2026年6月 保髋进展 JCR Q1

OBJECTIVE: Femoroacetabular impingement (FAI) and synovitis have been recognized as essential factors for developing osteoarthritis (OA) in the hip joints. However, little is known about altered synovial cellular compositions, their associated transcriptomic profiles, and cell-cell interactions in FAI and hip OA.

METHODS: Synovial samples from a sex-matched cohort of patients with FAI and hip OA (n = 6 per condition) were analyzed using integrative single-cell RNA sequencing and spatial transcriptomics.

RESULTS: Compared to FAI, epiregulin (EREG)-enriched lining synovial fibroblast-like synoviocytes (FLS) were significantly increased in hip OA. EREG+ FLS are proinflammatory due to elevated expression of CXCL1, IL8, and MMPs. Pseudotime analysis predicts that EREG+ FLS are derived from DPP4+PI16+ sublining FLS, likely regulated by NFIX and REL, as well as ELK3 and ETV6 transcription factors under FAI or OA conditions, respectively. Importantly, the only putative cell-cell interaction is fibroblast growth factor 2 (FGF2)-syndecan 4 (SDC4) communication between COL1A1+IGFBP5+ fibrotic macrophages and EREG+ FLS. This interaction may induce expression of interleukin (IL)-6, IL-8, and matrix metalloproteinase 1 (MMP1) in hip OA synovium. The Gene Ontology analysis of activated genes downstream of FGF2-SDC4 signaling revealed that inflammation and angiogenesis were up-regulated in hip OA, whereas positive gene transcription and skeletal muscle differentiation were dominant in FAI. Moreover, we also found that EREG+CCL20+MMP3hi lining FLS along with most macrophage and monocyte populations are unique to patients with hip OA compared to patients with knee OA and rheumatoid arthritis.

CONCLUSION: The findings of this study offer a groundwork in tailoring novel targets and therapies for patients with FAI and hip OA.

PURPOSES: To compare minimum 2-year patient-reported outcomes measures (PROMs) between adolescents undergoing primary and revision hip arthroscopy.

METHODS: Data were prospectively collected and retrospectively reviewed for adolescents who underwent revision hip arthroscopy from November 2008 and November 2021. Patients with baseline and minimum 2-year PROMs were included. Exclusion criteria were patients over 19 years old or dysplastic. A propensity-matched comparison was performed to a primary control group in a 1:2 ratio based on age at surgery, sex, body mass index, and acetabular Outerbridge grade. PROMs, clinical benefit achievement rates, and secondary surgeries were reported and compared.

RESULTS: Thirty-five adolescents (37 revisions hips) were included and propensity-matched. Significant improvement was noted for modified Harris Hip Score, Non-Arthritic Hip Score, Hip Outcome Score Sport-Specific Subscale, International Hip Outcome Tool, patient satisfaction, and visual analog scale for pain in both groups (P < .01). The revision group had significantly lower postoperative values for all the PROMs (P < .01); however, improvement (delta value) was similar. Revision hips underwent secondary arthroscopy at higher rates when compared with primary hips (21.6% vs 5.4%; P < .05) and were 4.83 times as likely to receive an additional rerevision surgery.

CONCLUSIONS: Adolescents undergoing revision arthroscopy showed significant improvement in all PROMs (modified Harris Hip Score, Non-Arthritic Hip Score, Hip Outcome Score Sport-Specific Subscale, International Hip Outcome Tool, and visual analog scale for pain) at a minimum 2-year follow-up. When compared with a propensity-matched primary control group, revision hips had lower preoperative and postoperative values, but similar improvement magnitude for all PROMs, but met clinically meaningful thresholds at lower rates, and were 4.83 times more likely to require a subsequent hip arthroscopy.

LEVEL OF EVIDENCE: Level III, retrospective comparative study.

PURPOSE: To provide an updated review of return-to-sport rates and outcomes for elite athletes undergoing hip arthroscopy and to discuss the impact of varying definitions of return to sport in the current literature.

METHODS: A systematic review of the literature was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Included studies reported a return-to-sport rate for elite athletes undergoing hip arthroscopy for treatment of femoroacetabular impingement and/or labral tears. Only elite athletes, defined as those competing at the Olympic, national, professional, semiprofessional, or collegiate levels, were included. Extracted data included patient demographic data, sports played, level of competition, return-to-sport rates, time to return to sport, patient-reported outcomes, intraoperative findings, surgical interventions, and radiological data.

RESULTS: A total of 1406 patients and 1548 hips across 21 studies were included in this analysis. Included studies had mean ages at the time of surgery ranging from 19.5 to 38 years. The proportion of male athletes varied from 42% to 100%, and body mass indices ranged from 22.9 to 31.4 kg/m2. A total of 18 studies reported a return-to-sport rate where return was specifically defined as a return to the same level of competition, with rates ranging from 25% to 100%. Nine studies included a broader definition of return to sport, with rates ranging from 67% to 100%. Mean time to return to sport across studies ranged from 4.2 to 10.8 months, and mean follow-up periods ranged from 12.3 to 92.4 months.

CONCLUSIONS: Reported return-to-sport rates for elite athletes undergoing hip arthroscopy were high. However, there exists much variability in the characterizations of return to sport, which results in inconsistent return rates that must be contextualized for patients and surgeons to make informed decisions.

LEVEL OF EVIDENCE: Level IV, systematic review of Level III and IV studies.

PURPOSE: To examine the relationship between radiographic signs of acetabular retroversion (AR) in symptomatic femoroacetabular impingement syndrome (FAIS) patients and global AR (GAR) measured on 3-dimensional imaging.

METHODS: A retrospective cohort study was conducted to identify patients between 2017 and 2024, with radiographic and clinical FAIS. Standardized pelvic radiographs were analyzed for crossover sign (COS; including crossover percentage), ischial spine sign (ISS), and posterior wall sign (PWS). Alpha angle, femoral torsion, lateral center-edge angle (LCEA), and acetabular version at 1, 2, and 3 o'clock were collected from computed tomography (CT) scans. Patients with AR, defined as >/=5° of retroversion relative to normal values at the 1, 2, and 3 o'clock positions were identified. The sensitivity and specificity of each sign were calculated using CT scans to establish groups of focal and GAR. Continuous variables were compared using one-way analysis of variance and linear regression analyses.

