Enhanced Osteogenesis of Mesenchymal Stem Cells Encapsulated in Injectable Microporous Hydrogel.

Delivery of therapeutic stem cells to treat bone tissue damage is a promising strategy that faces many hurdles to clinical translation. Among them is the design of a delivery vehicle which promotes desired cell behavior for new bone formation. In this work, we describe the use of an injectable microporous hydrogel, made of crosslinked gelatin microgels, for the encapsulation and delivery of human mesenchymal stem cells (MSCs) and compared it to a traditional nonporous injectable hydrogel. MSCs encapsulated in the microporous hydrogel showed rapid cell spreading with direct cell-cell connections whereas the MSCs in the nonporous hydrogel were entrapped by the surrounding polymer mesh and isolated from each other. Microporous hydrogel induced more robust osteogenic differentiation of MSCs and calcium mineral deposition than the nonporous hydrogel confirmed by alkaline phosphatase (ALP) assay and calcium assay. RNA-seq confirmed the upregulation of the genes and pathways that are associated with cell spreading and cell-cell connections, as well as the osteogenesis in the microporous hydrogel. These results demonstrate that the microgel-based injectable hydrogels can be useful tools for therapeutic cell delivery for bone tissue repair.

Telehealth Potential in Pediatric Orthopaedics and Sports Medicine Care is Comparable to In-Person Care But Disparities Remain.

BACKGROUND: Understanding the challenges and potential of telehealth visits (THVs) in a large population can inform future practice and policy discussion for pediatric orthopaedic and sports medicine (OSM) care. We comprehensively assess telehealth challenges and potential in a large pediatric OSM population based on access, visit completion, patient satisfaction, and technological challenges. METHODS: Demographics, address, insurance, visit information, patient feedback, experience with video visits, and technical challenges of all 2019 to 2020 visits at our hospital were assessed (3,278,006 visits). We evaluated the differences in rate of telehealth utilization, rate of patient adherence, disparities in care access and patient satisfaction, and technological issues. RESULTS: Compared with in-person prepandemic visits, THVs had lower ratios of non-White patients (by 5.8%; P<0.001), Hispanic patients (by 2.8%; P<0.001) and patients with public insurance (by 1.8%; P<0.001), and a higher mean distance between the patient's residence and clinic (by 18.8 miles; P<0.001). There were minimal differences in median household income (average $2297 less in THV; P<0.001) and social vulnerability index (average 0.01 points lower in THV; P<0.001) between groups. THVs had comparable patient satisfaction to in-person visits. Non-White patients, Hispanics, and those with public insurance had lower ratings for both in-person visits and THVs and had more technical difficulties during their THV. CONCLUSIONS: Telehealth is a viable method of care for a range of pediatric OSM conditions, providing a similar quality of care as in-person visits with a greater geographic reach. However, in its current format, reduced disparities were not observed in pediatric OSM THVs. LEVEL OF EVIDENCE: Level III.

Is Immobilization Technique Associated With Postoperative Pubic Rami Diastasis Following Bladder Exstrophy Closure?

OBJECTIVE: Pelvic osteotomies relieve tension of the bladder and fascial closures during bladder exstrophy repair. Multiple techniques for postoperative immobilization of the pelvis and lower extremities have been described. The primary aim of this study was to assess differences in short and long-term changes in pubic rami diastasis when comparing Bryant traction to spica cast immobilization. Secondary aims included a comparison of length of stay, skin-related complications, and urologic outcomes. METHODS: We performed a single-institutional retrospective review of bladder exstrophy patients younger than 18 months of age who underwent posterior pelvic osteotomy and bladder exstrophy closure from April 2005 to April 2020. Short-term and long-term pubic rami diastasis were defined as postoperative measurements ≤6 months and ≥12 months, respectively. Secondary outcomes included length of stay, pressure ulcer, skin rash/abrasion, urethrocutaneous fistula, and bladder or fascial dehiscence rates. Multivariable logistic regression assessed for an association between immobilization type and degree of diastasis while controlling for age at the time of diastasis measurement and sex. RESULTS: Fifteen patients underwent Bryant traction and 36 patients underwent spica cast immobilization. In both the short-term and long-term, there was a greater reduction in pubic diastasis in the spica cast group ( P = 0.002 and P = 0.05, respectively). After adjustments, there were higher odds of having a greater reduction in pubic rami diastasis in both the short-term (odds ratio: 2.71, 95% CI: 1.52-4.86, P = 0.001) and long-term (odds ratio: 2.41, 95% CI: 1.00-5.80, P = 0.05). Length of stay was significantly higher in Bryant's traction group (26 vs 19 d, P < 0.001). Rates of pressure ulcers were higher in the Bryant traction group (26.7% vs 0%, P = 0.005). Rates of skin rash/abrasions, urethrocutaneous fistula, and bladder/fascial dehiscence did not differ. CONCLUSIONS: Spica cast immobilization is a safe and effective immobilization method. Compared with Bryant traction, spica cast immobilization was associated with a greater reduction in postoperative pubic diastasis both short and long-term, along with a shorter length of hospitalization and reduced rate of pressure ulcers. LEVEL OF EVIDENCE: Level III-therapeutic study.

