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Cervical laminoplasty (CLP) is an effective spinal cord decompression method for patients with cervical myelopathy. However, cervical kyphosis after CLP may cause insufficient decompression of the spinal cord. Thus, prevention of cervical kyphosis after CLP and identification of its risk factors are essential.This study aimed to investigate the relationship between preoperative cervical foraminal stenosis and kyphotic changes after CLP.A retrospective study.We reviewed 108 patients who underwent CLP for cervical myelopathy between May 2014 and May 2019 and who were followed up for at least 24 months.For clinical assessments, neck pain, arm pain, neck disability index, Japanese Orthopedic Association scores, EuroQol 5-Dimension, and subjective improvement rate reported by the patients were evaluated. For radiologic parameters, C2-7 Cobb lordotic angle (CLA), C2-7 sagittal vertical axis, T1 slope (TS), TS minus CLA (TS-CLA), and cervical range of motion were assessed preoperatively and postoperatively for 24 months. Cervical foraminal stenosis was evaluated by magnetic resonance imaging and computed tomography.The study population was divided into the kyphosis group (n = 25 patients) and the lordosis group (n = 83 patients) according to the CLA at 24 months postoperatively. Preoperative risk factors related to postoperative kyphosis were analyzed. Statistical analyses were performed using independent two-sample t test, Chi-square test, logistic regression analysis, and linear mixed model.Preoperative foraminal stenosis, CLA, TS, and TS-CLA were significantly different between the kyphosis and lordosis groups. In multivariate logistic regression analysis, foraminal stenosis (odds ratio [OR], 4.471; p = .0242) significantly increased the risk of kyphosis. The probability of developing kyphosis decreased with an increase in the CLA (OR, 0.840; p = .0001), while the probability of developing kyphosis increased with an increase in the TS-CLA (OR, 1.104; p = .0044).Preoperative cervical foraminal stenosis is an independent risk factor for cervical kyphosis following CLP. Thus, CLP may not be a suitable surgical option for cervical myelopathy combined with foraminal stenosis.

The clinical and radiological results before and after surgery were compared and analyzed for patients with multilevel lumbar stenosis who underwent bi-portal endoscopic spine surgery (BESS) and microscopic unilateral laminotomy for bilateral decompression (ULBD). We retrospectively identified 47 and 49 patients who underwent BESS and microscopic ULBD, respectively, who were diagnosed with multi-level lumbar stenosis. Clinical outcomes were evaluated using the visual analog scale score for both back and leg pain, and medication (pregabalin) use and Oswestry Disability Index (ODI) scores for overall treatment outcomes were used pre-operatively and at the final follow-up. Radiological outcomes were evaluated as the percentage of dura expansion volume, and percentage preservation of both facets and both lateral recess angles. The follow-up period of patients was about 17.04 months in the BESS group and about 16.90 months in the microscopic ULBD group. The back and leg visual analog scale (VAS) scores and average pregabalin use decreased more significantly in the BESS group than in the microscopic ULBD group (each p-value 0.0443

As the area and range of surgical treatments in the orthopedic field have expanded, the development of biomaterials used for these treatments has also advanced. Biomaterials have osteobiologic properties, including osteogenicity, osteoconduction, and osteoinduction. Natural polymers, synthetic polymers, ceramics, and allograft-based substitutes can all be classified as biomaterials. Metallic implants are first-generation biomaterials that continue to be used and are constantly evolving. Metallic implants can be made from pure metals, such as cobalt, nickel, iron, or titanium, or from alloys, such as stainless steel, cobalt-based alloys, or titanium-based alloys. This review describes the fundamental characteristics of metals and biomaterials used in the orthopedic field and new developments in nanotechnology and 3D-printing technology. This overview discusses the biomaterials that clinicians commonly use. A complementary relationship between doctors and biomaterial scientists is likely to be necessary in the future.

OBJECTIVE The C2 slope (C2S) is one of the parameters that can determine cervical sagittal alignment, but its clinical significance is relatively unexplored. This study aimed to evaluate the clinical significance of the C2S after multilevel cervical spine fusion. METHODS A total of 111 patients who underwent multilevel cervical spine fusion were included in this study. The C2S, cervical sagittal vertical axis (cSVA), C2–7 lordosis, and T1 slope (T1S) were measured in standing lateral cervical spine radiographs preoperatively and 2 years after the surgery. Clinical outcome measures were visual analog scale (VAS) neck and arm pain scores, Neck Disability Index (NDI), Japanese Orthopaedic Association (JOA) scale score, and patient-reported subjective improvement rate (IR) percentage. Statistical analysis was performed using a paired-samples t-test and Pearson’s correlation, and a receiver operating characteristic (ROC) curve to determine the cutoff values of C2S. RESULTS C2S demonstrated a significant correlation with the cSVA, C2–7 lordosis, T1S, and T1S minus cervical lordosis. C2S revealed a significant correlation with the JOA, neck pain VAS, and NDI scores at 2 years after surgery. Change in the C2S correlated with postoperative neck pain and NDI scores. ROC curves demonstrated the cutoff values of C2S as 18.8°, 22.25°, and 25.35°, according to a cSVA of 40 mm, severe disability expressed by NDI, and severe myelopathy, respectively. CONCLUSIONS C2S can be an additional cervical sagittal alignment parameter that can be a useful prognostic factor after multilevel cervical spine fusion.