RESULTS: Of the 273 cases, 209 were included. Patients were categorized into the following groups: globally retroverted (n = 56), focally retroverted (n = 74), and normal version (n = 79). The GAR minimal clinically important difference (MCID) is .086°, focal AR MCID is .062°, and normal range acetabular version is .063°. COS and PWS were most sensitive at detecting CT-confirmed AR at 91.6%. Combined crossover percentage greater than 30%, with all positive plain X-ray signs of AR, was most specific at 94.6%. A significant association between crossover percentage and extent of AR at the 3 o'clock position was observed (R2 = .1008, P = .0003). Gender-based sensitivity and specific analyses show COS and PWS are most sensitive, and an isolated COS% greater than 30% is most specific at detecting GAR in male patients. A positive ISS was more prevalent among females, whereas a positive PWS was more prevalent among males.

CONCLUSIONS: This retrospective review of patients with symptomatic FAIS and radiographic signs of FAI accurately detects GAR with high sensitivity and specificity without a CT scan. Crossover percentage was associated with the extent of AR and may be valuable as a predictive tool. This may help identify patients with more complex deformities that may benefit from CT imaging.

LEVEL OF EVIDENCE: Level III, retrospective diagnostic case series.

OBJECTIVES: To (1) examine the prevalence of cam and pincer morphologies in adolescent (ages 10-19 years) and young adult (ages 20-35 years) athletes, and (2) summarize diagnostic imaging and clinical assessment methods associated with femoroacetabular impingement (FAI) syndrome. DESIGN: Epidemiology systematic review with meta-analysis. LITERATURE SEARCH: The MEDLINE, Embase, SPORTDiscus, CINAHL, and Scopus databases were searched to February 2025. STUDY SELECTION CRITERIA: English studies reporting on prevalence of FAI syndrome morphologies, whether symptomatic or not, in male/female athletes (10-35 years) were eligible. Studies were excluded if they focused on adapted or parasports or included participants who had undergone corrective surgery. DATA SYNTHESIS: Two independent raters conducted screening, extracted data, and assessed quality/risk of bias. Meta-analyses were performed for cam and pincer morphology prevalence, stratified by age group. Methods of clinical assessment and diagnostic imaging were descriptively reported. The primary analysis compared morphologies between adolescent and young adult athletes with subgroup (hip vs participant) and factor (sex) analyses. RESULTS: Forty-seven studies reporting on 1241 adolescents (16% female) and 2462 young adults (20% female) were included. Primary analysis estimates for the prevalence of cam morphology (48%; 95% confidence interval [CI]: 38, 58) and pincer morphology (18%; 95% CI: 7, 32) indicated no difference between age groups. Many studies (n = 17, 35%) assessed FAI syndrome according to Warwick recommendations (signs, symptoms, imaging). Few studies stratified findings by symptomatic state. CONCLUSION: Cam morphology appeared to develop in early adolescence. Few studies reported findings in females, and diagnostic methods were inconsistent.

BACKGROUND: Hip arthroscopy for femoroacetabular impingement (FAI) in professional athletes is associated with significant improvements in postoperative pain and function and a return-to-sport (RTS) rate >80%. However, RTS rate after hip arthroscopy for FAI in professional athletes with borderline dysplasia is unknown.

PURPOSE: To assess RTS rates exclusively in professional athletes with borderline dysplasia after hip arthroscopy for treatment of FAI.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: A total of 40 professional and Olympic athletes (42 hips) with borderline dysplasia (lateral center edge angle [LCEA] 18°-25°) underwent hip arthroscopy for FAI between 2005 and 2022. RTS was defined as competing in a single professional game at an equal level after surgery. Data were retrospectively obtained for each athlete from publicly available sport-specific data sources.

RESULTS: The study included 42 hips. Patients undergoing primary hip arthroscopy demonstrated a 79% RTS rate, whereas patients undergoing revision hip arthroscopy demonstrated a 25% RTS rate (P = .006). Among athletes who successfully returned, RTS occurred at a median of 7.5 months (range, 3.1-24.3 months) after surgery. The mean age at the time of surgery was 28.9 years (range, 18-53.5 years). In total, 21 hips (50%) had an Outerbridge grade 3 or 4 defect at the time of surgery, and 10 (24%) underwent a microfracture procedure. Older age (P = .041) and history of previous hip arthroscopy (P = .008) were associated with a lower likelihood of return to professional sport. No statistically significant association was found between femoral version, LCEA, alpha angle, the presence of Outerbridge grade 3 or 4 defect, or minimum joint space and RTS.

CONCLUSION: In the primary setting, professional athletes with borderline hip dysplasia who underwent hip arthroscopy for FAI demonstrated a 79% RTS rate. The mean time to return was 7.5 months, with older age and a history of prior hip arthroscopy predictive of a lower likelihood of RTS (25% RTS among revision cases). Hip arthroscopy for FAI in professional athletes with borderline dysplasia was effective for returning the majority of these athletes to their preoperative level, especially in the primary setting.

BACKGROUND: Labral reconstruction has become an essential technique for treating irreparable acetabular labral pathology. While both segmental and circumferential reconstruction techniques are utilized, it remains unclear whether one provides superior clinical outcomes.

PURPOSE: To compare patient-reported outcomes, complications, and reoperation rates between segmental and circumferential labral reconstruction.

STUDY DESIGN: Meta-analysis.

METHODS: A systematic review of the PubMed, Embase, and Scopus databases was performed in accordance with PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines on February 2, 2025. Studies were included if they reported clinical outcomes after arthroscopic hip labral reconstruction using either segmental or circumferential techniques. Data were extracted on patient characteristics, surgical details, patient-reported outcome measures, complications, revision arthroscopy, and conversion to total hip arthroplasty (THA). Meta-analyses were performed using random-effects models, and heterogeneity was assessed using the I2 statistic.

RESULTS: A total of 28 studies consisting of 1817 hips were included, with 1086 undergoing segmental and 731 undergoing circumferential reconstruction. Patient characteristics were similar between groups, except for a lower proportion of women in the segmental cohort than circumferential cohort (44.6% vs 73.2%; P < .001). Both techniques resulted in significant improvements in all patient-reported outcomes, including the Harris Hip Score, Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports, International Hip Outcome Tool-12 score, Short Form-12 score, and visual analog scale pain score, with no significant differences between groups (all P > .05). Complication rates and revision rates were comparable (P = .05 and P = .06, respectively). However, circumferential reconstruction was associated with a significantly lower conversion to THA compared with segmental reconstruction (P = .01).

