Novel susceptibility loci for steroid-associated osteonecrosis of the femoral head in systemic lupus erythematosus.

Osteonecrosis of the femoral head (ONFH) involves necrosis of bone and bone marrow of the femoral head caused by ischemia with unknown etiology. Previous genetic studies on ONFH failed to produce consistent results, presumably because ONFH has various causes with different genetic backgrounds and the underlying diseases confounded the associations. Steroid-associated ONFH (S-ONFH) accounts for one-half of all ONFH, and systemic lupus erythematosus (SLE) is a representative disease underlying S-ONFH. We performed a genome-wide association study (GWAS) to identify genetic risk factors for S-ONFH in patients with SLE. We conducted a two-staged GWAS on 636 SLE patients with S-ONFH and 95 588 non-SLE controls. Among the novel loci identified, we determined S-ONFH-specific loci by comparing allele frequencies between SLE patients without S-ONFH and non-SLE controls. We also used Korean datasets comprising 148 S-ONFH cases and 37 015 controls to assess overall significance. We evaluated the functional annotations of significant variants by in silico analyses. The Japanese GWAS identified 4 significant loci together with 12 known SLE susceptibility loci. The four significant variants showed comparable effect sizes on S-ONFH compared with SLE controls and non-SLE controls. Three of the four loci, MIR4293/MIR1265 [odds ratio (OR) = 1.99, P-value = 1.1 × 10-9)], TRIM49/NAALAD2 (OR = 1.65, P-value = 4.8 × 10-8) and MYO16 (OR = 3.91, P-value = 4.9 × 10-10), showed significant associations in the meta-analysis with Korean datasets. Bioinformatics analyses identified MIR4293, NAALAD2 and MYO16 as candidate causal genes. MIR4293 regulates a PPARG-related adipogenesis pathway relevant to S-ONFH. We identified three novel susceptibility loci for S-ONFH in SLE.

Extension of the Antero-Posterior Necrotic Regions Associated With Collapse Cessation in Osteonecrosis of the Femoral Head.

BACKGROUND: Collapse cessation is of utmost importance following a long period of collapse due to osteonecrosis of the femoral head (ONFH). This study investigated the relationship between collapse cessation and the extent of the necrotic regions of ONFH. METHODS: Overall, 74 patients who had symptomatic ONFH (collapse < 3 mm) at the first visit with a minimum follow-up of 3 years were included in this study. Patients were categorized based on collapse progression or cessation into the progression and stable groups. The extent of the antero-posterior (AP) and medio-lateral necrotic regions between the groups was assessed using sagittal and coronal sections of T1-magnetic resonance imaging. Additionally, the most effective cutoff value was determined from the receiving operating characteristic curve where collapse cessation could be obtained, while the survival rates were determined with collapse progression as the endpoints were evaluated. RESULTS: Overall, 45 and 29 patients were in the progression and stable groups, respectively. The AP and medio-lateral necrotic regions were significantly different (P < .01 and P < .01, respectively) between the progression and stable groups. A cutoff value of 62.1% of the AP necrotic regions was determined from the receiving operating characteristic curve analysis. The 5-year survival rates with collapse progression as the endpoints were 5.4 and 77.8% in the AP necrotic regions of ≥62.1 and <62.1%, respectively (P < .01). CONCLUSIONS: Cases with AP necrotic regions of ≤62.1% can be expected to have collapse cessation, which could be a useful index for ONFH treatment strategies. LEVEL OF EVIDENCE: Level IV.

A large preoperative pelvic oblique angle affects perception of leg length discrepancy after total hip arthroplasty.

