A crossover comparison of patient satisfaction with two teriparatide regimens: primary results of the Japanese Osteoporosis Intervention Trial 06 (JOINT-06).

INTRODUCTION: This study aimed to compare treatment satisfaction with two dosing regimens (two teriparatide [TPTD] self-injection systems) in osteoporosis patients at high risk of fracture. MATERIALS AND METHODS: In this open-label crossover randomized trial comparing self-injected once-daily (1/D)-TPTD with self-injected twice-weekly (2/W)-TPTD, three satisfaction variables were evaluated by questionnaire for 2 years. The primary endpoint was overall satisfaction and secondary endpoints were satisfaction with treatment effectiveness and with utility of the self-injection device. Changes in quality of life (QOL) assessed by EuroQol-5 Dimension, pain assessed by visual analogue scale (VAS), and anthropometric parameters were also analyzed. Safety was evaluated based on the incidence and severity of adverse events (AEs). RESULTS: The 1/D-TPTD and 2/W-TPTD groups consisted of 180 (75.9 ± 7.3 years) and 179 (age: 75.5 ± 6.9 years) patients, respectively. After 26 weeks of treatment, no significant between-group difference in the persistence rate (79.4% vs 72.6% in the 1/D-TPTD and 2/W-TPTD groups, respectively), distributions of overall satisfaction scores, and satisfaction with treatment (p > 0.05) were observed. However, several items of satisfaction with the utility of the injection device were significantly higher in the 2/W-TPTD group (p < 0.05). Statistical improvements from baseline values were observed in QOL and pain VAS in both groups (p < 0.05). No serious AEs were reported. CONCLUSION: The between-group similarity of overall treatment satisfaction and effectiveness scores and between-group difference in satisfaction with the utility of the self-injection device was useful information for real-world treatment of osteoporosis. Both medication regimens were well tolerated.

Cooperation between physicians and dentists for osteonecrosis of the jaw: a 2022 Japanese survey.

INTRODUCTION: A 2015 survey of the Japan Osteoporosis Society (JOS) on medication-related osteonecrosis of the jaw (MRONJ) revealed that cooperation between physicians and dentists was poor. Discontinuation of antiresorptive agents before tooth extraction was found to increase adverse events without preventing MRONJ. We compared this 2015 survey with a new survey conducted in 2022 to investigate cooperation between physicians and dentists for MRONJ. MATERIALS AND METHODS: A web-based structured questionnaire including 13 key queries was sent to 3813 physicians who were members of JOS, and 1227 (32.2%) responses were received. RESULTS: Of the 1227 respondents, 909 (74.1%) had complied with a discontinuation request from a dentist before tooth extraction, although 25.4% of medications were not related to the incidence of MRONJ. Of these, 177 respondents reported 252 adverse events including 10 (1.3%) cases of MRONJ. The prevalence of fractures increased from 4.8% in 2015 to 8.2% in 2022. The rates of respondents who requested oral health care by a dentist before antiresorptive agent therapy and reported cooperation between physicians and dentists were 72.7% and 42.4% in 2022 compared with 32.9% and 24.8% in 2015, respectively. The rates of cooperation among the 47 prefectures in Japan were significantly different, ranging from 10.0 to 83.3% (p = 0.02). CONCLUSION: This study confirmed increased cooperation between physicians and dentists for MRONJ in Japan. However, a more equal distribution of cooperation across Japan is necessary to optimally manage MRONJ. Discontinuation of antiresorptive agents is no longer necessary because fractures during discontinuation continue to increase in Japan.

Increased incidence among the very elderly in the 2020 Niigata Prefecture Osteoporotic Hip Fracture Study.

