Search

Study Design: A retrospective cohort study using prospectively collected data., Objective: This study primarily aimed to investigate the risk factors for surgery-related complications in primary thoracic spine surgery for degenerative diseases using a surgeon-maintained database. The secondary purpose was to elucidate the characteristics of surgically treated thoracic myelopathy that also required cervical and/or lumbar spine surgery in the study period., Summary of Background Data: Few studies reported surgical complications and the feature of tandem spinal stenosis in thoracic myelopathy in detail because of their rarity., Materials and Methods: This study included 840 thoracic myelopathy patients undergoing primary surgery for degenerative diseases from 2012 to 2021, investigating the effects of diseases, surgical procedures, and patient demographics on postoperative neurological deterioration, dural tear, dural leakage, surgical-site infection, and postoperative hematoma. In thoracic myelopathy patients who were surgically treated and also undergoing cervical and/or lumbar surgery, we investigated the proportion, the effects of diseases, and the order and intervals between surgeries., Results: Multivariate logistic regression revealed that significant risk factors ( P <0.05) for postoperative neurological deterioration were intervertebral disk herniation [odds ratio (OR): 4.59, 95% confidence interval (CI): 1.32-16.0) and degenerative spondylolisthesis (OR: 11.1, 95% CI: 2.15-57.5). Ossification of the ligamentum flavum (OR: 4.12, 95% CI: 1.92-8.86), anterior spinal fusion (OR: 41.2, 95% CI: 4.70-361), and circumferential decompression via a posterior approach (OR: 30.5, 95% CI: 2.27-410) were risk factors for dural tear. In thoracic myelopathy patients surgically treated, 37.0% also underwent degenerative cervical and/or lumbar surgery., Conclusions: Pathologies involving anterior decompression and instability increased the risk of postoperative neurological deterioration. The risk of dural tear was increased when dura mater adhesions were likely to be directly operated upon. It should be recognized that a relatively high proportion (37.0%) of surgically treated thoracic myelopathy patients also underwent cervical and/or lumbar surgery., Competing Interests: The authors declare no conflict of interest., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

This prospective multicenter study, established by the Japanese Ministry of Health, Labour and Welfare and involving 27 institutions, aimed to compare postoperative outcomes between laminoplasty (LM) and posterior fusion (PF) for cervical ossification of the posterior longitudinal ligament (OPLL), in order to address the controversy surrounding the role of instrumented fusion in cases of posterior surgical decompression for OPLL. 478 patients were considered for participation in the study; from among them, 189 (137 and 52 patients with LM and PF, respectively) were included and evaluated using the Japanese Orthopaedic Association (JOA) scores, the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), and radiographical measurements. Basic demographic and radiographical data were reviewed, and the propensity to choose a surgical procedure was calculated. Preoperatively, there were no significant differences among the participants in terms of patient backgrounds, radiographical measurements (K-line or cervical alignment on X-ray, OPLL occupation ratio on computed tomography, increased signal intensity change on magnetic resonance imaging), or clinical status (JOA score and JOACMEQ) after adjustments. The overall risk of perioperative complications was found to be lower with LM (odds ratio [OR] 0.40, p = 0.006), and the rate of C5 palsy occurrence was significantly lower with LM (OR 0.11, p = 0.0002) than with PF. The range of motion (20.91° ± 1.05° and 9.38° ± 1.24°, p < 0.0001) in patients who had PF was significantly smaller than in those who had LM. However, multivariable logistic regression analysis showed no significant difference among the participants in JOA score, JOA recovery rate, or JOACMEQ improvement at two years. In contrast, OPLL progression was greater in the LM group than in the PF group (OR 2.73, p = 0.0002). Both LM and PF for cervical myelopathy due to OPLL had resulted in comparable postoperative outcomes at 2 years after surgery., (© 2022. The Author(s).)

