稲毛 一秀

【目的】ラット筋損傷モデルを用いて圧迫、冷却療法による治療効果を比較した。【方法】8週齢雄性SDラットを用いdrop mass法にてモデル作成し、損傷後3時間にゴムで損傷部を30分圧迫した圧迫群(n=36)、氷で損傷部を30分冷却した冷却群(n=36)、未治療群(n=36)の3群について比較を行った。損傷後3、6、18、24時間、3日、1週、2週の腓腹筋をHE染色で評価した。損傷後3、6、18、24時間の腓腹筋をELISA法にてTNF-αの定量評価を行った。損傷部にフルオロゴールド(FG)を留置し、損傷後3日のL4後根神経節でCGRP(疼痛関連ペプチド)による免疫組織化学染色を行った。【結果】組織では未治療群と比し、圧迫群は損傷後6時間以降で出血や浮腫が少ない傾向にあった。冷却群は、損傷後6時間で出血や浮腫は減少するも、損傷後18時間以降で増強した。損傷後1週で未治療群は筋組織の壊死が残存するも、圧迫群、冷却群は筋線維修復が認められた。サイトカインは、圧迫群は未治療群と比し損傷後3、6、18時間共に低値を示した。特に損傷後6時間で有意に低値であった(P<0.05)。冷却群は未治療群と比し損傷後3、6時間で一過性な上昇を示すも、損傷後18時間では有意に低下した(P<0.05)。L4後根神経節でのFG陽性細胞中のFGとCGRPで二重標識される細胞の割合は、圧迫群、冷却群ともに未治療群と比し有意に低かった(P<0.05)。【考察】圧迫、冷却療法は筋組織修復を促進し、疼痛の遷延化を予防するが、急性期では異なる経時的変化を示し、組織修復過程に差異がある可能性が示唆された。(著者抄録)

OBJECTIVE: To validate the relationship between residual walking ability and monthly care cost as well as long-term care insurance (LTCI) certification level in elderly patients after surgical treatment for hip fractures in Japan. METHODS: Elderly patients aged >75 years who underwent surgical treatment for hip fractures in our hospital were included. The preand post-surgical (6-month) walking ability and LTCI certification and the presence or absence of dementia was determined from medical records and questionnaires. Walking ability was classified into 6 levels used in our daily medical practice. Based on these data, we correlated the relationship between walking ability and the LTCI certification level. Further, based on the official statistics pertaining to the average monthly costs per person at each LTCI certification level, we evaluated the relationship between walking ability and monthly care cost. RESULTS: A total of 105 cases (mean age, 80.2 years; 16 men; 39 patients with dementia) were included. The correlation between walking ability and average monthly cost per person as well as LTCI certification level at 6 months postoperatively (r=0.58) was demonstrated. The correlation was found in both groups with and without dementia. CONCLUSION: The ability to walk reduced the cost of care in elderly patients who experienced hip fracture, regardless of the presence of dementia.

BACKGROUND: The purpose of this study was to validate a diaphyseal femoral fracture model using a finite element analysis (FEA) with mechanical testing in fresh-frozen cadavers. METHODS: We used 18 intact femora (9 right and 9 left) from 9 fresh-frozen cadavers. Specimens were obtained from 5 males and 4 females with a mean age of 85.6 years. We compared a computed tomography (CT)-based FEA model to diaphyseal femoral fracture loads and stiffness obtained by three-point bending. Four material characteristic conversion equations (the Keyak, Carter, and Keller equations plus Keller's equation for the vertebra) with different shell thicknesses (0.3, 0.4, and 0.5 mm) were compared with the mechanical testing. RESULTS: The average fracture load was 4582.8 N and the mean stiffness was 942.0 N/mm from actual mechanical testing. FEA prediction using Keller's equation for the vertebra with a 0.4-mm shell thickness showed the best correlations with the fracture load (R2 = 0.76) and stiffness (R2 = 0.54). Shell thicknesses of 0.3 and 0.5 mm in Keller's equation for the vertebra also showed a strong correlation with fracture load (R2 = 0.66 for both) and stiffness (R2 = 0.50 and 0.52, respectively). There were no significant correlations with the other equations. CONCLUSION: We validated femoral diaphyseal fracture loads and stiffness using an FEA in a cadaveric study.

