古矢 丈雄

BACKGROUND: According to most of the commonly used classification systems for subaxial spine injuries, unilateral and minimally displaced facet fractures without any sign of a spinal cord injury would be directed to non-operative management. However, the failure rate of non-operative treatment varies from 20 to 80%, and no consensus exists with regard to predictors of failure after non-operative management. CASE PRESENTATION: Case 1 is a patient with a unilateral facet fracture. The patient had only numbness in the right C6 dermatome but failed non-operative treatment, which resulted in severe spinal cord injury. Case 2 is a patient who had a similar injury pattern as case 1 but presented with immediate instability and underwent fusion surgery. Both patients had a minimally displaced unilateral facet fracture accompanied by disc injury and blunt vertebral artery injury, which are possible signs indicating significant instability. CONCLUSIONS: This is the first report of an isolated unilateral facet fracture that resulted in catastrophic spinal cord injury. These two cases illustrate that an isolated minimally displaced unilateral facet fracture with disc injury and vertebral artery injury were associated with significant instability that can lead to spinal cord injury.

BackgroundSeveral authors have reported favorable results in low back pain (LBP) for patients with lumbar disc herniation (LDH) treated with discectomy. However, detailed changes over time in the characteristics and location of LBP before and after discectomy for LDH remain unclear. To clarify these points, we conducted an observational study to determine the detailed characteristics and location of LBP before and after discectomy for LDH, using a detailed visual analog scale (VAS) bilaterally.MethodsWe included 65 patients with LDH treated by discectomy in this study. A detailed VAS for LBP was administered with the patient under 3 different conditions: in motion, standing, and sitting. Bilateral VAS was also administered (affected versus opposite side) for LBP, lower extremity pain (LEP), and lower extremity numbness (LEN). The Oswestry Disability Index (ODI) was used to quantify clinical status. Changes over time in these VAS and ODI were investigated. Pfirrmann grading and Modic change as seen by magnetic resonance imaging (MRI) were reviewed before and 1year after discectomy to determine disc and endplate condition.ResultsBefore surgery, LBP on the affected side while the patients were in motion was significantly higher than LBP while they were sitting (p=0.025). This increased LBP on the affected side in motion was improved significantly after discectomy (p<0.001). By contrast, the residual LBP while sitting at 1year after surgery was significantly higher than the LBP while they were in motion or standing (p=0.015). At 1year following discectomy, residual LBP while sitting was significantly greater in cases showing changes in Pfirrmann grade (p=0.002) or Modic type (p=0.025).ConclusionsImprovement of LBP on the affected side while the patient is in motion suggests that radicular LBP is improved following discectomy by nerve root decompression. Furthermore, residual LBP may reflect increased load and pressure on the disc and endplate in the sitting position.

Advanced glycation end-products (AGEs) have been reported as a possible biomarker of ageing and metabolic diseases; however, its role in the clinical progression of these diseases remains unclear. We aimed to evaluate how AGEs are associated with clinical symptoms and comorbidities in lower back pain (LBP) patients. This prospective cohort study enrolled 636 LBP patients. They were subjected to quantified AGE (qAGE) analysis using skin autofluorescence, and their clinical symptoms and comorbidities, such as diabetes, renal failure with haemodialysis treatment, and osteoporosis, were measured. LBP, lower extremity pain, and numbness were evaluated using a visual analogue scale (VAS). The measured qAGE was significantly higher in subjects with any comorbidity. Age also showed a strong positive correlation with qAGE. qAGE and VAS for leg numbness were positively correlated. Furthermore, in LBP patients under 50-years-old, qAGE was positively correlated with VAS for LBP, lower extremity pain, and numbness. In conclusion, qAGE, as measured by skin autofluorescence measurement, was significantly higher in LBP patients with diabetes and dialysis, as well as in osteoporosis patients. Furthermore, qAGE showed potential as a biomarker for LBP, lower extremity pain, and numbness in patients under 50-years-old. If accumulated AGEs are identified at a young age, researchers should be vigilant for the development of osteoporosis and LBP-related clinical symptoms later in life. (C) 2020 Elsevier Ltd. All rights reserved.

Lumbar lateral interbody fusion (LLIF) has been gaining popularity among the spine surgeons dealing with degenerative spinal diseases while LLIF on L5-S1 is still challenging for its technical and anatomical difficulty. OLIF51 procedure achieves effective anterior interbody fusion based on less invasive anterior interbody fusion via bifurcation of great vessels using specially designed retractors. The technique also achieves seamless anterior interbody fusion when combined with OLIF25. A thorough understanding of the procedures and anatomical features is mandatory to avoid perioperative complications.