Importance: The optimal management for acute traumatic cervical spinal cord injury (SCI) is unknown., Objective: To determine whether early surgical decompression results in better motor recovery than delayed surgical treatment in patients with acute traumatic incomplete cervical SCI associated with preexisting canal stenosis but without bone injury., Design, Setting, and Participants: This multicenter randomized clinical trial was conducted in 43 tertiary referral centers in Japan from December 2011 through November 2019. Patients aged 20 to 79 years with motor-incomplete cervical SCI with preexisting canal stenosis (American Spinal Injury Association [ASIA] Impairment Scale C; without fracture or dislocation) were included. Data were analyzed from September to November 2020., Interventions: Patients were randomized to undergo surgical treatment within 24 hours after admission or delayed surgical treatment after at least 2 weeks of conservative treatment., Main Outcomes and Measures: The primary end points were improvement in the mean ASIA motor score, total score of the spinal cord independence measure, and the proportion of patients able to walk independently at 1 year after injury., Results: Among 72 randomized patients, 70 patients (mean [SD] age, 65.1 [9.4] years; age range, 41-79 years; 5 [7%] women and 65 [93%] men) were included in the full analysis population (37 patients assigned to early surgical treatment and 33 patients assigned to delayed surgical treatment). Of these, 56 patients (80%) had data available for at least 1 primary outcome at 1 year. There was no significant difference among primary end points for the early surgical treatment group compared with the delayed surgical treatment group (mean [SD] change in ASIA motor score, 53.7 [14.7] vs 48.5 [19.1]; difference, 5.2; 95% CI, -4.2 to 14.5; P = .27; mean [SD] SCIM total score, 77.9 [22.7] vs 71.3 [27.3]; P = .34; able to walk independently, 21 of 30 patients [70.0%] vs 16 of 26 patients [61.5%]; P = .51). A mixed-design analysis of variance revealed a significant difference in the mean change in ASIA motor scores between the groups (F1,49 = 4.80; P = .03). The early surgical treatment group, compared with the delayed surgical treatment group, had greater motor scores than the delayed surgical treatment group at 2 weeks (mean [SD] score, 34.2 [18.8] vs 18.9 [20.9]), 3 months (mean [SD] score, 49.1 [15.1] vs 37.2 [20.9]), and 6 months (mean [SD] score, 51.5 [13.9] vs 41.3 [23.4]) after injury. Adverse events were common in both groups (eg, worsening of paralysis, 6 patients vs 6 patients; death, 3 patients vs 3 patients)., Conclusions and Relevance: These findings suggest that among patients with cervical SCI, early surgical treatment produced similar motor regain at 1 year after injury as delayed surgical treatment but showed accelerated recovery within the first 6 months. These exploratory results suggest that early surgical treatment leads to faster neurological recovery, which requires further validation., Trial Registration: ClinicalTrials.gov Identifier: NCT01485458; umin.ac.jp/ctr Identifier: UMIN000006780.

Ossification of the posterior longitudinal ligament (OPLL) is a progressive disease. The bridging of ossified lesions to the vertebral body gradually increases, thereby decreasing the mobility of the cervical spine; thus, cervical spine function may decrease over time. However, cervical spine function in patients with cervical OPLL has not been evaluated in large prospective studies. Therefore, we conducted a prospective multicenter study to clarify whether ossification spread can influence cervical spine function and quality of life (QOL) in patients with cervical OPLL. In total, 238 patients (162 men, 76 women; mean age, 63.9 years) were enrolled from 16 institutions. Each patient underwent whole spine computed tomography and was evaluated for cervical spine function and QOL using the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ). In the multivariate regression analysis, a higher neck VAS score and a larger number of bridge formations of OPLL in the whole spine were significant predictors of adverse outcomes related to cervical spine function. This is the first prospective multicenter study to reveal the impact of ossification spread on cervical spine function. These findings are important to understand the natural course of OPLL and can serve as controls when evaluating postoperative cervical spine function., (© 2021. The Author(s).)

Although favourable surgical outcomes for myelopathy caused by cervical ossification of the posterior longitudinal ligament (OPLL) have been reported, factors significantly associated with post-operative neck pain attenuation still remain unclear. The primary aim of the present study was to determine factors significantly associated with post-operative neck pain attenuation in patients with cervical OPLL using a prospective multi-centre registry of surgically treated cervical OPLL. Significant postoperative neck pain reduction (50% reduction of neck pain) was achieved in 31.3% of patients. There was no significant difference in neck pain attenuation between surgical procedures. Statistical analyses with univariate analyses followed by stepwise logistic regression revealed neurological recovery as a factor having a significant positive association with post-operative neck pain attenuation (p = 0.04, odds ratio 5.68 (95% confidence interval: 1.27-22.2)). In conclusion, neurological recovery was an independent factor having a significant positive association with post-operative neck pain attenuation in patients with cervical myelopathy caused by OPLL who underwent cervical spine surgery.