Comparison of Contrast-enhanced Ultrasound and Contrast-enhanced Magnetic Resonance Imaging in the Assessment of Infant Hip Perfusion and Prediction of Proximal Femoral Growth Disturbance Following Closed and Open Reduction for Developmental Dysplasia of the Hip: A Preliminary Study.

OBJECTIVE: Proximal femoral growth disturbance (PFGD) is a significant complication associated with surgical treatment of infant hip dislocation. Contrast-enhanced magnetic resonance imaging (CEMRI) has been utilized to assess perfusion in these hips and avoid PFGD. Contrast-enhanced ultrasound (CEUS) is an imaging technique utilized to evaluate perfusion in other organs. The aims of this study were to compare perfusion of dysplastic infant hips with CEUS and CEMRI after surgical treatment and to determine whether CEUS was as effective as CEMRI at predicting PFGD. METHODS: A retrospective analysis of patients undergoing closed or open reduction for infant hip dislocation between 2012 and 2019 was performed. All patients underwent intraoperative CEUS and postoperative CEMRI to assess femoral epiphyseal perfusion using intravenous contrast. Perfusion status was rated as normal, partially decreased, or globally decreased in both modalities. Agreement in perfusion status between CEUS and CEMRI was assessed. Patients were followed for a minimum of 2 years postoperatively and assessed for PFGD. RESULTS: Eighteen patients (28% males) underwent closed or open reduction at an average age of 8 months (3 to 16 mo). The agreement in perfusion status between CEUS and CEMRI was substantial (α = 0.74). Patients were followed for a median of 3 years. PFGD developed in 3 hips (17%). For the detection of PFGD, both imaging modalities performed very well and with no difference in the diagnostic utility of CEUS compared with CEMRI. Considering normal perfusion alone the accuracy, sensitivity, and specificity for CEUS were 83%, 100%, and 80%, and for CEMRI were 78%, 100%, and 73%, respectively. Considering global decreased perfusion alone, the accuracy, sensitivity, and specificity for CEUS were 94%, 67%, and 100%, and for CEMRI were 89%, 67%, and 93%, respectively. CONCLUSIONS: CEUS is a viable intraoperative method to assess infant hip perfusion. This pilot study appears to be comparable to CEMRI at visualizing perfusion of infant hips and as good or better in predicting PFGD after hip reduction. Prospective studies of this imaging technique should be performed to confirm the findings of this retrospective review. LEVEL OF EVIDENCE: Level II-development diagnostic criteria on the basis of consecutive patients (with generally preferred standard).

Risk Factors for Suboptimal Outcome of FAI Surgery in the Adolescent Patient.

BACKGROUND: Surgical treatment for adolescent patients with femoroacetabular impingement (FAI) is increasing. The purpose of this study was to determine the clinical outcomes of FAI surgery in a multicenter cohort of adolescent patients and to identify predictors of suboptimal outcomes. METHODS: One hundred twenty-six adolescent hips (114 patients < 18 years of age) undergoing surgery for symptomatic FAI were studied from a larger multicenter cohort. The group included 74 (58.7%) female and 52 male hips (41.3%) with a mean age of 16.1 (range 11.3 to 17.8). Clinical outcomes included the modified Harris Hip Score (mHHS), Hip disability and Osteoarthritis Outcome Score (5 domains), and University of California Los Angeles activity score. Failure was defined as revision surgery or clinical failure (inability to reach minimally clinical important differences or patient acceptable symptoms state for the mHHS). Statistical analysis was used to identify factors significantly associated with failure. RESULTS: There was clinically important improvement in all patient-reported outcomes for the overall group, but an 18.3% failure rate. This included a revision rate of 8.7%. Females were significantly more likely than males to be classified as a failure (25.7 vs. 7.7%, P =0.01), in part because of lower preoperative mHHS (59.1 vs. 67.0, P < 0.001). Mild cam deformity (alpha angle <55 degrees) was present in 42.5% of female hips compared with 17.3% male hips. Higher alpha angles were inversely correlated with failure. Alpha angles >63 have a failure rate of 8.3%, between 55 and 63 degrees, 12.0% failure rate, and <55 degrees (mild cam) failure rate of 37.5%. Patients who participated in athletics had a 10.3% failure rate compared with nonathletes at 25.0% ( P =0.03, RR (relative risk) 2.4). CONCLUSIONS: Adolescent patients undergoing surgical treatment for FAI generally demonstrate significant improvement. However, female sex, mild cam deformities, and lack of sports participation are independently associated with higher failure rates. These factors should be considered in surgical decision-making and during patient counseling. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

Arthritis Foundation/HSS Workshop on Hip Osteoarthritis, Part 1: Epidemiology, Early Development, and Cohorts From Around the World.

Far more publications are available for osteoarthritis of the knee than of the hip. Recognizing this research gap, the Arthritis Foundation, in partnership with the Hospital for Special Surgery, convened an in-person meeting of thought leaders to review the state of the science of and clinical approaches to hip osteoarthritis. This article summarizes the recommendations and clinical research gaps gleaned from 5 presentations given in the "how hip osteoarthritis begins" session of the 2023 Hip Osteoarthritis Clinical Studies Conference, which took place on February 17 and 18, 2023, in New York City.

