Search

BACKGROUND: Femoroacetabular impingement syndrome (FAIS) is frequently treated arthroscopically with osteoplasty and labral repair. Surgical preferences vary in terms of equipment, technique, and postoperative protocol. Patient-reported outcome measures (PROMs) are valuable tools to assess outcomes across different institutions. PURPOSE: To compare PROMs after FAIS arthroscopy and evaluate the impact on postoperative outcomes with independent surgeons utilizing different surgical techniques and postoperative protocols. STUDY DESIGN: Cohort study; Level of evidence, 2. METHODS: Prospective data were collected from patients with a 2-year follow-up after arthroscopic FAIS treatment by 2 orthopaedic surgeons from different states, each attending different sports medicine fellowships. Patients were matched according to age, sex, and body mass index. Data included patient characteristics, surgical findings, and the Hip disability and Osteoarthritis Outcome Score (HOOS) preoperatively and 2 years postoperatively. Patients with revision surgery, concomitant procedures, or incomplete pre- and postoperative data were excluded. Surgeon A utilized interportal capsulotomy, capsular repair, all-suture anchors, and a postoperative hip brace. Surgeon B employed periportal capsulotomy without repair, polyether ether ketone suture anchors, and no brace. The 2 high-volume arthroscopists (>100 hips/year) performed osteoplasty and labral repair and used a large perineal post. Cohorts were analyzed with appropriate t tests, with significance set at P < .05. The percentage of patients achieving minimal clinically important difference (MCID) was calculated using Pearson chi-square tests. RESULTS: A total of 176 hips (100 women, 76 men) were included, with 88 matched patients from each institution. The mean age was 33.7 years and the body mass index was 26.3 kg/m2. Both cohorts significantly improved in all 5 HOOS subscales 2 years after surgery. When comparing the mean change in PROMs and the percentage of patients achieving the MCID, differences were only observed in the HOOS-Sports subscale (cohort A: 25.3 ± 29.7 vs cohort B: 34.3 ± 29.7; P = .048; MCID achieved in 57% of patients vs 76%; P = .01). CONCLUSION: This prospective cohort study on arthroscopic FAIS treatment indicates that matched patient cohorts from different institutions show similarly improved PROMs at 2 years. This study suggests consistent patient outcomes across sites despite geography, surgeon, training, surgical technique, implants, and postoperative protocol.

There is a strong association between total hip bone mineral density (THBMD) changes after 24 mo of treatment and reduced fracture risk. We examined whether changes in THBMD after 12 and 18 mo of treatment are also associated with fracture risk reduction. We used individual patient data (n = 122 235 participants) from 22 randomized, placebo-controlled, double-blind trials of osteoporosis medications. We calculated the difference in mean percent change in THBMD (active-placebo) at 12, 18, and 24 mo using data available for each trial. We determined the treatment-related fracture reductions for the entire follow-up period, using logistic regression for radiologic vertebral fractures and Cox regression for hip, non-vertebral, all (combination of non-vertebral, clinical vertebral, and radiologic vertebral) fractures and all clinical fractures (combination of non-vertebral and clinical vertebral). We performed meta-regression to estimate the study-level association (r2 and 95% confidence interval) between treatment-related differences in THBMD changes for each BMD measurement interval and fracture risk reduction. The meta-regression revealed that for vertebral fractures, the r2 (95% confidence interval) was 0.59 (0.19, 0.75), 0.69 (0.32, 0.82), and 0.73 (0.33, 0.84) for 12, 18, and 24 mo, respectively. Similar patterns were observed for hip: r2 = 0.27 (0.00, 0.54), 0.39 (0.02, 0.63), and 0.41 (0.02, 0.65); non-vertebral: r2 = 0.27 (0.01, 0.52), 0.49 (0.10, 0.69), and 0.53 (0.11, 0.72); all fractures: r2 = 0.44 (0.10, 0.64), 0.63 (0.24, 0.77), and 0.66 (0.25, 0.80); and all clinical fractures: r2 = 0.46 (0.11, 0.65), 0.64 (0.26, 0.78), and 0.71 (0.32, 0.83), for 12-, 18-, and 24-mo changes in THBMD, respectively. These findings demonstrate that treatment-related THBMD changes at 12, 18, and 24 mo are associated with fracture risk reductions across trials. We conclude that BMD measurement intervals as short as 12 mo could be used to assess fracture efficacy, but the association is stronger with longer BMD measurement intervals.