BACKGROUND: In some cases, patients feel a perceived leg length discrepancy (P-LLD) despite no radiographic leg length discrepancy (R-LLD) after total hip arthroplasty (THA). We aimed to investigate the rate of postoperative P-LLD and the factors that cause postoperative P-LLD. METHODS: A retrospective study was conducted on 100 patients with R-LLD ≤5 mm after THA. Patients were classified into two groups based on P-LLD post-THA: group P (with P-LLD) and group E (without P-LLD). Relevant data on the general characteristics and radiological findings between the two groups were compared. RESULTS: We observed that 25 & 75% of patients belonged to group P and group E, respectively, with no significant difference in patient background. Postoperative Japanese Orthopedic Association (JOA) classification of pain and activities of daily living scores were significantly lower in group P than in group E (37.2 ± 3.9 vs. 39.1 ± 2.2, respectively; P = 0.013, and 16.2 ± 4.2 vs. 18.2 ± 2.2, respectively; P = 0.011). The preoperative pelvic oblique angle (POA) was significantly larger in group P than in group E (3.3 ± 2.3° vs. -0.2 ± 2.1°; respectively; P < 0.01). The pelvis tilted toward the surgical side was significantly higher in group P than in group E(88% vs 57%; respectively; P = 0.013). The preoperative C7 coronal vertical axis (C7 CVA) was significantly larger in group P than in group E (6.7 ± 14.7 mm vs. -0.2 ± 10.3 mm; respectively; P = 0.028). Multivariate logistic analysis revealed that preoperative POA (OR, 3.71; 95% CI: 1.86-8.12; P < 0.01) and the pelvis tilted toward the surgical side (OR, 4.14; 95% CI: 2.07-9.71; P = 0.022) were independent risk factors for P-LLD after THA. CONCLUSION: Even though there was no postoperative R-LLD, 25% of patients had P-LLD. A large preoperative POA and the pelvis tilted toward the surgical side were independent risk factors for P-LLD after THA.

Risk factors for lateralization or superiorization of the center of the femoral head in eccentric rotational acetabular osteotomy.

PURPOSE: This study aimed to clarify the factors that cause the lateralization and superiorization of the femoral head after eccentric rotational acetabular osteotomy (ERAO) by examining the three-dimensional morphology of the osteotomy site using computed tomography (CT). METHODS: This study included 52 patients who underwent ERAO for hip dysplasia. Postoperatively, the center of the femoral head was measured for lateralization and superiorization. We defined the iliac and sciatic osteotomy angles in the coronal and axial CT planes, respectively. The surgical factors for lateralization and superiorization were analysed using multiple logistic regression analysis. We also analysed the relationship between the femoral head relocation and clinical outcomes (as assessed using Japanese Orthopaedic Association (JOA) scores). RESULTS: Thirty-five patients had hips with lateralized femoral heads, and 25 patients' femoral heads were superiorized. Logistic regression analysis revealed that a higher osteotomy angle of the ilium in the coronal plane served as a significant predictor of superiorization of the femoral head. Similarly, a larger osteotomy angle of the ischium in the axial plane and the amount of change in the lateral centre edge angle were identified as predictors of lateralization. A weak negative correlation was observed between the amount of lateralization and the JOA score. CONCLUSION: Large osteotomy angles in the superior and posterior aspects of the acetabulum carry a risk of superiorization and lateralization of the center of the femoral head. Surgeons should be aware of the need to chisel through the internal plate to achieve the results described in the ERAO theory. STUDY DESIGN: A single-center, retrospective study.

The survey of bone allograft transplantation in a Japanese regional bone bank.

BACKGROUND: In reconstructive surgery for large bone defects, the demand for bone allografts has increased over the years; however, it is unclear how the supply and demand in Japanese regional bone banks have evolved over time. This study investigated the 15-year supply and demand of bone allografts stored in a regional bone bank, along with assessing the screening process's effectiveness. METHODS: The target period was 15 years from April 2005 to March 2020. The period was subdivided into three 5-year periods: first, second, and third. The study items included the number of bone allografts donated, the number of bone allografts used, donor and user facilities, surgical methods using bone allografts, and the number of bone allografts discarded. We used the Cochran-Armitage test for statistical analysis. RESULTS: A total of 1852 bone allografts were donated to the bone bank, and a total of 1721 were used. A total of 677 bone allografts grafts were provided in the first period, 738 in the second period, and 525 in the third period, indicating a decreasing trend. The average number of allografts per surgery was 2.8 in the first, 3.1 in the second, and 1.7 in the third, showing a decreasing trend. Concerning the percentage of each surgery using bone allografts, spine fusion decreased in the third period but not significantly, whereas primary hip arthroplasty increased significantly in the third period. The total number of discarded bone allografts was 4.8% of the total number of donated bone allografts, largely because of a lack of screening tests. CONCLUSION: Although the number of allogeneic bone surgeries has been increasing over time, the number of allogeneic bone donations has shown a decreasing trend, and there is a need to develop a system that can provide surgeons with sufficient bone allografts.