INTRODUCTION: A 2015 study showed a decreasing trend in the incidence of osteoporotic hip fractures in Niigata Prefecture, Japan, which had been increasing. This study aimed to investigate the incidence of osteoporotic hip fractures in 2020, determine the long-term change in the incidence of hip fractures from 1985 to 2020, and assess whether the decline in fracture incidence since 2010 has continued. MATERIALS AND METHODS: We obtained data from the registration forms submitted by hospitals and clinics of patients who lived in Niigata Prefecture and were diagnosed with osteoporotic hip fracture through a survey conducted from January 1, 2020 to December 31, 2020. RESULTS: In 2020, 3,369 hip fractures were recorded in Niigata Prefecture. Although the overall incidence of age-specific hip fractures decreased, it increased in patients aged ≥ 90 years, regardless of sex. The proportion of patients receiving anti-osteoporosis drugs prior to hip fracture increased from 7.6% in 2004 to 17.3% in 2020. Notably, surgical treatment should be performed as early as possible, and the preoperative waiting time was 2.9 days, which was mainly due to holidays. CONCLUSION: The incidence of hip fractures in Niigata Prefecture has gradually increased over the past 35 years, with an increasing change observed in the very elderly recently in 2020. Although the treatment of osteoporotic hip fractures in Niigata Prefecture is adequate, improvements may include increasing the rate of adoption of osteoporosis treatment further and decreasing the number of days of preoperative waiting.

Relationship between the Hip Abductor Muscles and Abduction Strength in Patients with Hip Osteoarthritis.

This study aimed to determine which muscle the gluteus maximus, gluteus medius, gluteus minimus (Gmin), or tensor fasciae latae (TFL) contributes most to hip abduction strength and to identify effective sites for cross-sectional area (CSA) Gmin and TFL measurement in hip osteoarthritis (OAhip) patients. Twenty-eight patients with OAhip were included. The muscle CSA and volume were determined using magnetic resonance imaging. Peak isometric strength was determined using hand-held dynamometry. Muscle volumes were normalized to the total muscle volume of hip abductors. Multiple regression analysis was performed. The difference between the CSA of Gmin and TFL was calculated, and correlations with volume and muscle strength were determined. Gmin volume was related to abductor muscle strength (p=0.042). The peak CSA of the Gmin correlated with muscle volume and strength. The CSA of the TFL correlated with volume, with no difference between the CSA of the most protruding part of the lesser trochanter and peak CSA. Gmin volume was strongly related to abductor muscle strength. Peak CSA is a useful parameter for assessing the CSA of the Gmin among patients with OAhip. The CSA of the TFL should be measured at the most protruding part of the lesser trochanter.

Analysis of Phase Angle and Balance and Gait Functions in Pre-Frail Individuals: A Cross-Sectional Observational Study.

We measured the muscle mass and phase angle of each body part to evaluate the relationship between balance and gait functions in individuals with a pre-frailty status. This cross-sectional observational study determined the skeletal muscle mass-to-body weight ratio and phase angles of 21 control (robust) and 29 pre-frail subjects. Their Brief-Balance Evaluation Systems Test, Timed Up-and-Go (TUG) test, Life-Space Assessment, and Modified Fall Efficacy Scale scores plus the relationship between muscle mass, phase angle, and motor function were evaluated. In the pre-frailty group (three males, 26 females, aged 75.58±7.60 years), significant correlations were noted between the Brief-Balance Evaluation Systems Test score and lower-limb (r=0.614) and wholebody (r=0.557) phase angles, and between the TUG test score and lower-limb muscle mass-to-body weight ratio (r=-0.616), lower-limb phase angle (r=-0.616), and whole-body phase angle (r=-0.527). Evaluating the phase angle of the lower extremities of pre-frail patients and intervening accordingly may help clinicians maintain and improve these patients' balance and gait functions.

The Matsudai Knee Osteoarthritis Survey showed the longitudinal changes of knee phenotypes in alignment and structure during 23-28 years.

