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Study Design: A retrospective observational study was performed. Purpose: We investigated the relationships between skeletal muscle mass, bone mineral density (BMD), and trabecular bone score (TBS) in patients with osteoporotic vertebral compression fractures (VCFs). Overview of Literature: The TBS has attracted attention as a measurement of trabecular bone microarchitecture. It is derived from data obtained using dual-energy X-ray absorptiometry (DXA) and is a reported indicator of VCFs, and its addition to the Fracture Risk Assessment Tool increases the accuracy of fracture prediction. Methods: BMD, skeletal muscle mass, and TBS were measured in 142 patients who visited Shimoshizu National Hospital from April to August 2019. Patients were divided into a VCF group and a non-VCF group. Whole-body DXA scans were performed to analyze body composition, including appendicular skeletal muscle mass index (SMI; lean mass [kg]/height [m2]) and BMD. The diagnostic criteria for sarcopenia was an appendicular SMI <5.46 kg/m2. A logistic regression analysis was conducted to identify the risk factors for VCFs. Results: The significant (p<0.05) findings (VCF group vs. non-VCF group, respectively) included age (79 vs. 70 years), femoral BMD (0.50 vs. 0.58 g/cm2), TBS (1.25 vs. 1.29), and lower limb muscle mass (8.6 vs. 9.9 kg). The VCF group was significantly older and had a lower femur BMD and decreased leg muscle mass than the non-VCF group. Based on the multiple logistic regression analysis, lower femoral BMD and decreased leg muscle mass were identified as risk factors for vertebral fracture independent of age, but the TBS was not. Conclusions: Patients with VCFs had low BMD, a low TBS, and low skeletal muscle mass. Lower femoral BMD and decreased leg muscle mass were identified as risk factors for VCFs independent of age, whereas the TBS was not identified as a risk factor for VCFs.

Introduction: Ceramic-on-ceramic (COC) total hip arthroplasty (THA) was developed to reduce wear debris, and consequently the occurrence of osteolysis and aseptic loosening. The purpose of the present study was to determine the incidence and natural history of noise including squeaking after COC THA, and to clarify whether clinical outcomes and any demographic and implant-related factors are associated with noise from these ceramic bearings.Methods: This was a retrospective observational study of 137 primary COC THAs between 2004 and 2009 at our institute. The Mean follow-up was for 10.5 years. All patients were followed up with an office visit to obtain information regarding noise, pain, and function. The correlations between the noise, and patient demographic, radiographic, and implant-related factors were evaluated.Results: Noise developed in 30 hips (21.9%), specifically squeaking in 2 (1.5%) of the 137 hips during the followup period. Noise including squeaking was not associated with pain or functional outcomes. There was significant correlation between noise and cup anteversion, in that cup anteversion of patients with noise was smaller than that in those without noise. No significant correlation was found between noise and any other patient demographic including age, sex, height, body weight, or body mass index. Kaplan Meier survivorship analysis with revision for any reason and an aseptic loosening of either component as the end point, revealed a cumulative survival rate at 10 years of 98.4% and 99.1% respectively.Conclusion: The long-term clinical and radiographic outcome of cementless COC THA is excellent, but we should be vigilant for noise from COC bearings.

Abstract Systemic lupus erythematosus (SLE), an autoimmune disorder, has been associated with nearly 100 susceptibility loci^1-8. Nevertheless, these loci only partially explain SLE heritability and provide limited biological insight. We report the largest study of SLE in East Asians (13,377 cases and 194,993 controls), identifying 233 association signals within 113 (46 novel) genetic loci. We detect six new lead missense variants and prioritize ten most likely putative causal variants, one of which we demonstrate exhibits allele-specific regulatory effect on ACAP1 in vitro. We suggest 677 effector genes with potential for drug repurposing, and provide evidence that two distinct association signals at a single locus act on different genes (NCF2 and SMG7). We demonstrate that SLE-risk variants overlap with cell-specific active regulatory elements, notably EBNA2-mediated super-enhancers in Epstein-Barr Virus-transformed B cells, and implicate the role for non-immune cells in SLE biology. These findings shed light on genetic and biological understandings of SLE.

INTRODUCTION: Little is known about the association between well-fixed polished tapered cemented stems (PTCS) implanted by the line-to-line technique and changes of stem migration, or the change of functional anteversion of the femur after total hip arthroplasty (THA). MATERIALS AND METHODS: This retrospective study included 422 two-stage bilateral primary THAs performed using PTCS implanted by the line-to-line technique. CT scans were made on both the target side (first postoperative CT) and on the contralateral side (second postoperative CT) 1 week postoperatively. The mean follow-up was 7.8 months. CT data for each scan were transferred to 3D template software (Zed hip, Lexi, Japan). The postoperative changes of anatomical stem anteversion (ASA), functional femoral anteversion (FFA), and stem subsidence were evaluated. RESULTS: A total of 20 THAs with CT scans were available on 3D template software. The ASA and the FFA had migrated - 0.68° ± 0.62° and - 5.5° ± 9.7°, respectively, over the follow-up period. A significant positive correlation was observed between the change of subsidence and ASA (r2 = 0.34, p = 0.007), between the FFA on the second postoperative CT and ASA on the first postoperative CT (r2 = 0.26, p = 0.02) and between the FFA on the second postoperative CT and FFA on the first postoperative CT (r2 = 0.52, p = 0.0003). CONCLUSION: This study indicates that the change in axial rotation of a PTCS implanted by the line-to-line technique was less than that reported by other studies and the preoperative external rotation contracture was substantially improved after THA.

We sought to assess the utility of simultaneous apparent T2 mapping and neurography with the nerve-sheath signal increased by inked rest-tissue rapid acquisition of relaxation-enhancement imaging (SHINKEI-Quant) for the quantitative evaluation of compressed nerves in patients with lumbar radiculopathy. Thirty-two patients with lumbar radiculopathy and 5 healthy subjects underwent simultaneous apparent T2 mapping and neurography with SHINKEI-Quant. Regions of interest (ROIs) were placed in the lumbar dorsal root ganglia (DRG) and the spinal nerves distal to the lumbar nerves bilaterally at L4-S1. The T2 relaxation times were measured on the affected and unaffected sides. The T2 ratio was calculated as the affected side/unaffected side. Pearson correlation coefficients were calculated to determine the correlation between the T2 relaxation times or T2 ratio and clinical symptoms. An ROC curve was used to examine the diagnostic accuracy and threshold of the T2 relaxation times and T2 ratio. We observed no significant differences in the T2 relaxation times between the nerve roots on the left and right at each spinal level in healthy subjects. In patients, lumbar neurography revealed swelling of the involved nerve, and prolonged T2 relaxation times compared with that of the contralateral nerve. The T2 ratio correlated with leg pain. The ROC analysis revealed that the T2 relaxation time threshold was 127 ms and the T2 ratio threshold was 1.07. To our knowledge, this is the first study to show the utility of SHINKEI-Quant for the quantitative evaluation of lumbar radiculopathy.