Patients with lumbar spinal stenosis may exhibit symptoms such as back pain, radiating pain, and neurogenic claudication. Although long-term outcome of treatments manifests similar results for both nonsurgical and surgical treatments, positive effects such as short-term improvement in symptoms and decreased fall risk may be expected with surgery. Surgical treatment is basically decompression, and a combination of treatments can be added depending on the degree of decompression and the accompanying instability. Recently, minimally invasive surgery has been found to result in excellent outcomes in the treatment of lumbar spinal stenosis. Therefore, better treatment effects can be anticipated with an approach aimed at understanding the overall pathophysiology and treatment methods of lumbar spinal stenosis.

The mortality risk showed a positive correlation as the number of subsequent fractures increased. Hip fracture showed the greatest association with mortality risk, followed by vertebral fracture. For the combination of hip and vertebral fracture, a hip fracture after a vertebral fracture showed the highest mortality risk. It is unclear whether subsequent fractures or a certain location and sequence of subsequent fractures are associated with mortality risk in the elderly. We aimed to investigate the relationship between subsequent fractures and mortality risk. Using the Korean National Health Insurance Research Database, we analyzed the cohort data of 24,756 patients aged > 60 years who sustained fractures between 2002 and 2013. Cox regression was used to assess the mortality risk associated with the number, locations, and sequences of subsequent fractures. Mortality hazard ratios (HRs) for women and men were shown to be associated with the number of subsequent fractures (one, 1.63 (95% confidence interval [CI], 1.48–1.80) and 1.42 (95% CI, 1.28–1.58); two, 1.75 (95% CI, 1.47–2.08) and 2.03 (95% CI, 1.69–2.43); three or more, 2.46(95% CI, 1.92–3.15) and 1.92 (95% CI, 1.34–2.74), respectively). For women, the mortality risk was high when hip (HR, 2.49; 95% CI, 1.80–3.44) or vertebral (HR, 1.40; 95% CI, 1.03–1.90) fracture occurred as a second fracture. Compared with a single hip fracture, there was a high mortality risk in the group with hip fracture after the first vertebral fracture (HR, 2.90; 95% CI, 1.86–4.54), followed by vertebral fracture after the first hip fracture (HR, 1.90; 95% CI, 1.12–3.22). The mortality risk showed a positive correlation as the number of subsequent fractures increased. Hip fracture showed the greatest association with mortality risk, followed by vertebral fracture. For the combination of hip and vertebral fracture, a hip fracture after a vertebral fracture showed the highest mortality risk.

A retrospective observational study.This study investigated the clinical and radiological results of minimally invasive (MI) versus open transforaminal lumbar interbody fusion (TLIF) in patients with single-level lumbar spondylolisthesis over a 10-year period.Few studies have compared 10-year follow-up outcomes between MI-TLIF and open TLIF.We retrospectively collected the outcome data of patients with single-level lumbar spondylolisthesis who underwent TLIF procedures using an MI (n = 108) or open (n = 53) approach. Fifty-two (48%) and 31 (58%) patients in the MI-TLIF and open TLIF groups, respectively, completed the 10-year follow-up. A primary clinical outcome included the Oswestry Disability Index (ODI) as well as visual analog scale (VAS) scores for back and leg pain at baseline and at 2, 5, and 10 years postoperatively. The radiographic fusion rate and incidence of secondary surgery due to adjacent segment disease were assessed at 2, 5, and 10 years postoperatively.Intraoperative blood loss and length of hospitalization were significantly lower in the MI-TLIF group than in the open TLIF group. At 2 years postoperatively, the ODI and VAS scores for back and leg pain were significantly lower in the MI-TLIF group than in the open TLIF group. No significant differences were found in VAS scores for back and leg pain or ODI scores between the two groups at 10 years postoperatively. Radiographic fusion rates and prevalence of secondary surgery for adjacent segment disease were not significantly different between the groups at 10 years postoperatively.Efficacy of MI-TLIF for patients with single-level lumbar spondylolisthesis is comparable to that of open TLIF over 10-years. However, MI-TLIF may have superior perioperative recovery and 2-year postoperative functional outcomes than open TLIF.Level of Evidence: 3.