Metabolic syndrome reduces spinal range of motion: The Yakumo study.

BACKGROUND: Excess visceral fat can accumulate owing to lack of exercise. The relationship between metabolic syndrome (MetS) and spinal range of motion (ROM) is not clear. The purpose of this study was to investigate the relationship between MetS and spinal alignment and ROM. METHODS: Orthopedic evaluation was prospectively performed in 544 participants. The participants were classified into two groups on the basis of the Japanese-specific MetS criteria proposed by the Japanese Committee of the Criteria for MetS (JCCMS). Lower back pain (LBP), knee joint pain with the visual analog scale (VAS), Kellgren-Lawrence (K-L) grade for knee osteoarthritis, body mass index (BMI), and spinal alignment and ROM were evaluated. RESULTS: Forty-four (8.1%) were diagnosed as having MetS. The prevalence rate of K-L grade 4 in the MetS group was significantly higher than that in the non-MetS group (p < 0.05). When sex, age, and BMI were evaluated as covariates, there were significant differences in the VAS score for knee pain (non-MetS group vs MetS group: 13.7 vs 23.3, p < 0.05), L1-S1 flexion spinal ROM (44.1° vs 38.1°, p < 0.001), flexion spinal inclination angle (SIA) ROM (107.6° vs 99.3°, p < 0.01), and SIA ROM (135.4° vs 124.0°, p < 0.05). CONCLUSIONS: Knee pain increased and flexion spinal ROM decreased significantly in the MetS group as compared with non-MetS group. Systemic factors associated with MetS may have a specific impact on spinal ROM while promoting knee osteoarthrosis and increased knee pain.

Factors affecting sports participation after total hip arthroplasty.

PURPOSE: The purpose of this study was to investigate the rate of return to sports after total hip arthroplasty (THA) in patients who regularly participate in sports and evaluate the factors that can affect the return to sports. METHODS: In total, 165 patients who had been continuously participating in sports prior to surgery were included from a total of 401 patients who underwent THA from 2015 to 2018. The mean follow-up was 3.3 (range, 2-6) years. Demographics, medical history, surgical parameters, functional outcomes, and anxiety about complications at the final follow-up were compared between the patients who participated in the same sports as before surgery (S group) and those who could not (N group). RESULTS: The overall return to sports rate was 79% for 68 (41%) and 97 (59%) patients in the S and N groups, respectively. The most common sports that patients participated in post-operatively were walking (76 patients, 46%) and swimming (37 patients, 22%), followed by muscle training (25 patients, 15%). There were significant differences between the groups in the following patient factors: sex, primary disease, post-operative Japanese Orthopedic Association Hip-Disease Evaluation Questionnaire outcome, and anxiety about falls and dislocation. In the evaluation of factors affecting return to sports using logistic regression analysis, male sex (odds ratio 3.66, 95% confidence interval 1.13-11.19, p = 0.029) and anxiety of dislocation (odds ratio 3.42, 95% confidence interval 1.58-7.42, p < 0.01) were extracted as independent risk factors. CONCLUSION: Careful patient guidance and rehabilitation, in addition to accurate surgical procedures, will improve patient participation in sports.

Bisphosphonate treatment is associated with decreased mortality rates in patients after osteoporotic vertebral fracture.