BACKGROUND: This study investigates the association between the Geriatric Nutritional Risk Index (GNRI), a measure of malnutrition risk, and 30-day postoperative complications following revision total hip arthroplasty (rTHA). METHODS: The American College of Surgeons National Surgical Quality Improvement Program database was queried for all patients ≥65 who underwent aseptic rTHA between 2015 and 2021. The final study population (n = 7119) was divided into 3 groups based on preoperative GNRI: normal/reference (GNRI >98) (n = 4342), moderate malnutrition (92 ≤ GNRI ≤98) (n = 1367), and severe malnutrition (GNRI 2 days (OR 1.98, P < .001), and periprosthetic fracture (OR 1.54, P = .020). Severe malnutrition was independently and significantly associated with sepsis (OR 3.67, P < .001), septic shock (OR 3.75, P = .002), pneumonia (OR 2.73, P < .001), urinary tract infection (OR 2.04, P = .002), deep vein thrombosis (OR 1.01, P = .001), pulmonary embolism (OR 2.47, P = .019), acute renal failure (OR 8.44, P = .011), blood transfusions (OR 2.78, P < .001), surgical site infection (OR 2.59, P < .001), nonhome discharge (OR 3.36, P < .001), readmission (OR 1.69, P < .001), unplanned reoperation (OR 1.97, P < .001), length of stay >2 days (OR 5.41, P < .001), periprosthetic fractures (OR 1.61, P = .015), and mortality (OR 2.63, P < .001). CONCLUSIONS: Malnutrition has strong predictive value for short-term postoperative complications and has potential as an adjunctive risk stratification tool for geriatric patients undergoing rTHA.

INTRODUCTION: Brace treatment is common to address radiological dysplasia in infants with developmental dysplasia of the hip (DDH); however, it is unclear whether bracing provides significant benefit above careful observation by ultrasound. If observation alone is non-inferior to bracing for radiological dysplasia, unnecessary treatment may be avoided. Therefore, the purpose of this study is to determine whether observation is non-inferior to bracing for infants with radiological dysplasia. METHODS AND ANALYSIS: This will be a multicentre, global, randomised, non-inferiority trial performed under the auspices of a global prospective registry for infants and children diagnosed with DDH. Patients will be included if they present with radiological dysplasia (centred hip, alpha angle 43-60°, percent femoral head coverage greater than 35% measured on ultrasound) of a clinically stable hip under 3 months old. Patients will be excluded if they present with clinical hip instability, have received prior treatment or have known/suspected neuromuscular, collagen, chromosomal or lower-extremity congenital abnormalities or syndromic-associated hip abnormalities. Patients will be enrolled and randomised to undergo observation alone or brace treatment with a Pavlik harness for a minimum of 6 weeks. Follow-up visits will occur at 6 weeks, 1 year and 2 years post-enrolment. The primary outcome will be the norm-referenced acetabular index measured on the 2-year radiograph with a 3° non-inferiority margin. A total of 514 patients will be included.The study is anticipated to start in April 2024 and end in September 2028.The primary outcome will be compared between arms with a mixed-effects model with a random intercept for study centre, and a single covariate for the treatment group. If the lower bound of the 95% CI lies within 3° of the mean, we will treat this as evidence for non-inferiority. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the lead sites ethics board (University of British Columbia, Childrens and Womens Research Ethics Board). Ethics approval will be obtained from the local ethics committees or institutional review boards at each institution prior to patient enrolment. It is intended that the results of this study shall be published in peer-reviewed journals and presented at suitable conferences. TRIAL REGISTRATION NUMBER: NCT05869851.