C5 palsy is a frequent sequela of cervical decompression surgeries for cervical myeloradiculopathy. Although many researchers have suggested various risk factors, such as cord shifting and the correction of lordotic angles, the tethering of the C5 root beneath the narrow foramen is an independent risk factor for C5 palsy. In this study, we tried to investigate different techniques for foramen decompression with posterior cervical fusion and assess the incidence of C5 palsy with each technique depending on the order of foraminal decompression. A combined 540° approach with LMS and uncovertebrectomy was used in group 1. Group 2 combined a 540° approach with pedicle screws and posterior foraminotomy, while posterior approach only with pedicle screws and foraminotomy was used in group 3. For groups 2 and 3, prophylactic posterior foraminotomy was performed before laminectomy. Motor manual testing to assess C5 palsy, the Neck Disability Index (NDI) and the Japanese Orthopedic Association (JOA) scores were determined before and after surgery. Simple radiographs, MRI and CT scans, were obtained to assess radiologic parameters preoperatively and postoperatively. A total of 362 patients were enrolled in this study: 208 in group 1, 72 in group 2, and 82 in group 3. The mean age was 63.2, 65.5, and 66.6 years in groups 1, 2, and 3, respectively. The median for fused levels was 4 for the three groups. There was no significant difference between groups regarding the number of fused levels. Weight, height, comorbidities, and diagnosis were not significantly different between groups. Preoperative JOA scores were similar between groups (p = 0.256), whereas the preoperative NDI score was significantly higher in group 3 than in group 2 (p = 0.040). Mean JOA score at 12-month follow-up was 15.5 ± 1.89, 16.1 ± 1.48, and 16.1 ± 1.48 for groups 1, 2, and 3, respectively; it was higher in group 3 compared with group 1 (p = 0.008) and in group 2 compared with group 1 (p = 0.024). NDI score at 12 months was 13, 12, and 13 in groups 1, 2, and 3, respectively; it was significantly better in group 3 than in group 1 (p = 0.040), but there were no other significant differences between groups. The incidence of C5 palsy was significantly lower in posterior foraminotomy groups with pedicle screws (groups 2 and 3) than in LMS with uncovertebrectomy (group 1) (p < 0.001). Thus, preventive expansive foraminotomy before decompressive laminectomy is able to significantly decrease the root tethering by stenotic lesion, and subsequently, decrease the incidence of C5 palsy associated with posterior only or combined posterior and anterior cervical fusion surgeries. Additionally, such expansive foraminotomy might be appropriate with pedicle screw insertion based on biomechanical considerations.

The influence of the sequence of surgery in the development of prevertebral soft tissue swelling (PSTS) in staged combined multilevel anterior–posterior complex spine surgery was examined. This study was conducted as a retrospective study of patients who underwent staged combined multilevel anterior–posterior complex cervical spine surgery from March 2014 to February 2021. Eighty-two patients were identified, of which fifty-seven were included in the final analysis after screening. PSTS was measured from routine serial monitoring lateral cervical radiographs prior to and after surgery for five consecutive days at each cervical level from C2 to C7 in patients who underwent anterior then posterior (AP) and posterior then anterior–posterior (PAP) surgery. The mean PSTS measurements significantly differed from the preoperative to postoperative monitoring days at all cervical levels (p = 0.0000) using repeated measures analysis of variance in both groups. PSTS was significantly greater in PAP than in AP at level C2 on postoperative day (POD) 1 (p = 0.0001). PSTS was more prominent at levels C2–4 during PODs 2–4 for both groups. In staged combined multilevel anterior–posterior complex spine surgery, PSTS is an inevitable complication. Therefore, surgeons should monitor PSTS after surgery when performing anterior–posterior complex cervical spine surgery, especially in the immediate postoperative period after PAP surgery.

