2026年8月 保髋进展 JCR Q2

BACKGROUND: This retrospective study aimed to characterize the clinical, radiographic, and biochemical outcomes of surgical hip dislocation (SHD) combined with intralesional curettage and bone grafting for the treatment of phosphaturic mesenchymal tumors (PMT) of the femoral head and neck.

METHODS: A total of 7 patients with PMT of the femoral head and neck confirmed by pathology (mean lesion length 18.8 mm) were treated in our hospital between January 2018 and December 2023. All patients underwent SHD combined with tumor curettage and bone grafting. Preoperative and postoperative assessments included radiographs/MRI for union, recurrence, avascular necrosis (Steinberg grade), secondary osteoarthritis (Tönnis grade), and clinical outcomes by visual analog scale (VAS), Musculoskeletal Tumor Society scoring system (MSTS) and modified Harris Hip Score (mHHS).

RESULTS: All patients underwent SHD with intralesional curettage and bone grafting. Over a mean 42-month follow-up, no local recurrence or distant metastasis occurred. All graft sites achieved radiographic union. The Tönnis grade remained unchanged in six patients, whereas one patient showed progression from grade 1 to grade 2. The same patient also showed progression of femoral head osteonecrosis from Steinberg stage 0 to stage I. Pain and functional scores improved at the final follow-up: median VAS decreased from 4.0 to 1.0, median MSTS increased from 18.0 to 27.0, and median mHHS improved from 75.0 to 85.0. Serum phosphate levels improved postoperatively and normalized during follow-up.

CONCLUSION: SHD combined with intralesional curettage and bone grafting may represent a viable hip-preserving treatment option for patients with PMT involving the femoral head and neck. However, these findings warrant further validation in larger cohorts with longer follow-up periods.

INTRODUCTION: Although pelvic landmarks have traditionally been used to estimate the femoral head center (FC), their reliability may be limited in patients with developmental dysplasia of the hip (DDH). In contrast, femoral-based reference methods have been insufficiently investigated. This study aimed to evaluate the feasibility and clinical utility of estimating the FC location in DDH using a three-dimensional model derived from trochanteric landmarks.

METHODS: We retrospectively analyzed 128 femurs from 84 female patients with DDH (mean age, 36.9 years) who underwent curved periacetabular osteotomy (CPO) from April 1, 2010, to September 30, 2020, and had no symptoms involving the spine or knee. The FC was estimated using multiple regression models based on the three-dimensional coordinates (x, y, and z) of the greater and lesser trochanter tips. Differences between the estimated and actual FC positions were assessed along all three axes.

RESULTS: Correlation coefficients between the estimated and actual FC ranged from 0.725 to 0.875 across the three directions. The mean absolute error was 2-3 mm, with greater errors observed in the anteroposterior direction than in the craniocaudal direction. An estimation error within 3 mm may be considered relatively small in the context of clinically acceptable ranges reported in previous studies for restoring femoral offset and leg length during total hip arthroplasty (THA), supporting the practical applicability of this method in preoperative planning.

CONCLUSION: The accuracy of the present approach was comparable to that reported in healthy populations and exceeded that of previous pelvic landmark-based regression techniques. This trochanter-based three-dimensional method enables clinically acceptable estimation of the FC in patients with DDH and may serve as a useful adjunct for planning of the femoral component when the native FC is difficult to identify.

BACKGROUND: The International Hip Outcome Tool 12 (iHOT-12) is commonly utilized to track outcomes in individuals with acetabular dysplasia (AD). Clinically important outcome values (CIOVs) of the iHOT-12 in individuals with AD are not yet defined.

PURPOSE: To define the minimal clinically important difference (MCID), patient acceptable symptom state (PASS) change score, absolute PASS threshold, and maximal outcome improvement (MOI) value for the iHOT-12 in individuals undergoing physiotherapy (PT) for AD.

STUDY DESIGN: Prospective cohort; psychometric property analysis.