AO/OTA type 31-A1.2 intertrochanteric femoral fractures generally are considered stable intertrochanteric fractures. We report a case of an unstable AO/OTA type 31-A1.2 intertrochanteric femoral fracture. Primary internal fixation was performed with a long cephalomedullary nail taking instability into account. Postoperative X-rays showed an acceptable reduction with a slight fracture gap in extension on the lateral trochanteric side. However, additional salvage surgery was required because the long cephalomedullary nail broke as a result of the instability caused by non-union and varus deformity of the proximal femur. More attention should be directed to strategies of primary internal fixation including choice of fixation instrumentation in terms of mechanical stability because this type of fracture can be remarkably unstable despite radiographic diagnosis of a usually stable AO/OTA classification type 31-A1.2 fracture.

OBJECTIVE: Laminoplasty is an effective procedure for treating cervical spondylotic myelopathy. We conduct myovascular preserving open-door laminoplasty (MPLP) in combination with a laminoplasty plate to improve the stability of the enlarged lamina. We compare the details of the MPLP technique with conventional open-door laminoplasty. METHODS: We compared 25 cases of MPLP (mean age = 70.5, mean follow-up period = 19 months) with 15 controls who received conventional open-door laminoplasty using hydroxyapatite spacers (mean age = 74, mean follow-up period = 53 months). Regarding surgical outcomes, blood loss, operative time, Japanese Orthopaedic Association score, and postoperative visual analog score for neck pain were measured. Regarding image analysis, preoperative and postoperative range of motion (ROM), C2-7 angle, implant back out, hinge bone fusion time, presence or absence of hinge bone union failure, and posterior neck fat infiltration rate were evaluated. RESULTS: Operative time was significantly shorter for MPLP, and postoperative neck pain was significantly decreased. In image evaluation, %ROM was significantly increased in MPLP, but no difference in C2-7 angle existed between the 2 groups. Implant back out was not recognized in either group. In MPLP, the hinge union period was significantly shortened, and the postoperative fat infiltration rate was significantly decreased. CONCLUSIONS: We were able to reduce neck pain after surgery by an approach entailing longitudinal splitting of the spinous processes. We were able to ensure shorter operation times due to cervical plates and better hinge bone fusion times due to initial stability. LEVEL OF EVIDENCE: 4.

Objectives: To document the anatomical variation of the lateral femoral cutaneous nerve (LFCN) at the proximal aspect of the thigh and to determine its susceptibility to injury during total hip arthroplasty via a direct anterior approach (DAA).Methods: We obtained 64 thighs from formalin-preserved cadavers of 45 Japanese individuals. LFCN was identified at the level of the inguinal ligament. All nerve branches of the LFCN were carefully traced distally in the subcutaneous tissue. The branching pattern and distribution at the proximal aspect of the thigh were described. A safe zone to avoid LFCN injury in DAA was estimated for the skin incision.Results: The branching pattern of LFCN was highly varied. There were 37% of the anterior type, characterized by a thicker anterior branch, which coursed along the medial border of the tensor fascia lata (TFL) muscle with thinner branches. There were 63% of the posterior type, characterized by posterior branches thicker than or equal to the anterior branch. In 27 of 64 thighs (42%), the LFCN crossed the skin incision along the midline of the TFL muscle.Conclusion: LFCN showed anatomical variation of anterior and posterior branches and 42% were in danger of injury during DAA.

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.

Proximal femoral fractures are common in elderly osteoporosis patients; however, its prevalence is clinically rare in hip fracture patients with hip osteoarthritis (OA). This study aimed to evaluate bone strength of the proximal femur with or without hip OA and proximal femoral fracture risk using computed tomography (CT)-based finite element analysis (FEA). A retrospective analysis was done on CT data of 20 patients who underwent total hip arthroplasty for unilateral hip OA. Furthermore, the fracture load between OA and contralateral sides was compared and the association between fracture load and risk factor was analyzed. The fracture load was significantly higher in the OA side than that in the contralateral side (3819.5 ± 1557.8 N vs. 3224.5 ± 943.7 N, respectively; P = 0.0405). There was no significant difference in fracture load between OA and the contralateral side in Kellgren-Lawrence (KL)-3 and KL-4 grade, but the KL-4 fracture load tends to be high (P = 0.2461 and P = 0.0527, respectively). Moreover, there was no significant association between fracture load and OA severity or age. The study findings may assist in predicting bone strength and proximal femur fracture risk. The results of this FEA study indicate the bone strength of the proximal femur was affected by the severity of the osteoarthritis.

Objectives: The goals of this study were to elucidate the distribution of multifocal osteonecrosis associated with glucocorticoid therapy using magnetic resonance imaging (MRI) and to establish a MRI screening method.Methods: Between 1986 and 2018, 107 patients underwent MRI screening of their hips, knees, shoulders and ankle joints (856 joints in total) after systemic glucocorticoid therapy.Results: Osteonecrosis was observed in hip (68%), knee (44%), ankle (17%) and shoulder (15%) joints. Patients with bilateral osteonecrosis in their hips were likely to have bilateral osteonecrosis in their knees, whereas patients without osteonecrosis in both hips were unlikely to have osteonecrosis in both knees (p = .0299). Osteonecrosis was never evident in the ankle or shoulder joints when a patient did not have osteonecrosis in both hip and knee joints.Conclusion: In this study, MRI - as a screening method for multifocal osteonecrosis associated with glucocorticoid therapy - showed the sites affected first are hips and knees followed by ankles and shoulders. If osteonecrosis is absent in hip and knee joints, further screening of the ankles and shoulders is unnecessary. Any osteonecrosis observed in the hip and/or the knee joints warrants a second MRI screening of the ankles and shoulders.

BACKGROUND: As Japan has an aging population, elderly patients with multiple complicating comorbidities have increased in number. The purpose of the present study was to examine the 90-day mortality and reoperation rate after emergency amputation of the lower limbs and to clarify patient characteristics and preoperative comorbidities that are risk factors for reoperations. METHODS: This retrospective case study was conducted between January 2005 and December 2017. Ninety-one patients with 108 limbs who had undergone emergency amputation of the lower limbs were included in this study. Baseline data, medical comorbidities, surgical procedures and laboratory data including C-reactive protein (CRP), white blood cells (WBC) and hemoglobin A1c (HbA1c) were evaluated. Outcome measurements were mortality, reoperation rate, and factors associated with reoperation in 90 days and any complication after amputation of the lower limbs. RESULTS: The patients (male/female ratio = 64/27) had a mean age of 64.9 years, a mean WBC count of 16,747/μL, a mean CRP value of 15.6 mg/dL, and a mean HbA1c value of 7.5%. The 90-day mortality rate in the study population was 12.1%. The 90-day reoperation rate was 35.2% (32/91) patients with 32.4% (35/108) limbs. The factor significantly associated with reoperation in 90 days was peripheral arterial disease (PAD) (p = 0.022, HR = 2.75), identified with Cox proportional hazards regression analysis. A total of 41.8% (38/91) patients with 40.7% (44/108) limbs experienced postoperative wound complications. The overall rate of medical complications was 18.7% (17/91) patients with 16.7% (18/108) limbs. CONCLUSIONS: This study indicates that the 90-day mortality and reoperation rates after emergency amputation of the lower limbs were high. Furthermore, PAD influences the rate of reoperation in 90 days. However, there was no association between laboratory results or diabetes mellitus and reoperation. These findings will have important implications for the treatment of lower leg amputation and prevention of reoperation.