Background: The optimal surgical procedure for the treatment of cervical spondylotic myelopathy (CSM) remains controversial because there are few comprehensive studies that have investigated the surgical methods. Therefore, we conducted a systematic review and meta-analysis to evaluate evidence in the literature and to compare the surgical outcomes between anterior decompression with fusion (ADF) and laminoplasty, which are representative procedures for CSM.Methods: An extensive literature search was performed using PubMed, Embase, and the Cochrane Library to identify comparative studies of ADF and laminoplasty for CSM. The language was restricted to English, and the publication period was from January 2001 to July 2019. We only included studies of CSM and excluded studies that involved patients with ossification of the posterior longitudinal ligament and treatments with posterior instrumented fusion. We extracted outcomes from the studies, such as preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, cervical alignment, surgical complications and reoperation rates. Then, a meta-analysis was performed on these surgical outcomes.Results: Nine studies were obtained, and the quality of the studies was acceptable. In the meta-analysis, the preoperative JOA score was similar between the ADF and laminoplasty groups. The postoperative JOA scores and neurological recovery rates were not different between the ADF and laminoplasty groups. ADF exhibited more favorable results than laminoplasty in terms of postoperative cervical alignment. In contrast, overall complications were more frequently observed in the ADF group than in the laminoplasty group, leading to higher rates of reoperation. However, postoperative neck pain was more frequently observed in the laminoplasty group than in the ADF group.Conclusions: This systematic review and meta-analysis showed both the merits and shortcomings of ADF and laminoplasty. ADF and laminoplasty showed similar results in terms of neurological recovery. Postoperative cervical lordosis was better preserved with ADF than with laminoplasty. However, ADF was associated with a higher incidence of surgical complications than laminoplasty. (C) 2020 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

This study aimed to clarify whether ossification predisposition influences clinical symptoms including pain, restriction of activities of daily living, and quality of life in patients with cervical ossification of the posterior longitudinal ligament (OPLL). Cervical ossification predisposition potentially causes neurologic dysfunction, but the relationship between clinical symptoms and radiologic severity of OPLL has not yet been investigated. Data were prospectively collected from 16 institutions across Japan. We enrolled 239 patients with cervical OPLL. The primary outcomes were patient-reported outcomes, including visual analog scale (VAS) pain scores and other questionnaires. Whole-spine computed tomography images were obtained, and correlations were investigated between clinical symptoms and radiologic findings, including the distribution of OPLL, the sum of the levels where OPLL was present (OP-index), and the canal narrowing ratio (CNR) grade. The cervical OP-index was Grade 1 in 113 patients, Grade 2 in 90, and Grade 3 in 36. No significant correlations were found between radiologic outcomes and VAS pain scores. The cervical OP-index was associated with lower extremity function, social dysfunction, and locomotive function. The CNR grade was not correlated with clinical symptoms, but Grade 4 was associated with lower extremity dysfunction. Thickness and extension of ossified lesions may be associated with lower extremity dysfunction in cervical OPLL.

＜文献概要＞はじめに 骨粗鬆症患者で最も骨折が多発する部位は椎体であり,年間140万人に新たな脆弱性椎体骨折が発生していると報告されている.脆弱性椎体骨折を受傷すると,強い疼痛による著しいADL低下(活動制限とそれに伴う廃用)が必発である.さらに,Quality of Life Questionnaire of the European Foundation for Osteoporosis(QUALEFFO)を用いて調査した報告では,脆弱性椎体骨折があると身体機能のみならず,社会機能,全体的健康観までもが低下するとも報告されている.つまり,その影響はQOL低下にまで及ぶといえる.したがって,疼痛のみならずADLおよびQOLの観点からも脆弱性椎体骨折に対する適切な治療介入が重要なのはいうまでもない.そこで本稿では,脆弱性椎体骨折に対する痛み治療のストラテジーについて,(1) 一般的な腰痛治療の観点,(2)脆弱性椎体骨折特有の観点といった2つの面から概説する.