CONCLUSION: Both segmental and circumferential labral reconstruction techniques provide significant and comparable improvements in functional outcomes and pain. Circumferential reconstruction was associated with a lower pooled rate of conversion to THA; however, causality cannot be inferred given the heterogeneity, nonrandomized design, and differences in follow-up duration between studies.

PURPOSE OF REVIEW: Acetabuloplasty is a common component of hip arthroscopy for pincer-type and mixed femoroacetabular impingement (FAI), yet the optimal degree of correction remains controversial. Historically, rim trimming has often been guided by radiographic normalization, particularly of the lateral center-edge angle (LCEA). The purpose of this review is to synthesize current evidence regarding acetabular morphology, radiographic assessment, clinical outcomes related to the degree of acetabular correction, and intraoperative strategies that support optimal correction during acetabuloplasty.

RECENT FINDINGS: Recent literature suggests that acetabular overcoverage should not be viewed as a uniform indication for [aggressive] rim resection. Although the LCEA remains a useful measure of acetabular coverage, it incompletely captures focal versus global overcoverage, acetabular version, and dynamic impingement. Mid-term studies have demonstrated favorable outcomes after hip arthroscopy for pincer morphology, with no consistent relationship between postoperative LCEA normalization and patient-reported outcomes. In addition, patients with residual postoperative overcoverage may achieve outcomes comparable to those with normalized coverage and may actually demonstrate lower rates of conversion to arthroplasty. At the same time, excessive rim resection risks iatrogenic undercoverage, instability, edge loading, and accelerated degeneration. Current evidence supports a patient specific rather than radiographically uniform approach to acetabuloplasty. Successful treatment appears to depend on restoring functional femoroacetabular clearance while preserving sufficient acetabular coverage for joint stability and load distribution. Incremental resection, dynamic intraoperative reassessment, labral preservation, and balanced correction of acetabular- and femoral-sided pathology are central to this strategy. Future studies should emphasize three-dimensional assessment, standardized reporting, and longer-term evaluation of joint preservation.

PURPOSE OF REVIEW: Osteonecrosis of the femoral head (ONFH) is a progressive condition disproportionately affecting young adults and is a leading indication for total hip arthroplasty in young adults. This review aims to provide a contemporary overview of ONFH with emphasis on treatment strategies aimed to prevent femoral head collapse and disease progression as supported by recent clinical research from the past five years.

RECENT FINDINGS: The 2019 revised ARCO classification has emerged as the most clinically applicable staging system, guiding treatment selection based on lesion size, location, and collapse status. Core decompression remains the surgical mainstay for pre-collapse disease. Recent evidence supports the addition of hip arthroscopy to improve clinical outcomes and increase native hip survival rates. Augmentation strategies including bone marrow aspirate concentrate (BMAC), mesenchymal stem cells (MSCs), bone grafting, and hip arthroscopy have demonstrated the most promising results when combined with core decompression in early-stage disease. Pharmacologic agents, including bisphosphonates and denosumab, have shown meaningful benefit in slowing disease progression but remain adjunctive. Total hip arthroplasty continues to demonstrate excellent long-term outcomes for post-collapse stages, even in younger patient populations. Management to prevent collapse and disease progression of ONFH remains a challenge. Joint preservation through early surgical intervention with augmentation strategies, such as addition of hip arthroscopy, bone grafting, and biologic regenerative biologic therapies represent promising advancements in ONFH management. However, the existing literature remains limited by heterogeneous study designs, small sample sizes, and inconsistent outcome reporting.

PURPOSE OF REVIEW: Periacetabular osteotomy (PAO) is an established and effective surgical treatment for symptomatic acetabular dysplasia in adolescents and young adults with healthy articular cartilage. While outcomes and technical surgical considerations are well described, perioperative management practices vary significantly across institutions. The purpose of this narrative review was to synthesize current literature on evidence-based best practices for perioperative management of patients undergoing PAO and to identify knowledge gaps for future investigation.

RECENT FINDINGS: A comprehensive review of the literature was performed focusing on perioperative care across four phases: preoperative, intraoperative, acute postoperative, and rehabilitation. Areas of emphasis included laboratory evaluation and nutritional optimization, mental health screening, patient education, blood loss mitigation strategies, pain control, venous thromboembolism and heterotopic ossification (HO) prophylaxis, and postoperative rehabilitation protocols. Strong evidence exists to support specific intraoperative practices such as tranexamic acid administration, controlled hypotension, and fascia iliacus blocks for pain control. Conversely, limited or heterogeneous evidence exists regarding preoperative laboratory testing, psychosocial interventions, standardized opioid prescribing, venous thromboembolism prophylaxis regimens, and rehabilitation protocols. Psychosocial health and preoperative educational interventions appear underutilized despite growing evidence of their impact on outcomes. Significant gaps remain, particularly regarding preoperative optimization and rehabilitation strategies. Continued high-quality research is needed to establish standardized, evidence-based perioperative care pathways to further improve outcomes following PAO.

BACKGROUND: Developmental hip dysplasia (DDH) is now considered the primary cause of early hip arthritis. Complications of missed or delayed DDH may be minimized with early diagnosis and effective nonoperative interventions. The standard of care in the United States for detecting DDH is selective screening whereby ultrasound is only performed in infants with an abnormal physical examination or risk factors. A cost-effectiveness analysis, considering health utilities and lifespan costs, is warranted.

METHODS: A Markov model was designed comparing 7 DDH screening strategies: Universal ultrasound screening at birth 2 weeks (USB); selective ultrasound screening at birth/2 weeks (SSB); universal ultrasound screening at 6 weeks (US6); selective ultrasound at 6 weeks (SS6); universal hybrid screening with ultrasound birth 2 weeks for positive examination and at 6 weeks for all others (UHS); a German national model with ultrasound at birth/2 weeks for instability or risk factors and all others at 6 weeks; and a no ultrasound screening. A literature review captured relevant probabilities, costs, and incidences. Society and payer perspectives were analyzed. Deterministic and probabilistic sensitivity analyses were used.