There is no imaging modality to quantitatively evaluate compressed cervical nerve roots in cervical radiculopathy. Here we sought to evaluate the usefulness of simultaneous apparent T2 mapping and neurography with nerve-sheath signal increased with inked rest-tissue rapid acquisition of relaxation-enhancement imaging (SHINKEI-Quant) to evaluate compressed nerves quantitatively in patients with cervical radiculopathy due to cervical disc hernia before microendoscopic surgery. One patient with cervical radiculopathy due to cervical disc hernia before microendoscopic surgery and 5 healthy subjects underwent simultaneous apparent T2 mapping and neurography with SHINKEI-Quant. The patient was a 49-year-old man with severe right upper arm pain and numbness. Based on MRI images, we suspected right C7 radiculopathy due to C6-7 cervical disc hernia. The T2 relaxation times of the cervical dorsal root ganglia of the brachial plexus bilaterally at C5-C8 were measured. We observed no significant differences in T2 relaxation times between the nerve roots on the left and right at each spinal level with values in healthy subjects. In our patient, neurography revealed swelling of the right C7 nerve, and a prolonged T2 relaxation time compared with that of the contralateral, unaffected C7 nerve. We performed microendoscopic surgery and the symptoms improved. We were able to evaluate the injured nerve root quantitatively in a patient with cervical radiculopathy using the SHINKEI-Quant technique, being the first study to our knowledge to show the usefulness of this technique to evaluate cervical radiculopathy quantitatively before microendoscopic surgery.

BACKGROUND: The Association Research Circulation Osseous (ARCO) presents the 2019 revised staging system of osteonecrosis of the femoral head (ONFH) based on the 1994 ARCO classification. METHODS: In October 2018, ARCO established a task force to revise the staging system of ONFH. The task force involved 29 experts who used a web-based survey for international collaboration. Content validity ratios for each answer were calculated to identify the levels of agreement. For the rating queries, a consensus was defined when more than 70% of the panel members scored a 4 or 5 rating on a 5-point scale. RESULTS: Response rates were 93.1%-100%, and through the 4-round Delphi study, the 1994 ARCO classification for ONFH was successfully revised. The final consensus resulted in the following 4-staged system: stage I-X-ray is normal, but either magnetic resonance imaging or bone scan is positive; stage II-X-ray is abnormal (subtle signs of osteosclerosis, focal osteoporosis, or cystic change in the femoral head) but without any evidence of subchondral fracture, fracture in the necrotic portion, or flattening of the femoral head; stage III-fracture in the subchondral or necrotic zone as seen on X-ray or computed tomography scans. This stage is further divided into stage IIIA (early, femoral head depression ≤2 mm) and stage IIIB (late, femoral head depression >2 mm); and stage IV-X-ray evidence of osteoarthritis with accompanying joint space narrowing, acetabular changes, and/or joint destruction. This revised staging system does not incorporate the previous subclassification or quantitation parameters, but the panels agreed on the future development of a separate grading system for predicting disease progression. CONCLUSION: A staging system has been developed to revise the 1994 ARCO classification for ONFH by an expert panel-based Delphi survey. ARCO approved and recommends this revised system as a universal staging of ONFH.

We investigated the efficacy of duloxetine on hyperalgesia, histopathological and radiographic findings, pain-related sensory innervation of dorsal-root ganglia (DRG), and spinal changes in a rat model of induced hip osteoarthritis (OA). The right hip joints of male Sprague-Dawley rats (n = 6 rats/group) in the Sham group were injected with 25 μl of sterile saline and 25 μl of sterile saline with 2 mg of monosodium iodoacetate (MIA) were injected to the MIA + Vehicle and MIA + Duloxetine groups. We injected duloxetine 20 mg/kg intraperitoneally in the MIA + Duloxetine group 28 days after injection, whereas rats in the MIA + Vehicle group were injected with 0.5 ml of 20% dimethyl sulfoxide. We assessed hyperalgesia, histopathological changes, immunoreactive (-ir) neurons for calcitonin gene-related peptide and activating transcription factor 3 in DRG, and immunoreactive neurons for ionized-calcium-binding adaptor molecule 1 (Iba1) in the dorsal horn of the spinal cord. MIA administration into the hip joint let to mechanical hyperalgesia of the ipsilateral hind paw (p < 0.05). A single injection of duloxetine significantly attenuated it in induced hip OA (p < 0.05) and suppressed the number of Iba1-ir microglia of the ipsilateral dorsal horn (p < 0.05). These results suggest that a single injection of duloxetine suppressed mechanical hyperalgesia and may influence the expression of Iba1 in the microglia of the ipsilateral dorsal horn in the MIA-induced hip OA. This finding implies the inhibitory effects of duloxetine against neuropathic pain, which may lead to a change of microglial activities. © 2019 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 38:422-430, 2020.

BACKGROUND: Femoral nerve palsy is a serious neurological complication following total hip arthroplasty (THA) via a direct anterior approach. One hypothesis is that the nerve injury is caused by malpositioning of retractors over the anterior wall of the acetabulum. The purpose of this cadaveric study was to clarify the anatomical features of the femoral nerve around the anterior acetabular rim and the potential risk of nerve injury during a direct anterior approach to THA. METHODS: We dissected 84 cadaveric hips from 44 formalin-embalmed cadavers. When the cadavers were supine, the iliopsoas muscle and the femoral nerve were exposed and the anterior joint capsule and labrum were resected. The measurement points were determined along the acetabular rim every 30°, and a reference line was drawn from the anterior superior iliac spine to the center of the acetabulum, with the intersection of the rim at 0°. The minimum distance to the femoral nerve margin was measured from 0° to 150° (6 points). Other anatomical structures were measured to determine their association with the distance of the shortest measurement points. RESULTS: The mean minimum distances to the femoral nerve were 33.2 mm at 0°, 24.4 mm at 30°, 18.4 mm at 60°, 16.6 mm at 90°, 17.9 mm at 120°, and 23.2 mm at 150°, showing that the distance at 90° was the shortest (p < 0.001). The thickness of the iliopsoas muscle and the femoral length were positively associated with the distance to the femoral nerve at 90°. CONCLUSIONS: In this cadaveric study, the femoral nerve was within 16.6 to 33.2 mm of the acetabular rim at points from 0° to 150° of a line drawn from the anterior superior iliac spine. The nerve was closest to the rim at 90°, indicating that this is an area of high risk during retractor placement. CLINICAL RELEVANCE: Retractor placement at 90° to the anterior acetabular rim should be avoided to reduce the risk of femoral nerve injury.