METHODS: This prospective study included individuals aged 10-35 years with a clinical and radiographic diagnosis of AD who were referred for conservative management at two centers between December 2023 and February 2025. At baseline assessment and after 8-10 weeks of PT, individuals completed the iHOT-12. At 8-10-week follow-up, individuals also completed three anchor questions on satisfaction and function. The MCID was calculated utilizing 0.5 times the standard deviation of baseline iHOT-12 scores. Receiver operator curve analysis was utilized to determine the PASS change score, absolute PASS threshold, and MOI value.

RESULTS: Forty-five patients (42 females, mean age 16.5 + 7.8) met the inclusion criteria. After 8-10 weeks of PT (mean follow-up time = 69 days), 25 (55.6%) participants were in the "improved" group and 20 (44.4%) were in the "not improved" group. The MCID was 8.5 points. A PASS change score of 15.2 was calculated for individuals who were satisfied with high sensitivity (.77) and specificity (.78) with an AUC = .76 (95% CI: .59-.93). An absolute PASS iHOT-12 threshold score of 62 (sensitivity = .62, specificity = .87) identified those who were satisfied with their hip function after a trial of PT with an AUC = .82 (95% CI: .67-.97). An MOI threshold of 22.9% was also calculated with high sensitivity (.69) and specificity (.88) with an AUC = .78 (95% CI: .61-.95).

CONCLUSION: This study defines MCID, PASS change score, absolute PASS threshold, and MOI threshold for the iHOT-12 in patients with AD after 8-10 weeks of PT. While most individuals reported improvement in symptoms, only half of individuals were satisfied with their current level of function.

LEVEL OF EVIDENCE: Level 2.

PURPOSE: Dynamic hip distractibility is an intraoperative marker of hip microinstability; however, a quantitative assessment in the outpatient setting has not been established. This study aimed to quantify hip distractibility using traction arthrography in patients with early hip disorders and to identify clinical and radiographic factors associated with increased distractibility.

METHODS: We retrospectively reviewed 84 patients (84 hips) with early hip disorders who underwent traction arthrography, including frank dysplasia (30 hips), borderline hip dysplasia (21 hips), labral tear (14 hips), and femoroacetabular impingement (19 hips). Fluoroscopic arthrograms were obtained during manual hip distraction, and the joint distraction width (JDW) was measured. JDW distribution was examined to determine a threshold for increased distractibility. Multivariable logistic regression was used to identify factors associated with increased distractibility.

RESULTS: JDW ranged from 0.0 mm to 12.2 mm, with a median value of 3.7 mm. Based on the bimodal distribution of JDW, increased distractibility was defined as JDW ≥ 3.0 mm and was identified in 45 hips (54%). Multivariable analysis identified Beighton score ≥ 4 (odds ratio [OR] 3.13, p = 0.046), upsloping lateral sourcil (OR 6.45, p = 0.001), and Shenton line breakage (OR 5.34, p = 0.016) as independent factors associated with increased distractibility.

CONCLUSION: Traction arthrography enables quantitative assessment of dynamic hip distractibility in the outpatient setting and may provide a practical adjunct for assessing instability-related pathology in early hip disorders.

PURPOSE: The role of periacetabular osteotomy (PAO) in symptomatic borderline hip dysplasia (borderline HD) remains controversial because the lateral centre-edge angle may not reflect global dysplastic morphology. We examined whether selected borderline dysplastic hips showed additional dysplastic features and compared mid- to long-term outcomes with frank hip dysplasia (frank HD).

METHODS: This retrospective comparative cohort study included 33 patients (35 hips) with borderline HD (18° ≤ lateral centre-edge angle < 25°) and 319 patients (357 hips) with frank HD (lateral centre-edge angle < 18°) treated with PAO from 1996 to 2009. Radiographic morphology, Kaplan-Meier total hip arthroplasty-free survival, and patient-reported outcome measures (PROMs) after 1:3 propensity score matching were analysed.

RESULTS: In the borderline HD cohort, 33 hips (94.3%) met at least one frank HD criterion other than lateral centre-edge angle and 12 hips (34.3%) met three or more. Mean follow-up was 14.0 years in the borderline HD cohort and 13.9 years in the frank HD cohort. One borderline dysplastic hip and 50 frank dysplastic hips underwent total hip arthroplasty. The 20-year survival rate was 90.0% in borderline HD and 78.8% in frank HD (log-rank p = 0.101). Matched PROMs did not differ significantly between groups.