Objective: Although concomitant foraminotomy has been reported to increase the risk of postoperative upper limb palsy (ULP) in cervical laminoplasty, the specific effects of concomitant foraminotomy on ULP remain uncertain. This study aimed to clarify the effect of concomitant foraminotomy on ULP in cervical laminoplasty., Methods: We identified 19 patients who developed ULP after laminoplasty with concomitant foraminotomy for radiculomyelopathy with nerve root impingement (laminoplasty with concomitant foraminotomy group [F-group]) from 4080 patients who underwent primary cervical laminoplasty at 27 affiliated institutions between 2012 and 2018. An age- and sex-matched control group comprised patients who developed ULP after laminoplasty without concomitant foraminotomy (n = 76, 4:1 ratio with F-group). Collected data included the time of onset and distribution of ULP (side and level). The site of foraminotomy was recorded in the F-group., Results: The F-group showed a significantly higher incidence of ULP than the candidates for the control group (15.1% vs. 3.1%, P < 0.001). The site of foraminotomy was consistent with the distribution of ULP in 79% (15 of 19 patients) of the F-group. The F-group showed a significantly higher proportion of preoperative upper-limb muscle weakness (74% vs. 37%, P = 0.005) and early-onset ULP occurring by postoperative day 1 (63% vs. 33%, P = 0.02) compared with the control group., Conclusions: Our results indicate that the foraminotomy procedure in the stenotic foramen is directly involved in ULP. Combined with a previous report suggesting that early-onset ULP is associated with thermal nerve damage, our results indicate that thermal nerve damage partly explains the increased incidence of ULP in the F-group., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Aims: This study, using a surgeon-maintained database, aimed to explore the risk factors for surgery-related complications in patients undergoing primary cervical spine surgery for degenerative diseases., Methods: We studied 5,015 patients with degenerative cervical diseases who underwent primary cervical spine surgery from 2012 to 2018. We investigated the effects of diseases, surgical procedures, and patient demographics on surgery-related complications. As subcategories, the presence of cervical kyphosis ≥ 10°, the presence of ossification of the posterior longitudinal ligament (OPLL) with a canal-occupying ratio ≥ 50%, and foraminotomy were selected. The surgery-related complications examined were postoperative upper limb palsy (ULP) with a manual muscle test (MMT) grade of 0 to 2 or a reduction of two grade or more in the MMT, neurological deficit except ULP, dural tear, dural leakage, surgical-site infection (SSI), and postoperative haematoma. Multivariate logistic regression analysis was performed., Results: The significant risk factors (p < 0.050) for ULP were OPLL (odds ratio (OR) 1.88, 95% confidence interval (CI) 1.29 to 2.75), foraminotomy (OR 5.38, 95% CI 3.28 to 8.82), old age (per ten years, OR 1.18, 95% CI 1.03 to 1.36), anterior spinal fusion (OR 2.85, 95% CI 1.53 to 5.34), and the number of operated levels (OR 1.25, 95% CI 1.11 to 1.40). OPLL was also a risk factor for neurological deficit except ULP (OR 5.84, 95% CI 2.80 to 12.8), dural tear (OR 1.94, 95% CI 1.11 to 3.39), and dural leakage (OR 3.15, 95% CI 1.48 to 6.68). Among OPLL patients, dural tear and dural leakage were frequently observed in those with a canal-occupying ratio ≥ 50%. Cervical rheumatoid arthritis (RA) was a risk factor for SSI (OR 10.1, 95% CI 2.66 to 38.4)., Conclusion: The high risk of ULP, neurological deficit except ULP, dural tear, and dural leak should be acknowledged by clinicians and OPLL patients, especially in those patients with a canal-occupying ratio ≥ 50%. Foraminotomy and RA were dominant risk factors for ULP and SSI, respectively. An awareness of these risks may help surgeons to avoid surgery-related complications in these conditions. Cite this article: Bone Joint J 2021;103-B(1):157-163.