An acetabular component of total hip arthroplasty that protrudes into the pelvis carries a risk of injury to the iliac blood vessels during removal of the implant. We report three cases of intrapelvic migration of an acetabular component in contact with the iliac vessels. Preoperative computed tomography angiography in all cases revealed that the external /or internal iliac vessels were displaced superiomedially due to compression by the migrated cup. The implants were removed safely using a conventional hip approach in combination with release of vessels via a retroperitoneal approach in two cases, and via temporal intra-aortic balloon occlusion in one case. One of the two patients treated with a retroperitoneal approach underwent acetabular reconstruction in a consecutive surgery in a supine position through a direct anterior approach, and the other underwent reconstruction through a direct lateral approach after a postural change. For the patient who underwent intra-aortic balloon occlusion, we performed resection arthroplasty to allow a less invasive treatment. No marked intraoperative bleeding caused by injury to iliac vessels occurred in any patient, although one case required blood transfusion for oozing. These cases show that dissection of the iliac vessels via a retroperitoneal approach is safe with minimum morbidity during handling of the migrated acetabular components. A direct anterior approach can be used for acetabular revision of the protruded components without patient repositioning by combining this procedure with a retroperitoneal approach. Intra-aortic balloon occlusion is an alternative for protruded components in a case with a risk of vessel injury during dissection.

Introduction: Despite preserving lumbar disc mobility, spinal sagittal, and/or coronal alignment might ultimately impede surgical success. The purpose of this study was to elucidate the effects of spinal alignment on lumbar disc degeneration after 5 or more years in adolescent idiopathic scoliosis (AIS) patients who underwent spinal fusion. Methods: Subjects were 49 AIS patients who underwent posterior spinal fusion without lumbar curve fusion. The inclusion criteria were the following: 1) Lenke type 1A, 1B, 2A or 2B, 2) age 10 to 19 years at the time of operation, and 3) minimum 5-year follow-up. The exclusion criteria were the following: 1) diagnosed as other than AIS, 2) history of lumbar disc herniation and spondylolysis, 3) subsequent surgery, and 4) history of surgery before AIS surgery. Nineteen patients agreed to participate in this research. X-rays, lumbar MRI, and questionnaires were evaluated. Disc degeneration in non-fused segments was defined as Pfirrmann grade 3 or higher. Patients with disc degenerations at the final observation (DD[+] group) were compared to those without disc degenerations (DD[-] group). Results: There were no significant differences in the preoperative or postoperative 1-week X-ray parameters between both groups. The lumbar curve was significantly larger in the DD[+] group compared with the DD[-] group at the final observation (DD[+]: 16.8 degrees, DD[-]: 10.4 degrees, p = 0.035). The sagittal vertical axis (SVA) was significantly larger in the DD[+] group compared with the DD[-] group at the final observation (DD[+]: -4.4 mm, DD[-]: -34.3 mm, p = 0.006). SRS-22 function, self-image, and satisfaction scores were lower in the DD [+] group compared with the DD[-] group at the final observation. Conclusions: The patients with DD had significantly larger lumbar curve and SVA with lower SRS-22 function, self-image, and satisfaction scores at the final observation. Even though the non-fused segments were preserved, spinal alignments of non-fused lumbar curve affect the DDs.

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.

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.

BACKGROUND: To investigate dural sac enlargements and spinal alignments in patients who underwent indirect decompression with interspinous spacers. METHODS: The subjects were 20 patients who underwent indirect decompression using an interspinous spacer (X-STOP) without laminectomy. Of these 20 patients, 1 patient underwent implant removal surgery 1 month after X-STOP surgery and two patients dropped out. Ultimately, 17 patients were included in this study. MRI and X-ray images were investigated before surgery, 1 week after surgery, 3 months after surgery, and 2 years after surgery. RESULTS: On MRI, the mean cross-sectional areas of the dural sac were 52.7 mm2 before surgery, 73.2 mm2 1 week after surgery, 62.4 mm2 3 months after surgery, and 58.3 mm2 2 years after surgery. There was a significant 37% increase at 1 week postoperatively compared with that before surgery, but there were no significant differences between 3 months postoperatively and 2 years postoperatively. The disc angle in an extension posture was significantly decreased at 1 week after surgery compared with that before surgery, but there were no significant differences between before surgery, 3 months after surgery, and 2 years after surgery. CONCLUSIONS: The interspinous process spacer increased the dural sac area by 37% 1 week after surgery, but the enlargement was not maintained at 3 months or 2 years after surgery. The use of interspinous process spacers produced an enlargement of the dural sac by limiting extension of the stenotic level only. However, its effect diminished 2 years after surgery.

Study Design: A retrospective cohort study. Purpose: This study aims to investigate postoperative shoulder imbalance (PSI) ≥5 years postoperatively in patients who underwent posterior spinal fusion using hooks at the upper instrumented vertebra (UIV) for Lenke type 1 adolescent idiopathic scoliosis (AIS). Overview of Literature: Studies have reported PSI due to excessive correction of the main thoracic curve. Methods: We examined 56 patients with AIS who underwent a posterior spinal fusion with hooks at the UIV from 2004 to 2010. Of these, we enrolled 14 patients who underwent surgery, at least, 5 years ago. X-rays and Scoliosis Research Society-22 (SRS-22) questionnaire were administered. To evaluate the shoulder balance, T1 vertebral tilt angle (T1 tilt), clavicle angle, and radiographic shoulder height (RSH) were measured. PSI was considered as the absolute value of the postoperative RSH being ≥20 mm. Based on radiographs obtained immediately postoperatively, we divided patients into two groups as follows: the balanced group (absolute value of RSH <20 mm) and imbalanced group (absolute value of RSH ≥20 mm). Results: The frequency of PSI was 28.6% immediately postoperatively, 0% 2 years postoperatively, and 7.1% at the last follow-up. In the balanced group, PSI did not occur even at 2 years postoperatively or at the last follow-up. In the imbalanced group, PSI was improved in all patients 2 years postoperatively and all patients, except one patient, at the last follow-up. No significant differences were noted in the frequency of distal adding-on at 2 years postoperatively or the last follow-up between the balanced group and the imbalanced group. We observed moderate negative correlations between the absolute value of T1 tilt and the SRS-22 pain and satisfaction at the last follow-up. Conclusions: Hooks at the UIV could adjust the shoulder balance to avoid long-term PSI in patients with AIS.