CONCLUSION: Borderline dysplastic hips selected for PAO usually showed multidirectional dysplastic morphology resembling frank HD. In carefully selected symptomatic borderline HD, PAO was associated with favourable long-term survival and PROMs comparable with frank HD.

PURPOSE: This study aimed to identify morphological differences between the symptomatic and asymptomatic hips in patients with bilateral hip dysplasia (HD).

METHODS: From 109 patients who underwent eccentric rotational acetabular osteotomy (ERAO) between 2017 and 2022, 33 patients were selected as the First Cohort. These patients had undergone ERAO on the symptomatic side, while the contralateral side remained completely asymptomatic for ≥ three years postoperatively. Among them, 18 patients with matching lateral centre-edge angles (CEA) on both sides were selected as the Second Cohort. The acetabular sector angles (ASAs) were measured three-dimensionally. Femoral neck anteversion (FNA) and femoral head lateralization were also assessed. Morphological comparisons between the symptomatic and asymptomatic sides were conducted using paired t-tests in both cohorts. In the Second Cohort, conditional logistic regression analysis was used to identify factors associated with the onset of hip pain.

RESULTS: In the First Cohort, the symptomatic side exhibited lower ASAs across the superior-to-anterior acetabulum than the asymptomatic side, whereas no significant differences in ASAs were observed in the Second Cohort. By contrast, both cohorts exhibited greater FNA and lateralization on the symptomatic side. Conditional logistic regression analysis in the Second Cohort identified increased FNA (odds ratio: 1.3) and lateralization (odds ratio: 4.6) as factors associated with hip pain (all p < 0.05).

CONCLUSION: When the CEA is comparable on both sides in patients with bilateral HD, morphological features, such as increased FNA and femoral head lateralization, may be more indicative of the symptomatic hip than acetabular parameters.

PURPOSE: To review Japan's major contributions to hip joint preservation and reconstruction, spanning joint-preservingosteotomy, biomaterials innovation, and computer-assisted precision arthroplasty.

METHODS: A narrative review was performed to summarize landmark clinical and scientific advances originating from Japan in the management of osteonecrosis of the femoral head (ONFH), developmental dysplasia of the hip (DDH), total hiparthroplasty (THA), bearing surface technology, and computer-assisted surgery.

RESULTS: Japanese research has advanced the understanding and treatment of ONFH through nationwide epidemiological studies, development of classification systems, clarification of steroid-associated pathophysiology, and long-term validation of joint-preserving procedures, particularly transtrochanteric rotational osteotomy. In DDH, Japanese surgeons refined reconstructive osteotomies and established surgical strategies for complex primary and high-dislocation THA. Early clinical adoption of highly cross-linked polyethylene and advances in ceramic bearing technology improved implant longevity by reducing wear and osteolysis. Japan also pioneered CT-based navigation for both acetabular and femoral component placement and introduced the functional pelvic plane concept, shifting implant alignment from fixed safe zones toward individualized functional positioning that incorporates stem anteversion and spinopelvic dynamics. These innovations have subsequently expanded to robotic-assisted surgery and advanced three-dimensional reconstruction.

CONCLUSION: Japan has made substantial contributions to modern hip surgery, from biological joint preservation to precision arthroplasty. This integrated approach-emphasizing anatomical accuracy, biomechanical restoration, and long-term durability-continues to influence contemporary practice and provides a foundation for future advances in robotics, artificial intelligence, and personalized hip reconstruction.

BACKGROUND: Congenital femoral deficiency (CFD) has many anatomical variations. A management-oriented classification offers greater clinical value. The SUPERhip reconstruction procedure was developed based on Paley's classification, though reports on its outcome remain limited.

PURPOSE: Our aim in this study was to evaluate the radiographic and range of motion outcomes after hip reconstruction in CFD using the SUPERhip technique.

