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.

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.

Phase 1b study on the repurposing of meclizine hydrochloride for children with achondroplasia.

Achondroplasia (ACH) is a common skeletal dysplasia characterized by a disproportionately short stature. We found that meclizine, which is an over-the-counter drug for motion sickness, inhibited the fibroblast growth factor receptor 3 (FGFR3) gene using a drug repositioning strategy, and meclizine 1 and 2 mg/kg/day promoted bone growth in a mouse model of ACH. A previous phase 1a clinical trial for children with ACH demonstrated that a single dose of meclizine 25 and 50 mg was safe and that the simulated plasma concentration achieved steady state approximately 10 days after the first dose. The current study aimed to evaluate the safety and pharmacokinetics (PK) of meclizine in children with ACH after a 14-day-repeated dose of meclizine. Twelve patients with ACH aged 5-10 years were enrolled. Meclizine 12.5 (cohort 1) and 25 mg/day (cohort 2) were administered after meals for 14 days, and adverse events (AEs) and PK were evaluated. No patient experienced serious AEs in either group. The average (95% confidential interval [CI]) maximum drug concentration (Cmax), peak drug concentration (Tmax), area under the curve (AUC) from 0 to 24 h, and terminal elimination half-life (t1/2) after a 14-day-repeated administration of meclizine (12.5 mg) were 167 (83-250) ng/mL, 3.7 (3.1-4.2) h, 1170 (765-1570) ng·h/mL, and 7.4 (6.7-8.0) h, respectively. The AUC0-6h after the final administration was 1.5 times that after the initial dose. Cmax and AUC were higher in cohort 2 than in cohort 1 in a dose-dependent manner. Regarding the regimen of meclizine 12.5 and 25 mg in patients < 20 kg and ≥ 20 kg, respectively, the average (95% CI) AUC0-24h was 1270 (1100-1440) ng·h/mL. Compartment models demonstrated that the plasma concentration of meclizine achieved at a steady state after the 14th administration. Long-term administration of meclizine 12.5 or 25 mg/day is recommended for phase 2 clinical trials in children with ACH.

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.

Differences in peri-hip articular pain after total hip arthroplasty between taper wedge stem and fit-and-fill stem.

Background: Total hip arthroplasty (THA) for hip disorders helps to alleviate pain and improve active daily life. When determining the effects of medical therapy and the subsequent clinical results, patient quality of life (QOL) also needs to be assessed. Recently, patient-reported outcomes (PRO) have become important as evaluation criteria. This study aimed to evaluate patient QOL and various PRO between different types of cementless stems and to clarify the relationship between PRO and stem-cortical bone contact. Methods: The study comprised 138 consecutive patients undergoing cementless THA for hip osteoarthritis. We assessed three different types of PRO: the Japanese Orthopaedic Association Hip-Disease Evaluation Questionnaire (JHEQ), patient's joint perception, and peri-hip articular joint pain (PHAP). We measured the state of contact between femur and implant by density mapping. Results: No significant difference was noted in PRO between stem types based on the JHEQ and patient's joint perception. PHAP occurred more frequently in the patients with a taper wedge stem versus a fit-and-fill stem. In both groups, distal contact was associated with PHAP but not with JHEQ results and patient's joint perception. Conclusion: The difference in PHAP between the two stem types groups was significant, with postoperative PHAP being higher with the taper wedge stem because of the more distal contact between the taper wedge stem and femur cortical bone.

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.

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.

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.

Meclozine Attenuates the MARK Pathway in Mammalian Chondrocytes and Ameliorates FGF2-Induced Bone Hyperossification in Larval Zebrafish.

Meclozine has been developed as an inhibitor of fibroblast growth factor receptor 3 (FGFR3) to treat achondroplasia (ACH). Extracellular signal regulated kinase (ERK) phosphorylation was attenuated by meclozine in FGF2-treated chondrocyte cell line, but the site of its action has not been elucidated. Although orally administered meclozine promoted longitudinal bone growth in a mouse model of ACH, its effect on craniofacial bone development during the early stage remains unknown. Herein, RNA-sequencing analysis was performed using murine chondrocytes from FGF2-treated cultured tibiae, which was significantly elongated by meclozine treatment. Gene set enrichment analysis demonstrated that FGF2 significantly increased the enrichment score of mitogen-activated protein kinase (MAPK) family signaling cascades in chondrocytes; however, meclozine reduced this enrichment. Next, we administered meclozine to FGF2-treated larval zebrafish from 8 h post-fertilization (hpf). We observed that FGF2 significantly increased the number of ossified vertebrae in larval zebrafish at 7 days post-fertilization (dpf), while meclozine delayed vertebral ossification in FGF2-induced zebrafish. Meclozine also reversed the FGF2-induced upregulation of ossified craniofacial bone area, including ceratohyal, hyomandibular, and quadrate. The current study provided additional evidence regarding the inhibitory effect of meclozine on the FGF2-induced upregulation of MAPK signaling in chondrocytes and FGF2-induced development of craniofacial and vertebral bones.