Background: The optimal surgical procedure for the treatment of cervical ossification of the posterior longitudinal ligament (OPLL) remains controversial because there are few comprehensive studies investigating the surgical methods. Therefore, we conducted a systematic review and meta-analysis to evaluate evidence in the literature and compare the surgical outcomes of anterior decompression with fusion (ADF) and laminoplasty (LAMP), which are representative procedures for cervical OPLL., Methods: An extensive literature search was performed using PubMed, Embase, and the Cochrane Library to identify comparative studies of ADF and LAMP for cervical OPLL. The language was restricted to English, and the year of publication was from January 1980 to December 2018. We extracted outcomes from the studies, such as preoperative and postoperative Japanese Orthopaedic Association (JOA) score, cervical alignment, surgical complications and reoperation rate. Then, meta-analysis was performed for these surgical outcomes., Results: Twelve studies were obtained, including 1 prospective cohort study and 11 retrospective cohort studies. In the meta-analysis, neurological recovery rate in JOA score was greater in ADF than in LAMP, especially in patients with a large canal occupying ratio (≥60%) and preoperative kyphotic alignment. ADF also exhibited more favorable results in postoperative cervical alignment. In contrast, operating time and intraoperative blood loss were greater in ADF. Surgical complications were more frequently seen in ADF, leading to higher rates of reoperation., Conclusions: This systematic review and meta-analysis showed both the merits and shortcomings of ADF and LAMP. ADF resulted in more favorable neurological recovery compared to LAMP, especially for patients with massive OPLL and kyphotic alignment. Postoperative cervical lordosis was also better preserved in ADF. However, ADF was associated with greater surgical invasion and higher incidences of surgical complications., (Copyright © 2019 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Background: Biologic agents (BAs) enabled not only a reduction of disease activity but also a slowing down of structural damage to the joints in patients with rheumatoid arthritis (RA). However, the incidence of cervical lesions in patients with RA is still high., Purpose: To elucidate the predictors for the progression of two different cervical lesions in patients with RA under BA treatment., Methods: Of 151 subjects who received more than two years of continuous BA treatment, 101 subjects who had cervical X-ray images taken at baseline and final visit were enrolled. The mean disease duration and mean radiography interval were 10.6 years and 4.4 years, respectively. The existence and progression of cervical lesions (atlanto-axial subluxation [AAS], vertical subluxation [VS], and subaxial subluxation [SS]) were investigated. And predictors for the AAS or VS progression were analyzed by multivariate logistic regression analysis., Results: The incidence of cervical lesions at baseline were no pre-existing cervical lesion (none) in 50 cases (50%), AAS only in 32 (32%), both AAS and VS in 12 (12%), and VS only in 7 cases (7%). In the none group, only 4 cases of AAS progression (8%) was observed during the follow-up. In contrast, in the groups with pre-existing cervical lesions, a high incidence of VS progression was observed (63% in the AAS only group, 58% in the AAS + VS group, and 71% in the VS only group). Multivariate regression analysis demonstrated that the DAS-CRP value at baseline (odds ratio [OR] = 9.23) and matrix metaloprotease-3 level at baseline (OR = 1.01) were significant predictors for the progression of AAS, and pre-existing AAS (OR = 18.38) was a sole significant predictor for the progression of VS., Conclusions: Cervical lesions progressed irrespective of disease activity after AAS development. Strict disease control before the development of AAS is crucial for preventing further progression and development of cervical lesions., (Copyright © 2018 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.)

Study Design: This is prospective observational study., Objective: To prospectively investigate the correlation among axial neck pain; a newly developed patient-based quality of life outcome measure, the Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire (JOACMEQ); and cervical sagittal alignment after open-door laminoplasty for cervical myelopathy., Summary of Background Data: Many studies have focused on postoperative axial neck pain after laminoplasty. However, the correlation among cervical sagittal alignment, neck pain, and JOACMEQ has not been investigated., Materials and Methods: In total, 57 consecutive patients treated by open-door laminoplasty for cervical myelopathy were included (mean age, 63.7 y; 15 women and 42 men) and divided into 2 groups according to diagnosis [cervical spondylotic myelopathy (CSM) group: 35 patients, and ossification of the posterior longitudinal ligament (OPLL) group: 22 patients]. JOA score, a subdomain of cervical spine function (CSF) in the JOACMEQ, and the visual analog scale for axial neck pain were assessed preoperatively and 12 months postoperatively. Radiographic cervical sagittal parameters were measured by C2 sagittal vertical axis (C2 SVA), C2-C7 lordosis, C7 sagittal slope (C7 slope), and range of motion., Results: C2 SVA values in both groups shifted slightly anteriorly between preoperative and 12-month postoperative measurements (CSM: +19.7±10.9 mm; OPLL: +22.1±13.4 mm vs. CSM: +23.2±16.1 mm; OPLL: +28.7±15.4 mm, respectively). Postoperative axial neck pain in the OPLL group showed strong negative correlations with C2 SVA and C7 slope. Strong negative correlations were found between axial neck pain and CSF in both the preoperative CSM and OPLL groups (CSM: r=-0.45, P=0.01; OPLL: r=-0.61, P<0.01) and between axial neck pain and CSF in the postoperative OPLL group (r=-0.51, P=0.05)., Conclusions: This study demonstrated a significant negative correlation between neck pain and CSF in both the CSM and OPLL groups preoperatively and in the OPLL group postoperatively. Radiographic cervical sagittal alignment did not significantly correlate with preoperative or postoperative axial neck pain.