Hip Impingement of severe SCFE patients after in situ pinning causes decreased flexion and forced external rotation in flexion on 3D-CT.

Introduction: In situ pinning is an accepted treatment for stable slipped capital femoral epiphysis. However, residual deformity of severe slipped capital femoral epiphysis can cause femoroacetabular impingement and forced external rotation. Purpose/questions: The aim of this study was to evaluate the (1) hip external rotation and internal rotation in flexion, (2) hip impingement location, and (3) impingement frequency in early flexion in severe slipped capital femoral epiphysis patients after in situ pinning using three-dimensional computed tomography. Patients and methods: A retrospective Institutional Review Board-approved study evaluating 22 patients (26 hips) with severe slipped capital femoral epiphysis (slip angle > 60°) using postoperative three-dimensional computed tomography after in situ pinning was performed. Mean age at slipped capital femoral epiphysis diagnosis was 13 ± 2 years (58% male, four patients bilateral, 23% unstable, 85% chronic). Patients were compared to contralateral asymptomatic hips (15 hips) with unilateral slipped capital femoral epiphysis (control group). Pelvic three-dimensional computed tomography after in situ pinning was used to generate three-dimensional models. Specific software was used to determine range of motion and impingement location (equidistant method). And 22 hips (85%) underwent subsequent surgery. Results: (1) Severe slipped capital femoral epiphysis patients had significantly (p < 0.001) decreased hip flexion (43 ± 40°) and internal rotation in 90° of flexion (-16 ± 21°, IRF-90°) compared to control group (122 ± 9° and 36 ± 11°). (2) Femoral impingement in maximal flexion was located anterior to anterior-superior (27% on 3 o'clock and 27% on 1 o'clock) of severe slipped capital femoral epiphysis patients and located anterior to anterior-inferior (38% on 3 o'clock and 35% on 4 o'clock) in IRF-90°. (3) However, 21 hips (81%) had flexion < 90° and 22 hips (85%) had < 10° of IRF-90° due to hip impingement and 21 hips (81%) had forced external rotation in 90° of flexion (< 0° of IRF-90°). Conclusion: After in situ pinning, patient-specific three-dimensional models showed restricted flexion and IRF-90° and forced external rotation in 90° of flexion due to early hip impingement and residual deformity in most of the severe slipped capital femoral epiphysis patients. This could help to plan subsequent hip preservation surgery, such as hip arthroscopy or femoral (derotation) osteotomy.

Posterior Hip Impingement at Maximal Hip Extension in Female Patients With Increased Femoral Version or Increased McKibbin Index and Its Effect on Sports Performance.

Background: The location of posterior hip impingement at maximal extension in patients with posterior femoroacetabular impingement (FAI) is unclear. Purpose: To investigate the frequency and area of impingement at maximal hip extension and at 10° and 20° of extension in female patients with increased femoral version (FV) and posterior hip pain. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Osseous patient-specific 3-dimensional (3D) models were generated of 50 hips (37 female patients, 3D computed tomography) with a positive posterior impingement test and increased FV (defined as >35°). The McKibbin index (combined version) was calculated as the sum of FV and acetabular version (AV). Subgroups of patients with an increased McKibbin index >70° (24 hips) and FV >50° (20 hips) were analyzed. A control group of female participants (10 hips) had normal FV, normal AV, and no valgus deformity (neck-shaft angle, <139°). Validated 3D collision detection software was used for simulation of osseous impingement-free hip extension (no rotation). Results: The mean impingement-free maximal hip extension was significantly lower in patients with FV >35° compared with the control group (15° ± 15° vs 55° ± 19°; P < .001). At maximal hip extension, 78% of patients with FV >35° had osseous posterior extra-articular ischiofemoral hip impingement. At 20° of extension, the frequency of posterior extra-articular ischiofemoral impingement was significantly higher for patients with a McKibbin index >70° (83%) and for patients with FV >35° (76%) than for controls (0%) (P < .001 for both). There was a significant correlation between maximal extension (no rotation) and FV (r = 0.46; P < .001) as well as between impingement area at 20° of extension (external rotation [ER], 0°) and McKibbin index (0.61; P < .001). Impingement area at 20° of extension (ER, 0°) was significantly larger for patients with McKibbin index >70° versus <70° (251 vs 44 mm2; P = .001). Conclusion: The limited hip extension found in our study could theoretically affect the performance of sports activities such as running, ballet dancing, or lunges. Therefore, although not examined directly in this study, these activities are not advisable for these patients. Preoperative evaluation of FV and the McKibbin index is important in female patients with posterior hip pain before hip preservation surgery (eg, hip arthroscopy).

Treatment of Symptomatic Residual Deformity in Legg-Calvé-Perthes Disease: Mid-Term Outcomes and Predictors of Failure After Surgical Hip Dislocation with Femoral-Head Reshaping and Relative Neck Lengthening.

