Characteristics of pelvic obliquity in dysplastic hip osteoarthritis.

PURPOSE: Factors affecting direction of pelvic obliquity (PO) in dysplastic hip osteoarthritis (DHOA) remains unclear. This retrospective cohort study evaluates morphological characteristics, spinal alignment, and hip function in patients with unilateral DHOA. METHODS: Between 2018 and 2022, 104 patients with unilateral DHA were enrolled. Patients were categorized into flat PO (F-PO group; PO < 2°), affected side PO (A-PO group; PO downward by ≥ 2°), and unaffected side PO (U-PO group; PO upward by ≥ 2°). Demographics, radiographic hip and lower limb parameters, spinal parameters, and functional scores were compared between the groups. RESULTS: There were 39, 44, and 21 patients in the F-PO, A-PO, and U-PO group, respectively. The subluxation percentage of Crowe classification showed a significant difference among the three groups. The femoral head lateralization distance was significantly greater in the U-PO group than in the F-PO and A-PO groups. Furthermore, the hip adduction angle was significantly lower in the A-PO group than in the F-PO and U-PO groups. The lumbar scoliosis angle was significantly different between the groups. In multivariate analysis, hip adduction angle was extracted as an independent factor associated with the A-PO. Age, subluxation percentage, and hip adduction angle were identified as independent factors associated with the U-PO. Harris hip score was significantly poorer in U-PO group than in F-PO group. CONCLUSIONS: Hip adduction angle influenced A-PO, while age, subluxation percentage, and hip adduction angle influenced U-PO; lumbar scoliosis angle was associated with PO direction. U-PO patients had poorer functional scores, indicating the impact of hip contracture and subluxation on PO direction in DHOA.

What Are the Sex-Based Differences of Acetabular Coverage Features in Hip Dysplasia?

BACKGROUND: Eccentric rotational acetabular osteotomy is performed to prevent osteoarthritis caused by developmental dysplasia of the hip (DDH). To achieve sufficient acetabular coverage, understanding the characteristics of acetabular coverage in DDH is necessary. However, the features of acetabular coverage in males with DDH remain unclear. We thought that the differences in acetabular coverage between females and males might be associated with the differences in pelvic morphology between the sexes. QUESTIONS/PURPOSES: (1) What are the differences in the acetabular coverage between females and males with DDH? (2) What are the differences in the rotations of the ilium and ischium between females and males with DDH? (3) What is the relationship between the rotation of the ilium and ischium and the acetabular coverage at each height in females and males with DDH? METHODS: Between 2016 and 2023, 114 patients (138 hips) underwent eccentric rotational acetabular osteotomy at our hospital. We excluded patients with Tönnis Grade 2 or higher, a lateral center-edge angle of 25º or more, and deformities of the pelvis or femur, resulting in 100 patients (122 hips) being included. For female patients (98 hips), the median (range) age was 40 years (10 to 58), and for the male patients (24 hips), it was 31 years (14 to 53). We used all patients' preoperative AP radiographs and CT data. The crossover sign, posterior wall sign, and pelvic width index were evaluated in AP radiographs. The rotation of the innominate bone in the axial plane was evaluated at two different heights, specifically at the slice passing through the anterior superior iliac spine and the slice through the pubic symphysis and ischial spine in CT data. Furthermore, we evaluated the anterior and posterior acetabular sector angles. Comparisons of variables related to innominate bone measurements and acetabular coverage measurements between females and males in each patient were performed. The correlations between pelvic morphology measurements and acetabular coverage were evaluated separately for females and males, and the results were subsequently compared to identify any sex-specific differences. For continuous variables, we used the Student t-test; for binary variables, we used the Fisher exact test. A p value less than 0.05 was considered statistically significant. RESULTS: In the evaluation of AP radiographs, an indicator of acetabular retroversion-the crossover sign-showed no differences between the sexes, whereas the posterior wall sign (females 46% [45 of 98] hips versus males 75% [18 of 24] hips, OR 3.50 [95% confidence interval (CI) 1.20 to 11.71]; p = 0.01) and pelvic width index less than 56% (females 1% [1 of 98] versus males 17% [4 of 24], OR 18.71 [95% CI 1.74 to 958.90]; p = 0.005) occurred more frequently in males than in females. There were no differences in the iliac rotation parameters, but the ischium showed more external rotation in males (females 30° ± 2° versus males 24° ± 1°; p < 0.001). Regarding acetabular coverage, no differences between females and males were observed in the anterior acetabular sector angles. In contrast, males showed smaller values than females for the posterior acetabular sector angles (85° ± 9° versus 91° ± 7°; p = 0.002). In females, a correlation was observed between iliac rotation and acetabular sector angles (anterior acetabular sector angles: r = -0.35 [95% CI -0.05 to 0.16]; p < 0.001, posterior acetabular sector angles: r = 0.42 [95% CI 0.24 to 0.57]; p < 0.001). Similarly, ischial rotation showed a correlation with both acetabular sector angles (anterior acetabular sector angles: r = -0.34 [95% CI -0.51 to -0.15]; p < 0.001 and posterior acetabular sector angles: r = 0.45 [95% CI 0.27 to 0.59]; p < 0.001). Thus, in females, we observed that external iliac rotation and ischial internal rotation correlated with increased anterior acetabular coverage and reduced posterior coverage. In contrast, although acetabular coverage in males showed a correlation with iliac rotation (anterior acetabular sector angles: r = -0.55 [95% CI -0.78 to -0.18]; p = 0.006 and posterior acetabular sector angles: r = 0.74 [95% CI 0.48 to 0.88]; p < 0.001), no correlation was observed with ischial rotation. CONCLUSION: In males, acetabular retroversion occurs more commonly than in females and is attributed to their reduced posterior acetabular coverage. In females, an increase in the posterior acetabular coverage was correlated with the external rotation angle of the ischium, whereas in males, no correlation was found between ischial rotation and posterior acetabular coverage. In treating males with DDH via eccentric rotational acetabular osteotomy, it is essential to adjust bone fragments to prevent inadequate posterior acetabular coverage. Future studies might need to investigate the differences in acetabular coverage between males and females in various limb positions and consider the direction of bone fragment rotation. CLINICAL RELEVANCE: Our findings suggest that males with DDH exhibit acetabular retroversion more frequently than females, which is attributed to the reduced posterior acetabular coverage observed in males. The smaller posterior acetabular coverage in males might be related to differences in ischial morphology between sexes. During eccentric rotational acetabular osteotomy for males with DDH, adequately rotating acetabular bone fragments might be beneficial to compensate for deficient posterior acetabular coverage.