PURPOSE: The longitudinal changes in alignment and structure, including the joint line and cortical bone thickness (CBT) of the femur and tibia, and knee phenotype in patients with knee osteoarthritis (OA) remain unknown. The aim of this retrospective study was to clarify the longitudinal changes in matched healthy subjects. METHODS: The follow-up Matsudai Knee Osteoarthritis Survey was administered between 23 and 28 years. This study included 285 healthy knees from 235 females with an average age of 53 ± 6 years at baseline. The non-OA individuals, with an average age of 79 ± 4 years, were divided into three groups at baseline according to their follow-up radiographic results [the non-OA (n = 52), early OA (n = 131), and advanced OA groups (n = 102)]. Changes in alignment, joint line, CBT, and knee phenotype were assessed at baseline and at follow-up using standing anteroposterior radiographs. RESULTS: This study showed significant varus changes in the alignment (p < 0.001) and tibial and femoral joint line parameters (p < 0.05) in the OA group. Decreased CBT and increased mediolateral CBT ratios were observed in all groups (p < 0.001). The knee phenotypes in the OA groups were changed to varus angles, especially in the alignment and tibial joint line. CONCLUSIONS: The longitudinal changes of knee phenotypes in alignment and structure (CBT and joint line) from baseline to follow-up were shown in the OA groups. In addition, alignment and tibial structural factors at baseline are useful in predicting the incidence of knee OA in daily practice. LEVELS OF EVIDENCE: III.

Risks of femoral localized periosteal thickening in patients with autoimmune inflammatory rheumatic diseases.

OBJECTIVES: The incidence of femoral localized periosteal thickening (LPT), which can precede atypical femoral fracture (AFF), is not low (1-10%) in Japanese patients with autoimmune inflammatory rheumatic diseases (AIRDs). We explored the associations between underlying AIRDs and the prevalence of LPT. METHODS: We conducted post hoc analyses of two cohorts that included a total of 280 Japanese women, 105 of whom had AIRDs and had been taking bisphosphonate (BP) and prednisolone (PSL) and 175 of whom had rheumatoid arthritis (RA). RESULTS: LPT was detected in a total of 18 patients (6.4%) and 3 (1.1%) developed AFFs. RA was negatively correlated with LPT. A disease other than RA requiring glucocorticoid treatment, BP use ≥5 years, PSL use ≥7 years, and a PSL dose ≥5.5 mg/day were positively correlated with LPT. After adjusting for age, diabetes mellitus, and BP duration or daily PSL dose, RA was no longer associated with LPT. CONCLUSIONS: LPT in Japanese patients with AIRDs was associated with BP and glucocorticoid treatment rather than underlying AIRDs. When PSL dose ≥5.5 mg/day is required long-term [typically combined with long-term BP treatment (≥5 years)], clinicians need to pay particular attention in cases LPT and AFF as well as glucocorticoid-induced osteoporosis.

Diagnostic accuracy of fine needle aspiration cytology and core needle biopsy in bone and soft tissue tumor: A comparative study of the image-guided and blindly performed procedure.

INTRODUCTION: Fine needle aspiration cytology (FNAC) and core needle biopsy (CNB) can provide tissue samples for the diagnoses of bone and soft tissue tumors. We evaluated the diagnostic accuracy of FNAC and CNB, the usefulness of the image-guided needle procedures, and assessed whether a discordance can influence the prognosis. PATIENTS AND METHODS: We retrospectively examined the accuracy rates of FNAC and CNB procedures by analyzing results of 405 specimens of 389 patients. We evaluated the diagnostic accuracy of FNAC and CNB, compared the clinical effectiveness between the image-guided procedures and the blind procedures, and also compared survival rates between the true positive and the false negative cases for patients with high-grade malignant tumors. RESULTS: The accuracy rates of FNAC were 86.6% and 93.8% for CNB. In cases with non-palpable masses, there were significantly low sampling error rates in the image-guided procedure. There were no significant differences in progression-free-survival and overall survival rates in patients between the false negative and true positive cases. CONCLUSION: Both FNAC and CNB procedures had high accuracy rates. Limited to cases with no palpable masses, the image-guided procedure had a low sampling error rate and was an effective method for obtaining tissue samples.

Passive ankle motion and calf massage without anticoagulation therapy after total hip arthroplasty: A retrospective study.