Can we recognize intraoperative real-time stress of orthopedic surgeons and which factors affect the stress of intraoperative orthopedic surgeons with EEG and HRV? From June 2018 to November 2018, 265 consecutive records of intraoperative stress measures for orthopedic surgeons were compared. Intraoperative EEG waves and HRV, comprising beats per minute (BPM) and low frequency (LF)/high frequency (HF) ratio were gathered for stress-associated parameters. Differences in stress parameters according to the experience of surgeons, intraoperative blood loss, and operation time depending on whether or not a tourniquet were investigated. Stress-associated EEG signals including beta 3 waves were significantly higher compared to EEG at rest for novice surgeons as the procedure progressed. Among senior surgeons, the LF/HF ratio reflecting the physical demands of stress was higher than that of novice surgeons at all stages. In surgeries including tourniquets, operation time was positively correlated with stress parameters including beta 1, beta 2, beta 3 waves and BPM. In non-tourniquet orthopedic surgeries, intraoperative blood loss was positively correlated with beta 1, beta 2, and beta 3 waves. Among orthopedic surgeons, those with less experience demonstrated relatively higher levels of stress during surgery. Prolonged operation time or excessive intraoperative blood loss appear to be contributing factors that increase stress.

This study investigated the efficacy of a novel surgical method that relies on the transient fixation of L4 in Lenke Type 5C and 6C adolescent idiopathic scoliosis. Thirty-six transient surgically treated L4 fixation patients were retrospectively evaluated. The first surgery involved mechanical correction of scoliosis; the lowest instrumented vertebra (LIV) was L4. After an average of 1.3 years (range, 0.3–3.4), the second surgery to remove transient L4 pedicle screws was performed. Radiographic parameters and SRS-22 scores were measured. Cobb’s angle, coronal balance, LIV tilting angle, and LIV coronal disc angle clearly improved after the first surgery (p

To investigate the radiologic and clinical outcomes of direct internal fixation for unstable atlas fractures.This retrospective study included 12 patients with unstable atlas fractures surgically treated using C1 lateral mass screws, rods, and transverse connector constructs. Nine lateral mass fractures with transverse atlantal ligament (TAL) avulsion injury and three 4-part fractures with TAL injury (two avulsion injuries, one TAL substance tear) were treated. Radiologic outcomes included the anterior atlantodental interval (AADI) in flexion and extension cervical spine lateral radiographs at 6 months and 1 year after treatment. CT was also performed to visualize bony healing of the atlas at 6 months and 1 year. Visual Analog Scale (VAS) scores for neck pain, Neck Disability Index (NDI) values, and cervical range of motion (flexion, extension, and rotation) were recorded at 6 months after surgery.The mean postoperative extension and flexion AADIs were 3.79±1.56 (mean±SD) and 3.13±1.01 mm, respectively. Then mean AADI was 3.42±1.34 and 3.33±1.24 mm at 6 months and 1 year after surgery, respectively. At 1 year after surgery, 11 patients showed bony healing of the atlas on CT images. Only one patient underwent revision surgery 8 months after primary surgery due to nonunion and instability findings. The mean VAS score for neck pain was 0.92±0.99, and the mean NDI value was 8.08±5.70.C1 motion-preserving direct internal fixation technique results in good reduction and stabilization of unstable atlas fractures. This technique allows for the preservation of craniocervical and atlantoaxial motion.

Background: Anterior cervical discectomy and fusion surgery is a common procedure for degenerative cervical spine. This describes allospacer and implant-related outcomes, comparing medium plate–low screw angle and short plate–high screw angle techniques. Methods: From January 2016 to June 2019, 79 patients who underwent ACDF were prospectively enrolled. Patients were divided, depending on the plate–screw system used: medium plate–low screw angle (12.3 ± 2.5 to 13.2 ± 3.2 degrees), and short plate–high screw angle (22.8 ± 5.3 to 23.3 ± 4.7 degrees). Subsidence, ALOD, and sagittal cervical balance were analyzed using lateral cervical X-rays. NDI and VAS scores were also evaluated. Results: Age for medium plate–low-angled screw group is 58.0 ± 11.3 years, and 55.3 ± 12.0 in the short plate–high-angled screw group (p-value = 0.313). Groups were comparable in mean NDI (p-value = 0.347), VAS (p-value = 0.156), C2–C7 SVA, (p-value = 0.981), and lordosis angle (p-value = 0.836) at 1-year post-surgery. Subsidence was higher in the medium plate–low-angled screw than in the short plate–high-angled screw (25% and 8.5%, respectively, p-value = 0.045). ALOD is also more common in the medium plate group (p-value = 0.045). Conclusion: Use of a short plate and insertion of high-angled screws (more than 20 degrees) has less chance of subsidence and occurrence of ALOD than the traditional technique of using medium plate and low angle.

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.