BACKGROUND: Treating patients with symptomatic hips after healed Legg-Calvé-Perthes disease (LCPD) is challenging, mainly because of the complexity of the deformity. We performed a retrospective study to evaluate clinical and radiographic outcomes, measure the survival rate, and identify predictors of failure following a surgical hip dislocation (SHD) with femoral-head reshaping and relative femoral-neck lengthening for the treatment of symptomatic residual hip deformity after healed LCPD. METHODS: We identified 60 patients undergoing SHD for the treatment of symptomatic residual LCPD deformity. Fifty-one (85%) of the patients (mean age, 16.3 ± 4.7 years; 21 male patients [41%]), were followed ≥4 years after surgery. We defined surgical failure as conversion to, or recommendation for, total hip arthroplasty (THA) or a Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score of ≥10 at the most recent follow-up. We used a multivariable Cox proportional hazards model to identify factors that were predictive of failure. The rate of survival free from failure was estimated using a Kaplan-Meier curve. RESULTS: Twenty (39%) of the patients met 1 of the end-point criteria for surgical failure, while the hips of the remaining 31 (61%) of the patients were successfully preserved at a median follow-up of 10.2 years (interquartile range, 5.7 to 12.9 years). The estimated survival was 80% (95% confidence interval [CI] = 70% to 92%) at 5 years and 66% (95% CI = 53% to 81%) at 10 years. Independent factors associated with surgical failure were the severity of preoperative pain as assessed by the WOMAC pain score (hazard ratio [HR] = 1.16; 95% CI = 1.03 to 1.30; p = 0.01) and the severity of the deformity as assessed by the anteroposterior alpha angle (HR = 1.06; 95% CI = 1.01 to 1.11; p = 0.01). CONCLUSIONS: We found that SHD with relative femoral-neck lengthening and osteochondroplasty of the femoral head-neck junction was associated with improved deformity as assessed radiographically and decreased pain and symptoms of stiffness among patients with symptomatic residual LCPD deformity. Preoperative pain and deformity were identified as predictors of surgical failure. Further research is needed to establish the role of SHD and other procedures in preserving the hip over the long term. LEVEL OF EVIDENCE: Therapeutic L evel IV . See Instructions for Authors for a complete description of levels of evidence.

The Impact of Age on Clinical Outcomes of Acetabular Microfracture During FAI Surgery.

BACKGROUND: Full-thickness acetabular cartilage lesions are common findings during primary surgical treatment of femoroacetabular impingement (FAI). PURPOSE: To evaluate clinical outcomes after acetabular microfracture performed during FAI surgery in a prospective, multicenter cohort. STUDY DESIGN: Cohort Study; Level of evidence, 3. METHODS: Patients with FAI who had failed nonoperative management were prospectively enrolled in a multicenter cohort. Preoperative and postoperative (mean follow-up, 4.3 years) patient-reported outcome measures were obtained with a follow-up rate of 81.6% (621/761 hips), including 54 patients who underwent acetabular microfracture. Patient characteristics, radiographic parameters, intraoperative disease severity, and operative procedures were analyzed. Propensity matching using linear regression was used to match 54 hips with microfracture to 162 control hips (1:3) to control for confounding variables. Subanalyses of hips ≤35 and >35 years of age with propensity matching were also performed. RESULTS: Patients who underwent acetabular microfracture were more likely to be male (81.8% vs 40.9%; P < .001), be older in age (35.0 vs 29.9 years; P = .001), have a higher body mass index (27.2 vs 25.0; P = .001), and have a greater alpha angle (69.6° vs 62.3°; P < .001) compared with the nonmicrofracture cohort (n = 533). After propensity matching to control for covariates, patients treated with microfracture displayed no differences in the modified Harris Hip Score or Hip Disability and Osteoarthritis Outcome Score (P = .22-.95) but were more likely to undergo total hip arthroplasty (THA) (13% [7/54] compared with 4% [6/162] in the control group; P = .002), and age >35 years was associated with conversion to THA after microfracture. Microfracture performed at or before 35 years of age portended good outcomes with no significant risk of conversion to THA at the most recent follow-up. CONCLUSION: Microfracture of acetabular cartilage defects appears to be safe and associated with reliably improved short- to mid-term results in younger patients; modified expectations should be realized when full-thickness chondral lesions are identified in patients >35 years of age.

Enhanced Recovery After Surgery for an Uncommon Complex Urological Procedure: The Complete Primary Repair of Bladder Exstrophy.

PURPOSE: ERAS (enhanced recovery after surgery) protocols are designed to optimize perioperative care and expedite recovery. Historically, complete primary repair of bladder exstrophy has included postoperative recovery in the intensive care unit and extended length of stay. We hypothesized that instituting ERAS principles would benefit children undergoing complete primary repair of bladder exstrophy, decreasing length of stay. We describe implementation of a complete primary repair of bladder exstrophy-ERAS pathway at a single, freestanding children's hospital. MATERIALS AND METHODS: A multidisciplinary team developed an ERAS pathway for complete primary repair of bladder exstrophy, which launched in June 2020 and included a new surgical approach that divided the lengthy procedure into 2 consecutive operative days. The complete primary repair of bladder exstrophy-ERAS pathway was continuously refined, and the final pathway went into effect in May 2021. Post-ERAS patient outcomes were compared with a pre-ERAS historical cohort (2013-2020). RESULTS: A total of 30 historical and 10 post-ERAS patients were included. All post-ERAS patients had immediate extubation (P = .04) and 90% received early feeding (P < .001). The median intensive care unit and overall length of stay decreased from 2.5 to 1 days (P = .005) and from 14.5 to 7.5 days (P < .001), respectively. After final pathway implementation, there was no intensive care unit use (n=4). Postoperatively, no ERAS patient required escalation of care, and there was no difference in emergency department visits or readmissions. CONCLUSIONS: Applying ERAS principles to complete primary repair of bladder exstrophy was associated with decreased variations in care, improved patient outcomes, and effective resource utilization. Although ERAS has typically been utilized for high-volume procedures, our study highlights that an enhanced recovery pathway is both feasible and adaptable to less common urological surgeries.