BACKGROUND: The polyarticular nature of Osteoarthritis (OA) tends to manifest in multi-joints. Associations between cartilage health in connected joints can help identify early degeneration and offer the potential for biomechanical intervention. Such associations between hip and knee cartilages remain understudied. PURPOSE: To investigate T1p associations between hip-femoral and acetabular-cartilage subregions with Intra-limb and Inter-limb patellar cartilage; whole and deep-medial (DM), deep-lateral (DL), superficial-medial (SM), superficial-lateral (SL) subregions. STUDY TYPE: Prospective. SUBJECTS: Twenty-eight subjects (age 55.1 ± 12.8 years, 15 females) with none-to-moderate hip-OA while no radiographic knee-OA. FIELD STRENGTH/SEQUENCE: 3-T, bilateral hip, and knee: 3D-proton-density-fat-saturated (PDFS) Cube and Magnetization-Prepared-Angle-Modulated-Partitioned-k-Space-Spoiled-Gradient-Echo-Snapshots (MAPSS). ASSESSMENT: Ages of subjects were categorized into Group-1 (≤40), Group-2 (41-50), Group-3 (51-60), Group-4 (61-70), Group-5 (71-80), and Group-6 (≥81). Hip T1p maps, co-registered to Cube, underwent an atlas-based algorithm to quantify femoral and acetabular subregional (R2-R7) cartilage T1p. For knee Cube, a combination of V-Net architectures was used to segment the patellar cartilage and subregions (DM, DL, SM, SL). T1p values were computed from co-registered MAPSS. STATISTICAL TESTS: For Intra-and-Inter-limb, 5 optimum predictors out of 13 (Hip subregional T1p, age group, gender) were selected by univariate linear-regression, to predict outcome (patellar T1p). The top five predictors were stepwise added to six linear mixed-effect (LME) models. In all LME models, we assume the data come from the same subject sharing the same random effect. The best-performing models (LME-modelbest) selected via ANOVA, were tested with DM, SM, SL, and DL subregional-mean T1p. LME assumptions were verified (normality of residuals, random-effects, and posterior-predictive-checks). RESULTS: LME-modelbest (Intra-limb) had significant negative and positive fixed-effects of femoral-R5 and acetabular-R2 T1p, respectively (conditional-R2 = 0.581). LME-modelbest (Inter-limb) had significant positive fixed-effects of femoral-R3 T1p (conditional-R2 = 0.26). DATA CONCLUSION: Significant positive and negative T1p associations were identified between load-bearing hip cartilage-subregions vs. ipsilateral and contralateral patellar cartilages respectively. The effects were localized on medial subregions of Inter-limb, in particular. EVIDENCE LEVEL: 1 TECHNICAL EFFICACY: Stage 1.

Exoskeletons have enormous potential to improve human locomotive performance1-3. However, their development and broad dissemination are limited by the requirement for lengthy human tests and handcrafted control laws2. Here we show an experiment-free method to learn a versatile control policy in simulation. Our learning-in-simulation framework leverages dynamics-aware musculoskeletal and exoskeleton models and data-driven reinforcement learning to bridge the gap between simulation and reality without human experiments. The learned controller is deployed on a custom hip exoskeleton that automatically generates assistance across different activities with reduced metabolic rates by 24.3%, 13.1% and 15.4% for walking, running and stair climbing, respectively. Our framework may offer a generalizable and scalable strategy for the rapid development and widespread adoption of a variety of assistive robots for both able-bodied and mobility-impaired individuals.

