牧 聡

かつて腰痛疾患の85%を占めると謳われた非特異的腰痛の病態は,近年の医学研究の推進とともに解明されつつある。慢性疼痛の機序には腰痛疾患患者の約30%が罹患する神経障害性疼痛の概念が重要であり,特に臀部痛の存在は神経障害性疼痛の可能性を示唆する。椎間板性腰痛は変性椎間板で産生される炎症性サイトカインおよび異常感覚神経の伸長など複数の分子生物学的機序を介して慢性腰痛の一端を担い,これに基づくブロック療法等が報告されている。(著者抄録)

The purpose of this study was to try oblique lateral interbody fusion (OLIF) using percutaneous pedicle screws (PPS) with mobility. Twelve patients who underwent single-level OLIF were observed for at least one year. These included 6 patients with conventional PPS (rigid group), and 6 with movable PPS (semi-rigid group). Mobile PPS used cosmicMIA, which is a load sharing system. The anterior and posterior disc height, screw loosening and bone healing period, and implant failure were evaluated at final observation by CT. Moreover, the stress on the vertebral body-cage, on the vertebral body-screw/rod and on the bone around the screw was estimated using a three-dimensional finite element assessment in both groups. There was no significant difference in surgical time, amount of bleeding, JOA score, or low back pain VAS between groups. There were no differences between groups in anterior and posterior disc height, screw loosening, and implant failure at final observation. The bone healing period was significantly shorter in the semi-rigid screw group (18.3 months vs 4.8 months, p = 0.01). The finite element analysis showed that the lower stress on the rod/screw would contribute to fewer implant fractures and that lower stress on the bone around the screw would reduce screw loosening, and that higher compressive force on the cage would promotes bone healing. OLIF combined with a movable screw accelerated bone healing by nearly 75%. We conclude that mobile PPS in combination with OLIF promotes bone healing and can be a better vertebral fusion technique.

STUDY DESIGN: Retrospective analysis of magnetic resonance imaging (MRI). OBJECTIVE: The aim of this study was to evaluate the performance of our convolutional neural network (CNN) in differentiating between spinal schwannoma and meningioma on MRI. We compared the performance of the CNN and that of two expert radiologists. SUMMARY OF BACKGROUND DATA: Preoperative discrimination between spinal schwannomas and meningiomas is crucial because different surgical procedures are required for their treatment. A deep-learning approach based on CNNs is gaining interest in the medical imaging field. METHODS: We retrospectively reviewed data from patients with spinal schwannoma and meningioma who had undergone MRI and tumor resection. There were 50 patients with schwannoma and 34 patients with meningioma. Sagittal T2-weighted magnetic resonance imaging (T2WI) and sagittal contrast-enhanced T1-weighted magnetic resonance imaging (T1WI) were used for the CNN training and validation. The deep learning framework Tensorflow was used to construct the CNN architecture. To evaluate the performance of the CNN, we plotted the receiver-operating characteristic (ROC) curve and calculated the area under the curve (AUC). We calculated and compared the sensitivity, specificity, and accuracy of the diagnosis by the CNN and two board-certified radiologists. RESULTS: . The AUC of ROC curves of the CNN based on T2WI and contrast-enhanced T1WI were 0.876 and 0.870, respectively. The sensitivity of the CNN based on T2WI was 78%; 100% for radiologist 1; and 95% for radiologist 2. The specificity was 82%, 26%, and 42%, respectively. The accuracy was 80%, 69%, and 73%, respectively. By contrast, the sensitivity of the CNN based on contrast-enhanced T1WI was 85%; 100% for radiologist 1; and 96% for radiologist 2. The specificity was 75%, 56, and 58%, respectively. The accuracy was 81%, 82%, and 81%, respectively. CONCLUSION: We have successfully differentiated spinal schwannomas and meningiomas using the CNN with high diagnostic accuracy comparable to that of experienced radiologists. LEVEL OF EVIDENCE: 4.

Atlantoaxial rotatory fixation (AARF) in an adult without any trauma is an extremely rare condition. Here we report a case of surgical treatment for existing atlantoaxial rotatory fixation in an adult with spastic torticollis. A 50-year-old man had become aware of torticollis without any cause of injury 6 weeks before he visited our hospital, where he presented with a one-week history of severe neck pain. Based on the local and imaging findings, we diagnosed him as having existing AARF of Fielding classification type I. The AARF was not reduced by 3 weeks of Glisson traction. Thus, we performed C1-C2 posterior fusion surgery 3 months after his initial visit. Although CT findings just after surgery showed that the C1-2 facet subluxation was reduced, the complaint of torticollis was not improved, with scoliosis at the middle to lower cervical level because of left sternocleidomastoid hypertonia. Administration of diazepam was initiated 2 weeks after surgery and botulinum toxin injections to the left sternocleidomastoid were added 2 months after surgery under the neurological diagnosis of spastic torticollis. As a result, the complaint of his torticollis was significantly improved 3 months after surgery. There were no relapses of the torticollis and complete fusion of the C1-C2 laminae was observed at the 2-year final follow-up. Surgical treatment for AARF in an adult should be considered if the diagnosis of AARF is delayed. In addition, appropriate treatment for spastic torticollis applied after surgery resulted in a favorable outcome of this case.

