T1 slope has an effect on the degree of cervical degeneration. METHODS: Sixty patients who had cervical spine magnetic resonance imaging (MRI) in our orthopedic clinic were enrolled. Patients were divided into two groups according to T1 slope. Radiologic parameters obtained from radiography and cervical spine MRI were compared between low T1 slope group (≤25) and high T1 slope group (>25). RESULTS: Among low T1 slope group, average degeneration grade of each cervical segment was 2.65 in C2-3, 2.50 in C3-4, 2.62 in C4-5, 3.23 in C5-6, and 2.81 in C6-7. And that of high T1 group was 2.35 in C2-3, 2.32 in C3-4, 2.59 in C4-5, 2.79 in C5-6, and 2.32 in C6-7. Grade of degeneration of low T1 group was significantly higher, as compared with high T1 group in C5-6 (p=0.028) and C6-7 (p=0.009). Percentage of high grade degeneration of more than grand III was 65.4% in low T1 group and 32.4% in high T1 group (p=0.018). Risk of high grade degeneration of C6-7 was significantly higher in low T1 group (odds ratio, 5.63; 95% confidence interval, 1.665-19.057; p=0.005). CONCLUSIONS: Patients with low T1 slope had higher grade of degeneration regardless of age and gender. Low T1 slope is a potential risk factor of cervical spondylosis especially in the C6-7 cervical segment.

Study Design Retrospective study. Purpose To evaluate the effect of intraoperative wound application of vancomycin on preventing surgical wound contamination during instrumented lumbar spinal surgery. Overview of Literature Postoperative infection is the one of the most devastating complications of lumbar surgery. There are a few reports showing the benefits of intraoperative wound application of vancomycin during spinal surgery. However, there is no report about the effectiveness of local vancomycin instillation in prevention of surgical wound contamination. Methods Eighty-six patients underwent instrumented lumbar spinal surgery. Mean patient age was 65.19 years (range, 23-83 years). There were 67 females and 19 males. During surgery, vancomycin powder was applied into the surgical site before closure in 43 patients (antibiotic group) and vancomycin powder was not applied into the surgical site before closure in 43 patients (control group). The tip of the surgical drain was cultured to evaluate surgical wound contamination. Erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured on the first, third, seventh, and fourteenth day after the operation. Results We found two patients with a positive culture from the tip of surgical drains in the antibiotic group, and one patient with a positive culture from the tip of the surgical drain in the control group. Postoperative ESR and CRP levels did not show significant differences between the two groups. On the third postoperative day, ESR in patients of the antibiotic group was more significantly decreased than that in patients of the control group, while CRP level did not show a significant difference between the two groups. Conclusions There was no evidence to suggest that intraoperative vancomycin application is effective in decreasing the risk of postoperative wound infection after instrumented posterior lumbar fusion surgery.

Purpose To determine the prevalence and characteristics of neuropathic pain (NP) in patients with lumbar spinal stenosis (LSS) according to subgroup analysis of symptoms. Materials and Methods We prospectively enrolled subjects with LSS (n=86) who were scheduled to undergo spinal surgery. The patients were divided into two groups according to a chief complaint of radicular pain or neurogenic claudication. We measured patient's pain score using the visual analog scale (VAS), Oswestry Disability Index (ODI) and Leads Assessment of Neuropathic Symptoms and Signs (LANSS). According to LANSS value, the prevalence of NP component pain in patients with LSS was assessed. Statistical analysis was performed to find the relationship between LANSS scores and the other scores. Results From our sample of 86 patients, 31 (36.0%) had a NP component, with 24 (63.4%) in the radicular pain group having NP. However, only seven patients (15.6%) in the neurogenic claudication group had NP. The LANSS pain score was not significantly correlated with VAS scores for back pain, but did correlate with VAS scores for leg pain (R=0.73, p