The aim of this study is to investigate the effect of bisphosphonate (BP) on mortality after osteoporotic vertebral fracture (OVF). BP medication (hazard ratios = 0.593; 95%CI: 0.361-0.976) was significantly associated with reduced all-cause mortality after OVF. PURPOSE: Osteoporotic vertebral fracture (OVF) is the most common type of fragility fracture. Bisphosphonate (BP) medication was suggested to have positive effects on both fracture prevention and recovery outcomes. The aim of this study is to investigate the effect of BP on mortality after OVF. METHODS: This cohort study involved 535 patients (170 males and 365 females), aged ≥ 65 years (mean age: 82.6 ± 7.0 years, mean follow-up periods: 33.0 ± 25.8 months) who were hospitalized after OVF from January 2011 to December 2019 at a public hospital. Patients treated with PTH (parathyroid hormone), PTH or PTHrp analogues, denosumab, and selective estrogen receptor modulators were excluded. Kaplan-Meier survival curves on mortality of patients with OVF with and without BP treatment were prepared, and log-rank tests were performed. Cox proportional hazards model was used to identify factors associated with mortality after OVF. RESULTS: This study included 163 (30.5%) patients treated with BP. Kaplan-Meier survival curves showed that the mortality rate after OVF was significantly lower in patients treated with BP (P < 0.001). Cox proportional hazards model showed that older age (hazard ratios [HR] = 1.066; 95%CI:1.035-1.103), male sex (HR = 2.248; 95%CI:1.427-3.542), malnutrition (geriatric nutritional risk index < 92) (HR = 1.691; 95%CI:1.005-2.846), BP medication (HR = 0.593; 95%CI: 0.361-0.976), and Japanese Orthopaedic Association score at discharge (HR = 0.941; 95%CI: 0.892-0.993) were significantly associated with all-cause mortality after OVF. CONCLUSIONS: BP medication is beneficial not only for fracture prevention but also for mortality after OVF.

Effect of trochanter displacement on impingement and bone contact in total hip arthroplasty performed after curved intertrochanteric varus osteotomy for osteonecrosis of the femoral head: a simulation study.

BACKGROUND: Curved intertrochanteric varus osteotomy (CVO) is a useful treatment option for osteonecrosis of the femoral head (ONFH). However, the effect of proximal femoral deformity in cases of CVO converted to total hip arthroplasty (THA) remains unclear. The aim of this study was to evaluate the effect of trochanter displacement on impingement and the contact state of the implant and femur in THA. METHODS: Thirty-eight hips that had undergone CVO for ONFH were reviewed and compared with a control group of 30 contralateral hips that had not undergone surgery. The range of motion (ROM) and impingement patterns and the percentage of cortical bone in the stem placement within the femur were measured by simulation using CT-based three-dimensional template software. We also measured the ROM and the number of joints that achieved the ROM required for activities of daily living when the upward displaced apex of the greater trochanter with osteotomy was resected and compared the findings with those obtained when the apex was not resected. RESULTS: The CVO group showed a significantly greater bony impingement in external rotation (68.4% vs. 43.3%, p = 0.033) and abduction (78.9% vs. 33.3%, p < 0.001) than in the control group. The CVO group showed a significantly smaller range of external rotation (19.0° [interquartile range; 4.0-28.8] vs. 38.0° [interquartile range; 36.0-41.8], p < 0.001) and abduction (23.0° [interquartile range; 8.5-38.8] vs. 56.0° [interquartile range; 50.3-60.0], p < 0.001) than in the control group. Significantly more joints achieved the ROM necessary for activities of daily living when the apex was resected than when it was not (10.5% vs. 63.2%, p < 0.001). The percentage of cortical bone in the stem placement position was significantly higher in the CVO group than in the control group in the proximal portion of the stem (25.5% vs. 0.0%, p < 0.001). CONCLUSION: In cases requiring conversion to THA, we recommend resecting the upward displaced apex to achieve a sufficient ROM and carefully resecting the bone to avoid malignment of the stem.

Factors influencing inconsistent leg length discrepancy in dysplastic hip osteoarthritis: a retrospective study.