Previous studies have reported the utility of diffusion tensor imaging (DTI) as an imaging biomarker for the severity of myelopathy and subsequent surgical outcome in patients with degenerative cervical myelopathy (DCM). We hypothesized that DTI may reflect neurological recovery following surgery. The purpose of this study was to evaluate the ability of DTI to assess the post-operative alteration of neural status in patients with DCM as well as to predict post-operative recovery. We enrolled 15 patients with DCM who underwent decompression surgery. The Japanese Orthopaedic Association (JOA) score was evaluated before and 1 year after surgery. The participants were examined using DTI on a 3.0 T magnetic resonance scanner before, and 1 year after surgery. Fractional anisotropy (FA) and mean diffusivity (MD) were assessed for both time points. The correlations between the pre- and post-operative FA and MD values and the pre- and post-operative JOA scores were analyzed. Although the JOA score improved significantly after surgery from 8.9 to 12.3, there was no significant change between the pre- and post-operative FA and MD values. The post-operative outcomes after 1 year moderately correlated with the pre-operative FA values (Spearman's ρ = 0.55, p = 0.03 and Spearman's ρ = 0.56, p = 0.03 for change and recovery rate of the JOA score, respectively). However, there was no correlation between the post-operative FA and post-operative JOA scores nor between MD and clinical outcomes. DTI cannot be utilized as a biomarker for post-operative alterations of neural status of the spinal cord; however, pre-operative DTI may be useful as a predictor of surgical outcomes.

Ossification of the posterior longitudinal ligament (OPLL) can occur throughout the entire spine and can sometimes lead to spinal disorder. Although patients with OPLL sometimes develop physical limitations because of pain, the characteristics of pain and effects on activities of daily living (ADL) have not been precisely evaluated in OPLL patients. Therefore, we conducted a multi-center prospective study to assess whether the symptoms of cervical OPLL are different from those of cervical spondylosis (CS). A total of 263 patients with a diagnosis of cervical OPLL and 50 patients with a diagnosis of CS were enrolled and provided self-reported outcomes, including responses to the Japanese Orthopaedic Association (JOA) Cervical Myelopathy Evaluation Questionnaire (JOACMEQ), JOA Back Pain Evaluation Questionnaire (JOABPEQ), visual analog scale (VAS), and SF-36 scores. The severity of myelopathy was significantly correlated with each domain of the JOACMEQ and JOABPEQ. There was a negative correlation between the VAS score for each domain and the JOA score. There were significantly positive correlations between the JOA score and the Mental Health, Bodily Pain, Physical Functioning, Role Emotional, and Role Physical domains of the SF-36. One-to-one matching resulted in 50 pairs of patients with OPLL and CS. Although there was no significant between-group difference in scores in any of the domains of the JOACMEQ or JOABPEQ, the VAS scores for pain or numbness in the buttocks or limbs were significantly higher in the CS group; however, there was no marked difference in low back pain, chest tightness, or numbness below the chest between the two study groups. The scores for the Role Physical and Body Pain domains of the SF-36 were significantly higher in the OPLL group than in the CS group, and the mean scores for the other domains was similar between the two groups. The results of this study revealed that patients with OPLL were likely to have neck and low back pain and restriction in ADL. No specific type of pain was found in patients with OPLL when compared with those who had CS.

We report a surgically-treated case of a thoracic dumbbell-shaped spinal tumor with contralateral buttock and lower extremity pain. A 72-year-old man was admitted with buttock pain of a right side and right lower extremity pain. A neurological examination demonstrated no motor weakness and no sensory loss of trunk and both lower limbs. Deep tendon reflexes were normal and Babinski signs were negative bilaterally. The right buttock and lower extremity pain was the only initial and major symptom of him. Magnetic resonance（MR） images revealed the presence of a dumbbell-shaped spinal tumor at the left Th9 level. MR image studies for brain, pelvic, and lumbar spine showed no other lesion. We considered that his symptom was caused by the compression of the left spinothalamic tract at thoracic spine level by the spinal tumor. The symptom disappeared immediately after the excision of the spinal tumor. Our experience suggests that thoracic cord compression caused by such as a dumbbell-shaped spinal tumor should be suspected in patients with buttock and lower extremity pain. And the symptom can occur at the contralateral side of the lesion.

