Radiographic Findings Associated With Mild Hip Dysplasia in 3869 Patients Using a Deep Learning Measurement Tool.

Background: Hip dysplasia is considered one of the leading etiologies contributing to hip degeneration and the eventual need for total hip arthroplasty (THA). We validated a deep learning (DL) algorithm to measure angles relevant to hip dysplasia and applied this algorithm to determine the prevalence of dysplasia in a large population based on incremental radiographic cutoffs. Methods: Patients from the Osteoarthritis Initiative with anteroposterior pelvis radiographs and without previous THAs were included. A DL algorithm automated 3 angles associated with hip dysplasia: modified lateral center-edge angle (LCEA), Tönnis angle, and modified Sharp angle. The algorithm was validated against manual measurements, and all angles were measured in a cohort of 3869 patients (61.2 ± 9.2 years, 57.1% female). The percentile distributions and prevalence of dysplastic hips were analyzed using each angle. Results: The algorithm had no significant difference (P > .05) in measurements (paired difference: 0.3°-0.7°) against readers and had excellent agreement for dysplasia classification (kappa = 0.78-0.88). In 140 minutes, 23,214 measurements were automated for 3869 patients. LCEA and Sharp angles were higher and the Tönnis angle was lower (P < .01) in females. The dysplastic hip prevalence varied from 2.5% to 20% utilizing the following cutoffs: 17.3°-25.5° (LCEA), 9.4°-15.6° (Tönnis), and 41.3°-45.9° (Sharp). Conclusions: A DL algorithm was developed to measure and classify hips with mild hip dysplasia. The reported prevalence of dysplasia in a large patient cohort was dependent on both the measurement and threshold, with 12.4% of patients having dysplasia radiographic indices indicative of higher THA risk.

Persistently elevated joint contact stress after periacetabular osteotomy is associated with joint failure at minimum 10-year follow-up.

Periacetabular osteotomy (PAO) is a common treatment for prearthritic hip dysplasia. The goal of this investigation was to determine if computationally assessed hip contact mechanics are associated with joint failure at minimum 10-year follow-up. One hundred patients with hip dysplasia (125 hips) completed patient-reported outcomes an average of 13.8 years (range 10.0-18.0 years) after PAO. 63/125 hips were classified as having failed: 26 converted to total hip arthroplasty (THA) and 37 with significant disability indicated by modified Harris Hip Score (mHHS) ≤ 70. Differences in discrete element analysis-computed contact mechanics were compared between (1) preserved and failed hips, (2) preserved hips and hips that failed by THA, and (3) preserved hips and hips that failed by mHHS ≤ 70. Failed hips had significantly higher preoperative contact stress and exposure metrics (p < 0.001-0.009) than preserved hips. Failed hips also had significantly higher postoperative peak contact stress (p = 0.018), higher mean contact stress (p < 0.001), and smaller contact area (p = 0.044). When assessed based on type of failure, hips that failed by THA had significantly higher postoperative contact stress and exposure metrics than preserved hips (p < 0.001-0.020). In hips that failed by mHHS ≤ 70, mean postoperative contact stress exposure was significantly higher compared to preserved hips (p = 0.043). Despite improved radiographic measures of dysplasia after PAO, pathologic joint contact mechanics can persist and predict treatment failure at minimum 10 years after surgery. Operative and nonoperative techniques specifically intended to reduce harmful contact mechanics in dysplastic hips may have the potential to further improve clinical outcomes after PAO.

The role of different acetabular morphologies on patient-reported outcomes following periacetabular osteotomy in borderline hip dysplasia.