BACKGROUND: We aimed to examine the inconsistency between radiographic leg length discrepancy (R-LLD) and perceived LLD (P-LLD) in patients with dysplastic hip osteoarthritis and to evaluate the factors that can cause such inconsistency. METHODS: We conducted a retrospective study on 120 patients. An inconsistent LLD was defined as a condition in which the P-LLD was shorter than the R-LLD by > 5 mm. We compared relevant data on the general characteristics of the patients and the radiological findings between consistent (group E, 92 cases [76.7%]) and inconsistent LLDs (group S, 28 cases [23.3%]). RESULTS: The number of patients with a history of hip surgery on the affected side and the Japanese Orthopedic Association classification pain scores were significantly higher in group S than in group E (32.1% vs. 10.8%, respectively; P = 0.015, and 21.7 ± 7.0 vs. 17.5 ± 8.2, respectively; P = 0.036). The pelvic oblique angle and length of the R-LLD were significantly higher in group S than in group E (2.9 ± 2.5° vs. 0.3 ± 2.3°, respectively; P < 0.01, and 17.2 ± 8.9 mm vs. 6.3 ± 8.4 mm, respectively; P < 0.01). Multivariate logistic analysis revealed that the pelvic oblique angle (odds ratio [OR]: 1.80, 95% confidence interval [CI]: 1.28-2.52; P < 0.01) and length of the R-LLD (OR: 2.75, 95% CI: 1.24-6.12; P = 0.013) were independent risk factors of inconsistent LLD. CONCLUSION: The pelvic oblique angle and a long R-LLD were independent risk factors of inconsistent LLD in patients with dysplastic hip osteoarthritis. Therefore, hip surgeons should consider P-LLD rather than R-LLD to understand the need for conservative intervention.

Association between locomotive syndrome and fall risk in the elderly individuals in Japan: The Yakumo study.

BACKGROUND: Patients with locomotive syndrome (LS) are poor ambulatory status and a high risk of requiring nursing care. The purpose of this study is to investigate the relationship between LS and fall risk among community-dwelling elderly individuals. METHODS: The subjects were Japanese elderly individuals aged 65 and over who participated in Yakumo study 2019 (N = 189). We defined the fall risk index 5 items version (FRI-5) ≥6 points as the fall risk group. LS was evaluated by stand-up test, two-step test, and 25-Geriatric Locomotive Function Scale (GLFS-25). We divided the subjects into two groups according to the presence or absence of fall risk, and investigated factors associated with fall risk. RESULTS: The fall risk group (30 patients, 15.9%) had higher GLSF-25 (P = 0.001). The results of logistic regression analysis adjusted for age, sex, BMI, and knee osteoarthritis revealed that GLFS-25 (OR: 1.052; 95%CI: 1.009-1.097) was independent factor associated with fall risk. In the ROC analysis, the optimal cut-off value of the GLFS-25 to predict fall risk was 12, which is equivalent to LS stage 1 (AUC 0.688; 95% CI: 0.588-0.787; sensitivity: 0.467, specificity: 0.836). CONCLUSIONS: GLFS-25 was associated with fall risk among community-dwelling elderly individuals aged 65 and over.

A preliminary examination of the association between locomotive syndrome and circulating miRNA-199 in community-dwelling people: The Yakumo study.

BACKGROUND: The risk of locomotive syndrome (LS) has been proposed as a criterion for evaluating physical ability. The expression levels of circulating miRNAs (c-miRNAs) are predictors of various diseases. This preliminary study aimed to evaluate the relationship between serum levels of several miRNAs and LS. METHODS: We enrolled 423 participants in whom we conducted a survey with the 25-question Geriatric Locomotive Function Scale (GLFS-25) and measured the serum levels of 21 c-miRNAs. The relationship between the GLFS-25 and each c-miRNA was evaluated with a linear regression analysis, and independent associations between the GLFS-25 and each c-miRNA were assessed with a multiple regression analysis using various independent variables. RESULTS: Only the serum level of miR-199 was significantly associated with LS after adjustment for age, BMI, sex, and all comorbidities. The receiver operating characteristics curve for the predictive value of the miR-199 level to indicate the presence or absence of LS risk had an area under the curve (AUC) of 0.576 (95% confidence interval: 0.501-0.651). CONCLUSION: The expression level of miRNA-199 was associated with the risk of LS in community-dwelling Japanese people.

The development of knee osteoarthritis and serum carotenoid levels among community-dwelling people in Japan.