Periacetabular Osteotomy for Symptomatic Acetabular Dysplasia in Patients ≥40 Years Old: Intermediate and Long-Term Outcomes and Predictors of Failure.

BACKGROUND: The Bernese periacetabular osteotomy (PAO) is controversial as a treatment for symptomatic acetabular dysplasia in patients ≥40 years of age. We conducted a retrospective study to evaluate the outcomes, measure the survival rate, and identify factors associated with PAO failure in patients ≥40 years of age. METHODS: We performed a retrospective study of patients ≥40 years of age undergoing PAO. Study eligibility criteria were met by 166 patients (149 women; mean age, 44 ± 3 years), and 145 (87%) were followed for ≥4 years after PAO. We used a Kaplan-Meier curve with right-censoring to calculate survivorship, with "failure" defined as either conversion to or recommendation for total hip arthroplasty or a Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain score of ≥10 at the most recent follow-up. We used simple logistic regression models to determine whether any preoperative characteristics were significantly associated with PAO failure. RESULTS: The median follow-up time was 9.6 years (range, 4.2 to 22.5 years). Sixty-one of 145 hips (42%, 95% confidence interval [CI] = 34% to 51%) experienced PAO failure during follow-up. The median survival time was 15.5 years (95% CI = 13.4 to 22.1 years). The median survival time was longer for hips with no or mild preoperative osteoarthritis: 17.0 years for Tönnis grade 0, 14.6 years for grade 1, and 12.9 years for grade 2. Higher preoperative Tönnis arthritis grades (p = 0.03) and worse WOMAC function scores (p < 0.001) were associated with an increased likelihood of failure. CONCLUSIONS: PAO is usually effective at improving function and is effective at preserving the hip in patients ≥40 years of age provided that they have good preoperative function and no or mild preoperative osteoarthritis (Tönnis grade 0 or 1). Patients who are ≥40 years old with advanced preoperative osteoarthritis (Tönnis grade 2) and those with poor preoperative dysfunction have a high risk of therapeutic failure after PAO. LEVEL OF EVIDENCE: Therapeutic Level IV . See Instructions for Authors for a complete description of levels of evidence.

Combined femoral and acetabular version and synovitis are associated with dGEMRIC scores in people with femoroacetabular impingement (FAI) syndrome.

This study sought to explore, in people with symptoms, signs and imaging findings of femoroacetabular impingement (FAI syndrome): (1) whether more severe labral damage, synovitis, bone marrow lesions, or subchondral cysts assessed on magnetic resonance imaging (MRI) were associated with poorer cartilage health, and (2) whether abnormal femoral, acetabular, and/or combined femoral and acetabular versions were associated with poorer cartilage health. This cross-sectional study used baseline data from the 50 participants with FAI syndrome in the Australian FASHIoN trial (ACTRN12615001177549) with available dGEMRIC scans. Cartilage health was measured using delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score sampled at the chondrolabral junction on three midsagittal slices, at one acetabular and one femoral head region of interest on each slice, and MRI features were assessed using the Hip Osteoarthritis MRI Score. Analyses were adjusted for alpha angle and body mass index, which are known to affect dGEMRIC score. Linear regression assessed the relationship with the dGEMRIC score of (i) selected MRI features, and (ii) femoral, acetabular, and combined femoral and acetabular versions. Hips with more severe synovitis had worse dGEMRIC scores (partial η2 = 0.167, p = 0.020), whereas other MRI features were not associated. A lower combined femoral and acetabular version was associated with a better dGEMRIC score (partial η2 = 0.164, p = 0.021), whereas isolated measures of femoral and acetabular version were not associated. In conclusion, worse synovitis was associated with poorer cartilage health, suggesting synovium and cartilage may be linked to the pathogenesis of FAI syndrome. A lower combined femoral and acetabular version appears to be protective of cartilage health at the chondrolabral junction.

Hip Osteoarthritis: Bench to Bedside Perspective.