METHODS: This is a prospective case series that included 12 patients with unilateral CFD type one who underwent hip reconstruction using the SUPERhip 1 procedure, with at least a three-year follow-up. Bilateral cases, neck pseudarthrosis, diaphyseal deficiency, and cases with previous hip surgery were excluded. Average follow-up was 41.5 months. Radiographs were used for evaluation of the neck shaft angle (NSA), acetabular index (AI), and lateral centre edge angle. Range of motion (ROM) was evaluated using Children's Hospital Oakland Hip Evaluation Scale (CHOES). Non-parametric tests were used for statistical analysis.

RESULTS: The postoperative range of motion scores were excellent in four cases, good in seven cases, and fair in one case. Eight cases underwent pelvic osteotomy, post-operative AI and LCEA were within the accepted degrees for all cases. Neck shaft angle regressed toward varus in four cases (average 13°) after plate removal. One case developed a deep infection requiring debridement. Persistent hip flexion was present in two cases (15°, 25°). Five cases underwent lengthening; no hip dislocations or changes in AI or LCEA were encountered during or after lengthening. Age, sex, and CFD type did not influence the final clinical outcome or the varus recurrence.

CONCLUSION: The radiographic outcome and range of motion after the SUPERhip 1 technique for type 1 CFD yielded good to excellent results in 91.6%. The procedure was found to be reliable and reproducible with an acceptable complication rate. The varus recurrence remains a problem.

BACKGROUND: Hip dysplasia and secondary hip osteoarthritis are common in Asian populations, and are major causes of hip arthroplasty. Periacetabular osteotomy (PAO) is a joint-preserving surgical option for young patients with symptomatic hip dysplasia, aimed at preventing progression to end-stage arthritis. This study aimed to analyze the ten year trends in hip dysplasia diagnosis and PAO utilization in South Korea using national health insurance claims data.

MATERIALS AND METHODS: This nationwide retrospective study analyzed data from the Health Insurance Review & Assessment Service (HIRA) covering 10-year period (2014-2023). The diagnostic trend of hip dysplasia was investigated alongside the trends in PAO surgeries. Population-based PAO rates were examined as the primary analysis, while PAO frequency relative to the cumulative number of diagnosed cases was additionally assessed as a secondary analysis, along with regional distributions and trends across age groups.

RESULTS: Over the ten year period, a total of 48,890 patients (63.7% female) were diagnosed with hip dysplasia, and 419 hips underwent PAO in patients aged ten years or older. The population-based PAO rate remained low throughout the study period, increasing from 0.049 per 100,000 population in 2014 to a peak of 0.115 in 2020, decreasing to 0.084 in 2021, and then stabilizing at approximately 0.088 in 2022-2023. In terms of hospital regional distribution, 155 out of 419 cases (37.0%) were performed in Seoul, followed by Jeonbuk Province with 148 cases (35.3%). By age group, the highest number of surgeries was performed in patients aged ten to 19 years (140/419 cases, 33.4%).

CONCLUSION: In South Korea, the population-based utilization of PAO remained low over the past decade despite a statistically significant increasing trend, and lagged behind the level reported in other countries. Whether this pattern reflects underuse of PAO, appropriate patient selection, or a shift toward alternative treatments cannot be determined from administrative claims data alone.

INTRODUCTION: Hip resurfacing arthroplasty (HRA) is a bone-preserving option for young, active patients. The influence of the underlying diagnosis on long-term outcome remains unclear, particularly the distinction between primary osteoarthritis (OA), developmental dysplasia of the hip (DDH) and non-OA conditions.

MATERIALS AND METHODS: We retrospectively reviewed 104 consecutive metal-on-metal HRAs in 101 patients (three bilateral) performed by one surgeon between 2006 and 2011, stratified into Primary OA (n = 50), DDH (n = 29) and Non-OA (n = 25: avascular necrosis [AVN] n = 15, inflammatory arthritis n = 5, post-traumatic arthritis n = 3, Legg-Calvé-Perthes disease n = 2). AVN was analysed additionally as an independent group, and exploratory analyses restricted to female patients and to cups ≤ 50 mm addressed the collinearity of dysplasia, sex and size. Survivorship used Kaplan-Meier estimation with revision as the endpoint.