BACKGROUND: Component design is one of the contributory factors affecting the postoperative flexion angle. The purpose of this study was to compare short-term outcomes of flat surface and medial pivot designs in posterior cruciate-retaining (CR) total knee arthroplasty (TKA). METHODS: A retrospective, case-control, and observational cohort study consisted of matched-pairs of the flat surface design (Hi-Tech Knee II) and the medial pivot design (FINE Knee) in CR-TKA with a two-year follow-up period. RESULTS: Hi-Tech Knee II and FINE knee groups each included 7 males and 38 females. Surgical time was significantly shorter in the FINE Knee group than in the Hi-Tech Knee II group (104.8 min versus 154.9 min, p = 0.001). Estimated total blood loss was significantly lower in the FINE Knee group than in the Hi-Tech Knee II group (654 ml versus 1158 ml, p = 0.001). The postoperative flexion angle was significantly better in the FINE Knee group than in the Hi-Tech Knee II group (119.3 degrees versus 112.5 degrees), and was positively correlated with the preoperative flexion angle. Postoperative Knee Society scores were significantly better in the FINE Knee group than in the Hi-Tech Knee II group (93.0 points versus 85.0 points, p = 0.001), especially for postoperative pain relief (46.0 points versus 39.0 points out of 50, p = 0.001). Complications were not observed in either group over a two-year follow-up period. CONCLUSION: The short-term outcome of the medial pivot design used in CR-TKA was more favorable than the flat surface design, especially for surgical time, estimated total blood loss, postoperative flexion angle, and knee pain.

慢性腰痛の病態は多因子からなり、疼痛機序の観点からは全体で約30%の患者に神経障害性疼痛の関与が考えられる。下肢痛や臀部痛のある症例ではその割合は高く、慢性腰痛における特徴の一つと考えられる。また、腰痛患者の活動量の実態をより正確に把握するため行った日常活動度のデータ蓄積と解析によると、特に急性期での睡眠障害の具現化が示唆された。慢性腰痛の病態を検証するうえでは、今後は活動度も含んだより多面的な検証が有用であると考えられる。(著者抄録)

PURPOSE: Addition of posterior instrumented fusion to laminoplasty (posterior decompression with instrumented fusion: PDF) can improve the surgical outcome of patients with K-line (-) cervical ossification of the longitudinal ligament (OPLL) compared with laminoplasty alone. We sought to elucidate the factors that are significantly associated with a better outcome after PDF for K-line (-) OPLL. METHODS: The present study included 38 patients who underwent PDF for K-line (-) OPLL and were followed up for at least 1 year after surgery. Clinical outcome was assessed using Japanese Orthopedic Association (JOA) scores for cervical myelopathy and the recovery rate was calculated. Patients who belonged to the upper quartile of all the patients according to rank order of the JOA score recovery rate were considered to have a good outcome. The correlations between good outcome, patient factors and imaging assessments were analyzed statistically. RESULTS: Univariate analyses showed that postoperative conversion of K-line from (-) to (+) (p = 0.004), no increase in the sagittal vertical axis from the center of gravity of the head to C7 (p = 0.07), and a lower grade of preoperative intramedullary T2-signal intensity (p = 0.03) were candidates for the association. Stepwise logistic regression analysis revealed that postoperative K-line conversion from (-) to (+) is an independent factor that is significantly associated with a better surgical outcome (p = 0.04). CONCLUSION: Postoperative K-line conversion from (-) to (+) is a factor independently associated with a better surgical outcome. These slides can be retrieved under Electronic Supplementary material.