Study Design Retrospective radiologic study. Objective The sagittal alignment of the cervical spine can be evaluated using either a lateral cervical radiograph or a whole-spine lateral view on which the cervical spine is included. To our knowledge, however, no report has compared the two. The purpose of this work is to identify the difference in radiographic parameters between the cervical spine lateral view and the whole-spine lateral view. Methods We retrospectively analyzed 59 adult patients suffering from neck pain with cervical spine lateral radiographs and whole-spine lateral radiographs from November 2007 to December 2011. The radiographs were measured using standard techniques to obtain the following parameters from the two different radiographs: occipital–C2 angle, C2–C7 angle, C7–sternal angle, sternal slope, T1 slope, C2 central offset distance, the distance between C2 and C7 plumb lines, C4 anteroposterior (AP) diameter, the ratio of C2 central off distance to C4 AP diameter, the ratio of plumb lines’ distance to C4 AP diameter. Results We found that the occipital–C2 angle, sternal slope, and C4 AP diameter were similar, but the C2–C7 angle, C7–sternal angle, T1 slope, C2 central offset distance, distance between C2 and C7 plumb lines, ratio of C2 central off distance to C4 AP diameter, and ratio of plumb lines’ distance to C4 AP diameter were different. However, the error of measurement was greater than the small angular and linear differences between the two views. Conclusions Most numerical values of the measured radiographic parameters appear to be different between the two views. However, the two views are comparable because the numerical differences were smaller than the errors of measurement.

Study Design Computed tomography–based cohort study. Objective Although there are publications concerning the relationship between the vertebral artery and uncinate process, there is no practical guide detailing the dimensions of this region to use during decompression of the intervertebral foramen. The purpose of this study is to determine the anatomic parameters that can be used as a guide for thorough decompression of the intervertebral foramen. Methods Fifty-one patients with three-dimensional computed tomography scans of the cervical spine from 2003 to 2012 were included. On axial views, we measured the distance from the midline to the medial and lateral cortices of the pedicle bilaterally from C3 to C7. On coronal reconstructed views, we measured the minimum height of the uncinate process from the cranial cortex of the pedicle adjacent to the posterior cortex of vertebral body and the maximal height of the uncinate process from the cranial cortex of the pedicle at the midportion of the vertebral body bilaterally from C3 to C7. Results The mean distances from midline to the medial and lateral cortices of the pedicle were 10.1 ± 1.3 mm and 13.9 ± 1.5 mm, respectively. The mean minimum height of the uncinate process from the cranial cortex of the pedicle was 4.6 ± 1.6 mm and the mean maximal height was 6.1 ± 1.7 mm. Conclusions Our results suggest that in most cases, one can thoroughly decompress the intervertebral foramen by removing the uncinate out to 13 mm laterally from the midline and 4 mm above the pedicle without violating the transverse foramen.

The benefits of oblique magnetic resonance imaging (MRI) reformations to assess cervical neural foramina have been reported previously in clinical and cadaveric studies. But there is a paucity of literature investigating intra- and interobserver variabilities for assessing cervical foraminal stenosis using oblique MRI views.To determine the value of oblique MRI views compared with axial and sagittal views for assessing foraminal stenosis of the cervical spine using intra- and interobserver variabilities.A retrospective study.Twenty-six patients were included.Two independent reviewers blindly identified the presence of foraminal stenosis as definite or indeterminate on the sagittal, axial, and oblique views. The assessments using the different views were compared using an independent t test. Intra- and interobserver variabilities were assessed using Kappa analysis.We evaluated the cervical spine MRIs of patients with varying degrees of foraminal stenosis. The mean age of the patients was 60.8 years (range 50-86 years). Male to female ratio was 16:10. The oblique images were obtained by reformatting the scans perpendicular to the long axis of the right and left neural foramina, respectively.The oblique or axial views had significantly greater confidence rates for determining the presence of foraminal stenosis than the sagittal views (92.3%, 88.1% vs. 58.0%, respectively, p=.000). The oblique view had significantly better intraobserver agreement than the sagittal and axial images. Both the axial and oblique views had significantly better interobserver agreement than the sagittal images.Oblique MRI views of the cervical spine significantly reduce the degree of intra- and interobserver variabilities and increase observer confidence in the assessment of foraminal stenosis. Our results suggest that routine use of oblique cervical MRI views might be useful for evaluating cervical foraminal stenosis.