OBJECTIVES: Carotenoids are plant pigments found in many vegetables, functioning as antioxidants scavenging singlet molecular oxygen and peroxyl radicals. No longitudinal study exists on the relationship between carotenoids and knee osteoarthritis (KOA) development. We aimed to determine the incidence of KOA development for 10 years in community-dwelling people in Japan and assess its association with serum carotenoids. METHODS: Data of 440 participants (174 men, 266 women) with health-screening records for at least 10 years were analysed. We defined KOA development as advancing from K/L grade 0/1 at the initial check-up to grade ≥2 in a unilateral knee during a 10-year follow-up period. Serum carotenoid levels were measured using high-performance liquid chromatography. We used the Cox hazard model for multivariate analysis and investigated each carotenoid's impact on KOA development. RESULTS: KOA developed in 33.4% of patients; the annual KOA development rate was significantly higher among women than among men (p < .01; 3.4% vs. 1.6%). Among the carotenoids measured, only retinol was associated with KOA development in women using multivariable analysis. KOA development was not associated with any carotenoids in men. CONCLUSION: The annual rate of KOA development was higher in women, and retinol was associated with KOA development in women.

Differences in the prevalence of locomotive syndrome and osteoporosis in Japanese urban and rural regions: The Kashiwara and Yakumo studies.

OBJECTIVES: To clarify whether the prevalence of locomotive syndrome (LS) and osteoporosis differed according to region, gender, and physical functions in Japan. METHODS: Data were collected in Kashiwara City (urban region) and Yakumo Town (rural region). Totally, 208 participants from the urban region and 782 participants from the rural region were included in this study. LS was assessed using the 25-item Geriatric Locomotive Function Scale and osteoporosis was assessed using a quantitative ultrasound. Physical functions were measured using grip strength and the 3-m timed up-and-go test. Differences between urban and rural regions were investigated using standardized incidence ratio and multivariate analysis. RESULTS: The prevalence of LS and osteoporosis was 24.5% and 42.8% in the urban region and 10.9% and 28.8% in the rural region, respectively. The standardized incidence ratio of the urban region versus the rural region was 1.80 (95% confidence intervals [CI] = 1.35-2.39) for LS and 1.21 (95% CI = 1.32-2.43) for osteoporosis, showing that the prevalence of LS was significantly higher in the urban region. Multivariate analysis indicated that LS was significantly associated with the urban sample and timed up-and-go was significantly longer in the urban sample. CONCLUSION: Regional differences may be considered when evaluating LS in health checkups. Understanding the results of this study may help reduce LS prevalence.

Effects of body mass index and range of motion on intraoperative change in pelvic tilt during total hip arthroplasty using the direct anterior approach.

BACKGROUND: Intraoperative pelvic tilt changes that occurs during total hip arthroplasty (THA) in the supine position affects cup placement and sometimes causes malalignment. The relationship between body mass index (BMI) and pelvic movement has been reported for some procedures, but not the direct anterior approach (DAA). The purpose of this study was to investigate intraoperative pelvic tilt changes that occurs during DAA. METHODS: In this single-center, retrospective study, we reviewed 200 hips that underwent primary THA via DAA in the supine position using an accelerometer-based navigation system. Intraoperative changes in pelvic tilt and axial rotation from the start of surgery to cup placement were assessed using the navigation system. Preoperative clinical factors that increased pelvic tilt and axial rotation toward the surgical side by > 10° were analyzed via univariate and multiple logistic regression analyses. RESULTS: The mean pelvic tilt value increased by 7.6° ± 3.8° (95% confidence interval [CI], 7.1-8.2; range, - 5.0-19.0) intraoperatively, and the axial rotation increased by 3.2° ± 2.7° (95% CI, 2.7-3.7; range, - 13.0-12.0). Univariate analysis revealed that the group with increased pelvic tilt showed significantly greater range of abduction and internal rotation, and significantly lower BMI than the group with no increased tilt. Pre-incisional pelvic tilt was significantly greater in the group with increased axial rotation than in the group with no increased rotation. On logistic regression analysis, BMI (odds ratio [OR], 0.889; 95% CI, 0.809-0.977; p = 0.014) and the range of internal rotation (OR, 1.310; 95% CI, 1.002-1.061; p = 0.038) were predictors of large increases in pelvic tilt. No predictors of large increases in axial rotation were identified. CONCLUSION: Significant forward pelvic tilt was observed in patients with a low BMI values and high ranges of internal rotation via THA using the DAA. Findings indicated that surgeons should pay attention to intraoperative pelvic movements, which may help identify patients with significant pelvic tilt changes.

Low muscle mass affect hip fracture treatment outcomes in older individuals: a single-institution case-control study.