Association between advanced glycation end-products and fall risk in older adults: The Yakumo Study.

AIM: Advanced glycation end-products (AGEs) are irreversibly and heterogeneously formed compounds during the non-enzymatic modification of macromolecules, such as proteins. Aging and lifestyle habits, such as high-fat and high-protein diets, and smoking, promote AGEs accumulation. This study aimed to investigate the relationship between fall risk and AGEs in community-dwelling older adults. METHODS: This cross-sectional study included patients from the 2022 Yakumo Study who were evaluated for fall risk index 5-items version, locomotive syndrome stage and AGEs. AGEs were evaluated using Skin autofluorescence (SAF) measured by the AGE reader (DiagnOptics Technologies BV, Groningen, the Netherlands). We divided the participants into two groups according to the presence or absence of fall risk (fall risk index 5-items version ≥6 or not), and investigated the factors associated with fall risk. RESULTS: The fall risk group had a higher age and SAF, and a higher proportion of locomotive syndrome stage >2 than the without fall risk group in patients aged ≥65 years (P < 0.01). The multivariate logistic regression analysis after adjustment of age, sex and body mass index showed that locomotive syndrome stage ≥2 and SAF were independent associators of fall risk in older adults (odds ratio 3.26, P < 0.01, odds ratio 2.96, P < 0.05, respectively). The optimal cutoff value of the SAF for fall risk was 2.4 (area under the curve 0.631; 95% CI 0.53-0.733; sensitivity 0.415; specificity 0.814; P < 0.05). CONCLUSION: The accumulation of AGEs in skin tissues can be used to screen for fall risk comprehensively. Geriatr Gerontol Int 2024; 24: 517-522.

Long-term oral meclozine administration improves survival rate and spinal canal stenosis during postnatal growth in a mouse model of achondroplasia in both sexes.