RESULTS: From a societal perspective, US6 was more effective (77.08 vs. 77.06 quality-adjusted life years (QALYs)) yet minimally more costly ($5,629.68 vs. $5,471.50) than SS6. Using a willingness-to-pay threshold of <$100,000/QALY, US6 was more cost-effective than SS6 (incremental cost effectiveness ratio [ICER] = $7,833.45/QALY). From the payer perspective, US6 was again cost-effective relative to SS6 (ICER = $8,224.57/QALY). US6 was overall cost-effective (<$100,000/QALY) in 50.4% of 10,000 probabilistic sensitivity analysis iterations assessing societal costs (vs. 20.8% UHS, 13.2% SS6, 12.6% German, 2.6% USB, and 0.5% SSB) and 50.7% of payer iterations (vs. 21.0% UHS, 13.4% SS6, 12.3% German, 2.3% USB, and 0.4% SSB). UHS was the second most cost-effective (77.06 QALYs, societal = $5,668.58, payer = $4,351.63). Differences in mean costs and QALYs among leading strategies were small.

CONCLUSION: US6 was the most cost-effective strategy in the base case from both societal and payer perspectives. Given small differences in mean costs and QALYs among leading strategies, implementation feasibility and outcome distribution may be important policy considerations in the US context. A UHS strategy may represent a pragmatic pathway for adoption while preserving broader detection benefits.

LEVEL OF EVIDENCE: III. See Instructions for Authors for a complete description of levels of evidence.

BACKGROUND: Long-term outcomes of femoroacetabular impingement (FAI) surgery, particularly survivorship, are critical to guide treatment decision-making and patient counseling, yet only a limited number of studies have reported mid- to long-term survivorship. The purpose of this study was to report survivorship rates at a mean 10-year follow-up in a large, multicenter FAI surgery cohort and to identify clinical predictors of survivorship.

METHODS: A prospective, multicenter cohort study assessed patients treated for FAI with hip arthroscopy or surgical dislocation from 2008 to 2012. At a minimum of 8 years, 362 hips (80.1%) had follow-up that permitted assessment of total hip arthroplasty (THA)-free survivorship. A Cox proportional-hazards model was developed to identify risk factors for THA.

RESULTS: tThe cohort included 362 hips with a mean patient age of 32.1 years; 53% were in females, and 95.6% were in Caucasian patients. The THA-free survivorship of the cohort was 90.6% at a mean of 10.4 ± 1.6 years postoperatively. Risk factors for THA were older age at surgery (p = 0.01), male sex (p = 0.02), body mass index of ≥30 kg/m 2 (p = 0.009), and femoral head chondromalacia (p < 0.001).

CONCLUSIONS: This study demonstrates that FAI surgery yielded durable 10-year THA-free survivorship of 90.6%. Older age at surgery, obesity, male sex, and femoral head chondromalacia were key predictors of conversion to THA.

LEVEL OF EVIDENCE: Therapeutic Level II . See Instructions for Authors for a complete description of levels of evidence.

OBJECTIVES: To determine the prevalence of femoroacetabular impingement syndrome, primary cam morphology, pincer morphology and acetabular dysplasia in professional female football players. The secondary aim was to explore a dose-response relationship between sport frequency, age of menarche, and the development of femoroacetabular impingement syndrome and primary cam morphology.

DESIGN: Cross-sectional.

METHODS: Questionnaires obtained information on presence of groin pain and current/previous sport frequencies. Physical examination included internal hip rotation and the flexion-adduction-internal rotation test. Anteroposterior and frog-leg lateral radiographic views were used to measure alpha angles and lateral centre-edge angles. Femoroacetabular impingement syndrome was defined by presence of groin pain, a positive flexion-adduction-internal rotation test, and primary cam morphology (alpha angles 60°) or pincer morphology (centre-edge angles ≥ 40°). Acetabular dysplasia was defined as lateral centre-edge angles < 20° and borderline dysplasia as lateral centre-edge angles 20-25°. Dose-response associations were analysed by logistic regression using generalised estimating equations.

RESULTS: One hundred professional female football players (mean (±standard deviation) age = 20.4 (±3.7) years) participated. Per person prevalence of femoroacetabular impingement syndrome was 3%. Per person prevalences for hip morphologies were: primary cam morphology 49%, pincer morphology 10%, borderline dysplasia 11% and dysplasia 1%. There was no dose-response relationship between previous sport frequency or age of menarche, and prevalence of femoroacetabular impingement syndrome and primary cam morphology.

CONCLUSIONS: In professional female football players, the prevalence of femoroacetabular impingement syndrome is low, whilst the prevalence of primary cam morphology is relatively high. The aetiology of femoroacetabular impingement syndrome and primary cam morphology in female football players may not be solely driven by high load activity during skeletal maturation but is likely multifactorial and may differ from that in males.

BACKGROUND: Ligamentum teres lesions are increasingly linked to hip pain and poor surgical outcomes. However, the extent of damage to the full ligamentous-fossa-foveolar complex (LFFC) and the factors associated with this finding remain unclear in young patients undergoing joint-preserving surgery.

QUESTIONS/PURPOSES: In this study, we sought (1) to determine the percentage of patients undergoing surgical hip dislocation for femoroacetabular impingement who have diagnosable LFFC lesions using a previously validated grading system and (2) to identify clinical and radiographic factors associated with more severe LFFC damage.

METHODS: Between July 2016 and December 2023 the senior author treated 402 hips with surgical hip dislocation for symptoms and radiological signs of femoroacetabular impingement (cam morphology, decreased acetabular coverage, or femoral version abnormalities) without advanced osteoarthritis (Tönnis > II). Based on that, 34% (136 of 402) were excluded because of previous surgery, posttraumatic FAI etiologies, incomplete documentation, tumor associated, pediatric hip disorders (Perthes disease and slipped capitis femoris epiphysis), or avascular necrosis. This left 66% (266 of 402) for final analysis in this retrospective, institutional review board-approved study. Mean age was 29 ± 8 years, and 46% (122 of 266) were male. Standardized AP and axial radiographs assessed acetabular and femoral pathomorphology; CT scans were used to determine femoral version. Using a previously validated and established grading system, we determined (1) the percentage of patients undergoing surgical hip dislocation who have LFFC lesions and (2) the demographic, radiographic, and intraoperative factors associated with those lesions.