BACKGROUND: Although sarcopenia has been known as a risk factor for hip fracture, only a few reports have described the impact of muscle mass on hip fracture treatment outcomes. The current study aimed to investigate the impact of muscle mass on hip fracture treatment outcomes. METHODS: This case-control study involved 337 patients (67 males and 270 females) with hip fracture aged ≥65 years (mean age: 84.1 ± 7.1 years) who underwent orthopedic surgery from January 2013 to June 2019. The mean follow-up period was 17.1 (1-60) months. Upon admission, all patients were assessed for low muscle mass according to the Asian Working Group for Sarcopenia criteria (male, SMI < 7.00 kg/m2; female, SMI < 5.40 kg/m2) using dual-energy X-ray absorptiometry. Treatment outcomes (stays at acute care institutions, hospital mortality, the Barthel index at discharge, and home discharge rates, and one-year mortality) were compared between patients with and without low muscle mass by Student's t-test, Mann-Whitney U test and the Pearson Chi-Square test. A multivariate logistic regression model was used to calculate adjusted odds ratios (ORs) with 95% confidence intervals (CIs) for factors related to low muscle mass. Kaplan-Meier survival curves on one-year mortality of hip fracture patients for those with and without low muscle mass were prepared, and log-rank tests were performed. Furthermore, we determined whether low muscle mass was a risk factor for one-year mortality in hip fracture patients using a Cox proportional hazards model. RESULTS: The prevalence of low muscle mass in patients with hip fracture was 231(68.5%). Those with low muscle mass had a lower Barthel index (P < 0.0001), hospital discharge rate (P = 0.035) and higher one-year mortality (P = 0.010). Cox proportional hazards regression analysis adjusted for age and sex found that low muscle mass was a risk factor for one-year mortality (hazard ratio, 3.182, 95% confidence interval, 1.097-9.226, P = 0.033). CONCLUSIONS: Patients with hip fracture who had low muscle mass had a lower Barthel index, lower home discharge rate, and higher one-year mortality. Moreover, low muscle mass was identified as a risk factor for one-year mortality among those with hip fracture. The aforementioned findings may help clinicians better manage those with hip fracture.

Collapse Progression or Cessation Affects the Natural History of Contralateral Osteonecrosis of the Femoral Head.

BACKGROUND: It is unclear how the condition of one side of the hip joint affects the natural history of contralateral osteonecrosis of the femoral head (ONFH). This study aimed to investigate the natural progression of bilateral ONFH on the asymptomatic side between patients with collapse progression and cessation on the symptomatic side. METHODS: The study included 109 patients with bilateral ONFH at the first visit, who were divided into two groups in accordance with the symptomatic side based on the collapse progression of ≥3 mm (progressive group: 74 hips) and collapse cessation of <3 mm (stable group: 35 hips) with a minimum follow-up of 3 years. The assessment parameters included age, gender, body mass index, etiology, type classification, and survival rates of the asymptomatic side with radiographic failure as the endpoints. RESULTS: Age, gender, body mass index, and etiology were not different between the two groups; however, a difference was observed in the type classification of the symptomatic side. The 4-year survival rates were significantly different between the progressive (34.3%) and stable groups (85.7%). Multivariate Cox regression analysis showed that age <40 years (vs ≥40 years; hazard ratio [HR], 2.439), type C2 (vs B + C1; HR, 2.865), and collapse progression on the symptomatic side (vs collapse cessation; HR, 7.751) were independent factors determining collapse on the asymptomatic side. CONCLUSION: Collapse progression on the symptomatic side is a poor prognostic factor for the natural history of contralateral ONFH.

Risk Factors for Neuropathic Pain in Middle-Aged and Elderly People: A Five-Year Longitudinal Cohort in the Yakumo Study.