PURPOSE: Hip osteoarthritis (OA) is a major cause of pain and disability worldwide. Lack of effective therapies may reflect poor knowledge on its aetiology and risk factors, and result in the management of end-stage hip OA with costly joint replacement. The Worldwide Collaboration on OsteoArthritis prediCtion for the Hip (World COACH) consortium was established to pool and harmonise individual participant data from prospective cohort studies. The consortium aims to better understand determinants and risk factors for the development and progression of hip OA, to optimise and automate methods for (imaging) analysis, and to develop a personalised prediction model for hip OA. PARTICIPANTS: World COACH aimed to include participants of prospective cohort studies with ≥200 participants, that have hip imaging data available from at least 2 time points at least 4 years apart. All individual participant data, including clinical data, imaging (data), biochemical markers, questionnaires and genetic data, were collected and pooled into a single, individual-level database. FINDINGS TO DATE: World COACH currently consists of 9 cohorts, with 38 021 participants aged 18-80 years at baseline. Overall, 71% of the participants were women and mean baseline age was 65.3±8.6 years. Over 34 000 participants had baseline pelvic radiographs available, and over 22 000 had an additional pelvic radiograph after 8-12 years of follow-up. Even longer radiographic follow-up (15-25 years) is available for over 6000 of these participants. FUTURE PLANS: The World COACH consortium offers unique opportunities for studies on the relationship between determinants/risk factors and the development or progression of hip OA, by using harmonised data on clinical findings, imaging, biomarkers, genetics and lifestyle. This provides a unique opportunity to develop a personalised hip OA risk prediction model and to optimise methods for imaging analysis of the hip.

BACKGROUND: Opioid use after revision total hip arthroplasty (rTHA) has not been well characterized. The purpose of this study was to characterize preoperative, perioperative, and postoperative opioid use during rTHA. METHODS: Patients undergoing revision THA from 2010 to 2018 were screened for opioid use 3 months before revision surgery and tracked 24 months postoperatively. Patients were categorized as naïve or tolerant. Opioid prescriptions and average morphine milligram equivalents (MME) were compared between the two groups. RESULTS: One hundred twenty-four of 247 patients (50%) in the tolerant group averaged a preoperative MME of 23.7 mg/day. Postoperatively, tolerant patients received significantly higher daily MME at all time points, including at 3 months 31.4 versus 18.1 mg/day (P < 0.001), 6 months 19.9 versus 2.95 mg/day (P < 0.001), 12 months 14.3 versus 3.5 mg/day (P < 0.001), and 24 months 10.7 versus 2.17 mg/day (P < 0.001). Tolerant patients were more likely to have a prescription at 6 months (44% versus 22%), 12 months (41.4% versus 24%), and 24 months (38% versus 19.3%) (P < 0.001, P = 0.002, P < 0.001, respectively). DISCUSSION: Opioid-tolerant patients had higher postoperative MME requirements for longer recovery duration. Both groups reduced opioid use at 3 months and plateaued at 6 months. These findings can help the revision surgeon counsel patients and expectations.

Purpose: Distinguishing between Osteonecrosis of the femoral head (ONFH) and Osteoarthritis (OA) can be subjective and vary between users with different backgrounds and expertise. This study aimed to construct and evaluate several Radiomics-based machine learning models using MRI to differentiate between those two disorders and compare their efficacies to those of medical experts. Methods: 140 MRI scans were retrospectively collected from the electronic medical records. They were split into training and testing sets in a 7:3 ratio. Handcrafted radiomics features were harvested following the careful manual segmentation of the regions of interest (ROI). After thoroughly selecting these features, various machine learning models have been constructed. The evaluation was carried out using receiver operating characteristic (ROC) curves. Then NaiveBayes (NB) was selected to establish our final Radiomics-model as it performed the best. Three users with different expertise and backgrounds diagnosed and labeled the dataset into either OA or ONFH. Their results have been compared to our Radiomics-model. Results: The amount of handcrafted radiomics features was 1197 before processing; after the final selection, only 12 key features were retained and used. User 1 had an AUC of 0.632 (95% CI 0.4801-0.7843), User 2 recorded an AUC of 0.565 (95% CI 0.4102-0.7196); while User 3 was on top with an AUC of 0.880 (95% CI 0.7753-0.9843). On the other hand, the Radiomics model attained an AUC of 0.971 (95% CI 0.9298-1.0000); showing greater efficacy than all other users. It also demonstrated a sensitivity of 0.937 and a specificity of 0.885. DCA (Decision Curve Analysis displayed that the radiomics-model had a greater clinical benefit in differentiating OA and ONFH. Conclusion: We have successfully constructed and evaluated an interpretable radiomics-based machine learning model that could distinguish between OA and ONFH. This method has the ability to aid both junior and senior medical professionals to precisely diagnose and take prompt treatment measures. [ABSTRACT FROM AUTHOR]