Recent reports indicate that oxidative stress is involved in the pathobiology of acute spinal cord injury or compression myelopathy. We conducted an observational study to determine levels of oxidative stress markers in serum from 80 patients who underwent spinal surgery to treat neurological symptoms related to lumbar degenerative disorders. Serum samples were collected before surgery and at 3 months, 6 months, and 1 year after surgery. Derivatives of reactive oxygen metabolites (ROM) in the serum samples were measured to gauge the level of oxidative stress. For preoperative neurological evaluation, patients were assessed for motor weakness in the lower extremities. We divided the patient samples into two groups: ROM decreasing at 1 year after surgery (G group) and ROM increasing at 1 year after surgery (W group). Then, we evaluated clinical outcomes using the visual analog scale and Oswestry disability index (ODI). Among the samples from the 80 enrolled patients, mean ROM levels before surgery increased to 388.5 +/- 92.0, indicating the presence of moderate oxidative stress. The level of ROM gradually decreased after surgery and 1 year after surgery: the levels had significantly decreased to 367.6 +/- 83.3 (p<0.05). In patients who exhibited motor weakness, ROM values were significantly increased compared to those patients who had no motor weakness (p<0.05). In analyses of clinical outcomes, ODI values for the W group 1 year after surgery were significantly higher than those for the G group (p<0.05). Moderate oxidative stress was present in patients who had lumbar degenerative disorders and the degree of oxidative stress gradually improved within 1 year after surgery. The clinical results suggest that neurogenic oxidative stress can be mitigated by surgery for patients with lumbar degenerative disorders, and residual oxidative stress reflects poor surgical outcomes.

STUDY DESIGN: A retrospective case-control study. OBJECTIVE: The objective of this study was to assess mid-term surgical outcomes after posterior decompression with instrumented fusion (PDF) in patients with K-line (-) type cervical ossification of the posterior longitudinal ligament (OPLL). SUMMARY OF BACKGROUND DATA: The poor surgical outcome for K-line (-) type cervical OPLL can result from posterior decompression alone. MATERIALS AND METHODS: We reviewed cases of K-line (-) type cervical OPLL in 24 patients who underwent PDF in our institute from 2002 to 2014. As a control, we used K-line (-) type cervical OPLL in 9 patients who underwent laminoplasty before 2002 (LMP group). The neurological status and radiographic findings were evaluated retrospectively. RESULTS: The preoperative Japanese Orthopedic Association score was 7.9±2.4 points in the PDF group and 7.4±2.3 points in the LMP group (P=0.584). The postoperative Japanese Orthopedic Association score was 11.7±2.6 points in the PDF group and 9.2±2.0 points in the LMP group at a 5-year follow-up (P=0.008). The recovery rate on average was 39.0% in the PDF group and 14.9% in the LMP group at a 5-year follow-up (P=0.037). The range of motion postoperatively at the maximal spinal cord compression level decreased significantly in the PDF group. The C2-C7 angle was 2.7 degrees of kyphosis in the PDF group, whereas 5.5 degrees of kyphosis was found in the LMP group at a 5-year follow-up (P=0.303). The center of gravity of the head-C7 sagittal vertical axis was 40 mm in the PDF group and 43 mm in the LMP group (P=0.936). CONCLUSIONS: The relatively good surgical outcome could be obtained by PDF for patients with K-line (-)-type cervical OPLL. The addition of posterior instrumented fusion eliminated the dynamic factor at the level of maximal spinal cord compression. LEVEL OF EVIDENCE: Level IV.

Background: The optimal surgical procedure for the treatment of cervical spondylotic myelopathy (CSM) remains controversial. Recently, laminectomy/laminoplasty with instrumented fusion (LAMF) has been increasingly applied to treat CSM. However, few comprehensive studies have compared anterior decompression with fusion (ADF) and LAMF. Therefore, we conducted a meta-analysis to evaluate the evidence in the literature and to compare the surgical outcomes between the 2 procedures. Since the surgical outcomes and risks differ between patients with CSM and ossification of the posterior longitudinal ligament (OPLL) and between only posterior decompression and decompression with fusion treatments, we excluded patients with OPLL and patients with only posterior decompression in this review.Methods: An extensive literature search was performed using PubMed, Embase, and the Cochrane Library to identify comparative studies of ADF and LAMF for the treatment of CSM. The language was restricted to English, and the publication period was from January 2001 to July 2019. We only included studies about CSM and excluded studies that involved patients with ossification of the posterior longitudinal ligament and with the treatment of posterior decompression without fusion. We extracted outcomes from the studies, such as preoperative and postoperative Japanese Orthopaedic Association (JOA) scores, neck disability index (NDI) scores, cervical alignment data, and surgical complications. Then, a meta-analysis was performed on these surgical outcomes.Results: Eleven studies were obtained, and the quality of the studies was acceptable. In the meta analysis, the preand postoperative JOA scores were similar between the ADF and LAMF groups. The ADF group exhibited more favorable results than the LAMF group in terms of postoperative cervical alignment and the NDI. Overall complications were similar between the ADF and LAMF groups; however, C5 palsy was more frequently observed in the LAMF group than in the ADF group.Conclusions: While the ADF and LAMF groups demonstrated similar results in terms of neurological recovery, postoperative cervical lordosis and NDI scores were more favorable with ADF than with LAMF.The overall complication rate was similar between the ADF and LAMF groups. Surgeons should understand the merits and shortcomings of both procedures when deciding on a surgical procedure. (C) 2020 The Japanese Orthopaedic Association. Published by Elsevier B.V. All rights reserved.