STUDY DESIGN: Retrospective observational study. PURPOSE: We considered the relationship between spinal alignment and skeletal muscle mass on clinical outcomes following a surgery for lumbar spinal stenosis (LSS). OVERVIEW OF LITERATURE: There are no reports of preoperative factors predicting residual low back pain following surgery for LSS. METHODS: Our target population included 34 women (mean age, 74.4 years) who underwent surgery for LSS. Prior to and 6 months after the surgery, systemic bone mineral density and lean soft tissue mass were measured using dual-energy X-ray absorptiometry. Skeletal muscle mass index (SMI) was calculated as the sum of the arm and leg lean mass in kilograms divided by height in meters squared. The spinal alignment was also measured. Clinical outcomes were evaluated using the Japanese Orthopedic Association scoring system, leg and low back pain Visual Analog Scale, and Roland-Morris Disability Questionnaire (RDQ). Additionally, we examined the bone mineral density, skeletal muscle mass, and spinal alignment before and after the surgery. We used the Spearman correlation coefficient to examine the associations among clinical outcomes, preoperative muscle mass, and spinal alignment. RESULTS: Sarcopenia (SMI <5.46) was observed in nine subjects (26.5%). Compared with normal subjects (SMI >6.12), RDQ was significantly higher in subjects with sarcopenia (p =0.04). RDQ was significantly negatively correlated with SMI (r =-0.42, p <0.05). There was a significant positive correlation between postoperative RDQ and pelvic tilt (PT; r =0.41, p <0.05). SMI and PT were significantly negatively correlated (r =-0.39, r <0.05). CONCLUSIONS: Good postoperative outcomes were negatively correlated with low preoperative appendicular muscle mass, suggesting that postoperative outcomes were inferior in cases of decreased appendicular muscle mass (sarcopenia). Posterior PT due to decreased limb muscle mass may contribute to postoperative back pain, showing that preoperatively reduced limb muscle mass and posterior PT are predictive factors in the persistence of postoperative low back pain.

Background: The K-line, which is a virtual line between the midpoints of the antero-posterior canal diameter at C2 and C7, can be useful for determination of surgical procedures for cervical ossification of the posterior longitudinal ligament (OPLL). Although K-line is originally measured with plain radiogram, computed tomography multiplanar reconstruction (CT-MPR) is applied for K-line measurement by several surgeons. The purpose of the present study was to analyze whether there is a difference in K-lines obtained from radiographs of standing patients and those obtained from CT-MPR images of supine patients. Methods: The present study included 65 patients with cervical OPLL underwent surgical treatment. We investigated the K-line (+ or -) before surgery, measured from lateral cervical spine radiographs taken in standing patients in a neutral position (X-P-based K-line) and CT-MPR mid-sagittal images obtained in supine patients (CT-based K-line). The X-P-based and CT-based K-lines were compared and differences between them were assessed. Results: The-X-P-based K-line was found to be (+) in 35 patients and (-) in 30 patients. Four of 35 patients with an X-P-based K-line (11%) showed a change from K-line (+) to (-) in CT-based K-line measurements. One of 30 patients with an X-P-based K-line (3%) showed a change from (-) to (+) in CT-based measurements. Conclusions: The K-line should be measured with plain radiogram of standing patients because X-P-based K-line and CT-based K-line can be different.

慢性腰痛の原因は多岐に亘るが、その中で特に腰椎椎間板、神経根は、慢性腰痛や坐骨神経痛の主因とされる。歴史的背景から、これらの病態に慢性炎症は深くかかわっていることが示されてきた。椎間板性腰痛の病態は変性した椎間板への感覚神経の侵入とサイトカインを中心とした微小炎症と考えられている。また神経根性疼痛の病態も、慢性炎症と神経のワーラー変性とされている。これ等の機序、新規診断方法、治療法の展開について記載したい。(著者抄録)

整形外科外来通院中の高齢者110例を対象に壁-後頭間距離(WOD)とロコモティブシンドローム(ロコモ)の関連性を検討した。WODはロコモ5と中等度の正の相関、2ステップ値と弱い負の相関を示した。受信者操作特性曲線分析の結果WODのカットオフ値を5cmとすると感度56%、特異度80%でロコモを判別可能であった。これらのことからWODはロコモ早期発見のパラメーターとして臨床応用が可能であると示唆された。(著者抄録)