Aims: In this prospective observational study, we investigated the time-dependent changes and correlations of upper arm performance tests (ten-second test and Simple Test for Evaluating Hand Function (STEF), the Japanese Orthopaedic Association (JOA) score, and the JOA Cervical Myelopathy Evaluation Questionnaire (JOACMEQ) in 31 patients with cervical myelopathy who had undergone surgery., Patients and Methods: We hypothesised that all the indices correlate with each other, but show slightly different recovery patterns, and that the newly described JOACMEQ is a sensitive outcome measure., Results: Peak recoveries were achieved one month post-operatively in the ten-second test and JOACMEQ upper extremity function (UEF) subscale, and at three months in the JOA and STEF scores. The recoveries of all indices were maintained until six months post-operatively. The upper extremity function (UEF) subscale in the JOACMEQ showed the strongest correlation with STEF although all the indices correlated with each other. Patients with ≥ 20 and < 20 acquired points in the UEF subscale were classified into the UEF-improved and UEF-unimproved groups. Comparisons between the groups showed that pre-operative evaluation of "coordinated motion" of the STEF was significantly low in the UEF-unimproved group., Conclusion: These results indicate that the JOACMEQ is a concise, sensitive, patient-based outcome measure for evaluating functional recovery in patients with cervical myelopathy who have undergone surgery. Cite this article: Bone Joint J 2016;98-B:990-6., (©2016 The British Editorial Society of Bone & Joint Surgery.)

Object: The upper cervical spine is commonly involved in persons with rheumatoid arthritis (RA). Although 2D measurements have long been used in the evaluation of cervical lesions caused by RA, 2D measurements are limited in their effectiveness for detecting subtle and complex morphological and kinematic changes. The purpose of this study was to elucidate the 3D kinematics of the upper cervical spine in RA and the relationship between 3D morphological changes and decreased segmental rotational motion., Methods: Twenty-five consecutive patients (2 men and 23 women, mean age 63.5 years, range 42-77 years) with RA (the RA group) and 10 patients (5 men and 5 women, mean age 69.9 years, range 57-82 years) with cervical spondylosis and no involvement of the upper cervical spine (the control group) underwent 3D CT of the cervical spine in 3 positions (neutral, 45° head rotation to the left, and 45° head rotation to the right). The segmental rotation angle from the occiput (Oc) to C-2 was calculated for each participant using a voxel-based registration method, and the 3D destruction of articular facets was quantified using the authors' own parameter, the articular facet index., Results: The segmental rotation angle was significantly smaller at C1-2 and larger at Oc-C1 in the RA group compared with the control group. The degree of the destruction of the articular facet at C-1 and C-2 correlated with the segmental rotation angle., Conclusions: In vivo 3D kinematics of the upper cervical spine during head rotation in patients with RA were accurately measured, allowing quantification of the degree of joint destruction for the first time. Joint destruction may play an important role in decreasing segmental motion of the upper cervical spine in RA.