Osteoarthritis is a major source of pain, disability, and economic cost worldwide. For nearly a century, there has been a debate about the causes of hip osteoarthritis and the role that structural abnormalities may play as a causative factor. Recent advances in open and minimally invasive techniques such as the periacetabular osteotomy, surgical hip dislocation and arthroscopic approaches have allowed us safe access into the joint to not only improve the abnormal bony structure and repair damaged tissue but also to gain clinical insights into the cause of joint damage. At present, structural abnormalities such as acetabular dysplasia and CAM deformities of the proximal femur are thought to be a major factor causing premature hip OA. Over the past 30 years, our understanding of the function and biology of articular cartilage has evolved from a relatively acellular lubricating cushion to a metabolically active tissue that can modulate its tissue composition in response to mechanical loading. Using advanced biochemical MR imaging technique called delayed Gadolinium Enhanced MRI of Cartilage (dGEMRIC), it has been shown that alteration in the mechanical environment of the hip with a pelvic osteotomy in acetabular dysplasia can alter the articular cartilage composition. This further demonstrates the importance of mechanics in development of joint damage and the potential for surgical correction to prevent or slow down the progression of OA.

Synthesis of biologically derived poly(pyrogallol) nanofibers for antibacterial applications.

Herein, we present the facile synthesis of poly(pyrogallol) biopolymers and their application as antibacterial agents. Pyrogallol is a class of phenolic compounds that can be found in various plants. Polymerization was performed by the auto-oxidation of pyrogallol under a hydrated condition. The microscopic image of poly(pyrogallol) shows a highly homogenous nanofibrous structure with a diameter of 100.3 ± 16.3 nm. Spectroscopic analysis by FT-IR spectroscopy, Raman spectroscopy, and XPS corroborated the formation of ether (C-O-C) bonds between the hydroxyl group and adjacent carbons of pyrogallol during polymerization. The FT-IR and XPS spectra also revealed redox-active gallol functional groups on poly(pyrogallol) nanofibers, which can be used to release free electrons and protons during oxidation followed by the generation of reactive oxygen species (ROS). The generated ROS from poly(pyrogallol) was used to inhibit the growth of bacteria, Escherichia coli, at a inhibition rates of 56.3 ± 9.7% and 95.5 ± 2.0% within 0.5 and 2 h, respectively. This finding suggests that poly(pyrogallol) can be used as a naturally occurring antibacterial agent for various biomedical and environmental applications.

Large Hip Impingement Area and Subspine Hip Impingement in Patients With Absolute Femoral Retroversion or Decreased Combined Version.

Background: It remains unclear if femoral retroversion is a contraindication for hip arthroscopy in patients with femoroacetabular impingement (FAI). Purpose: To compare the area and location of hip impingement at maximal flexion and during the FADIR test (flexion, adduction, internal rotation) in FAI hips with femoral retroversion, hips with decreased combined version, and asymptomatic controls. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Twenty-four symptomatic patients (37 hips) with anterior FAI were evaluated. All patients had femoral version (FV) <5° according to the Murphy method. Two subgroups were analyzed: 13 hips with absolute femoral retroversion (FV <0°) and 29 hips with decreased combined version (McKibbin index <20°). All patients were symptomatic and had anterior groin pain and a positive anterior impingement test ; all had undergone pelvic computed tomography (CT) scans to measure FV. The asymptomatic control group consisted of 26 hips. Dynamic impingement simulation of maximal flexion and FADIR test at 90° of flexion was performed with patient-specific CT-based 3-dimensional models. Extra- or intra-articular hip impingement area and location were compared between the subgroups and with control hips using nonparametric tests. Results: Impingement area was significantly larger for hips with decreased combined version (<20°) versus combined version (≥20°) (mean ± SD; 171 ± 140 vs 78 ± 55 mm2; P = .012) and was significantly larger for hips with FV <0° (absolute femoral retroversion) vs FV >0° (P = .025). Hips with absolute femoral retroversion had a significantly higher frequency of extra-articular subspine impingement versus controls (92% vs 0%; P < .001), compared to 84% of patients with decreased combined version. Intra-articular femoral impingement location was most often (95%) anterosuperior and anterior (2-3 o'clock). Anteroinferior femoral impingement location was significantly different at maximal flexion (anteroinferior [4-5 o'clock]) versus the FADIR test (anterosuperior and anterior [2-3 o'clock]) (P < .001). Conclusion: Patients with absolute femoral retroversion (FV <0°) had a larger hip impingement area, and most exhibited extra-articular subspine impingement. Preoperative FV assessment with advanced imaging (CT/magnetic resonance imaging) could help to identify these patients (without 3-dimensional modeling). Femoral impingement was located anteroinferiorly at maximal flexion and anterosuperiorly and anteriorly during the FADIR test.

Do Osteochondroplasty Alone, Intertrochanteric Derotation Osteotomy, and Flexion-Derotation Osteotomy Improve Hip Flexion and Internal Rotation to Normal Range in Hips With Severe SCFE? - A 3D-CT Simulation Study.