RESULTS: Substantial LFFC damage was present in 65% (173 of 266) of hips. The ligamentum teres, fossa, and fovea were substantially affected in 44% (118 of 266), 52% (138 of 266), and 51% (135 of 266) of hips, respectively; 21% (57 of 266) of hips had severe lesions to all three structures. Patients with ligamentum teres injuries also had concomitant fossa and fovea damage. After controlling for potential confounding variables such as age, sex, and radiographic parameters, we found that male sex and abnormal femoral version (< 10° or > 25°) were associated with severe LFFC damage (hazard ratio [HR] 0.4 (95% confidence interval [CI] 0 to 1); p = 0.004 and HR 2 (95% CI 1 to 4); p = 0.03, respectively). Acetabular undercoverage was not associated with a greater likelihood of LFFC damage being present.

CONCLUSION: In joint-preserving hip surgery, the primary focus is usually on the labrum and the peripheral compartment, but our findings show that lesions to the LFFC are also very common. As older age, male sex, and femoral version abnormalities were associated with more severe damage, these factors should be incorporated into preoperative considerations, and the accuracy of MRI for detecting LFFC damage should be evaluated. Future studies should also determine how these LFFC lesions influence symptoms and long-term outcomes and identify which management strategies best address them.

LEVEL OF EVIDENCE: Level III, prognostic study.

OBJECTIVE: To describe the imaging features of osteonecrosis of the femoral head (ONFH) on 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography (PET)/CT and explore whether PET/CT can raise suspicion for ONFH in patients with lymphoma.

METHODS: A retrospective analysis was conducted on the clinical data, PET/CT, and MRI findings of 17 patients with lymphoma and ONFH. The 18F-FDG uptake of ONFH was recorded, and the maximum standardized uptake value (SUVmax) of ONFH was measured. The staging and extent of ONFH, and other bone involvements, were visually assessed. Lymphoma disease status was evaluated using the Deauville criteria.

RESULTS: A total of 31 femoral heads were involved (2 stage 1, 24 stage 2, 4 stage 3, 1 stage 4). The median SUVmax was higher in stage 3-4 lesions (5.27) than in stage 1-2 lesions (1.37) (P = 0.002). Regarding 18F-FDG uptake patterns, all stage 1 lesions showed normal uptake; among stage 2 lesions, 11 showed increased uptake, 5 showed peripheral increased with central decreased uptake, 2 showed decreased uptake, and 6 showed normal uptake; all stage 3-4 lesions demonstrated increased uptake. On CT, the extent of all stage 2-4 lesions matched MRI findings. Nine patients had osteonecrosis in other bones, including the humeral heads (n = 9), bilateral iliac bones (n = 6), and vertebrae/ribs/scapulae (n = 1).

CONCLUSIONS: In patients with lymphoma, ONFH exhibits variable degrees of 18F-FDG uptake and may be accompanied by involvement of other bones. PET/CT may raise suspicion for ONFH and detect multiple bone involvements during lymphoma assessment.

AIMS: Occupational outcomes after periacetabular osteotomy (PAO) remain underexplored. The aims were to: 1) to determine rate and duration to return to work (RTW) after PAO; 2) to analyze frequency and reasons for occupational change; and 3) assess career trajectories of students undergoing PAO.

METHODS: We retrospectively analyzed 117 patients who underwent PAO between January 2015 and June 2017, with a mean follow-up of 63.2 months (SD 10.2). A total of 90 patients were employed; 27 were students. Work-related outcomes were assessed via questionnaire, including RTW status, duration of work absence, occupational change, and whether PAO was considered reason for job change. Preoperative workload was assessed by the Reich Committee for Working Time Determination (REFA) classification. Returnees and non-returnees were compared, and predictors of occupational change were assessed with logistic regression.

RESULTS: Among 90 employed patients, 58 (64.4%) returned to their preoperative occupation, while 32 (35.6%) changed jobs. Overall, 14 patients (15.6% of all employed patients) reported that the hip that had undergone PAO was the reason for occupational change. Non-returnees reported higher preoperative pain (Numeric Rating Scale for pain 7.9 vs 7.0, p = 0.027), worse Hip disability and Osteoarthritis Outcome Score (HOOS)-Symptoms (42.3 vs 55.6, p = 0.038) and HOOS-Activities in daily living (44.1 vs 60.5, p = 0.015), higher workload-grades (0 (0 to 1) vs 2 (1 to 3), p < 0.001), and longer work absence (33.4 vs 26.7 weeks, p = 0.024). Logistic regression identified workload as the only independent predictor of occupational change (odds ratio up to 13.1 for heavier workload). The median time to job change was 86 weeks (IQR 10 to 208). Most changes occurred between one and two years postoperatively. Among students, 87.5% were employed at follow-up, most in sedentary (50%) or light (43%) occupations. Only one reported that PAO had influenced career choice.

CONCLUSION: PAO enables the majority of young adults to RTW, but more than one third adapt their occupation in the mid-term, with higher preoperative workload being the key determinant. Despite improved hip function, occupational adaptations remained common, while long-term career trajectories in students were largely unaffected.

AIMS: To determine the prevalence of MRI-confirmed ischiofemoral impingement (IFI) in young patients with nonarthritic hip pain, and to evaluate the associations of femoral, acetabular, pelvic, and spinopelvic parameters with IFI.

METHODS: We included 250 patients with nonarthritic hip pain who underwent standardized imaging (MRI and CT, lateral standing and deep-seated spinopelvic radiographs). IFI was diagnosed by quadratus femoris oedema/atrophy. IFI-positive/negative hips were compared for morphological and spinopelvic parameters. Underlying pathologies (e.g. femoroacetabular impingement, dysplasia) were documented. Multivariate regression identified independent predictors of IFI and determinants of quadratus femoris space (QFS).