The effects of patient characteristics and stem alignment on distal femoral cortical hypertrophy after cemented polished tapered stem implantation.

BACKGROUND: The objective of this study was to evaluate the results of over 10 years of total hip arthroplasty (THA) practice with ExeterTM stems and the clinical relevance of distal femoral cortical hypertrophy (DFCH). METHODS: We retrospectively reviewed 127 hips (120 patients) that had undergone THA with ExeterTM stems between 2004 and 2007. Kaplan-Meier survival analyses for the stem of all 127 hips were performed using different endpoints. Of 127 hips, 100 (94 patients) had complete 10-year follow-up data, including the Japanese Orthopaedic Association Hip Disease Evaluation Questionnaire (JHEQ) as the patient-reported outcomes, and the clinical relevance of DFCH was analyzed using multivariable logistic regression analysis. RESULTS: The survival of the stem with the endpoint of re-operation for loosening, > 5-mm subsidence, and re-operation for any reason were 100%, 99.1% (95% CI 97.5-100%), and 98.3% (95% CI 96.0-100%), respectively. Of 100 hips followed completely for 10 years, DFCH occurred in 20 hips (20%). The satisfaction and pain visual analog scale of JHEQ revealed high satisfaction and less pain in patients with DFCH. By multivariate logistic regression analysis, body weight > 55 kg (odds ratio: 2.88, p = 0.035) and varus stem alignment (odds ratio: 6.56, p = 0.003) were found to be predictors for DFCH. CONCLUSIONS: The incidence of DFCH with the ExeterTM stem was 20%. A body weight > 55 kg and varus stem alignment are predictors for future DFCH. DFCH with the ExeterTM stem indicates a good outcome with less hip pain.

Peri-prosthetic bone remodeling and change in bone mineral density in the femur after cemented polished tapered stem implantation.

OBJECTIVE: We examined longitudinal changes in bone mineral density (BMD) around the femur for 5 years after total hip arthroplasty (THA) using cemented collarless polished double-tapered stem implantation and investigated the influence of BMD changes on radiological remodeling of the femur. MATERIALS AND METHODS: Sixty hips from 56 patients who underwent cemented THA with a collarless polished double-tapered stem were included. BMD was measured 2 weeks postoperatively (baseline), 3 months, 6 months, 1 year and annually thereafter until 5 years after surgery using dual-energy X-ray absorptiometry on the lumbar spine and proximal femur of the operated side according to the Gruen's zone classification. We analyzed predictable factors for BMD preservation in the proximal femur and compared radiological remodeling of the femur and changes in BMD. RESULTS: BMD at 5 years in zone 7 decreased less than 10%, whereas BMD in zone 1 increased to over the baseline (+ 1.9%). Multiple linear regression analyses revealed that body weight was a predictor for positive BMD change in the proximal femur. The frequency of radiolucency of the femur was significantly lower in patients who exhibited an increase in BMD at 5 years compared with BMD at 2 weeks in zone 7. CONCLUSION: BMD preservation of the proximal femur after cemented collarless polished double-tapered stem implantation was more effective in heavier patients. Furthermore, the frequency of radiolucency around the stem was significantly lower in patients who exceeded 100% of the baseline BMD in zone 7 at 5 years.

Favorable Results of Primary Total Hip Arthroplasty With Acetabular Impaction Bone Grafting for Large Segmental Bone Defects in Dysplastic Hips.

BACKGROUND: The aim of the present study was to assess midterm results after acetabular impaction bone grafting (IBG) in primary total hip arthroplasty (THA) for developmental dysplasia of the hip (DDH) with large acetabular segmental defect. METHODS: Primary THA with IBG for DDH with large acetabular segmental defect was performed in 40 hips of 38 patients. The average age was 61.6 years (range: 33-82 years), and the average follow-up period was 7.5 years (range: 3-10.3 years). The Merle d'Aubigné and Postel hip score and complications were assessed. For radiological assessment, postoperative location of the hip rotation center, the socket inclination angle, and the socket center-edge angle were assessed. Kaplan-Meier survival analysis was performed with the end points of any type of reoperation and aseptic acetabular loosening. RESULTS: The mean Merle d'Aubigné and Postel hip score improved from 10.4 points to 16.2 points at the final follow-up. Reoperation was performed in 1 case for acute infection without loosening. In 39 out of 40 hips (97.5%), the center of hip rotation was located beneath the "high hip center." The average socket inclination angle was 39.3° (range: 30°-54°), and the average socket center-edge angle was -11.8° (range: -23° to 9°). Survival rate of acetabular component at 8 years with the end point of any reoperation and of aseptic loosening was 96.6% (95% confidence interval: 89.9%-100%) and 100%, respectively. CONCLUSION: Acetabular IBG represents one of the useful options for restoring a normal hip center and acetabular bone stock in primary THA for DDH with large acetabular defect.