STUDY DESIGN: Prospective multicenter study. OBJECTIVE: The aim of this study was to compare the clinical and radiographic results of laminoplasty (LAMP), anterior decompression with fusion (ADF), and posterior decompression with fusion (PDF) for degenerative cervical myelopathy (DCM). SUMMARY OF BACKGROUND DATA: Although ADF, LAMP, and PDF have been performed for DCM, little is known about the difference in impact of these surgical treatments on clinical and radiographic outcomes. METHODS: We prospectively enrolled patients who were scheduled for surgery for DCM and compared the clinical and radiographic results of ADF, LAMP, and PDF. RESULTS: In total, 171 patients completed the 1-year follow-up. Regarding clinical outcomes, the Japanese Orthopedic Association score for the assessment of cervical myelopathy (C-JOA score), European Quality of Life-5 Dimensions (EQ-5D), and Neck Disability Index (NDI) scores improved in all groups postoperatively. However, no significant differences were found in C-JOA, EQ-5D, and NDI scores and recovery rate among the groups. Regarding radiographic parameters, although the operation had no effect on cervical lordosis (CL) and the C2-7 sagittal vertical axis (SVA) in the ADF group, they worsened in the LAMP and PDF group. Although there were no significant differences in any preoperative radiographic parameters within the ADF and LAMP group, CL was significantly lower and the C2-7 SVA was significantly higher in the nonrecovery group within the PDF group. Logistic regression analysis showed that preoperative lower CL was an independent risk factor for poor recovery in the PDF group. CONCLUSION: Although groups showed no significant differences in clinical outcomes, cervical alignment worsened after surgery in the LAMP and PDF groups. Within the PDF group, lower CL was an independent risk factor for poor recovery. Therefore, the indications for PDF in DCM patients with preoperative kyphotic alignment should be carefully considered. LEVEL OF EVIDENCE: 3.

STUDY DESIGN: Retrospective cohort study. OBJECTIVE: To clarify the poor patient satisfaction after lumbar spinal surgery in elderly patients. SUMMARY OF BACKGROUND DATA: As the global population continues to age, it is important to consider the surgical outcome and patient satisfaction in the elderly. No studies have assessed patient satisfaction in elderly patients undergoing surgical treatment and risk factors for poor satisfaction in elderly patients after lumbar spinal surgery. MATERIALS AND METHODS: A retrospective multicenter survey was performed in 169 patients aged above 80 years who underwent lumbar spinal surgery. Patients were followed up for at least 1 year after surgery. We assessed patient satisfaction from the results of surgery by using a newly developed patient questionnaire. Patients were assessed by demographic data, surgical procedures, complications, reoperation rate, pain improvement, and risk factors for poor patient satisfaction with surgery for lumbar spinal disease. RESULTS: In total, 131 patients (77.5%, G-group) were satisfied and 38 patients (22.5%, P-group) were dissatisfied with surgery. The 2 groups did not differ significantly in baseline characteristics and surgical data. Postoperative visual analog scale score for low back pain and leg pain were significantly higher in the P-group than in the G-group (low back pain: G-group, 1.7±1.9 vs. P-group, 5.2±2.5, P<0.001; leg pain: G-group, 1.4±2.0 vs. P-group, 5.5±2.6, P<0.001). Multivariate regression analysis revealed that postoperative vertebral fracture (P=0.049; odds ratio, 3.096; 95% confidence interval, 1.004-9.547) and reoperation (P=0.025; odds ratio, 5.692; 95% confidence interval, 1.250-25.913) were significantly associated with the patient satisfaction after lumbar spinal surgery. CONCLUSIONS: Postoperative vertebral fracture and reoperation were found to be risk factors for poor patient satisfaction after lumbar spinal surgery in elderly patients, which suggests a need for careful treatment of osteoporosis in addition to careful determination of surgical indication and procedure in elderly patients. LEVEL OF EVIDENCE: Level III.