Study DesignA noninterventional, multicenter, cross-sectional study.PurposeWe investigated the prevalence of neuropathic pain (NP) and patient-reported outcomes (PROs) of the quality of life (QoL) and functional disability in Korean adults with chronic low back pain (CLBP).Overview of LiteratureAmong patients with CLBP, 20%–55% had NP.MethodsPatients older than 20 years with CLBP lasting for longer than three months, with a visual analog scale (VAS) pain score higher than four, and with pain medications being used for at least four weeks before enrollment were recruited from 27 general hospitals between December 2014 and May 2015. Medical chart reviews were performed to collect demographic/clinical features and diagnosis of NP (douleur neuropathique 4, DN4). The QoL (EuroQoL 5-dimension, EQ-5D; EQ-VAS) and functional disability (Quebec Back Pain Disability Scale, QBPDS) were determined through patient surveys. Multiple linear regression analyses were performed to compare PROs between the NP (DN4≥4) and non-NP (DN4ResultsA total of 1,200 patients (females: 65.7%; mean age: 63.4±13.0 years) were enrolled. The mean scores of EQ-5D, EQ-VAS, and QBPDS were 0.5±0.3, 55.7±19.4, and 40.4±21.1, respectively. Among all patients, 492 (41.0%; 95% confidence interval, 38.2%–43.8%) suffered from NP. The prevalence of NP was higher in male patients (46.8%; pppppppConclusionsNP was highly prevalent in Korean patients with CLBP. Patients with CLBP having NP had a lower QoL and more severe dysfunction than those without NP. To enhance the QoL and functional status of patients with CLBP, this study highlights the importance of appropriately diagnosing and treating NP.

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.

Intraoperative bovine-derived topical thrombin is still widely used for hemostasis during surgery. A 38-year-old woman with chronic spontaneous urticaria was referred to the orthopedic surgery department for herniated disk and myelopathy. During the first stage of operation, bovine-derived thrombin powder soaked in Gelfoam was used as a hemostatic aid. After 30 minutes, the patient developed anaphylactic shock with systemic skin rash and angioedema. Repeated intravenous bolus and infusion of vasopressor were carried out, and her blood pressure normalized. Skin test and specific immunoglobulin E test showed positive results for bovine thrombin and beef, respectively. During the second stage of operation (After 10 days from first stage of operation), bovine-derived thrombin powder was excluded and the operation was successful without any unexpected events. Therefore, bovine thrombin should be used with caution because it might cause anaphylaxis.

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.

To report a rare case of odontoid osteomyelitis with atlantoaxial subluxation in a 6-month-old infant.Odontoid osteomyelitis with atlantoaxial subluxation is extremely rare in children. Although several cases have been reported, there have been no studies concerning proper surgical drainage and immobilization in this disease.A 6-month-old infant with odontoid osteomyelitis with atlantoaxial subluxation was surgically treated. The patient underwent a 3-month intravenous and oral antibiotic course and the Minerva body jacket cast was used for 3 months. Follow-up was carried out with computed tomographic scans and a cervical spine dynamogram.At 18 months post-surgery, the patient had completely recovered with no cervical instability. Computed tomographic scans revealed complete fusion of odontoid synchondrosis. The infant remained asymptomatic with a full range of head movement.Surgical drainage and proper immobilization appears to be a satisfactory treatment for pyogenic osteomyelitis of odontoid synchondrosis secondary to retropharyngeal abscess and atlantoaxial subluxation.N/A.

Objective: We investigated causes and results of revision surgeries after artificial disc replacement of cervical spine (C-ADR). Methods: Twenty-one patients (mean age: 52.8) who underwent revision surgery after C-ADR and who had a minimum 2-year of follow-up were included into this study. The mean time between the primary and revision surgeries was 21 months. During their primary surgeries, 14 patients underwent single level C-ADR, 2 two-level C-ADR, and 5 two-level hybrid surgery for 16 radiculopathy, 3 myelopathy, and 2 adjacent segment diseases. Causes for revision surgeries were at least one of the followings: 17 poor patient selections, 7 insufficient decompressions, 7 malpositions, 6 subsidences, 3 osteolysis, and 1 postoperative infection. Results: Sixteen patients underwent anterior removal of C-ADR, one-level discectomy and fusion (N = 11), two-level discectomy (N = 3) or one-level corpectomy (N = 2) and fusion. Three patients of keel type C-ADR with heterotopic ossification underwent posterior laminoforaminotomy and fusion. Two patients underwent combined procedures due to infection or severe subsidence and osteolysis. At the 2-year follow-up, neck (7.3 vs 1.6) and arm (7.0 vs 1.3) visual analog scales and Neck Disability Index score (46.7 vs 16.32) were improved (all, p

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.