BACKGROUND: Accurate evaluation of the postoperative position of total knee arthroplasty (TKA) components is crucial in the analysis of the association of alignments with clinical outcomes. The aim of this study was to investigate the reliability of measurements of component positions after TKA using three-dimensional computed tomography (3D-CT) reconstruction. METHODS: Two independent orthopedic surgeons (an attending surgeon and a fellow) examined 30 knees after primary TKA. The coronal, sagittal, and rotational positions of the femoral and tibial components were measured twice at an interval of six weeks on 3D-CT images reconstructed using ZedKnee software. Mean intra- and interobserver differences of measured angles were calculated, and the intra- and interobserver reliability was determined using intraclass correlation coefficients (ICCs), with agreement assessed by Bland-Altman analysis. RESULTS: The mean intraobserver difference between alignment measurements for femoral and tibial components was <2° (range 0.23-1.17°) and the mean interobserver difference was <1° (range 0.22-0.97°). The intra- and interobserver ICCs were >0.8 for all component positions. The only systematic bias found in the intra- and interobserver agreements occurred for the sagittal position of the femoral component. CONCLUSION: Three-dimensional-CT measurements of component positions after TKA showed good intra- and interobserver reliability for the femoral and tibial components in coronal, sagittal and rotational positions. The intra- and interobserver agreements were favorable for all but the sagittal position of the femur. These results suggest that 3D-CT can be used to evaluate the alignment of all TKA components except for the sagittal position of the femur.

Objective: The aim was to compare the fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of the sciatic and femoral nerves in patients with unilateral osteoarthritis of the hip (OA) and osteonecrosis of the femoral head (ONFH) using diffusion tensor imaging (DTI) and to investigate the mechanism of hip pain. Methods: Forty-four patients (22 OA and 22 ONFH) underwent DTI of the sciatic and femoral nerves at the level of the hip joint and the S1 roots to visualize the tractography and quantify the FA and ADC values. Results: The tractography of the femoral and the sciatic nerves on the affected side with OA and ONFH were similar to those on the normal side. The mean FA values of the sciatic and femoral nerves, and the S1 roots were 0.542, 0.551, and 0.316 with OA, 0.568, 0.560, and 0.318 with ONFH on the affected side, and 0.559, 0.560, and 0.315 on the normal side, respectively, and did not show significant differences. The FA values of the sciatic nerve on the affected side with OA decreased with longer pain duration. Conclusion: The FA and ADC values of the sciatic and femoral nerves in patients with unilateral OA and ONFH showed no significant differences between the affected and normal sides.

PURPOSE: We investigated the involvement of sarcopenia in middle-aged and elderly women with degenerative lumbar scoliosis (DLS). METHODS: A total of 971 women (mean age 70.4 years) were included in our study. These included 87 cases of DLS (mean 73.8 years) and 884 controls (69.8). Lumbar and femur BMD was measured for all participants using dual-energy X-ray absorptiometry. We used a bioelectrical impedance analyzer to analyze body composition, including appendicular skeletal muscle mass index (SMI; appendicular lean mass (kg)/(height (m))2. We determined bone density and skeletal muscle mass in both groups and determined the prevalence of sarcopenia. We examined the correlation between bone density and appendicular muscle mass in both groups. We also examined factors related to scoliosis using logistic regression analysis. RESULTS: The DLS group showed significantly higher lumbar BMD, lower femur BMD, lower lean mass arm, and lower lean mass leg, and lower lean mass trunk (p < 0.05). Sarcopenia prevalence (SMI < 5.75) was 59.8% in DLS subjects and 42.8% in controls, revealing a high prevalence in DLS (p < 0.05). In both groups, lumbar and femur BMD were positively correlated with appendicular muscle mass. By logistic regression analysis, trunk muscle mass was detected as a risk factor for DLS independent of age (p < 0.05). CONCLUSIONS: In middle-aged and elderly women, prevalence of sarcopenia was 59.8% in DLS cases and 42.8% in controls, which revealed a high prevalence in DLS. A decrease in trunk muscle was a significant risk factor for DLS that was independent of age. These slides can be retrieved under Electronic Supplementary Material.

BACKGROUND CONTEXT: Platelet-rich plasma (PRP) accelerates bone union in vivo in a rodent model of spinal fusion surgery. However, PRP's effect on bone union after spinal surgery remains unclear. PURPOSE: The objective of this study was to evaluate the efficacy of PRP after posterolateral lumbar fusion (PLF) surgery. STUDY DESIGN/SETTING: Single-center prospective randomized controlled clinical trial with 2-year follow-up. PATIENT SAMPLE: The patient sample included a total 62 patients (31 patients in the PRP group or 31 patients in the control group). OUTCOME MEASURES: The outcome measures included the bone fusion rate, the area of bone fusion mass, the duration of bone fusion, and the clinical score using the visual analog scale (VAS). MATERIALS AND METHODS: We randomized 62 patients who underwent one- or two-level instrumented PLF for lumbar degenerative spondylosis with instability to either the PRP (31 patients) or the control (31 patients) groups. Platelet-rich plasma-treated patients underwent surgery using an autograft bone chip (local bone), and PRP was prepared from patient blood samples immediately before surgery; patients from the control group underwent PLF without PRP treatment. We assessed platelet counts and growth factor concentrations in PRP prepared immediately before surgery. The duration of bone union, the postoperative bone fusion rate, and the area of fusion mass were assessed using plain radiography every 3 months after surgery and by computed tomography at 12 or 24 months. The duration of bone fusion and the clinical scores for low back pain, leg pain, and leg numbness before and 3, 6, 12, and 24 months after surgery were evaluated using VAS. RESULTS: Data from 50 patients with complete data were included. The bone union rate at the final follow-up was significantly higher in the PRP group (94%) than in the control group (74%) (p=.002). The area of fusion mass was significantly higher in the PRP group (572 mm2) than in the control group (367 mm2) (p=.02). The mean period necessary for union was 7.8 months in the PRP group and 9.8 months in the control group (p=.013). In the PRP, the platelet count was 7.7 times higher and the growth factor concentrations were 50 times higher than those found in plasma (p<.05). There was no significant difference in low back pain, leg pain, and leg numbness in either group at any time evaluated (p>.05). CONCLUSIONS: Patients treated with PRP showed a higher fusion rate, greater fusion mass, and more rapid bone union after spinal fusion surgery than patients not treated with PRP.