PURPOSE: To elucidate the independent preoperative factors that have a significant impact on poor surgical outcome after laminoplasty for K-line (+) ossification of the posterior longitudinal ligament (OPLL). Analyses in K-line (+) patient population can exclude the influence by mal-alignment and thick OPLL, both of which are well known two major factors that have significant impact on clinical outcome. METHODS: The present study included 72 patients (50 male and 22 female) who underwent laminoplasty for K-line (+) cervical OPLL and were followed-up for at least 1 year. Recovery of Japanese Orthopedic Association score (JOA score) for cervical myelopathy was used as the measure of clinical outcome. For radiographic assessment, the type of OPLL, the maximum OPLL occupation ratio, the C2-C7 angle, and the segmental range of motion at the peak of OPLL (segmental ROM) were assessed. To elucidate the factors that are significantly associated with a poor clinical outcome after laminoplasty for K-line (+) OPLL, statistical analyses were conducted. RESULTS: The mean preoperative JOA score was 8.9 points and improved to 12.8 points after surgery. The recovery of JOA score was 47 ± 35%. Stepwise logistic regression following univariate analyses revealed that preoperative segmental ROM at the peak of OPLL is an independent factor associated with a poor outcome (p = 0.04, odds ratio = 1.15). CONCLUSIONS: Large preoperative segmental ROM at the peak of the OPLL is an independent factor that has significant impact on poor surgical outcome after laminoplasty for K-line (+) OPLL.

BACKGROUND: Ossification of the posterior longitudinal ligament of the spine (OPLL) is characterized by heterotopic bone formation in the posterior longitudinal ligament of the spine. We know that the size and distribution of the ossified lesions in patients with OPLL are different in each case. However, the characteristics of the patients with radiologically severe cervical OPLL remain unknown. METHODS: The participants of our study were symptomatic patients with cervical OPLL who were diagnosed by standard radiographs of the cervical spine. Whole-spine CT data and demographic data such as age and sex were obtained from 20 institutions belonging to the Japanese Multicenter Research Organization for Ossification of the Spinal Ligament. According to the number of the levels involved by OPLL, we stratified the patients into two subgroups: severe group (S-group) and non-severe group (NS-group) to delineate the characteristics of radiologically severe patients with cervical OPLL. We also evaluated the most compressed level and the degree of occupying ratio of cervical spinal canal by OPLL at the most compressed level. RESULTS: A total of 234 patients with a mean age of 65 years were recruited. The S-group consisted of 48 patients (21%, 12 females and 36 males) and the NS-group consisted of 92 patients (79%, 22 females and 70 males). The mean age of males in the S-group (68 years old) was significantly higher than that of males in the NS-group (64 years old); however there was no significant difference in the mean age in females between the S-group (69 years old) and the NS-group (66 years old). No significant difference of body mass index, ossification of the nuchal ligament-positivity and presence of diabetes mellitus were found between the S- and the NS-group. CONCLUSIONS: It is likely that the manner of extension of cervical OPLL is different between male and female patients.

BACKGROUND: Central sleep apnea (CSA) due to occipitocervical compression myelopathy is an extremely rare condition. Here we report a case of surgical treatment for CSA due to occipitocervical compression myelopathy in a patient with Klippel-Feil syndrome.CASE DESCRIPTION: A 60-year-old man had become aware of a gradually progressive clumsiness and gait disturbance without any cause of injury 5 years before. He had complicated respiratory discomfort during sleep for the previous month and visited our hospital. Neurologic examination revealed severe myelopathy. Polysomnography showed CSA and Cheyne-Stokes respiration. Imaging findings showed C2-3 vertebral fusion and severe spinal cord compression caused by hypoplasia of the C1 posterior arch complicated by an anomaly of the vertebral artery. We diagnosed the patient with CSA due to occipitocervical compression myelopathy complicated by Klippel-Feil syndrome. After a simulation using a full-scale 3-dimensional model, resection of the C1 posterior arch and C4-5 laminoplasty was performed. After surgery, both clumsiness and gait disturbance gradually improved. Polysomnography 1 month after surgery showed that the CSA and the Cheyne-Stokes respiration disappeared.CONCLUSIONS: Although a recent report has indicated the cause of sleep apnea in patients with rheumatoid arthritis and occipitocervical disorders as obstructive sleep apnea, a significant improvement of CSA was observed with decompression surgery in this case. Appropriate surgical planning resulted in a favorable outcome.