BACKGROUND: It has been previously reported that manual calf massage and passive ankle motion after total hip arthroplasty could reduce the incidence of venous thromboembolism. However, a combination of chemical and mechanical prophylaxes was employed. In this study, we aimed to examine the effect of mechanical prevention without pharmacological antithrombotic intervention. METHODS: Of the 313 patients who underwent unilateral primary total hip arthroplasty and received passive ankle motion and calf massage postoperatively at our hospital between January 2015 and December 2019, 261 (58 men, 203 women; mean age 62.1 years) were included in this retrospective study. Pharmacological anticoagulation therapy was administered in 176 patients (combination group); 137 patients only underwent calf massage and passive ankle motion without anticoagulation therapy (single group). The study outcomes were operation time, the incidence of deep vein thrombosis, pulmonary thromboembolism, intraoperative bleeding, estimated actual blood loss, blood transfusion, and major bleeding. RESULTS: No significant differences were found in sex, age, side, platelet counts, activated partial thromboplastin time, prothrombin time, prothrombin time - International Normalized Ratio, intraoperative blood loss, estimated blood loss, and operation time. Moreover, the incidence of deep vein thrombosis, pulmonary thromboembolism, and intraoperative bleeding was not significantly different between the groups (deep vein thrombosis 4.0% vs. 6.3%, p = 0.244; pulmonary thromboembolism 0.7% vs. 0%, p = 0.548; and intraoperative bleeding 394 ± 173.6 ml vs. 365.4 ± 168.5 ml, p = 0.550). However, estimated actual blood loss and postoperative bleeding differed between the groups (eABL 996.6 ± 348.3 ml vs. 858.5 ± 269.6 ml, p = 0.003; postoperative bleeding 601.8 ± 330.0 ml vs. 492.1 ± 277.1 ml, p = 0.016), and both increased in the combination group. No major bleeding was noted in the two groups. CONCLUSION: Postoperative anticoagulant therapy does not have to be routinely used if mechanical prophylaxis is performed in patients without deep vein thrombosis before total hip arthroplasty.

Human leukocyte antigen I is significantly downregulated in patients with myxoid liposarcomas.

The characteristics of the tumor immune microenvironment remains unclear in liposarcomas, and here we aimed to determine the prognostic impact of the tumor immune microenvironment across separate liposarcomas subtypes. A total of 70 liposarcoma patients with three subtypes: myxoid liposarcoma (n = 45), dedifferentiated liposarcoma (n = 17), and pleomorphic liposarcoma (n = 8) were enrolled. The presence of tumor infiltrating lymphocytes (CD4+ , CD8+ , FOXP3+ lymphocytes) and CD163+ macrophages and expression of HLA class I and PD-L1 were assessed by immunohistochemistry in the diagnostic samples; overall survival and progression-free survival were estimated from outcome data. For infiltrating lymphocytes and macrophages, dedifferentiated liposarcoma and pleomorphic liposarcoma patients had a significantly higher number than myxoid liposarcoma patients. While myxoid liposarcoma patients with a high number of macrophages were associated with worse overall and progression-free survival, dedifferentiated liposarcoma patients with high macrophage numbers showed a trend toward favorable prognosis. Expression of HLA class I was negative in 35 of 45 (77.8%) myxoid liposarcoma tumors, whereas all dedifferentiated liposarcoma and pleomorphic liposarcoma tumors expressed HLA class I. The subset of myxoid liposarcoma patients with high HLA class I expression had significantly poor overall and progression-free survival, while dedifferentiated liposarcoma patients with high HLA class I expression tended to have favorable outcomes. Only four of 17 (23.5%) dedifferentiated liposarcomas, two of eight (25%) pleomorphic liposarcomas, and no myxoid liposarcoma tumors expressed PD-L1. Our results demonstrate the unique immune microenvironment of myxoid liposarcomas compared to other subtypes of liposarcomas, suggesting that the approach for immunotherapy in liposarcomas should be based on subtype.