Study Design Survey based study. Purpose To assess the degree of agreement in level selection of laminoplasty (LP) for the selected cervical myeloradiculopathy cases between experienced spine surgeons. Overview of Literature Although, cervical LP is a widely used surgical technique for multi-level spinal cord compression, until now there is no consensus about how many segments or which segments should be opened to achieve a satisfactory decompression. Methods Thorough clinical and radiographic data (plain X-ray, computed tomography, and magnetic resonance imaging) of 30 patients who had cervical myelopathy were prepared. The data were provided to three independent spine surgeons with over 10 years experience in operation of their own practices. They were questioned about the most preferable surgical method and suitable decompression levels. The second survey was carried out after 6 months with the same cases. If the level difference between respondents was a half level or below, agreement was considered acceptable. The intraobserver and interobserver agreements in level selection were assessed by kappa statistics. Results Three respondents selected LP as an option for 6, 8, and 22 cases in the first survey and 10, 21, and 24 cases in the second survey. The reasons for selection of LP were levels of ossification of the posterior longitudinal ligament (p=0.004), segmental kyphotic deformity (p=0.036) and mean compression score (p=0.041). Intraobserver agreement showed variable results. Interobserver agreement was poor to fair by perfect matching (kappa=0.111–0.304) and fair to moderate by acceptable matching (kappa=0.308–0.625). Conclusions The degree of agreement for level selection of LP was not high even though experienced surgeons would choose the opening segments on the basis of same criteria. These results suggest that more specific guidelines in determination of levels for LP should be required to decrease unnecessary wide decompression according to individual variance.

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.

STUDY DESIGN A prospective study. OBJECTIVE The aim of this study was to provide methods for predicting ideal trajectory and position of C1 lateral mass screw (C1LMS) from plain radiographs. SUMMARY OF BACKGROUND DATA There has been no study on prediction of C1LMS position using plain radiographs. METHODS A total of 40 consecutive subjects (with 79 screws) who had undergone C1LMS placement were enrolled. To evaluate the C1LMS position, the positions of screw head and tips on anteroposterior radiographs, screw length, and height on lateral radiograph were graded as 0, I, and II, respectively. On the postoperative computed tomography images, we analyzed lateral mass (LM) perforation, screw-thread engagement percent (%), bicortical fixation, extruded screw length, and violation of adjacent joints. RESULTS Screws with tip located medial to LM (tip 0) showed LM perforation in all cases. Polyaxial head located within the LM (head 0) or crossing the lateral margin of the LM (head I) showed no LM perforation. Screw-thread engagement percent was the highest with head I-tip I (medial half of LM) position (97.6%), followed by head 0-tip I (90.5%) and head I-tip II (lateral half of LM) (86.4%). Screws longer than the posterior half of C1 anterior arch (AA) showed bicortical fixation in all cases with mean extruded screw length of 1.9 mm. Adjacent joint was not violated in 98%, with the screw height below half of C1AA. CONCLUSIONS On an anteroposterior radiograph, a C1LMS with the screw head located on the lateral margin of the LM and with the screw tip in the medial half of the LM resulted in the safest and longest trajectory. On lateral radiograph, a screw tip that is placed within the anterior-inferior quadrant of the C1AA results in safe bicortical fixation without injury to the adjacent structures. These plain radiographic findings may be helpful both postoperatively and intraoperatively for assessing the trajectory and length of the screw.

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.

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.

Study design This was a prospective cohort study. Objectives To find out any differences in clinical outcomes when adding an en bloc total uncinate process resection (TUPR) to conventional anterior cervical discectomy and fusion (ACDF) to relieve an impinged nerve root. Summary of background data There has been a long debate on the extent of cervical decompression needed when ACDF is done for patients with foraminal stenosis. Materials and methods We included 606 patients who underwent ACDF due to foraminal stenosis. Minimum follow-up was 2 years. Patients with a soft disk herniation, myelopathy, anterior-posterior combined surgery or revision surgery were excluded. There were 275 patients (group U) who underwent ACDF with TUPR and 331 patients (group N) who underwent ACDF without TUPR. Clinical outcome measures were neck pain and arm pain, both assessed using Visual Analog Scale (VAS). We also measured Neck Disability Index (NDI) and patient-reported subjective improvement rate (PRSIR) in percentage. These parameters were measured preoperatively, immediately postoperatively, at 6 weeks as well as 3, 6, 9, 12 and 24 months. Statistical analysis was performed using independent sample t test and paired sample t test. Results Preoperative neck and arm pain, and NDI were similar between the 2 groups. All 4 parameters in both groups improved significantly at 6 weeks follow-up and the improved outcomes were maintained up to the 24 month follow-up. There were no significant differences between the 2 groups in overall neck pain VAS, NDI, and PRSIR. There was a significant difference in arm pain VAS statistically all throughout the follow-up period, with group U having lesser arm pain. Conclusions Overall clinical outcomes were significantly improved after the ACDF whether an en bloc uncinate process resection was added or not. However, arm pain VAS was significantly less statistically in the uncinate resection group at all times.