<p>K-line（＋/－/＋）型OPLL症例に対し，椎弓形成術（LMP）に局所固定を最大圧迫高位レベルに追加する術式（sPDF）は有用であるかどうか調査するためにLMP群とsPDF群の術後成績を傾向スコアマッチング法にて比較検討した．全29症例中，それぞれ7例ずつマッチングした．JOA改善率と獲得点数はsPDF群で有意に高く，術後成績は改善していた．K-line（＋/－/＋）症例に対し，椎弓形成術に局所固定を最大圧迫高位レベルに追加する方法は有用な術式であると思われる．</p>

Here, we report a case of spinal tuberculosis without elevation of C-reactive protein (CRP) at the initial visit mimicking spinal metastasis. A 70-year-old woman developed progressive paraplegia without a history of injury and came to our hospital for evaluation. Severe compression to the spinal cord with osteolytic destruction of the spinal vertebrae at T6-7 was observed without elevation of CRP. A T4-9 posterior decompression and fusion were performed. Although the pathology revealed no malignant tumor cells, a positron emission tomography-computed tomography (PET-CT) showed upregulation of the thyroid gland and aspiration cytology revealed a thyroid carcinoma. Thus, we diagnosed her with spinal metastases from thyroid carcinoma. Conservative treatment was chosen with the hope of a significant neurologic recovery; however, 9 months after the primary surgery, she returned to our hospital with reprogressive paraplegia. In addition to progression of osteolytic changes to the T5-7 vertebrae, a coin lesion on the right side of the lung and elevation of CRP were observed. Finally, we diagnosed her with spinal tuberculosis based on the results of a CT-guided needle culture. Two-stage surgeries (posterior and anterior) were performed in addition to administering antituberculosis medications. At the 1-year postoperative follow-up evaluation, both neurologic function and laboratory data were improved with T5-9 complete fusion. It is difficult to determine based on imaging findings alone whether osteolytic vertebrae represent spinal metastases or tuberculosis. Even though inflammatory biomarkers, such as CRP, were not elevated, we should consider the possibility of not only spinal metastases but also tuberculosis when planning surgery involving osteolytic vertebrae. In addition, the combination of neurological, imaging, and pathological findings is important for the diagnosis of spinal tuberculosis.

Introduction: Mirogabalin should be equivalent to pregabalin, but with fewer incidences of adverse drug reactions (ADRs). To verify these benefits in actual clinical trials, our study investigated the frequency of ADRs and mirogabalin's analgesic effects during treatment of peripheral neuropathic pain. Methods: This study included 74 patients with lower limb pain. We surveyed patient reports of ADRs during the follow-up period as the primary endpoint and examined the visual analog scale (VAS) reported for lower limb pain as the secondary endpoint (before administration, and two and four weeks after administration). Results: The occurrence of ADR was 27.0%, like the frequency of ADRs in the clinical trials for other disorders. However, the discontinuation rate of administration was 10.8%, which was significantly lower than the frequency of ADR occurrences. When the analgesic effect was assessed, a significant decrease in the temporal change of VAS for lower limb pain was observed before administration, and two and four weeks after administration. Conclusions: In this study, the occurrence of ADRs reported by the patients was like the frequency of ADRs reported in the clinical trials for other disorders. When assessing the analgesic effect, the temporal change of VAS for lower limb pain was found to decrease significantly before administration, and two and four weeks after administration.

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.

BACKGROUND: Recent reports indicate that oxidative stress induced by reactive oxygen species is associated with the pathobiology of neurodegenerative disorders that involve neuronal cell apoptosis. Here we conducted a cross-sectional study to evaluate serum levels of oxidative stress in cervical compression myelopathy. METHODS: Thirty-six serum samples were collected preoperatively from patients treated for acutely worsening compression myelopathy (AM) and chronic compression myelopathy (CM). Serum levels of oxidative stress markers were evaluated by measuring derivatives of reactive oxygen metabolites (ROM), which reflect concentrations of hydroperoxides. ROM in healthy individuals range from 250 to 300 (U. CARR), whereas ROM >340-400 and > 400 define moderate and severe levels of oxidative stress, respectively. Difference of ROM by the cause of disorders whether cervical spondylotic myelopathy (CSM) or cervical ossification of longitudinal ligament (OPLL), correlations between ROM and patient age, body mass index (BMI), history of smoking, existence of diabetes were examined. Neurological evaluations according to Japanese Orthopaedic Association (JOA) scores were performed and correlated with ROM. RESULTS: ROM increased to 349.5 ± 54.8, representing a moderate oxidative stress, in CM samples. ROM increased to 409.2 ± 77.9 in AM samples, reflecting severe oxidative stress which were significantly higher than for CM samples (p < 0.05). There was no significant difference by the cause of disorders (CSM or OPLL). ROM were significantly increased in AM serum samples from female patients versus AM male and CM patients (p < 0.05). There were no correlations between ROM and age, BMI, history of smoking, and existence of diabetes. A negative correlation between ROM and recovery rate of JOA score (R2 = 0.454, p = 0.047) was observed in the AM group. CONCLUSIONS: Although moderate oxidative stress was present in patients with CM, levels of oxidative stress increased in severity in patients with AM. These results suggest that postsurgical neurological recovery is influenced by severe oxidative stress in AM.