Lower trabecular bone score is associated with an increased incidence of localized femoral periosteal thickening.

INTRODUCTION: Femoral localized periosteal thickening (LPT, also termed "beaking") of the lateral cortex often precedes an atypical femoral fracture (AFF). Bisphosphonate (BP) use, glucocorticoid use, and Asian race are major risk factors for developing such fractures. The aim of this study was to determine whether the trabecular bone score (TBS) reflecting the lumbar trabecular microarchitecture was related to LPT in glucocorticoid-treated Japanese patients with autoimmune diseases. MATERIALS AND METHODS: We retrospectively investigated 111 women with autoimmune diseases treated with prednisolone (PSL) who had undergone both femoral X-ray and dual-energy X-ray absorptiometry of the L1 - L4 lumbar vertebrae and for whom TBS could be evaluated for two or more of these. RESULTS: Femoral LPT was evident in the X-rays of 18 of 111 patients (16.2%). Higher body mass index (BMI), longer duration of PSL use and longer duration of BP use were significant in patients with LPT compared to those without. The TBS was significantly lower in patients with LPT than in those without (1.314 ± 0.092 vs. 1.365 ± 0.100, p = 0.044); however, the lumbar bone mineral density did not differ significantly (0.892 ± 0.141 vs. 0.897 ± 0.154 g/cm2, p = 0.897). TBS was significantly associated with LPT (odds ratio, 0.004; 95% CI, 0 - 0.96; p = 0.048), but not in the multivariate analysis including BMI, duration of PSL use and duration of BP use. CONCLUSIONS: The TBS was lower in glucocorticoid-treated Japanese women with autoimmune diseases with LPT than in those without LPT, and deteriorated trabecular microarchitecture influenced by longer use of BP and glucocorticoid might be associated with the development of LPT.

Sacral incidence to pubis: a novel and alternative morphologic radiological parameter to pelvic incidence in assessing spinopelvic sagittal alignment.

BACKGROUND: Although pelvic incidence (PI) is a key morphologic parameter in assessing spinopelvic sagittal alignment, accurate measurements of PI become difficult in patients with severe hip dislocation or femoral head deformities. This study aimed to investigate the reliability of our novel morphologic parameters and the correlations with established sagittal spinopelvic parameters. METHODS: One hundred healthy volunteers (25 male and 75 female), with an average age of 38.9 years, were analysed. Whole-body alignment in the standing position was measured using a slot-scanning X-ray imager. We measured the established spinopelvic sagittal parameters and a novel parameter: the sacral incidence to pubis (SIP). The correlation coefficient of each parameter, regression equation of PI using SIP, and regression equation of lumbar lordosis (LL) using PI or SIP were obtained. The intraclass correlation coefficient (ICC) was calculated as an evaluation of the measurement reliability. RESULTS: Reliability analysis showed high intra- and inter-rater agreements in all the spinopelvic parameters, with ICCs > 0.9. The SIP and pelvic inclination angle (PIA) demonstrated strong correlation with PI (R = 0.96) and pelvic tilt (PT) (R = 0.92). PI could be predicted according to the regression equation: PI = - 9.92 + 0.905 * SIP (R = 0.9596, p < 0.0001). The ideal LL could be predicted using the following equation using PI and age: ideal LL = 32.33 + 0.623 * PI - 0.280 * age (R = 0.6033, p < 0.001) and using SIP and age: ideal LL = 24.29 + 0.609 * SIP - 0.309 * age (R = 0.6177, p < 0.001). CONCLUSIONS: Both SIP and PIA were reliable parameters for determining the morphology and orientation of the pelvis, respectively. Ideal LL was accurately predicted using the SIP with equal accuracy as the PI. Our findings will assist clinicians in the assessment of spinopelvic sagittal alignment. TRIAL REGISTRATION: This study was retrospectively registered with the UMIN Clinical Trials Registry ( UMIN000042979 ; January 13, 2021).