Study Design: Retrospective study., Objective: We sought to determine the long-term outcomes of laminoplasty versus anterior decompression and fusion in the treatment of cervical myelopathy caused by ossification of the posterior longitudinal ligament (OPLL) and to ascertain what factors should be considered in selecting appropriate surgical procedure., Summary of Background Data: There are little data about long-term results of cervical myelopathy due to OPLL with an occupying ratio 60% or more., Methods: We retrospectively studied 27 patients having OPLL with an occupying ratio 60% or more and a follow-up period of at least 2 years. Clinical outcome was evaluated using Japanese Orthopaedic Association scores and recovery rates (≥75%, excellent; 50%-74%, good; 25%-50%, fair; and <25%, poor)., Results: The mean age and the mean duration of follow-up were 57 years and 10.2 years. The mean Japanese Orthopaedic Association score was 9.3 before surgery and 12.4 at the final follow-up examination. There were 15 patients in the laminoplasty group (LAM group) and 12 patients in the anterior decompression and fusion group (ADF group). The ADF group had a significantly better recovery rate at final evaluation (53% vs. 30%; P = 0.04), a longer duration of surgery (314 vs. 128 min; P < 0.01), and greater blood loss (600 vs. 240 mL; P < 0.01) than did the LAM group. In the LAM group, 4 patients with excellent or good results had a significantly larger degree of cervical lordosis (30°vs. 10°; P = 0.002) than others., Conclusion: The ADF group had a significantly better recovery rate than the LAM group, although the degree of surgical invasiveness was high. ADF is generally recommended for OPLL with an occupying ratio 60% or more., Level of Evidence: 3.

Study Design: Retrospective cohort analysis., Objective: To clarify the effect of biological agents (BAs) on the development and progression of cervical lesions in patients with rheumatoid arthritis (RA) and to identify biomarkers that accurately predict disease progression., Summary of Background Data: The introduction of BAs changed the paradigm of RA treatment. However, their effects on cervical lesions in patients with RA have not been studied., Methods: Ninety-one subjects who had received BAs for 2 years or more were enrolled. Mean radiographical interval was 3.9 years. Disease activity was evaluated by disease activity score-C-reactive protein levels, and matrix metalloproteinase-3 levels. Cervical lesions were defined as an atlantodental interval more than 3 mm for atlantoaxial subluxation (AAS), Ranawat value less than 13 mm for vertical subluxation (VS), and anterior or posterior listhesis more than 2 mm for subaxial subluxation. Disease progression was defined radiographically as an increase in the atlantodental interval more than 2 mm for AAS, a decrease in both Ranawat and Redlund-Johnell values more than 2 mm for VS, and an increase in listhesis more than 2 mm for subaxial subluxation. We used multivariate regression techniques to assess predictors of disease progression., Results: Baseline radiographical evaluation showed no pre-existing cervical lesion in 44 patients, AAS in 29, and VS in 18. Radiological progression occurred in 7% patients without baseline lesions, 79% in the AAS group, and 72% in the VS group. The incidence of progression was significantly lower in patients without lesions at baseline. Multivariate regression analysis demonstrated pre-existing cervical lesions, disease activity score-C-reactive protein levels at baseline and metalloproteinase-3 levels at final visit as good predictors of RA progression., Conclusion: BAs prevented de novo cervical lesions in patients with RA but failed to control progression in patients with pre-existing cervical lesions. Disease activity score-C-reactive protein levels at baseline were related to pre-existing joint destruction, and metalloproteinase-3 levels accurately predicted ongoing bone destruction during BA treatment., Level of Evidence: 3.

Background: Anterior decompression with fusion (ADF) for patients with cervical ossification of the posterior longitudinal ligament (OPLL) is reportedly associated with a higher incidence of complications than is laminoplasty. However, the frequency of perioperative complications associated with ADF for cervical OPLL has not been fully established. The purpose of this study was to investigate the incidence of perioperative complications, especially neurological complications, following ADF performed to relieve compressive cervical myelopathy due to cervical OPLL., Methods: Study participants comprised 150 patients who had undergone ADF for cervical OPLL at 27 institutions between 2005 and 2008. Perioperative--especially neurological--complications occurring within 2 weeks after ADF were analyzed. Preoperative imaging findings, including Cobb angle, between C2 and C7 and occupying ratio of OPLL were investigated. Multivariate analysis with logistic regression was performed to identify independent risk factors for neurological complications., Result: Three patients (2.0 %) showed deterioration of lower-extremity function after ADF. One of the three patients had not regained their preoperative level of function 6 months after surgery. Upper-extremity paresis occurred in 20 patients (13.3 %), five of whom had not returned to preoperative levels 6 months after surgery. Patients with upper-extremity paresis showed significantly higher occupying ratios of OPLL, greater blood loss, longer operation times, fusion of more segments, and higher rates of cerebrospinal fluid leakage than those without paresis. Independent risk factors for upper-extremity paresis were a high occupying ratio of OPLL and large blood loss during surgery., Conclusions: The incidences of deterioration in upper- and lower-extremity functions were 13.3 % and 2.0 %, respectively. Patients with a high occupying ratio of OPLL are at higher risk of developing neurological deterioration.