Lower limb muscle mass and grip loss may be risk factors for vertebral compression fractures in women. PURPOSE: We examined the relationship between bone mineral density, bone strength, skeletal muscle mass, grip strength, and skin autofluorescence (SAF) in women with osteoporotic vertebral compression fractures (VCF). METHODS: A total of 1039 women (mean age 73.3 years) were included in our study. These included 222 cases of VCF (mean 77.8 years) and 817 controls (mean 72.0 years). Lumbar and femur BMD were measured for all participants using dual-energy X-ray absorptiometry (DXA). Bone strength surrogates, such as cross-sectional area (CSA) of the proximal femur, were evaluated using Advanced Hip Assessment software. SAF was measured with an autofluorescence reader. We used a bioelectrical impedance analyzer (BIA) to analyze body composition, including appendicular skeletal muscle mass index (SMI; appendicular lean mass (kg)/(height (m))2. We measured bone density, geometric parameters related to bone strength, skeletal muscle mass, grip strength, and SAF in both groups. We also examined factors related to vertebral fracture using multiple logistic regression analysis. RESULTS: Women with vertebral fractures had lower SMI (5.55 vs 5.76 kg/m2, p = 0.0006), smaller femoral cross-sectional area (97.20 vs 100.09, p = 0.014), lower grip strength (16.81 vs 19.16 kg, p < 0.0001), and increased skin autofluorescence (2.38 vs 2.25, p = 0.0002) compared to women without fractures. The prevalence of sarcopenia (SMI < 5.75) was 63.51% in VCF subjects and 52.02% in controls, revealing a high prevalence in VCF (p = 0.002). Skeletal muscle mass and grip strength were not significantly different between patients with acute and old VCF, suggesting that low skeletal muscle mass and muscle weakness may exist before fracture. From the multiple logistic regression analysis, lower femoral density (p = 0.0021), CSA (p = 0.0166), leg muscle mass (p = 0.0127), and left arm grip strength (p = 0.0255) were risk factors for vertebral compression fractures; all were negatively correlated with increased vertebral fractures. CONCLUSIONS: Lower limb muscle mass and grip loss may be closely related to the onset of vertebral compression fracture.

＜文献概要＞腰椎前方固定は近年,低侵襲化が進んできた.その中でも,lateral lumbar interbody fusion(LLIF)の特徴は,前方の矯正力が強いため,椎間板性腰痛,腰椎すべり症,成人脊柱変形に応用されている.後側彎症への高い矯正率,狭窄症に対する間接除圧手術が可能であり,術中の神経に低侵襲で,出血が少ないとされている.ここでは間接除圧手術の良好例を示す.しかしながら内臓損傷(腹膜,胸膜,大腸,尿管など),血管損傷などの合併症も報告されており,本稿では尿管損傷に関して述べる.

＜文献概要＞がん患者の増加により,一般整形外科医にとってもがんの既往のある患者やがん治療中の患者を診療する機会は年々多くなっている.がん患者の運動機能を評価する目的で,外来通院中のがん患者に対しロコモ度テストを施行した.立ち上がりテスト,2ステップテストでは健常コントロール群と大きな差を認めなかったが,ロコモ25では有意にロコモ度が高いという結果であった.ロコモ度判定ではロコモ度1の患者が全体の34%(健常群33%),ロコモ度2は56%(健常群22%)と,健常群と比べてがん患者ではロコモの割合が高いことが明らかとなった.

＜文献概要＞はじめに 近年のがん患者数の増加により,腫瘍専門医だけでなく一般整形外科医もがん患者を診療する機会や,がん患者の骨転移診療にたずさわる機会が増加している.本稿では,当科で2016年より開始した骨転移専門外来の診療データをもとに,骨転移集学的治療における整形外科へのニーズと役割について考察した.

腰痛は混合性疼痛の要素を含むが,下肢・臀部痛を呈する場合は神経障害性の可能性が高い。超高齢社会に突入した現代では加えて骨や筋由来の疼痛も着目されつつあり,たとえば骨粗鬆症では骨折等がなくとも病態そのものが惹起する慢性の疼痛発生機序がある。また骨粗鬆症との合併率が高いサルコペニアもADL障害・疼痛をきたしうる。また,腰痛患者の活動データを蓄積・解析した結果,特に急性期での睡眠障害が優位であることが示唆されるなど,運動器慢性疼痛の機序とその評価に対するアプローチは多面化している。(著者抄録)