Accuracy of Acetabular Cup Implantation, as a Function of Body Mass Index and Soft-tissue Thickness, with a Mechanical Intraoperative Support Device: A Retrospective Observational Study.

HipCOMPASS, a mechanical intraoperative support device used in total hip arthroplasty (THA), improves the cup-alignment accuracy. However, the alignment accuracy achieved by HipCOMPASS has not been specifically examined in obese patients. In this study, we retrospectively evaluated the relation between alignment accuracy and several obesity-related parameters in 448 consecutive patients who underwent primary THA using HipCOMPASS. We used computed tomography (CT) to measure the preoperative soft-tissue thickness of the anterior-superior iliac spine (ASIS) and pubic symphysis and the differences between preoperative and postoperative cup angle based on the cup-alignment error. We found significant correlations between the absolute value of radiographic anteversion difference and body mass index (r = 0.205), ASIS thickness (r = 0.419), and pubic symphysis thickness (r = 0.434). The absolute value of radiographic inclination difference was significantly correlated with ASIS (r = 0.257) and pubic symphysis thickness (r = 0.202). The receiver operating characteristic curve showed a pubic symphysis thickness of 37.2 mm for a ≥ 5° implantation error in both radiographic inclination and anteversion simultaneously. The cup-alignment error for HipCOMPASS was large in patients whose pubic symphysis thickness was ≥ 37.2 mm on preoperative CT. Our results indicate that methods other than HipCOMPASS, including computed tomography-based navigation systems, might be preferable in obese patients.

Multidisciplinary Approach to Reduce Postoperative Complications and Improve the Activity of Patients with Hip Fracture: A 24-month Follow-up Survey.

Multidisciplinary approaches such as fracture liaison services (FLS) have been introduced in some countries to reduce medical complications and secondary fractures in patients with fragility hip fracture. We aimed to investigate outcomes in patients with fragility hip fracture following the introduction of FLS. Patients > 50 years old who experienced fragility hip fractures between January 1, 2015 and December 31, 2017 were enrolled, and divided into a control group (without FLS; 94 patients) and FLS group (373 patients). We found that the time from injury to surgery decreased significantly from 2.42 to 1.83 days (p = 0.003), the proportion of patients who underwent surgery within 36 h of injury increased significantly (p = 0.014), and the number of cases with complications after admission decreased significantly (p = 0.004) in the FLS group. Patients with a Barthel index ≥ 80 were more common in the FLS than the control group at 6 , 12, and 24 months following injury (p = 0.046 , 0.018, and 0.048, respectively). Multiple logistic regression analysis revealed the factors associated with postoperative complications and death within 12 or 24 months after injury. Our results indicate that FLS contributed to earlier recovery, rehabilitation following surgery and rehabilitation of medical complications following admission; improved patient activity; and decreased secondary hip fractures.

Bone Histomorphometry of Femoral Head Cancellous Bone in Patients Who Underwent Total Hip Arthroplasties due to Destructive Hip in Rheumatoid Arthritis.

Rheumatoid arthritis (RA) affects the hip joints. The microarchitecture of the cancellous bone in RA-affected hip joints has been unclear. Here we investigated the bone metabolism changes in the subcapital cancellous bone of destructive hips of RA patients (n=26 patients; 28 hip joints) which were classified by Larsen grade on X-ray into the groups: destructive hip (Des) (Larsen grade IV, n=18) and neck fracture (Fx) (Larsen grade 0 or 1, n=10). The femoral heads of the Des-group showed significantly higher trabecular thickness versus those of the Fx-group (179±30.8 vs. 151±23.5 µm, p=0.02). The Des-group had significantly higher osteoid volume/tissue volume (OV/TV) and osteoid volume/bone volume (OV/BV) ratios than the Fx-group (OV/TV: 0.72±0.70% vs. 0.27±0.32%, p=0.028; OV/BV: 2.96±2.85% vs. 1.24±1.31%, p=0.039). The osteoblast and osteoclast surface areas of the Des-group were remarkably higher than those of the Fx-group (9.80±10.9 vs. 0.15±0.15%, p=0.0005; 0.34±0.48 vs. 0.06±0.06%, p=0.0285, respectively). The T-scores of hip (femoral neck) bone mineral density (BMD) of the Fx-group were significantly lower versus those of the Des-group (-3.1±0.76 vs. -1.6±1.17, p<0.01). Increased osteoid and resorption parameters and higher femoral neck BMD demonstrate a high bone-turnover state in response to destructive changes in the hips of RA patients.