OBJECTIVEThe purpose of this study was to determine the relationship between vertebral bodies, psoas major morphology, and the course of lumbar nerve tracts using diffusion tensor imaging (DTI) before lateral interbody fusion (LIF) to treat spinal deformities.METHODSDTI findings in a group of 12 patients (all women, mean age 74.3 years) with degenerative lumbar scoliosis (DLS) were compared with those obtained in a matched control group of 10 patients (all women, mean age 69.8 years) with low-back pain but without scoliosis. A T2-weighted sagittal view was fused to tractography from L3 to L5 and separated into 6 zones (zone A, zones 1-4, and zone P) comprising equal quarters of the anteroposterior diameters, and anterior and posterior to the vertebral body, to determine the distribution of nerves at various intervertebral levels (L3-4, L4-5, and L5-S1). To determine psoas morphology, the authors examined images for a rising psoas sign at the level of L4-5, and the ratio of the anteroposterior diameter (AP) to the lateral diameter (lat), or AP/lat ratio, was calculated. They assessed the relationship between apical vertebrae, psoas major morphology, and the course of nerve tracts.RESULTSAlthough only 30% of patients in the control group showed a rising psoas sign, it was present in 100% of those in the DLS group. The psoas major was significantly extended on the concave side (AP/lat ratio: 2.1 concave side, 1.2 convex side). In 75% of patients in the DLS group, the apex of the curve was at L2 or higher (upper apex) and the psoas major was extended on the concave side. In the remaining 25%, the apex was at L3 or lower (lower apex) and the psoas major was extended on the convex side. Significant anterior shifts of lumbar nerves compared with controls were noted at each intervertebral level in patients with DLS. Nerves on the extended side of the psoas major were significantly shifted anteriorly. Nerve pathways on the convex side of the scoliotic curve were shifted posteriorly.CONCLUSIONSA significant anterior shift of lumbar nerves was noted at all intervertebral levels in patients with DLS in comparison with findings in controls. On the convex side, the nerves showed a posterior shift. In LIF, a convex approach is relatively safer than an approach from the concave side. Lumbar nerve course tracking with DTI is useful for assessing patients with DLS before LIF.

INTRODUCTION: Stress fracture is generally a result of cumulative and repetitive stress in athletes, which accelerates the normal remodeling process of bones, and the most frequently involved areas are the tibia and metatarsal bones. Therefore, stress fractures of the midshaft of the clavicle are very rare. PRESENTATION OF CASE: A 58-year-old female was admitted to our hospital because of pain in the middle of the right clavicle. Based on laboratory and radiographic inspection, it was concluded that the stress fracture of the midshaft of the clavicle in this case was caused by sternocostoclavicular hyperostosis (SCCH). Because the clavicular fracture had no displacement or callus formation, conservative treatment with a clavicle band was undertaken. Shoulder function at the final follow-up visit was satisfactory. DISCUSSION: SCCH is a rare chronic inflammatory disorder of the axial skeleton and ossifying diathesis associated with a predominantly osteogenic response. Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome and ankylosing spondylitis (AS) should be considered in the differential diagnosis of SCCH. If a patient with this type of fracture has no history of traumatic injury or sports activity, the differential diagnosis might be very difficult. CONCLUSION: We report the case of a female who had a stress fracture of the midshaft of the clavicle associated with SCCH in SAPHO or AS. Although the patient was treated conservatively, and the shoulder function was satisfactory at the final follow-up visit, re-fracture may occur in the future.

Introduction: The purpose of this study is to investigate thoracic deformity correction and pulmonary function changes in patients with adolescent idiopathic scoliosis (AIS) five years or more after undergoing posterior spinal fusion with thoracoplasty for correction of a thoracic deformity. Methods: Subjects were 57 patients with AIS who underwent posterior spinal fusion between 2004 and 2010. 24 patients who had undergone thoracoplasty at least five years earlier agreed to participate in this research. X-rays, pulmonary function tests, and thoracic cage computed tomography (CT) were performed, and the Scoliosis Research Society Outcomes Questionnaire (SRS-22) was administered. CT axial images were used at the apex of the main thoracic (MT) curve. Apical vertebral rotation was evaluated using rotation angle to the sagittal plane (RAsag). Thoracic deformities were evaluated using the rib hump index (RHi) and the posterior hemithoracic symmetry ratio (PHSr). Results: There were no significant differences between the preoperative and the final observation forced vital capacity (FVC) or the preoperative and the final observation %FVC. The forced expiratory volume in 1 s (FEV1) and %FEV1 were significantly improved at the final observation: FEV1 (preoperative: 1.88 L, final observation: 2.05 L, p = 0.045) and %FEV1 (preoperative: 57.1%, final observation: 66.2%, p = 0.001). FEV1/FVC was also significantly improved at the final observation (preoperative: 83.0%, final observation: 86.4%, p = 0.019). The peak expiratory flow (PEF) was significantly improved at the final observation (preoperative: 3.67 L/s, final observation: 4.38 L/s, p = 0.029). On the CT assessment for thoracic deformities, there were no significant changes in RAsag or RHi. PHSr was significantly increased at the final observation compared with the preoperative period. Conclusions: With posterior spinal fusion in combination with thoracoplasty for AIS, although the correction of deformities was limited, the pulmonary function testing demonstrated the preservation of vital capacity (VC) and improvements in the forced expiratory volume in 1 s and expiratory flow.

Introduction: To investigate the risk of epidural hematoma after spinous process-splitting laminectomy (SPSL). Methods: A total of 137 cases (mean age, 72.4 years; 68 men) of SPSL were included. Of these, there were instances (3.7%; mean age, 70.5 years; all male) of postoperative development of new neurologic deficit due to epidural hematoma requiring reoperation. The 133 subjects (72.5 years; 64 men) with normal postoperative course were used as controls, and comparisons were made between both groups using chi-squared and Student's t-tests. Regarding our investigation of risk factors for epidural hematoma, logistic regression was conducted with presence or absence of hematoma as our primary outcome variable, and age, gender, disease duration, number of laminectomies, which levels were decompressed, blood loss, length of case, drain output, coagulopathy, and whether or not there was an intraoperative dural tear were our explanatory variables. Results: All cases of hematoma were single-level laminectomies; there was one case of T9-10 and 3 cases of L2-3. In our direct comparison of both groups (hematoma versus control), the proportion of men was significantly higher in the hematoma group (100% versus 48%, p < 0.05); levels decompressed were also significantly higher (p < 0.05) in the hematoma group, and drain outputs were significantly lower (113 mL versus 234 mL, p < 0.05). From our logistic regression analysis, the levels were significantly higher (χ2 = 15, p = 0.0001) and the drain outputs were smaller (χ2 = 4.6, p = 0.03) in the hematoma group. Conclusions: Single-level decompression higher than the L2-3 level and reduced drain output were risk factors for spinal epidural hematoma. With this method of spinous process suturing and reconstruction there is less decompression compared with more conventional methods; therefore, the effect of hematoma may be more pronounced at higher vertebral levels with reduced canal width, and drain failure may also occur with this limited space.

The aim of this study was to investigate the local production of proinflammatory cytokines, pain-related sensory innervation of dorsal-root ganglia (DRG), and spinal changes in a rat model of induced hip osteoarthritis (OA). Seventy-five Sprague-Dawley rats were used, including 25 controls and 50 injected into the right hip joints (sham group, injected with 25 µl of sterile saline: N = 25; and monosodium iodoacetate (MIA) group, injected with 25 µl of sterile saline with 2 mg of MIA: N = 25). We measured the local production of TNF-α, immunoreactive (-ir) neurons for calcitonin gene-related peptide (CGRP), and growth associated protein-43 (GAP-43) in DRG, and immunoreactive neurons for ionized-calcium-binding adaptor molecule-1 (Iba-1) in the dorsal horn of spinal cord, on post-induction days 7, 14, 28, 42, and 56 (N = 5 rats/group/time point). For post-induction days 7-42, the MIA group presented significantly elevated concentrations of TNF-α than the other groups (p < 0.01), and a higher expression of CGRP-ir in FG-labeled DRG neurons than the sham group (p < 0.01). MIA rats also presented significantly more FG-labeled GAP-43-ir DRG neurons than the sham group on post-induction days 28, 42, and 56 (p < 0.05), and a significantly higher number of Iba-1-ir microglia in the ipsilateral dorsal horn than the other groups, on post-induction days 28, 42, and 56. The results suggest that in rat models, pain-related pathologies due to MIA-induced hip OA, originate from inflammation caused by cytokines, which leads to progressive, chronic neuronal damage that may cause neuropathic pain. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2978-2986, 2018.