OBJECTIVE: To determine the risk factors for new neuropathic pain (NeP) after five years in healthy middle-aged and elderly volunteers. DESIGN: Prospective longitudinal cohort study (Yakumo study). SETTING: Clinical evaluation in a health checkup. SUBJECTS: A total of 366 people (male N = 146, female N = 220, average age = 63.5 years) who did not have NeP in 2013 were examined. METHODS: NeP was diagnosed based on a painDETECT questionnaire score ≥13. Body mass index (BMI), comorbidity, low back pain (LBP), sciatica, physical ability, grip and back muscle strength, osteoporosis, sarcopenia, frailty, spinal alignment, and quality of life (QOL) with the SF36 in 2013 were compared between NeP(+) and NeP(-) subjects in 2018 using multivariate logistic regression analysis. RESULTS: The NeP(+) rate in 2018 was 5.2%, with no significant differences in age and gender. NeP(+) subjects had significantly lower BMI, severe sciatica, poor gait ability, higher rates of osteoporosis and sarcopenia, greater lumbar kyphosis and spinal inclination, and poorer mental health in 2013. Poor gait ability (odds ratio [OR] = 8.05), low BMI (OR = 2.31), lumbar kyphosis (OR = 1.38), low percentage of the young adult mean (OR = 1.15), and low mental QOL (OR = 1.06) were identified as significant and independent risk factors for new NeP after five years. CONCLUSIONS: This longitudinal cohort study identified five independent risk factors for development of new NeP after five years, with related factors of spinal inclination, sarcopenia, and sciatica. New NeP may be prevented by intervention or treatment of these factors at an early stage in relatively healthy middle-aged and elderly people.

Impact of pelvic incidence on lumbar osteophyte formation and disc degeneration in middle-aged and elderly people in a prospective cross-sectional cohort.

PURPOSE: Pelvic incidence (PI) is unique to each individual and does not change throughout life. High PI is related to lumbar spondylolisthesis, but associations of PI with lumbar osteophyte formation and disc degeneration are unclear. The objective was to evaluate relationships of PI with lumbar osteophyte formation and disc degeneration, as well as spinal sagittal alignment and geriatric diseases, in middle-aged and elderly people. METHODS: A total of 1002 volunteers (male: 434, female: 568, average age: 63.5) were prospectively examined for lumbar osteophyte formation (Nathan class ≥ 2) and disc degeneration (disc score ≥ 3). High (PI > 51, n = 501) and low (PI ≤ 51, n = 501) PI groups were defined. Clinical factors, frailty, sarcopenia, and physical quality of life (QOL) were compared between these groups, and risk factors for lumbar osteophyte formation and disc degeneration were identified in multivariate logistic regression analysis. RESULTS: Physical QOL was poorer in people with lumbar osteophyte formation (54.8%) and disc degeneration (33.6%). Age, male gender, spinal parameters including PI, bone mineral density, back muscle strength, and gait ability differed significantly between the groups, whereas frailty and sarcopenia were not significantly different. Low PI, low lumbar lordosis, elder age, male gender, high BMI, and weak back muscle strength were significant risk factors for lumbar osteophyte formation and disc degeneration. CONCLUSIONS: Low PI was identified as a risk factor for lumbar osteophyte formation and disc degeneration, both of which reduce physical QOL in middle-aged and elderly people. These slides can be retrieved under Electronic Supplementary Material.

Long-Term Outcomes of Eccentric Rotational Acetabular Osteotomy Combined With Femoral Osteotomy for Hip Dysplasia.

BACKGROUND: This study aimed at investigating the clinical outcomes of eccentric rotational acetabular osteotomy (ERAO) combined with intertrochanteric valgus osteotomy (ITVO) over a period of more than 10 years. METHODS: This is a case-control study of 39 patients (40 hips) who underwent ERAO combined with ITVO for hip dysplasia (ITVO group). Patients were matched for age, sex, follow-up period, and preoperative joint stage to 78 patients (80 hips) who underwent ERAO alone (ERAO group). We compared the clinical and radiographic outcomes and the survival rates between the groups. RESULTS: The Harris Hip Score at the final follow-up was significantly lower in the ITVO group than in the ERAO group. The postoperative center edge angle, acetabular head index, and minimum joint space were significantly smaller in the ITVO group than in the ERAO group. The survival rates for the conversion to total hip arthroplasty end point were not significantly different between groups. However, survival rates for the Harris Hip Score < 80 end point were significantly poorer in the ITVO group than in the ERAO group. CONCLUSION: The long-term results of ERAO combined with ITVO were not satisfactory from a hip function perspective. ERAO combined with ITVO should be indicated in only young active patients with pre-osteoarthritis and initial stages of osteoarthritis.