Minimally Invasive Spinal Stabilization with Denosumab before Total Spondylectomy for a Collapsing Lower Lumbar Spinal Giant Cell Tumor.

A 21-year-old man consulted our hospital for treatment of a spinal giant cell tumor (GCT) of Enneking stage III. Lower lumbar-spine tumors and severe spinal canal stenosis are associated with high risk for surgical mor-bidity. Stability was temporarily secured with a percutaneous pedicle screw fixation in combination with deno-sumab, which shrank the tumor. Total en bloc spondylectomy was then performed 6 months after initiation of denosumab, and the patient was followed for 3 years. There was no local recurrence, and bony fusion was obtained. Minimally invasive surgery and denosumab allowed safer and easier treatment of a collapsing lower lumbar extra-compartmental GCT.

Predictive factors for developing osteochondritis dissecans after surgery for discoid lateral meniscus are younger age and shorter meniscal width.

PURPOSE: This study aimed to identify the predictive factors for postoperative osteochondritis dissecans (OCD) in juvenile and adolescent knees with discoid lateral meniscus (DLM). METHODS: In total, 242 patients with symptomatic DLM who underwent surgery were identified. Inclusion criteria were set as follows: (1) age ≤ 17 years with an open growth plate, (2) follow-up magnetic resonance imaging, and (3) absence of preoperative OCD. Consequently, 52 patients were retrospectively investigated. Average age during surgery, body mass index (BMI), and follow-up duration were 12 years [95% confidence interval (CI) 11-13], 19.2 kg/m2 (95% CI 18.4-20.1), and 27.3 months (95% CI 20.9-33.7), respectively. Age, sex, sports activities, BMI, symptomatic OCD in other joints, postoperative rehabilitation, preoperative shift of DLM by Ahn's classification, surgical procedures (saucerization alone or with stabilization, and subtotal meniscectomy), and postoperative meniscal width were analyzed as possible predictive factors. RESULTS: Postoperatively, 42 patients without OCD and 10 with OCD were observed. In univariate analysis, younger age [odds ratio (OR) 1.5; p = 0.003], subtotal meniscectomy (OR 6.3; p = 0.027), and shorter meniscal width (OR 2.7; p = 0.005) were predictive factors for postoperative OCD. Multivariate analysis demonstrated that younger age (OR 1.6; p = 0.009) and shorter meniscal width (OR 1.5; p = 0.003) were predictive factors. CONCLUSIONS: To prevent postoperative OCD after DLM surgeries, achieving stabilization with adequate meniscal width is necessary for juvenile knees. LEVEL OF EVIDENCE: III.

The postoperative shorter meniscal width was the risk factor of lateral meniscal extrusion in the middle portion for juvenile and adolescent knees with discoid lateral meniscus.