Study Design: A retrospective cohort analysis., Objective: To determine the effect of biological agents (BAs) on the development and progression of cervical spine lesions and identify predictors of lesion progression., Summary of Background Data: The introduction of BAs has facilitated advances in the treatment of rheumatoid arthritis (RA). BAs reduce disease activity and limit structural joint damage. However, the effect of BAs on cervical spine lesions remains unclear., Methods: Thirty-eight subjects who received more than 2 years of continuous BA treatment were enrolled. The mean x-ray interval was 4.4 years. RA activity was evaluated by disease activity score (DAS)-C reactive protein (CRP) and matrix metalloproteinase (MMP)-3. Radiographical definitions of cervical lesions were atlanto-dental interval (ADI) more than 3 mm for atlanto-axial subluxation (AAS), Ranawat value less than 13 mm for vertical subluxation (VS), and anterior or posterior listhesis more than 2 mm for subaxial subluxation (SS). Definitions of radiographical progression were an increase of ADI more than 2 mm for AAS, a decrease of both Ranawat and Redlund-Johnell values more than 2 mm for VS, and an increase of listhesis more than 2 mm for SS., Results: RA activity responded dramatically to BA therapy (DAS-CRP from 4.3 to 2.3, P < 0.01; MMP-3 from 207.9 ng/mL to 105.6 ng/mL, P < 0.01). Baseline radiographical evaluation showed no pre-existing cervical spine lesions in 12 cases, AAS in 15 cases, and VS in 11 cases. Radiological progression was found in 1 (8%) patient in the no lesion group, 12 patients (80%) in the AAS group, and 9 patients (80%) in the VS group. The incidence of progression was significantly lower in the no lesion group compared with the other groups. Multivariate regression analysis showed that the presence of pre-existing cervical lesions was the single greatest predictor of progression., Conclusion: BAs prevented the development of de novo cervical spine lesions in patients with RA, but failed to inhibit progression of pre-existing RA lesions.

Object: Double-door laminoplasty using hydroxyapatite (HA) spacers has been widely performed for compressive cervical myelopathy and has provided good neurological outcome. Although HA spacers are used for preventing reclosure of the opened laminae, they are often displaced or dislocated from their original position. The authors investigated the incidence and patterns of postoperative HA spacer displacement to determine the reasons for this unfavorable event., Methods: Eighty-six patients with compressive myelopathy underwent double-door laminoplasty in which a total of 278 HA spacers were used. The displacement of HA spacers and opened laminae were assessed using postoperative lateral radiographs and CT scans., Results: Postoperative dorsal migration > 2 mm was found in 116 (42%) of 278 implanted HA spacers. In addition, 33 (38%) of 86 HA spacers rotated > 10 degrees and 29 (34%) of the 86 opened laminae tilted > 10 degrees. Moreover, deformation of the newly formed spinal canal was observed in 51 (59%) of 86 cases, and bone fusion between the HA spacer and spinous process was achieved in only 15 (8.7%) of 172 cases. Neurological worsening and neck pain, however, were not associated with displacement of HA spacers or deformation of the spinal canal., Conclusions: In double-door laminoplasty, postoperative displacement of the HA spacer with deformation of the enlarged spinal canal occurred frequently. Hydroxyapatite spacers tend to become displaced after surgery. Placing the HA spacer at the base of the spinous process close to the dura mater may prevent postoperative displacement.

We evaluated 30 patients with cervical myelopathy before and after decompressive surgery and compared them with 42 healthy controls. All were asked to grip and release their fingers as rapidly as possible for 15 seconds. Films recorded with a digital camera were divided into three files of five seconds each. Three doctors independently counted the number of grip and release cycles in a blinded manner (N1 represents the number of cycles for the first five-second segment, N2 for the second and N3 for the third). N1 [corrected] N2 and N3 of the pre-operative group were significantly fewer than those of the control group, and the post-operative [corrected] group's results were significantly fewer [corrected] than those of the pre-operative group. In the control group, the numbers decreased significantly with each succeeding five-second interval (fatigue phenomenon). In the pre-operative myelopathy group there was no significant difference between N1 and N2 (freezing phenomenon). The 15-second test is shown to be reliable in the quantitative evaluation of cervical myelopathy. Although it requires a camera and animation files, it can detect small changes in neurological status because of its precise and objective nature.