RESULTS: IFI was identified in 14/250 patients (5.6%), all female. IFI cases had significantly reduced ischiofemoral space (24.8 mm (SD 6.7) vs 34.9 mm (SD 10.2); p < 0.001) and QFS (9.2 mm (SD 3.4) vs 20.7 mm (SD 7.0); p < 0.001). IFI cases demonstrated larger ischial angle (135.7° (SD 3.0°) vs 132.2° (SD 4.0°); p = 0.002), higher femoral version (16.5° (SD 10.3°) vs 10.4° (SD 12.3°); p = 0.031), and reduced femoral (34.2 mm (SD 5.6) vs 37.7 mm (SD 5.9); p = 0.016) and acetabular offset (29.4 mm (SD 3.5) vs 32.0 mm (SD 4.8); p = 0.036). In standing, IFI cases tended to have lower lumbar lordosis (LL) (55.31° (SD 7.95°) vs 59.91° (SD 10.50°); p = 0.077), higher pelvic tilt (15.68° (SD 4.73°) vs 12.39° (SD 6.20°); p = 0.047), and smaller mismatch between pelvic incidence and LL (-2.39° (SD 7.18°) vs -7.82° (SD 10.00°); p = 0.034). The change in LL across standing to deep-flexed sitting transition (ΔLL) was lower in IFI cases (50.31° (SD 10.89°) vs 56.89° (SD 10.64°); p = 0.020). Multivariate regression identified reduced QFS (odds ratio (OR) 1.92, 95% CI 1.30 to 2.89; p < 0.001) and greater LL (OR 1.16, 95% CI 1.00 to 1.33; p = 0.047) as independent predictors of IFI. Size of QFS was associated positively with femoral offset (β = 0.35; p < 0.001) and mismatch between pelvic incidence and LL (β = 0.18; p = 0.028), and negatively with ischial angle (β = -0.34; p < 0.001), femoral version (β = -0.14; p = 0.016), and standing pelvic tilt (β = -0.16; p = 0.026).

CONCLUSION: IFI occurred in 5.6% of patients and was characterized by a distinct morphometric and sagittal alignment profile, including increased femoral version, reduced offset, greater ischial angle, reduced LL, increased pelvic tilt, and diminished spinal motion. These findings support a multifactorial model in which hip morphology and spinopelvic alignment jointly influence posterior hip clearance in IFI.

Background: Femoroacetabular impingement syndrome (FAIS) is a common cause of hip pain and functional limitation in young and physically active individuals. Although hip arthroscopy is an established treatment when conservative management fails, objective data on early postoperative changes in active hip range of motion (ROM) remain limited. This study aimed to evaluate changes in active hip ROM three months after arthroscopic treatment for FAIS using inertial measurement units (IMUs) and to investigate their relationship with patient-reported outcomes. Methods: A prospective cohort of forty-two patients (mean age 36 ± 9 years; 64% male) undergoing hip arthroscopy for FAIS was assessed preoperatively and at a three-month follow-up. Active hip ROM-including flexion, internal rotation, external rotation, and total rotation-was measured using IMU sensors, while subjective outcomes were evaluated using the Hip disability and Osteoarthritis Outcome Score (HOOS). Results: Significant improvements were observed across all HOOS subscales at follow-up (all p < 0.001). The HOOS Total score increased from 57 ± 15 to 83 ± 11. Clinical recovery, defined by the Minimal Important Change (MIC), was achieved by 74% of patients for Symptoms, 81% for Pain, 81% for ADL, 83% for Sport, and 67% for Quality of Life (QOL). Active hip ROM in the operated hip increased significantly for internal rotation (19.6° ± 11.9° to 26° ± 8°), external rotation (37° ± 10° to 40° ± 8°), and total rotation (57° ± 15° to 67° ± 12°). Changes in hip flexion were not clinically meaningful (98° to 100°), and no changes were observed in the non-operated hip. Spearman's analysis showed weak and inconsistent correlations between active ROM and HOOSs (r ranging from -0.34 to 0.31). Conclusions: Hip arthroscopy for FAIS leads to early improvements in both patient-reported outcomes and active hip mobility, particularly in rotational movements, although the relationship between ROM and subjective outcomes appears weak.

INTRODUCTION: While the hip, pelvis, and lumbar spine are known to move synchronously, their exact relationship has yet to be determined. The aim of this study was to define the biomechanical relationship between the hip, pelvis, and lumbar spine.

METHODS: A cohort of fifty healthy subjects between 18- and 35-years-old were recruited to participate, including 25 males and 25 females. Exclusion criteria included presence of back or hip pain, inability to stand upright or sit with hips flexed to 90°, history of ankylosing spondylitis, femoroacetabular impingement, or prior hip or spine surgery. Three lateral radiographs were obtained for each patient, including standing, relaxed seated, and the flexed-forward seated views. Radiographic variables measured included sacral slope (SS), pelvic-femoral angle (PFA), and lumbar lordosis (LL). Calculations included the change in SS (ΔSS), the change in PFA (ΔPFA), the change in LL (ΔLL). Pearson correlations were used to determine the relationship between ΔSS, ΔPFA, and ΔLL with significance set to p<.05.

RESULTS: The average age of participants was 25.70±2.34 years with a body mass index (BMI) of 24.10±3.02 kg/m2. For every degree increase of hip flexion, lumbar flexion decreased 0.84° (R=-0.75, p<.001). Similarly, ΔPFA was strongly negatively correlated with ΔSS, with every degree increase of ΔPFA yielding a decrease of 0.71° in ΔSS (R=-0.85, p<.001). ΔSS was strongly correlated with the ΔLL. For every degree that ΔLL increased, ΔSS increased 0.63° (R=0.85, p<.001).

CONCLUSIONS: Motion between the hip, pelvis, and lumbar spine is highly correlated. For every degree increase of hip flexion, the pelvis tilts posteriorly 0.71, causing the lumbar spine to flex 1.58 degrees to maintain upright posture. For every degree increase of hip flexion, the lumbar spine decreases flexion 0.86 degrees. Given the increased interest and clinical applicability of spinopelvic biomechanics in the spine community, these definitions are essential to moving forward with research in this topic.