PURPOSE: The study aim was to clarify the risk factors for postoperative meniscal extrusion in a middle portion in juvenile and adolescent knees with DLM. METHODS: Forty-six patients with symptomatic DLM who underwent surgery were retrospectively assessed. Inclusion criteria were set as follows: (1) aged ≤ 17 years with an open growth plate, (2) preoperative and postoperative follow-up MRI, and 3) reshaping surgeries comprising of saucerization alone or with meniscal repair. Average (95%CI) age during surgery, body mass index (BMI), and follow-up duration were 12 years (11-13), 19.9 kg/m2 (18.7-21.0), and 26.4 months (19.5-33.3), respectively. Age, sex, sports activities, BMI, postoperative rehabilitation, preoperative shift of DLM by Ahn's classification, surgical procedures, postoperative meniscal width of all portions, and meniscal healing were analyzed. RESULTS: Postoperatively, eight knees in the no-extrusion group and 38 knees in the extrusion group were observed. In the univariate logistic regression analysis, shorter meniscal width in a middle portion (OR = 1.580, p = 0.006), shorter minimum width of all portions (OR = 1.674, p = 0.024), and meniscal healing (OR = 0.160, p = 0.028) were the risk factors for meniscal extrusion in a middle portion. Multiple logistic regression analysis demonstrated that shorter meniscal width in a middle portion was the risk factor. CONCLUSIONS: As the clinical relevance, to prevent postoperative meniscal extrusion of the middle portion with DLM, surgeons are necessary to pay attention to maintain the adequate meniscal width for juvenile and adolescent knees. LEVEL OF EVIDENCE: III.

Appropriate sites for the measurement of the cross-sectional area of the gluteus maximus and the gluteus medius muscles in patients with hip osteoarthritis.

PURPOSE: To evaluate the relationship between the volume, cross-sectional area, and peak isometric muscle strength of the gluteus maximus and gluteus medius muscles in patients with hip osteoarthritis, and to use this information to identify effective sites for measurement of the cross-sectional area of these muscles. METHODS: Twenty-four patients with hip osteoarthritis were included. The muscle cross-sectional area and volume were calculated from magnetic resonance images. The cross-sectional area was calculated at three levels: the inferior point of the sacroiliac joint, just above the femoral head, and at the greatest muscle diameter. Peak isometric strength was assessed using hand-held dynamometry, using the extension and external rotation for the gluteus maximus and abduction and internal rotation for the gluteus medius. Measured outcomes were compared between the two muscles, and the association between muscle volume, cross-sectional area, and peak isometric muscle strength was evaluated using Pearson's correlation. RESULTS: Volume was correlated with the cross-sectional area in the gluteus maximus (r ≥ 0.707) and with the cross-sectional area (r ≥ 0.637) and peak isometric strength (r ≥ 0.477) in the gluteus medius. There was no difference between the cross-sectional area measured at the greatest muscle diameter and just above the femoral head (p = 0.503) for the gluteus maximus and at the inferior point of the sacroiliac joint (p = 0.651) for the gluteus medius. CONCLUSION: The cross-sectional area, when used to calculate the muscle volume, should be evaluated just above the femoral head for the gluteus maximus and at the inferior point of the sacroiliac joint for the gluteus medius.

Age- and sex-related characteristics in cortical thickness of femoral diaphysis for young and elderly subjects.

INTRODUCTION: Cortical thickness of the femoral diaphysis is assumed to be a preferred parameter in the assessment of the structural adaptation by mechanical use and biological factors. This study aimed to investigate the age- and sex-specific characteristics in cortical thickness of the femoral diaphysis between young and elderly non-obese people. MATERIALS AND METHODS: This study investigated 34 young subjects (21 men and 13 women; mean age: 27 ± 8 years) and 52 elderly subjects (29 men and 23 women; mean age: 70 ± 6 years). Three-dimensional (3D) cortical thickness of the femoral diaphysis was automatically calculated for 5000-8000 measurement points using the high-resolution cortical thickness measurement from clinical CT data. In 12 assessment regions created by combining three heights (proximal, central, and distal diaphysis) and four areas of the axial plane at 90° (medial, anterior, lateral, and posterior areas) in the femoral coordinate system, the standardized thickness was assessed using the femoral length. RESULTS: As per the trends, (1) there were no differences in medial and lateral thicknesses, while the posterior thickness was greater than the anterior thickness, (2) the thickness in men was higher than that in women, and (3) the thickness in young subjects was higher than that in elderly subjects. CONCLUSIONS: The results of this study are of clinical relevance as reference points to clarify the causes of various pathological conditions for diseases of the lower extremities.