INTRODUCTION: The treatment option for borderline hip dysplasia (BHD) includes hip arthroscopy and periacetabular osteotomy (PAO). To the present day the controversial discussion remains, which intervention to prefer. Literature reports supporting an educated choice are scare, based on small patient cohorts and do not address the variability of acetabular morphology. Consequently, we intended to report PAO outcomes, from patients diagnosed with BHD, dependent on acetabular morphology, in a large patient cohort and aimed to define risk factors for poor clinical results and patient satisfaction. MATERIALS AND METHODS: A prospective monocentre study was conducted. Patients enrolled underwent PAO for symptomatic BHD (LCEA, 18°-25°). A total of 107 hips were included with 94 complete data sets were available for evaluation with a minimum follow-up of 1 year and a mean follow-up of 2.3 years. The mean age was 31 ± 8.2 years, and 81.3% were female. As the primary outcome measure, we utilized the modified Harris hip score (mHHS) with minimal clinically important change (MCID) of eight to define clinical failure. Results were compared after a comprehensive radiographic assessment distinguishing between lateral deficient vs. anterior/posterolateral deficient acetabular and stable vs. unstable hip joints. RESULTS: Overall, clinical success was achieved in 91.5% of patients and the mHHS improved significantly (52 vs. 84.7, p < 0.001). Eight hips failed to achieve the MCID and four had radiographic signs of overcorrection. Comparing variable joint morphologies, the rate of clinical success was higher in patients with an anterior/posterolateral deficient acetabular covarage compared to lateral deficient acetabular (95.2% vs. 90.4%). tThe highest rate of clinical failure was recorded in unstable hip joints (85.7% vs. 92.5% in stable hips). CONCLUSIONS: This study demonstrates that PAO is an effective means to treat symptomatic BHD with variable acetabular morphologies, achieving a clinical success in 91.5% of all patients. To maintain a high level of safety and patient satisfaction technical accuracy appears crucial.

Rehabilitation following periacetabular osteotomy for acetabular dysplasia: A qualitative interview study exploring challenges, hopes and expectations among patients in Denmark and Australia.

INTRODUCTION: Guidelines have been proposed for post-operative rehabilitation following periacetabular osteotomy (PAO). However, the perspectives of individuals undergoing PAO have not been considered. AIM: The present study aimed to explore the perceived challenges of everyday life and hopes for and expectations of post-PAO rehabilitation from the perspective of individuals with acetabular dysplasia living in Denmark and Australia. METHODS: In this qualitative study, we used a hermeneutic phenomenological approach with semi-structured interviews to explore the perspectives of 25 participants (four males), aged 16-43 years, who underwent a PAO. Purposeful sampling was used to provide variations in age and sex. Inclusion criteria were age above 15 years, radiographic evidence of acetabular dysplasia, PAO within the last seven weeks and undergoing post-operative rehabilitation. Inductive content analysis was adopted to code and analyse interviews. RESULTS: The analysis of the interview transcripts revealed four major themes: different expectations, self-confidence, tailored rehabilitation and aligning expectations. Several subthemes emerged within each theme, and similar patterns with minor variations were identified across countries. However, the financial burden of self-funded surgery and rehabilitation challenged some Australian participants, whereas none of the Danish participants mentioned this challenge. CONCLUSION: Our findings elucidate the diverse range of hopes and expectations in individuals undergoing PAO, and how these relate to their perceived challenges. In particular, the findings highlight the importance of aligning expectations between individuals and clinicians when designing the rehabilitation.

Predictive Factors for Intraoperative Determination for the Need of Femoral Osteochondroplasty After Periacetabular Osteotomy for Acetabular Dysplasia.