Background:Anterior cruciate ligament (ACL) reconstruction is the current standard of care for ACL tears. However, the results are not consistently successful; autografts or allografts have certain disadvantages; and synthetic grafts have had poor clinical results.Purpose:To determine if recellularization of decellularized tendons combined with mechanical stimulation in a bioreactor could replicate the mechanical properties of the native ACL and be successfully used for ACL reconstruction in vivo.Study Design:Controlled laboratory study.Methods:Porcine tibialis tendons were decellularized and then recellularized with human adult bone marrow–derived stem cells. Tendons were cultured in a tissue bioreactor that provided biaxial cyclic loading for up to 7 days. To reproduce mechanical stresses similar to those experienced by the ACL within the knee joint, the tendons were subjected to simultaneous tension and torsion in the bioreactor. Expression of tendon-specific genes and newly synthesized collagen and glycosaminoglycan were used to quantify the efficacy of recellularization and dynamic bioreactor culture. The ultimate tensile load to failure and stiffness of recellularized constructs were measured after dynamic stimulation. Finally, the tissue-engineered tendons were used to reconstruct the ACL in 24 pigs, and ultimate tensile load to failure and stiffness were assessed after 3 months.Results:Dynamic bioreactor culture significantly increased the expression of tendon-specific genes, the quantity of newly synthesized collagen and glycosaminoglycan, and the ultimate tensile load and stiffness of recellularized tendons. After in vivo reconstruction, the ultimate tensile load and stiffness of the tissue-engineered tendons increased significantly up to 3 months after surgery and were within 80% of the ultimate tensile load of the natural ACL.Conclusion:This translational study indicates that recellularization and dynamic mechanical stimuli can significantly enhance matrix synthesis and ultimate tensile load of decellularized porcine tibialis tendons. This approach to tissue engineering can be very useful for ACL reconstruction and may overcome some of the disadvantages of autografts and allografts.Clinical Relevance:Dynamic bioreactor cultivation of tissue-engineered tendons may overcome the limitations of autografts and allografts.

There has been a wide interest in using platelet-rich plasma (PRP) as a therapeutic agent to enhance spinal fusion. There are two review articles based only on clinical studies regarding the effect of PRP on spinal fusion. However, with regard to both animal model studies and clinical studies, there is no review studies regarding its effect on spinal fusion and no review studies focusing on the platelet count and the concentration of the growth factor in the PRP. The purpose is to review the literatures about the effect of PRP on spinal fusion according to the animal model studies and clinical studies, focusing on the effect of the platelet count and the concentration of the growth factor in the PRP. A PubMed search was performed for English-language articles. We identified 20 articles regarding the effect of PRP on fusion in animal model studies and clinical studies, of which 16 articles met the study criteria of case-control studies or prospective randomized studies for the spinal fusion. The articles were categorized into small-sized animal model, middle-sized animal model, and clinical studies. Studies have shown both beneficial and inhibitory effects. The conclusion that PRP has the stimulating effect on spinal fusion was not reached. However, PRP might promote the human spinal fusion if the platelet count or the concentration of growth factors in the PRP increases.