Achondroplasia (ACH) is a skeletal dysplasia characterized by short-limbed short stature caused by the gain-of-function mutations in the fibroblast growth factor receptor 3 (FGFR3) gene. Activated FGFR3, which is a negative regulator of bone elongation, impairs the growth of long bones and the spinal arch by inhibiting chondrocyte proliferation and differentiation. Most patients with ACH have spinal canal stenosis in addition to short stature. Meclozine has been found to inhibit FGFR3 via drug repurposing. A 10-d treatment with meclozine promoted long-bone growth in a mouse model of ACH (Fgfr3ach mice). This study aimed to evaluate the effects of long-term meclozine administration on promoting bone growth and the spinal canal in Fgfr3ach mice. Meclozine (2 mg/kg/d) was orally administered to Fgfr3ach mice for 5 d per wk from the age of 7 d to 56 d. Meclozine (2 mg/kg/d) significantly reduced the rate of death or paralysis and improved the length of the body, cranium, and long bones in male and female Fgfr3ach mice. Micro-computed tomography analysis revealed that meclozine ameliorated kyphotic deformities and trabecular parameters, including BMD, bone volume/tissue volume, trabecular thickness, and trabecular number at distal femur of Fgfr3ach mice in both sexes. Histological analyses revealed that the hypertrophic zone in the growth plate was restored in Fgfr3ach mice following meclozine treatment, suggesting upregulation of endochondral ossification. Skeletal preparations demonstrated that meclozine restored the spinal canal diameter in Fgfr3ach mice in addition to improving the length of each bone. The 2 mg/kg/d dose of meclozine reduced the rate of spinal paralysis caused by spinal canal stenosis, maintained the growth plate structure, and recovered the bone quality and growth of axial and appendicular skeletons of Fgfr3ach mice in both sexes. Long-term meclozine administration has the potential to ameliorate spinal paralysis and bone growth in patients with ACH.

Association of mid-thigh quadriceps muscle quality with postoperative outcomes in patients with hip osteoarthritis undergoing total hip arthroplasty: a retrospective cohort study.

PURPOSE: Muscle quality is more important than muscle mass for assessing physical function. Computed tomography (CT) is used to evaluate intramuscular fatty infiltration. The mid-thigh quadriceps CT attenuation values (CTV) expressed in Hounsfield units (HU) negatively correlate with physical function. Patients with hip osteoarthritis (HOA) have lower extremity muscle atrophy, including decreased cross-sectional area (CSA), CTV, and muscle strength. Using preoperative CT images, we investigated the association between mid-thigh quadriceps CSA, CTV, and postoperative outcomes in patients with HOA. METHODS: This study included 62 patients who had unilateral HOA (62 hips) and underwent total hip arthroplasty (THA). We investigated the association between preoperative and postoperative Japanese Orthopaedic Association (JOA) hip scores, 12-item Short Form survey (SF-12), mid-thigh quadriceps CSA, and CTV. RESULTS: The mean age was 64.7 ± 10.1 years, with 15 men (24.2%), and the mean body mass index was 24.3 ± 4.3 kg/m2. Secondary HOA was present in 79.0% of patients. The mean CSA and CTV of the mid-thigh quadriceps on the operative side were 38.8 ± 9.8 cm2 and 40.3 ± 7.8 HU, respectively. Multiple regression analyses adjusted for age and sex showed that preoperative mid-thigh quadriceps CSA was not associated with preoperative and postoperative JOA hip scores or SF-12. The preoperative mid-thigh quadriceps CTV was associated with the postoperative JOA hip score in the gait ability domain and SF-12 in the physical component summary domain. CONCLUSION: Preoperative muscle quality is associated with postoperative outcomes in patients who have HOA regardless of age and sex.

Computer simulation study of cementless cup placement for dysplastic hip osteoarthritis using subluxation percentage of Crowe classification.

It is often difficult to achieve adequate bone coverage of the cup in total hip arthroplasty in cases of severe developmental dysplasia of the hip (DDH). This study aimed to evaluate the relationship between subluxation percentage of Crowe classification and cup center-edge (cup-CE) angle to investigate whether subluxation percentage according to the Crowe classification is a useful indicator for cementless cup placement. Cementless cup placement was simulated in 77 women with DDH in 91 hips (Crowe I, 35 hips; Crowe II, 35 hips; and Crowe III, 21 hips) using computed tomography-based computer simulation software. The cups were placed at the anatomic hip center (AHC) and 10-mm high hip center (HHC). The relationship between the subluxation percentage and cup-CE angle was evaluated using Spearman's rank correlation coefficient. In addition, the cutoff values for the subluxation percentage that satisfied a cup-CE angle ≥0° were determined using the receiving operating characteristic curve. The cup-CE angle was negatively correlated with the subluxation percentage in both AHC and 10-mm HHC (correlation coefficient ρ = -0.542 [p < 0.01] and -0.704 [p < 0.01], respectively). The cutoff values for subluxation percentage that satisfied a cup-CE angle ≥0° were 56.1% and 73.6% for AHC and 10-mm HHC, respectively. Cementless cup placement in AHC is difficult in cases with the subluxation percentage ≥56.1%, and HHC reconstruction or femoral structural autograft technique should be considered as an alternative. Moreover, placement at 10 mm above AHC is difficult in cases with subluxation percentage ≥73.6%.