Orthopaedic surgical decision making is a combination of clinical intuition, radiological measurements, and referenced standards. As clinicians and researchers, we consider hip pathology as a mechanical problem described in geometric and statistical language. For a clinical measurement to be useful, it must be easy to perform, reproducible, and demonstrably associated with the risk of the condition it seeks to diagnose or prevent. Using acetabular dysplasia as an analytic lens, this review discusses what our radiographs actually tell us about hip morphology risk, by separating population reference ("normative") intervals from outcome-anchored decision limits and by tracing the evidentiary lineage of the field's workhorse measurements. We revisit the origins, current use, and statistical power of the lateral center-edge angle, acetabular index/Tönnis angle, femoral head extrusion index, and Graf ultrasonography classification and synthesize what is known about their reproducibility and what clinical decisions can appropriately be made. We examine how nomenclature drift fuels routine miscommunication and show that superficially similar measurements are often tied to reference datasets they were neither derived from nor validated against. The current, normal or not, phenotypic model of risk allocation is considered, and the alternative of a continuous, dose-response relationship is proposed. The aim of this narrative review is to prompt clinicians and researchers to consider has our use of legacy morphological risk models actually curtailed osteoarthritis progression in conditions such as hip dysplasia and can we continue to depend on them? Or do models grounded more in lineage than validation now warrant a fundamental reconstruction.

BACKGROUND: Ultrasound (US) screening for cam morphology in athletes is rarely performed. Conventional US imaging in the neutral hip position may overlook cam lesions in the anterolateral position, which is the most common location that exhibits cam morphology.

PURPOSE: To investigate US-detected cam-related morphology and prominence in male collegiate soccer players using US with an additional 15° hip extension view and to examine their associations with groin symptoms and functional impairments.

STUDY DESIGN: Cross-sectional study; Level of evidence, 3.

METHODS: This voluntary screening study included 55 male collegiate soccer players (110 hips; mean age, 19.5 ± 1.1 years) from a single varsity team, all of whom were active and without hip or groin pain severe enough to limit soccer participation. US imaging of the femoral head-neck junction was performed in the neutral position and at 15° of hip extension using a linear probe. The femoral morphology on US was classified as normal, flattened, or prominent; and flattened or prominent findings were grouped as cam-positive for analysis. Groin pain and pinching sensations were assessed using questionnaires and flexion adduction internal rotation tests. Four functional parameters were evaluated, and logistic regression analyses were performed to identify factors associated with the current symptoms.

RESULTS: US-based cam-positive morphology was identified in 97 hips (88%) and prominence in 53 hips (48%). The detection rate of US-based cam-positive morphology increased from 79% at 0° to 88% at 15° of hip extension (P = .02), and that of prominence increased from 21% to 48% (P < .0001). Groin pain was present in 25 hips (19%), and pinching sensation was reported with 49 hips (45%). In cam-positive hips, having ≥3 functional deficits (odds ratio [OR], 5.0) and greater side-to-side internal rotation difference (OR, 1.2) predicted groin pain; the same variables (OR, 10.2 and 1.1, respectively) predicted pinching sensation. In prominence-positive hips, ≥3 functional deficits predicted groin pain (OR, 6.5) and pinching sensation (OR, 6.9).

CONCLUSION: US screening with 15° hip extension improved the detection of anterolateral cam-related morphology in male collegiate soccer players. Current symptoms were more strongly associated with multiple functional impairments than with morphology alone.

BACKGROUND: Acetabular wave signs represent a form of cartilage delamination and may progress to more extensive chondral damage in patients with femoroacetabular impingement (FAI). The current lack of high-quality evidence supporting an optimal surgical strategy underscores the need to investigate reverse microfracture as a viable, safe, cost-effective, and cartilage-preserving treatment option.

PURPOSE/HYPOTHESIS: The purpose of this study is to evaluate the clinical and imaging outcomes of arthroscopic treatment of acetabular wave signs using a reverse drilling technique performed from the supralabral region of the acetabulum without damaging the articular cartilage. It was hypothesized that this technique would provide clinical improvement without additional cartilage damage.

STUDY DESIGN: Case series; Level of evidence, 4.

METHODS: A total of 40 patients (mean age, 40.2 ± 9.2 years; 24 women and 16 men) underwent hip arthroscopy with concomitant FAI treatment and reverse microfracture, with a minimum follow-up of 2 years. Outcomes included Harris Hip Score (HHS), visual analog scale (VAS), lateral center-edge angle (LCEA), alpha angle, and magnetic resonance imaging (MRI).

RESULTS: The HHS increased from 68.88 ± 10.81 to 97.90 ± 2.22 (P < .001), and the VAS score decreased from 7.40 ± 1.03 to 1.35 ± 1.08 (P < .001). The alpha angle decreased from 61.88°± 2.50° to 50.05°± 1.75° (P < .001), and the LCEA decreased from 36.75°± 4.66° to 32.43°± 1.92° (P < .001). MRI demonstrated no deterioration in cartilage quality or additional lesions after the procedure, with cartilage appearance similar to adjacent noninjured areas and no evidence of delamination.

CONCLUSION: Reverse microfracture may represent a potential treatment option for acetabular wave signs. In this retrospective series, the procedure was associated with improvement in pain and functional scores, and no evidence of additional cartilage deterioration was observed on postoperative MRI during a minimum 2-year follow-up. However, given the absence of a control group, the specific contribution of the drilling technique to the observed clinical improvements cannot be determined.Clinical improvement likely reflects the combined effect of comprehensive arthroscopic management of FAI rather than the isolated effect of reverse drilling.

BACKGROUND: There is a paucity of literature investigating the impact of cannabis usage on functional outcomes after primary hip arthroscopy surgery to treat symptomatic labral tears.

PURPOSE: To compare patient-reported outcome measures (PROM) for hip arthroscopy patients who did and did not self-report cannabis use, understand how frequency of cannabis use correlates to PROMs, and compare rates of achieving clinically meaningful outcomes for both cohorts.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: This was a matched-control cohort study of patients who underwent primary hip arthroscopy for symptomatic labral tears. Included patients were ≥18 years old and completed baseline and 2-year postoperative outcomes surveys. Excluded patients had missing follow-up data, previous ipsilateral hip surgery or revision surgery, and/or hip dysplasia (lateral center-edge angle ≤20°). Patients were retrospectively divided into 2 groups based on whether they were cannabis naive (CN) or cannabis users by reviewing their social history. The 2 groups were then propensity-matched 1:1 by age, sex, body mass index, and Tönnis grade. PROMs were collected prospectively at baseline and 2 years postoperatively. These included the modified Harris Hip Score, Nonarthritic Hip Score, Hip Outcome Score-Activities of Daily Living, Hip Outcome Score-Sports Specific Subscale, 33-item International Hip Outcome Tool, Lower Extremity Functional Score, and RAND-36 pain subscale (Pain).