The main method for large-scaled preparing powder superalloys in the production process is inert gas atomization, particularly vacuum-induced gas atomization (VIGA). A novel technique called electrode-induced gas atomization (EIGA) with a crucible-free electrode was proposed to prepare non-inclusion superalloy powders. In this study, a Ni-based superalloy of FGH4096 powder was prepared using both the VIGA and EIGA methods, while blanks were prepared through direct hot isostatic pressing (as-HIPed) near-net-forming method. The particle size, morphology, microstructure, and mechanical properties of the powders and blanks were compared via a laser particle size analyzer, SEM, TEM, and room-temperature and 650 °C tensile tests. The results indicated that EIGA-prepared powders exhibited a finer particle size and better surface quality than the one prepared via VIGA, which showed reduced satellite powders. However, the as-HIPed blank of EIGA-prepared powders had a lower secondary γ' ratio and slightly reduced strength compared to the as-HIPed blank of VIGA-prepared powders due to its slightly lower secondary γ' phase ratio and less effective inhibition of dislocation movement. Furthermore, the overall performance of the two samples did not differ significantly due to the similar microstructural characteristics of the powders. However, the variation in particle size affects heat conduction during the HIP process, resulting in slight differences in blanks' properties. [ABSTRACT FROM AUTHOR]

Purpose: To determine if difference in Hounsfield Units (HU) of the medullary bone between the injured and non-injured femurs in patients with greater trochanteric fractures is associated with occult intertrochanteric (IT) extension. Methods: Retrospective review was performed of 81 patients (age range 54–102, 54 females and 27 males) who underwent CT and subsequent MRI after identification of a greater trochanteric fracture without evidence of IT extension on radiography and/or CT. Hounsfield units of the injured and non-injured femurs on CT were recorded at the level of the base of the greater trochanter centrally (ROI1) and the level of the upper border of the lesser trochanter posteromedially (ROI2). The difference between the injured and non-injured femur for each ROI1 and ROI2 were calculated. Absence or presence, and if present, extent of IT extension was assessed on MRI. Analysis was performed to determine if there is correlation of difference in density with presence, and extent of occult IT fractures. Results: 81 cases met inclusion criteria, 14 (17%) had no IT extension, 11 (14%) had less than 50% IT extension and 56 (69%) had 50% or greater IT extension. There was statistical significance between presence and absence of IT extension between the injured and non-injured femur for ROI1 (HU) no IT extension median (IQR): 18.8(4–40), ROI1 (HU) present IT extension median (IQR): 65.5(46–90) p <.0001, and for ROI2 no IT extension median (IQR): 3(-8-25.5) and ROI2 present IT extension 51(40.5–76), p <.0001. There was statistical significance of the extent of IT extension: ROI1 less than 50% IT extension median (IQR): 37.5(27.5–57), ROI1 50% or greater IT extension median (IQR): 72.3(53.5–91.3), p <.0001, and for ROI2 less than 50% IT extension median (IQR): 17.5(8–49), and ROI2 50% or greater IT extension median (IQR): 55.8(45.3–81.5), p <.0001. A threshold ROI2 difference of 50 HU resulted in specificity of 92% and sensitivity 60.7% of for IT extension 50% or greater. Conclusion: Patients presenting with greater trochanteric fractures, an asymmetric increased density measured by ROI differences within the medullary space of the IT region between the injured and non-injured femur is associated with occult IT extension. [ABSTRACT FROM AUTHOR]