RESULTS: Implant status was known for all 104 hips; the 91 unrevised assessed hips had a mean follow-up of 16.2 ± 1.5 years. Overall 15-year survivorship was 95.2%. Primary OA, Non-OA and AVN each showed 100%; DDH 82.8% (versus Primary OA p = 0.002, versus Non-OA p = 0.031). All five revisions occurred in female DDH patients with a cup ≤ 50 mm; DDH survivorship remained lower within female patients (p = 0.025) and within small cups (p = 0.006), with no event in any comparator arm. Final HHS was lower in DDH (89.5 ± 8.5) than in Primary OA (93.9 ± 6.8) or Non-OA (95.0 ± 4.9; p = 0.012), a difference below the minimal clinically important improvement threshold of 15.9 to 18 points. The Co/Cr ratio did not differ between groups (p = 0.37).

CONCLUSIONS: HRA achieved 100% 15-year survivorship in primary OA and in non-OA diagnoses including AVN. Dysplasia may be associated with an increased risk of revision, but dysplasia, female sex and small component size were too collinear, with no revision outside the dysplastic group, for their independent contributions to be separated.

PURPOSE: This systematic review evaluates the reported incidence of late-developing acetabular dysplasia in infants with breech presentation or a positive family history of developmental dysplasia of the hip following normal early ultrasound.

METHODS: MEDLINE, Embase, and the Cochrane Library were searched for studies of breech or positive family-history cohorts who underwent early ultrasound and subsequent radiographic follow-up for late-developing acetabular dysplasia. Two reviewers independently screened studies, extracted data, and assessed methodological quality.

RESULTS: Ten studies met inclusion criteria. Across these studies, radiographic follow-up after normal infant ultrasound was incomplete and variably reported, with several cohorts demonstrating substantial attrition. Among infants with a positive family history who underwent radiographic assessment (n = 520), no cases of late-developing acetabular dysplasia were reported. In breech cohorts with available follow-up (n = 727), reported late-developing acetabular dysplasia rates ranged from 0% to 29%, with higher estimates generally observed in studies with earlier follow-up or more permissive diagnostic thresholds. Management was predominantly observational, and operative treatment was described in one case only.

CONCLUSIONS: Persistent acetabular dysplasia after a normal screening ultrasound was not identified in the included family-history cohorts with post-screening imaging. In breech cohorts, reported rates of late-developing acetabular dysplasia vary widely and appear to be influenced by timing of assessment and diagnostic criteria. Methodological heterogeneity and incomplete cohort ascertainment limit interpretation, underscoring the need for prospective studies with standardised definitions and child-level incidence reporting.

SIGNIFICANCE OF STUDY: This review highlights critical gaps in the evidence informing management of developemental dysplaisa of the hip following screening and provides a framework for designing definitive prospective studies to guide surveillance practices.

LEVEL OF EVIDENCE: Level III.

PURPOSE: It was aimed to evaluate publication trends, scientific impact, and collaboration patterns in developmental dysplasia of the hip (DDH) research.

METHODS: DDH-related publications indexed in the Web of Science database between January 1, 2000, and December 31, 2025, were analyzed. Publication output, citation metrics, author and institutional collaboration networks, leading journals, and major research themes were assessed.

RESULTS: A total of 3462 articles were identified. Annual publication output increased substantially over the study period. The most cited article, by Steppacher et al., reported long-term outcomes of periacetabular osteotomy. Sankar WN (USA) was the most prolific author, while Clohisy JC (USA) had the highest citation impact and h-index. Shanghai Jiao Tong University (China) produced the greatest number of publications, whereas Western institutions achieved higher citation impact despite lower publication volumes. The USA led in publication output, while Switzerland demonstrated the highest citation impact. North American authors and institutions showed the strongest international collaboration rates, with the USA occupying the central position in the global collaboration network. The Journal of Pediatric Orthopaedics published the largest number of DDH-related articles. Research themes exhibited notable geographical variation.

CONCLUSION: DDH research has grown rapidly over the past 25 years. North American and Western European researchers have played a leading role through strong international collaborations and publication in high-impact journals. Publication quality and global partnerships appear to be key determinants of scientific influence in the field.

SIGNIFICANCE OF THE STUDY: This study provides novel bibliometric insights into the current landscape of DDH research for trainees, researchers, clinicians, and policymakers.