BACKGROUND: Severe slipped capital femoral epiphysis (SCFE) leads to femoroacetabular impingement and restricted hip motion. We investigated the improvement of impingement-free flexion and internal rotation (IR) in 90 degrees of flexion following a simulated osteochondroplasty, a derotation osteotomy, and a combined flexion-derotation osteotomy in severe SCFE patients using 3D-CT-based collision detection software. METHODS: Preoperative pelvic CT of 18 untreated patients (21 hips) with severe SCFE (slip-angle>60 degrees) was used to generate patient-specific 3D models. The contralateral hips of the 15 patients with unilateral SCFE served as the control group. There were 14 male hips (mean age 13±2 y). No treatment was performed before CT. Specific collision detection software was used for the calculation of impingement-free flexion and IR in 90 degrees of flexion and simulation of osteochondroplasty, derotation osteotomy, and combined flexion-derotation osteotomy. RESULTS: Osteochondroplasty alone improved impingement-free motion but compared with the uninvolved contralateral control group, severe SCFE hips had persistently significantly decreased motion (mean flexion 59±32 degrees vs. 122±9 degrees, P <0.001; mean IR in 90 degrees of flexion -5±14 degrees vs. 36±11 degrees, P <0.001). Similarly, the impingement-free motion was improved after derotation osteotomy, and impingement-free flexion after a 30 degrees derotation was equivalent to the control group (113± 42 degrees vs. 122±9 degrees, P =0.052). However, even after the 30 degrees derotation, the impingement-free IR in 90 degrees of flexion persisted lower (13±15 degrees vs. 36±11 degrees, P <0.001). Following the simulation of flexion-derotation osteotomy, mean impingement-free flexion and IR in 90 degrees of flexion increased for combined correction of 20 degrees (20 degrees flexion and 20 degrees derotation) and 30 degrees (30 degrees flexion and 30 degrees derotation). Although mean flexion was equivalent to the control group for both (20 degrees and 30 degrees) combined correction, the mean IR in 90 degrees of flexion persisted decreased, even after the 30 degrees combined flexion-derotation (22±22 degrees vs. 36 degrees±11, P =0.009). CONCLUSIONS: Simulation of derotation-osteotomy (30 degrees correction) and flexion-derotation-osteotomy (20 degrees correction) normalized hip flexion for severe SCFE patients, but IR in 90 degrees of flexion persisted slightly lower despite significant improvement. Not all SCFE patients had improved hip motion with the performed simulations; therefore, some patients may need a higher degree of correction or combined treatment with osteotomy and cam-resection, although not directly investigated in this study. Patient-specific 3D-models could help individual preoperative planning for severe SCFE patients to normalize the hip motion. LEVEL OF EVIDENCE: III, case-control study.

Limited External Rotation and Hip Extension Due to Posterior Extra-articular Ischiofemoral Hip Impingement in Female Patients With Increased Femoral Anteversion: Implications for Sports, Sexual, and Daily Activities.

BACKGROUND: Posterior femoroacetabular impingement (FAI) is poorly understood. Patients with increased femoral anteversion (FV) exhibit posterior hip pain. PURPOSE: To correlate hip impingement area with FV and with combined version and to investigate frequency of limited external rotation (ER) and hip extension (<40°, <20°, and <0°) due to posterior extra-articular ischiofemoral impingement. STUDY DESIGN: Cross-sectional study; Level of evidence, 3. METHODS: Osseous patient-specific three-dimensional (3D) models based on 3D computed tomography scans were generated of 37 female patients (50 hips) with positive posterior impingement test (100%) and increased FV >35° (Murphy method). Surgery was performed in 50% of patients (mean age, 30 years; 100% female). FV and acetabular version (AV) were added to calculate combined version. Subgroups of patients (24 hips) with increased combined version >70° and patients (9 valgus hips) with increased combined version >50° were analyzed. The control group (20 hips) had normal FV, normal AV, and no valgus. Bone segmentation was performed to generate 3D models of every patient. Validated 3D collision detection software was used for simulation of impingement-free hip motion (equidistant method). Impingement area was evaluated in combined 20° of ER and 20° of extension. RESULTS: Posterior extra-articular ischiofemoral impingement occurred between the ischium and the lesser trochanter in 92% of patients with FV >35° in combined 20° of ER and 20° of extension. Impingement area in combined 20° of ER and 20° of extension was larger with increasing FV and with higher combined version; correlation was significant (P < .001, r = 0.57, and r = 0.65). Impingement area was significantly (P = .001) larger (681 vs 296 mm2) for patients with combined version >70° (vs <70°, respectively) in combined 20° of ER and 20° of extension. All symptomatic patients with increased FV >35° (100%) had limited ER <40°, and most (88%) had limited extension <40°. The frequency of posterior intra- and extra-articular hip impingement of symptomatic patients (100% and 88%, respectively) was significantly (P < .001) higher compared with the control group (10% and 10%, respectively). The frequency of patients with increased FV >35° with limited extension <20° (70%) and patients with limited ER <20° (54%) was significantly (P < .001) higher compared with the control group (0% and 0%, respectively). The frequency of completely limited extension <0° (no extension) and ER <0° (no ER in extension) was significantly (P < .001) higher for valgus hips (44%) with combined version >50° compared with patients with FV >35° (0%). CONCLUSION: All patients with increased FV >35° had limited ER <40°, and most of them had limited extension <20° due to posterior intra- or extra-articular hip impingement. This is important for patient counselling, for physical therapy, and for planning of hip-preservation surgery (eg, hip arthroscopy). This finding has implications and could limit daily activities (long-stride walking), sexual activity, ballet dancing, and sports (eg, yoga or skiing), although not studied directly. Good correlation between impingement area and combined version supports evaluation of combined version in female patients with positive posterior impingement test or posterior hip pain.