Background Context The efficacy and safety of recombinant human bone morphogenetic protein-2 (rhBMP-2) as a bone graft substitute in spinal fusion has been widely researched. However, no study of the efficacy and safety of Escherichia coli-derived rhBMP-2 (E.BMP-2) with a hydroxyapatite (HA) carrier has been proposed. Purpose This study aimed to compare the efficacy and safety of fusion materials between E.BMP-2 and autogenous iliac bone graft in posterolateral fusion (PLF). Study Design/Setting An open, active-controlled, randomized, multicenter trial was carried out. Patient Sample This study included 93 patients who underwent single-level lumbar or lumbosacral PLF. Outcome Measures The primary outcome measure was computed tomography (CT)-based fusion rate at 12 and 24 weeks. Secondary outcome measures were fusion grade by radiographs and CT at 12 and 24 weeks and changes in Oswestry Disability Index (ODI), Short Form-36 (SF-36) Health Survey, and visual analogue scale (VAS). Methods Patients who underwent 1-level PLF (between L1 and S1) for severe spinal stenosis or grade 1 spondylolisthesis were randomized to receive E.BMP-2 with an HA carrier (E.BMP-2 group) or autogenous iliac bone graft (AIBG group). Thin-section CT ( Results A total of 100 patients were enrolled in this trial. Among them, 93 patients underwent planned surgery. Preoperative demographic and clinical data showed no difference between groups. CT-based fusion rates were 100.0% (41/41) for the E.BMP-2 group and 90.2% (46/51) for the AIBG group (p=.062) at 12 weeks and 100.0% (41/41) and 94.1% (48/51) (p=.251) at 24 weeks, respectively. Fusion grade based on radiographs and CT showed non-inferiority of the E.BMP-2 group compared with the AIBG group. All clinical parameters improved postoperatively. However, there was no difference in changes in VAS, ODI, or SF-36 between the groups. No serious adverse event related to E.BMP-2 was found. Conclusions The fusion rate of E.BMP-2 was comparable with that of AIBG following PLF. Good clinical efficacy and safety of E.BMP-2 in spinal fusion were also revealed. It was also suggested that HA shows suitability as a carrier for E.BMP-2. Thus, E.BMP-2 with an HA carrier can be an alternative bone graft material in spinal fusion.

In vitro experiment using degenerated human ligamentum flavum (LF) and herniated intervertebral disk (IVD).To investigate the role and effect of degenerated and herniated IVDs on LF hypertrophy and ossification.Spinal stenosis is caused, in part, by hypertrophy and ossification of the LF, which are induced by aging and degenerative process. It is well known that degenerated IVDs spontaneously produce inflammatory cytokines. Therefore, we hypothesized that degenerated IVD may affect adjacent LF through secreted inflammatory cytokines.LF and herniated lumbar IVD tissues were obtained during surgical spinal procedures. LF fibroblasts were isolated by enzymatic digestion of LF tissue. LF cell cultures were treated with disk supernatant from herniated IVDs. Secreted cytokines from IVD tissue culture were detected by enzyme-linked immunosorbent assay. After analysis of cytotoxicity, DNA synthesis was measured. Reverse transcription-polymerase chain reaction for mRNA expressions of types I, II, III, V, and XI collagen and osteocalcin, and histochemical stains were performed.Supernatant from tissue culture of herniated IVD showed increased production of interleukin-1α, interleukin-6, tumor necrosis factor-α, prostaglandin E2, and nitric oxide compared with disk tissue culture from traumatic condition. There was no cytotoxicity in LF cells treated with disk supernatant from herniated IVDs. There was significant increase in DNA synthesis, upregulation in mRNA expression of types III, XI collagen and osteocalcin, whereas variable expression pattern of type I and V, and strong positive stains for Von Kossa and alkaline phosphatase in LF cultures with disk supernatant.Degenerated and herniated IVDs provide an important pathomechanism in hypertrophy and ossification of the LF through inflammatory cytokines.