RESULTS: In total, 68 patients were included (aged 31.4 ± 9.67 years). Of these, 34 patients had self-reported cannabis use, and 34 did not report use. All PROM scales were similar at baseline (P > .05). Cannabis use was not a predictor of functional outcomes at any time point, including the 2-year follow-up for all PROM scales (P > .05); however, the improvement in Pain scores was significantly better in the CN cohort from baseline to the 2-year follow-up (27.3 ± 28.8 vs 11.6 ± 19.0, P = .012). A linear regression model adjusting for cannabis use frequency found pain scores worsened with increased usage (adjusted mean difference, -2.68; 95% CI, -5.12 to -0.25; P = .031). Further analysis showed no differences in achieving minimal clinically important difference, patient acceptable symptom state, or substantial clinical benefit (P > .05).

CONCLUSION: Self-reported cannabis usage has no impact on raw functional outcomes after hip arthroscopy, but increased usage correlates with worse pain symptoms.

BACKGROUND: Postless traction has been developed to avoid perineal post-related complications in hip arthroscopy. While it is reported to reduce groin-related issues, its effect on overall nerve injury rates, as well as potential new complications such as lumbosacral discomfort, remains unclear.

HYPOTHESIS: Postless traction may be linked to improved clinical outcomes but may carry an increased risk of lumbosacral discomfort.

STUDY DESIGN: Cohort study; Level of evidence, 3.

METHODS: Patients who underwent postless hip arthroscopy were compared with matched patients who underwent conventional post-assisted traction. Patient-reported outcomes, including the Hip Outcome Score-Activities of Daily Living and Sports subscales (HOS-ADL and HOS-SS), the International Hip Outcome Tool-12 (iHOT-12), and the modified Harris Hip Score (mHHS), were collected via follow-up over a mean period of 476 days, ranging from 404 to 560 days. Complications including sensory deficits, perineal injury, and lumbosacral discomfort were also assessed.

RESULTS: A total of 32 patients who underwent postless hip arthroscopy were compared with 64 patients in the control group undergoing post-assisted traction. There was no significant difference in the overall rate of sensory nerve injury between the 2 groups (31.3% vs 32.8%; P = .88). No perineal soft tissue injuries occurred in the postless group, compared with 1 case (1.6%) in the control group (P > .05). However, the incidence of lumbosacral discomfort was significantly higher in the postless group (28.1% vs 6.3%; P = .008). The postless group showed significantly better scores on the HOS-SS (76.81 ± 21.07 vs 66.78 ± 21.30; P = .009) and iHOT-12 (80.57 ± 14.03 vs 65.65 ± 18.00; P < .001), while no differences were found in HOS-ADL or mHHS.

CONCLUSION: Postless hip arthroscopy is associated with superior patient-reported functional outcomes. However, it shows no reduction in the overall rate of sensory nerve injury and is linked to a significantly higher risk of postoperative lumbosacral discomfort.

BACKGROUND: Slipped capital femoral epiphysis (SCFE) is a common adolescent hip disorder occurring during the pubertal growth spurt, and prior studies have demonstrated regional seasonal variation in presentation volume. The relationship between seasonality, socioeconomic deprivation, and disease severity remains incompletely characterized. This study investigated whether SCFE presentation volume demonstrates seasonal variation and whether seasonality is associated with socioeconomic deprivation, body mass index (BMI), and radiographic severity.

METHODS: We retrospectively reviewed children newly diagnosed with SCFE at a single institution in Wisconsin (USA) between January 2012 and March 2024. Variables included age, sex, race, Area Deprivation Index (ADI), BMI, month of symptom onset, Southwick slip angle, stability, chronicity, and symptom duration. Presentation volume was analyzed using 3-month rolling averages and sinusoidal regression with 12-month periodicity. Associations among ADI, BMI, and slip angle were assessed using linear regression and Spearman's correlation.

RESULTS: In total, 122 of 160 patients met the inclusion criteria. SCFE presentation volume demonstrated significant seasonality (p < 0.05). Lower-volume months were associated with higher neighborhood deprivation and greater radiographic severity (p < 0.05). ADI correlated with slip angle (r = 0.29, p < 0.05) and BMI (r = 0.33, p < 0.05), whereas BMI was not significantly associated with slip angle. Chronic slips demonstrated greater slip angles than acute presentations (p < 0.05).

CONCLUSIONS: SCFE presentation volume in Wisconsin follows a significant seasonal pattern, and social determinants of health may influence the timing of presentation and disease severity.

Background: Developmental dysplasia of the hip (DDH) is the most common congenital musculoskeletal disorder in newborns. Flexion-abduction orthoses are widely used in early treatment; however, in vivo data on their biomechanical load characteristics remain limited. This study aimed to evaluate axial force transmission in a hip flexion-abduction orthosis and to compare load patterns between healthy newborns and infants with DDH. Methods: In this exploratory observational study, 36 newborns (19 healthy, 17 with unilateral DDH) were examined within the first week of life. Axial forces transmitted through a Mittelmeier-Graf hip flexion-abduction orthosis (MGO) were measured using integrated force sensors under symmetrical and asymmetrical adjustment configurations. Intergroup comparisons were performed using non-parametric statistical tests. Results: Mean axial forces were significantly higher in healthy infants than in those with DDH under both symmetrical (4.02 N vs. 2.51 N; p = 0.019) and asymmetrical (3.67 N vs. 1.83 N; p = 0.001) conditions. Relative load corresponded to approximately 11-12% of body weight in healthy infants and 5-7% in the DDH group. No significant intra-individual differences were observed between dysplastic and contralateral hips. Orthosis configuration (symmetrical vs. asymmetrical) did not significantly affect load distribution. Conclusions: This exploratory in vivo study demonstrates that axial load transmission in a hip flexion-abduction orthosis is low and influenced by underlying hip pathology. Infants with DDH generate lower forces than healthy newborns, potentially reflecting altered biomechanics. As no significant differences were observed between orthosis configurations, symmetrical adjustment may be favored in clinical practice due to better usability and compliance. Further studies with larger cohorts are needed to confirm these findings.