Femoral impingement in maximal hip flexion is anterior-inferior distal to the cam deformity in femoroacetabular impingement patients with femoral retroversion : implications for hip arthroscopy.

AIMS: Femoroacetabular impingement (FAI) patients report exacerbation of hip pain in deep flexion. However, the exact impingement location in deep flexion is unknown. The aim was to investigate impingement-free maximal flexion, impingement location, and if cam deformity causes hip impingement in flexion in FAI patients. METHODS: A retrospective study involving 24 patients (37 hips) with FAI and femoral retroversion (femoral version (FV) < 5° per Murphy method) was performed. All patients were symptomatic (mean age 28 years (SD 9)) and had anterior hip/groin pain and a positive anterior impingement test. Cam- and pincer-type subgroups were analyzed. Patients were compared to an asymptomatic control group (26 hips). All patients underwent pelvic CT scans to generate personalized CT-based 3D models and validated software for patient-specific impingement simulation (equidistant method). RESULTS: Mean impingement-free flexion of patients with mixed-type FAI (110° (SD 8°)) and patients with pincer-type FAI (112° (SD 8°)) was significantly (p < 0.001) lower compared to the control group (125° (SD 13°)). The frequency of extra-articular subspine impingement was significantly (p < 0.001) increased in patients with pincer-type FAI (57%) compared to cam-type FAI (22%) in 125° flexion. Bony impingement in maximal flexion was located anterior-inferior at femoral four and five o'clock position in patients with cam-type FAI (63% (10 of 16 hips) and 37% (6 of 10 hips)), and did not involve the cam deformity. The cam deformity did not cause impingement in maximal flexion. CONCLUSION: Femoral impingement in maximal flexion was located anterior-inferior distal to the cam deformity. This differs to previous studies, a finding which could be important for FAI patients in order to avoid exacerbation of hip pain in deep flexion (e.g. during squats) and for hip arthroscopy (hip-preservation surgery) for planning of bone resection. Hip impingement in flexion has implications for daily activities (e.g. putting on shoes), sports, and sex.Cite this article: Bone Joint Res 2023;12(1):22-32.

Moderators, Mediators, and Prognostic Indicators of Treatment With Hip Arthroscopy or Physical Therapy for Femoroacetabular Impingement Syndrome: Secondary Analyses From the Australian FASHIoN Trial.

BACKGROUND: Although randomized controlled trials comparing hip arthroscopy with physical therapy for the treatment of femoroacetabular impingement (FAI) syndrome have emerged, no studies have investigated potential moderators or mediators of change in hip-related quality of life. PURPOSE: To explore potential moderators, mediators, and prognostic indicators of the effect of hip arthroscopy and physical therapy on change in 33-item international Hip Outcome Tool (iHOT-33) score for FAI syndrome. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Overall, 99 participants were recruited from the clinics of orthopaedic surgeons and randomly allocated to treatment with hip arthroscopy or physical therapy. Change in iHOT-33 score from baseline to 12 months was the dependent outcome for analyses of moderators, mediators, and prognostic indicators. Variables investigated as potential moderators/prognostic indicators were demographic variables, symptom duration, alpha angle, lateral center-edge angle (LCEA), Hip Osteoarthritis MRI Scoring System (HOAMS) for selected magnetic resonance imaging (MRI) features, and delayed gadolinium-enhanced MRI of cartilage (dGEMRIC) score. Potential mediators investigated were change in chosen bony morphology measures, HOAMS, and dGEMRIC score from baseline to 12 months. For hip arthroscopy, intraoperative procedures performed (femoral ostectomy ± acetabular ostectomy ± labral repair ± ligamentum teres debridement) and quality of surgery graded by a blinded surgical review panel were investigated for potential association with iHOT-33 change. For physical therapy, fidelity to the physical therapy program was investigated for potential association with iHOT-33 change. RESULTS: A total of 81 participants were included in the final moderator/prognostic indicator analysis and 85 participants in the final mediator analysis after exclusion of those with missing data. No significant moderators or mediators of change in iHOT-33 score from baseline to 12 months were identified. Patients with smaller baseline LCEA (ß = -0.82; P = .034), access to private health care (ß = 12.91; P = .013), and worse baseline iHOT-33 score (ß = -0.48; P < .001) had greater iHOT-33 improvement from baseline to 12 months, irrespective of treatment allocation, and thus were prognostic indicators of treatment response. Unsatisfactory treatment fidelity was associated with worse treatment response (ß = -24.27; P = .013) for physical therapy. The quality of surgery and procedures performed were not associated with iHOT-33 change for hip arthroscopy (P = .460-.665 and P = .096-.824, respectively). CONCLUSION: No moderators or mediators of change in hip-related quality of life were identified for treatment of FAI syndrome with hip arthroscopy or physical therapy in these exploratory analyses. Patients who accessed the Australian private health care system, had smaller LCEAs, and had worse baseline iHOT-33 scores, experienced greater iHOT-33 improvement, irrespective of treatment allocation.