BACKGROUND: Little is known about how bone cement and American Society of Anesthesiologists (ASA) classification influence the cardiovascular system in elderly patients with femoral-neck fractures treated with cemented hemiarthroplasty. Therefore, we performed a case-control study to investigate these questions and compared the following:≥ASA III with≤ASA II patients who underwent cemented hemiarthroplasty; and cemented with cementless hemiarthroplasty in≥ASA III patients. HYPOTHESIS: ASA classification influences the cardiovascular system during cemented hemiarthroplasty and bone cement influences intraoperative blood pressure [IBP] in patients rated≥ASA III. MATERIALS AND METHODS: This multicenter, prospective study included patients with acute displaced femoral-neck fractures. Baseline data, medical history, anesthesia, FiO2, vasopressor use, femoral component, IBP, SpO2, and complications were evaluated. Of 200 patients, 100 were cemented (mean age, 77±10 years), and 100 were cementless (mean age, 78±9 years). Cemented hemiarthroplasty employed a third-generation technique (plugging, irrigating, drying and filling the canal with cement under pressurization). RESULTS: Systolic blood pressure (SBP) decreased significantly during cementing, versus pre-rasping in≤ASA II patients (from 117.9±24.5 [range, 65-199] to 106.9±20.3 [range, 59-172]; p=0.007), in≥ASA III patients (from 129.5±21.0 [range, 90-169] to 110.4±17.9 [range, 79-157]; p=0.006), and post-stem-insertion, versus pre-rasping in≤ASA II patients (from 117.9±24.5 [range, 65-199] to 103.9±20.7 [range, 53-178]; p=0.0004), and in≥ASA III patients (from 129.5±21.0 [range, 90-169] to 111.2±24.6 [range, 70-156]; p=0.009). In≥ASA III patients, SBP decreased significantly during cementing or rasping, versus pre-rasping in cemented patients (from 129.5±21.0 [range, 90-169] to 110.4±17.9 [range, 79-157]; p=0.006), in cementless patients (from 115.0±17.7 [range, 85-150] to 100.7±15.7 [range, 75-142]; p=0.004), and post-stem-insertion, versus pre-rasping in cemented patients (from 129.5±21.0 [range, 90-169] to 111.2±SD [range]; p=0.009), and in cementless patients (from 115.0±17.7 [range, 85-150] to 89.4±17.5 [range, 58-140]; p<0.0001). There were no lethal complications. CONCLUSIONS: This study indicate a similar hemodynamic change intraoperatively between≤ASA II patients and≥ASA III patients in the cemented group, and between patients with cemented and cementless hemiarthroplasty in the≥ASA III patients. With modern hemiarthroplasty techniques, bone cement might be as safe as cementless techniques in elderly,≥ASA III patients. LEVEL OF EVIDENCE: III, multicenter case-control cohort study.

type:text [要旨] 【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。 [SUMMARY] Purpose. To compare compression and ice treatments in a rat model of muscle injury. Methods. A model of muscle injury was made in 108 eight-week-old Sprague Dawley male rats by dropping a weight onto their right gastrocnemius muscle. We compared compression and ice treatments after the contusion injury with no treatment. We evaluated the injuries using histology andan enzyme-linked immunosorbent assay for tumor necrosis factor α. We used Fluoro-Gold to traceneural afferents from the region of the contusion injury. The proportion of calcitonin gene-related peptide-immunoreactive neurons in all Fluoro-Gold-labeled neurons was determined to evaluate pain. Results. In the compression treatment group, the injured muscle tended to have less hemorrhage and edema at ? 6 h after the injury. Tumor necrosis factor α levels were lower, and the local acutephase in flammatory reaction was milder than in untreated rats. We found less necrosis of muscle tissue on the third day after injury and the replacement of granulation tissue and regeneration of muscle fibers 1 week after the injury. The proportion of calcitonin gene-related peptide-immunoreactive Fluoro-Gold-labeled neurons in total Fluoro-Gold-labeled neurons was significantly lower than in untreated rats. In the ice treatment group, although injured muscle had decreased hemorrhage and edema 6 h after the injury, hemorrhage and edema increased ?18 h after injury. Tumor necrosis factor α levels were transiently increased compared with those in untreated rats（ 3 h and 6 h after contusion）. On the third day after contusion injury, necrosis of muscle was severe. We observed the replacement of granulation tissue and regeneration of muscle fibers 1 week after the injury. The proportion of calcitonin gene-related peptide-immunoreactive Fluoro-Gold-labeled neurons was significantly lower than in untreated rats. Conclusion. In our study, compression may promote muscle tissue repair by preventing hematoma formation during the repair phase and preventing prolonged pain. On the other hand, ice therapy may prevent prolonged pain through pain relief from the stimulation of cold receptors, enabling animals to proceed with an early range of motion exercise, suppressing hypoactivity and promoting muscle tissue repair during the recovery phase. Overall, our current study indicated that there was a difference between compression and ice treatments during the acute and repair phases of muscle injury.

BACKGROUND: The purpose of this cadaveric study was to clarify the proximal limit for the subvastus approach (SVA) in total knee arthroplasty to decrease potential vascular injury. METHODS: Seventy embalmed knees underwent a modified SVA using a 14-cm oblique medial incision. Anatomical features of the descending genicular artery (DGA) were investigated with regard to variation, distance of the vessels from surgical landmarks, and sex differences. RESULTS: The DGA was identified in 62 knees (89%), while it was absent in 8 knees (11%); in the latter, the articular, saphenous, and muscular branches arose separately from the femoral artery. The mean distances from the tibial tuberosity and medial joint line to the origin of the DGA were 15.5 ± 1.6 cm and 12.6 ± 1.6 cm, respectively. Both distances were significantly longer in males than in females (P < .01, respectively). A strong positive correlation was found between the distance from the tibial tuberosity to the origin of the DGA and the distance from the medial joint line to the origin of the DGA (Spearman's correlation coefficient, R2 = 0.72, P < .01). A weak positive correlation was found between the distance from the tibial tuberosity to the origin of the DGA and lower leg length (R2 = 0.13, P < .01). No vascular injuries were observed in this surgical exposure. CONCLUSION: The DGA showed several variations and was absent 11% of the time. An oblique medial incision within 14 cm from the tibial tuberosity followed by arthrotomy is considered a safe zone for the SVA.

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.