Study Design Retrospective study. Objective Studies on age-related degenerative changes causing concurrent stenoses in the cervical, thoracic, and lumbar spines (triple stenosis) are rare in the literature. Our objectives were to determine: (1) the incidence of asymptomatic radiologic cervical and thoracic stenosis in elderly patients with symptomatic lumbar stenosis, (2) the incidence of concurrent radiologic spinal stenosis in the cervical and thoracic spines, and (3) the radiologic features of cervical stenosis that might predict concurrent thoracic stenosis. Methods Whole-spine T2 sagittal magnetic resonance images of patients older than 80 and diagnosed with lumbar spinal stenosis between January 2003 and January 2012 were evaluated retrospectively. We included patients with asymptomatic spondylotic cervical and thoracic stenosis. We measured the anteroposterior diameters of the vertebral body, bony spinal canal, and spinal cord, along with the Pavlov ratio and anterior or posterior epidural stenosis at the level of the disk for each cervical and thoracic level. We compared the radiologic parameters between the subgroups of cervical stenosis with and without thoracic stenosis. Results Among the 460 patients with lumbar stenosis, 110 (23.9%) had concurrent radiologic cervical stenosis and 112 (24.3%) had concurrent radiologic thoracic stenosis. Fifty-six patients (12.1%) had combined radiologic cervical and thoracic stenosis in addition to their symptomatic lumbar stenosis (triple stenosis). Anterior epidural stenosis at C7–T1 was associated with a high prevalence of thoracic stenosis. Conclusions It appears that asymptomatic radiologic cervical and thoracic stenosis is common in elderly patients with symptomatic lumbar stenosis.

Study design Prospective study. Objective To evaluate the safety of the lateral mass screw (LMS) fixation. Summary of background data LMS fixation has been known to have risk of injury to vertebral artery, nerve root, or facet joints. Methods A consecutive series of 178 patients undergoing planned LMS fixation were studied. Screw fixation was performed using the freehand technique. Entry point of screws was 2-mm medial from the center of the lateral mass. Planned divergent angle of the screw was 30o. Bicortical fixation was tried in all cases. After the surgery, all patients underwent 3-dimensional computed tomographic scan of the cervical spine. We checked the number of screws in each level, divergent angle of the screws, and violation of foramen transversarium (FT), intervertebral foramen, or facet joint by screws. A reliability test was performed. Results Total 1256 screws were fixed with 269 at C3, 318 at C4, 331 at C5, and 338 screws at C6. Mean divergent angle of the screws were 34.7o/33.1o at C3, 33.9 o/32.1o at C4, 34.7o/32.7o at C5, and 33.6o/30.7o at C6. Incidence of FT violation was 0.876%. FT violation was most common at C6 (6/11 violations). Mean divergent angle in cases of FT violation was 15.0o and was significantly smaller than that of safe cases. There was no injury to vertebral artery. There was no violation of intervertebral foramen. Incidence of facet violation was 1.433%. Seventeen facet violations were within fusion segment. Only 1 screw violated healthy facet. Facet violation was most common at C3 (12/18 violations). Conclusion LMS fixation is a safe stabilizing technique with very low incidence of violation of FT, intervertebral foramen, and facet. There is a possibility of FT violation if the divergent angle was small. FT violation was most common at C6. Facet violation was most common at C3.

Background A prolonged-release formulation of oxycodone/naloxone has been shown to be effective in European populations for the management of chronic moderate to severe pain. However, no clinical data exist for its use in Korean patients. The objective of this study was to assess efficacy and safety of prolonged-release oxycodone/naloxone in Korean patients for management of chronic moderate-to-severe pain. Methods In this multicenter, single-arm, open-label, phase IV study, Korean adults with moderate-to-severe spinal disorder-related pain that was not satisfactorily controlled with weak opioids and nonsteroidal anti-inflammatory drugs received prolonged-release oral oxycodone/naloxone at a starting dose of 10/5 mg/day (maximum 80/40 mg/day) for 8 weeks. Changes in pain intensity and quality of life (QoL) were measured using a numeric rating scale (NRS, 0-10) and the Korean-language EuroQol-five dimensions questionnaire, respectively. Results Among 209 patients assessed for efficacy, the mean NRS pain score was reduced by 25.9% between baseline and week 8 of treatment (p < 0.0001). There was also a significant improvement in QoL from baseline to week 8 (p < 0.0001). The incidence of adverse drug reactions was 27.7%, the most common being nausea, constipation, and dizziness; 77.9% of these adverse drug reactions had resolved or were resolving at the end of the study. Conclusions Prolonged-release oxycodone/naloxone provided significant and clinically relevant reductions in pain intensity and improved QoL in Korean patients with chronic spinal disorders. (ClinicalTrials.gov identifier: NCT01811238).