Objective: The purpose of this study was to investigate transitional changes in the incidence of glucocorticoid-associated osteonecrosis in SLE patients, with a focus on immunosuppressive agent and glucocorticoid consumption. Methods: We retrospectively registered 185 SLE patients with 740 joints, who were newly diagnosed and hospitalized for initial high-dose glucocorticoid therapy from 1986 to 2015. Immunosuppressive agent, glucocorticoid dose, age, sex, organ lesion at hospitalization, complement (C3, C4, CH50) and anti-DNA antibody before initial glucocorticoid therapy, the frequency of use of anticoagulant and antilipidemic drugs, and incidence of osteonecrosis were documented. Results: Based on trends in immunosuppressive agent use, 116 patients treated from 1986 to 1999, before calcineurin inhibitors were introduced, comprised the past group, and 69 patients treated from 2000 to 2015 comprised the recent group. Patient characteristics (age, sex and organ lesion at hospitalization, complement, anti-DNA antibody, the frequency of use of anticoagulant and antilipidemic drugs) were similar between groups. Glucocorticoid doses were significantly lower in the recent group than in the past group (highest daily glucocorticoid dose, 45.7 vs 59.0 mg/day, respectively; dose per weight, 0.88 vs 1.16 mg/day/kg, respectively; and cumulative dose at 3 months, 3118 vs 3985 mg). The incidence of osteonecrosis was significantly lower in the recent group than in the past group (26.4 vs 41.0%, respectively), particularly in the knee (25.4 vs 46.6%, respectively). Conclusion: The incidence of glucocorticoid-associated osteonecrosis in SLE patients decreased in association with a decrease in glucocorticoid administration after introduction of immunosuppressant agents.

STUDY DESIGN: A case-control study. OBJECTIVE: The aim of this study was to investigate the long-term prevalence of the Modic changes and disc degeneration in the nonfused segments of the surgically treated adolescent idiopathic scoliosis (AIS) patients and compare with age- and sex-matched healthy controls. SUMMARY OF BACKGROUND DATA: No studies have looked at the association between Modic changes and low back pain in patients who underwent AIS surgery many years ago. METHODS: Study subjects consisted of 194 patients with AIS who underwent spinal fusion with Harrington instrumentation between 1968 and 1987. Twenty-six patients (AIS group) underwent lumbar magnetic resonance imaging (MRI), whole spine X-ray, and patient-reported outcomes evaluations [Scoliosis Research Society-22 Patient Questionnaire (SRS-22), Oswestry Disability Index (ODI)]. The mean duration of follow-up observation was 36.1 years. The lowest fusion vertebra was used as follows: T12: 2 patients, L1: 4, L2: 11, L3: 6, L4: 2, L5: 1. Twenty-nine healthy age- and sex-matched individuals were selected as a control (CTR) group. RESULTS: On the basis of MRI findings, a significantly higher percentage of subjects showed Modic changes in the AIS group (AIS group: 57.7%, CTR group: 13.8%). There were no significant differences in the percentage of subjects with disc degeneration rated Pfirrmann grade 4 or higher (AIS group: 61.5%, CTR group: 65.5%). SRS-22 scores for function and self-image were significantly lower in the AIS group. ODI was significantly worse in the AIS group. Modic changes in AIS group were found in the concave side of the curve in 61.9%. The magnitude of lumbar coronal curve was found to be a significant risk factor of Modic changes. CONCLUSION: Modic changes were observed in 57.7% of AIS patients 27 years or more after spinal fusion with Harrington instrumentation. The magnitude of lumbar coronal curve was found to be a significant risk factor of Modic changes. Modic change occurred at a higher frequency in AIS patients than CTR individuals, with lower function and worse ODI scores. LEVEL OF EVIDENCE: 4.

In daily practice, when CT or MRI does not show a pathological lesion in a patient with persistent abnormal neurological signs, it is important to obtain imaging studies of the spine in dynamic position.