PURPOSE: Quality-of-life (QOL) assessments in patients with osteonecrosis of the femoral head (ONFH) have rarely been reported. This multicentre study aimed to elucidate the relationship between disease severity, including necrotic lesion type and radiological staging, and QOL, as well as between patients' characteristics and QOL. METHODS: Two hundred seventy-four patients with ONFH (108 females, 166 males; median age, 46 years) were asked to complete self-assessment QOL questionnaires including the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire, Oxford Hip Score, and SF-12v2. RESULTS: Patients with large necrotic lesion type or collapsed ONFH had low QOL scores. Among patients with non-collapsed lesions, patients with alcohol-associated ONFH had lower QOL scores than those with steroid-associated ONFH, those with bilateral ONFH had lower mental scores, and male patients had worse social condition scores. Among patients with collapsed lesions, middle-aged patients exhibited lower mental QOL, and a strong correlation was observed between social activity and mental health. CONCLUSION: Collapsed ONFH was associated with low QOL scores. Among patients with non-collapsed lesions, alcohol-associated ONFH, bilateral disease, and male sex were linked to low QOL scores.

BACKGROUND: Preoperative planning is an important factor for total knee arthroplasty (TKA). The aim of this study is to document the interobserver and intraobserver reliability of computed tomography (CT)-based 3-dimensional (3D) preoperative planning for primary TKA. METHODS: Twenty knees (10 with osteoarthritis and 10 with rheumatoid arthritis) were studied independently by 6 orthopedic surgeons using a CT-based 3D planning system. The measurements were made twice at more than 3-week intervals without any knowledge of their own previous measurements or those of the others. We assessed the femoral and tibial component sizes and the alignment of the femoral component. RESULTS: The interobserver and intraobserver agreements for femoral component size were 44.3% and 62.5% with exact size, and increased to 90.7% and 99.2% within one size difference; the intraclass correlation coefficients (ICCs) were 0.919 and 0.936, respectively. The interobserver and intraobserver agreements for tibial component size were 57.0% and 66.7% with exact size, and increased to 87.3% and 90.0% within one size difference; the ICCs were 0.909 and 0.924, respectively. The ICCs for femoral and tibial size were better in rheumatoid arthritis than in osteoarthritis. Interobserver ICC for femoral valgus angle was 0.807, and 0.893 for intraobserver reliability. Interobserver ICC of the femoral external rotation angle was 0.463, and 0.622 for intraobserver reliability. CONCLUSION: CT-based 3D preoperative planning for primary TKA has clinical implications for predicting appropriate size and alignment of the component in patients with osteoarthritis and rheumatoid arthritis.

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.

BACKGROUND: The Japanese Orthopaedic Association (JOA) has been surveying approximately 3000 orthopedic surgery hospitals and clinics with inpatient facilities nationwide to collect information on atypical femoral fractures (AFFs) and patient characteristics since 2010. The present study aims to examine radiographic images and clarify the relationship between radiographic and patient characteristics of patients with AFF and treatment status. METHODS: The study involved 1996 facilities certified as clinical training sites by the JOA and 912 clinics with inpatient facilities affiliated with the Japanese Clinical Orthopaedic Association (JCOA). Additional clinical data collection and radiographic image review were performed in patients aged 35 years or older who met the American Society for Bone and Mineral Research (ASBMR) case definition for AFF and received treatment at participating facilities registered with JOA in 2013. Radiographic images were evaluated in accordance with the ASBMR case definition. RESULTS: Radiographic images of 304 fractures in 304 patients were collected. Among them, 230 fractures were determined to be AFFs. The fracture site was the proximal third in 70 AFFs (30.4%), middle third in 157 AFFs (68.3%), and distal third in 3 AFFs (1.3%). Among patients with AFFs, 173 (75.2%) were treated with bisphosphonates (BPs) and 45 patients (19.6%) were not (unknown in 12 patients). Duration of use was three years or longer in 103 patients (59.5%) and between one and three years in 24 patients (13.9%). Radiographic beaking was observed in 149 fractures (86.1%) in patients treated with BPs and 17 fractures (37.8%) in patients who were not treated with BPs (odds ratio 11.3, 95% CI 5.7-22.3). CONCLUSIONS: Radiographic beaking was observed more frequently in patients treated with BPs than in patients not treated with BPs.

BACKGROUND: The purpose of this study is to clarify interobserver and intraobserver reliabilities of the three-dimensional (3D) templating of total hip arthroplasty (THA). METHODS: We selected preoperative computed tomography from 60 hips in 46 patients (14 men and 32 women) who underwent primary THA. To evaluate interobserver and intraobserver reliability, 6 orthopedic surgeons performed 3D templating twice over a 4-week interval. We investigated intraclass correlation coefficients (ICCs) and percent agreement of component size and alignment, comparing morphological differences in the hip. Reproducibility was also compared between groups with osteoarthritis (OA) and those with osteonecrosis (ON). RESULTS: The interobserver reliabilities for mean cup size and stem size were excellent, with ICC = 0.907 and 0.944, respectively. The value was significantly higher in the ON group than in the OA group. In the OA group, the reliability of cup size and alignment decreased in hips with severe subluxation. Percent agreement of stem size was significantly different between the shapes of femoral canal. For intraobserver reliability, the mean ICC of cup size was 0.965 overall, while the value in the ON group was significantly higher than in the OA group. The mean ICC of stem size was 0.972 overall. CONCLUSION: Computed tomography-based 3D templating showed excellent reliability for component size and alignment in THA. Deformity of the affected joint influenced the reliability of preoperative planning.

Introduction: Discogenic back pain remains poorly understood with respect to etiopathogenesis, despite being a considerable burden. We sought to examine the expression of vascular endothelial growth factor in injured intervertebral discs in rat caudal vertebrae. Methods: Forty-eight male Sprague Dawley rats were assigned to 2 groups according to disc puncture injury: puncture (n = 32) or non-puncture (n = 16). Disc puncture was performed percutaneously such that the incision would be in the primary plane of motion for the coccygeal discs 5-6, 6-7, and 7-8. A 26-gauge needle was used to puncture each disc 10 times. Punctured discs were examined histologically by hematoxylin and eosin staining at 1, 7, 14, and 28 days post-injury. Results: Vascular endothelial growth factor was localized immunohistochemically, and determined quantitatively using an enzyme-linked immunosorbent assay. Peak inflammation occurred on the 7th day post-injury, but tissue degeneration continued until day 28. Local expression of vascular endothelial growth factor tended to be highest in the annulus fibrosus on the 7th and 14th days after puncture injury. The level of vascular endothelial growth factor was highest 1-day post-injury, and then gradually decreased thereafter. Furthermore, vascular endothelial growth factor levels in the puncture group were significantly higher than those in the non-puncture control group (p < 0.05). Conclusions: We found increased expression of the inflammatory cytokine vascular endothelial growth factor in injured intervertebral discs, suggesting that vascular endothelial growth factor may be clinically important in discogenic back pain.