Summary Objective To evaluate the clinical characteristics and outcomes of patients with hematogenous vertebral osteomyelitis (HVO) caused by gram-negative bacteria (GNB). Methods We conducted a retrospective chart review of adult patients with HVO from three tertiary-care hospitals over a 7-year period. Results Of the 313 microbiologically diagnosed HVO cases, GNB was responsible for 65 (20.8%) cases. Compared with patients with MSSA HVO, patients with GNB HVO were more likely to be female ( P = 0.03) and have diabetes ( P = 0.03), but less likely to have epidural abscess ( P = 0.02) and paravertebral abscess ( P = 0.003). Clinical outcomes were similar between the GNB and MSSA groups, including in-hospital mortality (4.6% vs. 7.8%; P = 0.53), recurrence (9.7% vs. 4.3%; P = 0.20), and sequelae (31.7% vs. 32.2%; P = 0.95). Among GNB-infected patients, recurrence rates differed according to the total duration of antibiotic treatment: 40.0% (4–6 weeks), 33.3% (6–8 weeks), and 2.1% (≥8 weeks) ( P = 0.002). Conclusions GNB HVO was responsible for 20.8% of adult cases of HVO. Despite some differences in clinical and radiological presentation, clinical outcomes were similar between GNB and MSSA HVO. Antibiotic therapy for ≥8 weeks may benefit patients with GNB HVO.

Background: While most studies of Duchenne muscular dystrophy scoliosis focus on technical and radiographic indices, functional status is a more important factor to consider in the management of Duchenne muscular dystrophy. The objectives of the current study were to compare the pulmonary function, radiographic outcome, and functional recovery, with use of validated questionnaires, in surgically and nonsurgically treated patients with Duchenne muscular dystrophy who have scoliosis. Methods: Sixty-six patients (forty treated surgically and twenty-six treated nonsurgically) with a minimum follow-up of two years were included in this study. Forced vital capacity, radiographic parameters (the Cobb angle, lordosis, and pelvic obliquity), and functional status, according to the modified Rancho scale and manual muscle test, were measured preoperatively and at the time of the final follow-up. The Muscular Dystrophy Spine Questionnaire (MDSQ) was completed at the final follow-up evaluation. Results: Pulmonary function, functional scores (manual muscle test and modified Rancho scale), and radiographic measurements, except for lordosis, were similar for both groups at the time of the initial consultation (p > 0.05). At the time of the final follow-up, all radiographic parameters were significantly improved in the surgical group compared with the nonsurgical group. The mean score (and standard deviation) on the manual muscle test was not significantly different between the surgical and nonsurgical groups (23.2 ± 8.3 versus 22.8 ± 6.3; p = 0.828). The mean score on the modified Rancho scale also showed similar results in the groups (3.9 ± 0.3 and 4.04 ± 0.3, respectively; p = 0.088). The surgical group had higher mean MDSQ scores than the nonsurgical group (35.1 ± 14.7 and 26.9 ± 9.9, respectively; p = 0.008). Both groups showed a decrease in forced vital capacity at the time of the final follow-up, but the deterioration of forced vital capacity was significantly slower (p = 0.035) in the surgical group (268 ± 361 mL) than in the nonsurgical group (536 ± 323 mL). Conclusions: Surgery in patients who had Duchenne muscular dystrophy with scoliosis improved function and decreased the rate of deterioration of forced vital capacity compared with patients treated conservatively. However, the muscle power and forced vital capacity decreased in both groups. Level of Evidence: Therapeutic Level II. See Instructions for Authors for a complete description of levels of evidence.

Dupuytren's disease is a fibroproliferative connective tissue disorder characterized by contracture of the palmer fascia of the hand. Relaxin (RLN) is a multifunctional factor which contributes to the remodeling of the pelvic ligament by inhibiting fibrosis and inflammatory activities. The aim of this study was to investigate the effect of the RLN gene on the inhibition of fibrosis in myofibroblastic cells. Myofibroblast cells with adenovirus LacZ (Ad-LacZ) as a marker gene or adenovirus relaxin (Ad-RLN) as therapeutic gene showed transgene expressions in beta-galactosidase assay and Western blot analysis. Myofibroblastic cells with Ad-RLN demonstrated a 22% and 48% reduction in collagen I and III mRNA expressions respectively, a 50% decrease in MMP-1, 70% decrease in MMP-2, 80% decrease in MMP-9, and a 15% reduction in MMP-13 protein expression compared with cultures with viral control and saline control. In addition, myofibroblastic cells with Ad-RLN showed a 40% decrease in TIMP 1 and a 15% increase in TIMP 3 protein expression at 48 h compared to cultures with viral control and saline control. Also, myofibroblastic cell with Ad-RLN demonstrated a 74% inhibition of fibronectin and a 52% decrease in total collagen synthesis at 48 h compared with cultures with viral control and saline control. In conclusion, the RLN gene render antifibrogenic effect on myofibroblastic cells from Dupuytren's nodule via direct inhibition of collagen synthesis not through collagenolytic pathway such as MMP-1, -13, TIMP 1, and 3. Therefore relaxin can be an alternative therapeutic strategy in initial stage of Dupuytren's disease by its antifibrogenic effect. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 32:515–523, 2014.