Background: Determination of need for osteochondroplasty (OCP) during periacetabular osteotomy (PAO) commonly relies on intraoperative assessment of internal rotation at 90° flexion (IRF). Performing an OCP helps decrease the risk of iatrogenic femoroacetabular impingement from PAO reduction. Avoiding impingement helps decrease risks of accelerated secondary osteoarthritis. The literature is limited for factors that predict need for OCPs during PAOs. The purpose of this study was to (1) define the characteristics of patients needing concurrent OCP and provide OCP rate based on IRF and femoral version and (2) identify predictive factors (clinical, radiographic) associated with need for OCP during PAO. As some surgeons determine need for OCP pre-operatively, predictive factors would aid decision making. Methods: This was a prospective cohort of 224 hips (207 patients) who underwent PAO for symptomatic acetabular dysplasia, of which 154 hips (69%) underwent OCP between years 2013 and 2017. Patients underwent OCP if they had restrictions in motion or impingement intra-operatively. Pre-operative factors such as age, sex, BMI, and CT findings were recorded that underwent univariate and multivariable analyses. Multivariable analysis found predictors that were described using odds ratios and 95% confidence intervals. IRF>30° and femoral version 10°-25° were used as the reference groups during categorical analysis. P-values ≤0.05 were considered significant. Results: Alpha angles >55° (OR= 2.20, CI: 1.08-4.52, p= 0.03), IRF≤20° (OR: 9.52, CI: 3.87-23.40, p<0.001), IRF >20°-30° (OR: 2.68, CI: 1.08-6.62, p=0.03), and femoral version <10° (OR: 5.26, CI: 1.09-25.30, p=0.04) were associated with increased odds of OCP. On continuous modeling, decreasing femoral version (OR: 1.07, CI: 1.02-1.12, p=0.002) and IRF (OR: 1.06, CI: 1.03-1.09, p<0.001) were associated with increased chance of OCP. For 5° changes, the chance of OCP increased by 40% (OR: 1.40, CI: 1.13-1.73, p=0.002) and 35% (OR: 1.35, IC: 1.16-1.57, p<0.001), respectively. Conclusion: Awareness of need for OCP may be valuable in peri-operative planning for these patients especially since some surgeons perform this technique arthroscopically before PAO. Factors associated with increased chances of OCP were alpha angles >55°, decreased IRF, and decreased femoral version. More studies in the future would help determine how OCP affects patient outcomes. Level of Evidence: III.

Roles of combined femoral and acetabular anteversion in pathological changes of hip dysplasia and hip reconstructive surgery.

Combined femoral and acetabular anteversion is the sum of femoral and acetabular anteversion, representing their morphological relationship in the axial plane. Along with the increasing understanding of hip dysplasia in recent years, numerous scholars have confirmed the role of combined femoral and acetabular anteversion in the pathological changes of hip dysplasia. At present, the reconstructive surgery for hip dysplasia includes total hip replacement and redirectional hip preservation surgery. As an important surgery index, combined femoral and acetabular anteversion have a crucial role in these surgeries. Herein, we discuss the role of combined femoral and acetabular anteversion in pathological changes of hip dysplasia, total hip replacement, and redirectional hip preservation surgery.

Dysplastic Hips Have Decreased Iliofemoral Ligament Thickness on Coronal Sequences in Magnetic Resonance Imaging: A Matched Cohort Analysis.

PURPOSE: To characterize hip capsule thickness on advanced imaging in patients with and without hip dysplasia and to also evaluate differences in capsular thickness between borderline and true dysplastic patients. METHODS: Patients evaluated by the senior author for concerns of hip pathology from June 2020 to June 2021 were queried and images reviewed to determine dysplasia status by lateral center edge angle (LCEA) ≤ 25 degrees. A group of non-dysplastic patients was identified and matched for age, sex, and body mass index (BMI). Hip capsular thickness was quantified using MRI. A sub-analysis was conducted to compare true dysplastic patients (LCEA < 20°) to borderline dysplastic patients (LCEAs between 20 - 25°). Analysis included independent samples t-tests, Chi-square tests, and multivariable regression. RESULTS: Eighty total patients were included, with a mean age of 31.8 ± 11.7 years, a mean BMI of 26.6 ± 6.5 points, and 70% (56) female patients. Dysplastic patients had a mean LCEA of 19.8 ± 4.3 degrees. Dysplastic individuals had decreased capsular thickness compared to their non-dysplastic controls (2.75 ± 0.96 vs 3.52 ± 1.22 mm, p = 0.003). Multivariable regression showed decreased capsular thickness associated with decreased LCEAs (ß = 2.804, R = 0.432, p<0.001) and dysplasia (ß = -0.709, R2 = 0.056, p = 0.004). Results of a sub-analysis of the dysplastic group examining differences between accepted definitions of borderline dysplasia and true dysplasia showed no significant differences in capsular thickness between the two groups (p = 0.379). CONCLUSIONS: Patients with hip dysplasia were found to have thinner iliofemoral ligaments in the coronal plane on magnetic resonance imaging on magnetic resonance imaging. Further investigation is needed to evaluate any potential implications with hip instability given the thinner hip capsule demonstrated in this study.

Peri-Operative Management of Periacetabular Osteotomy: A Report of Current Practices from the Anchor Group, Supporting Literature, and Areas for Future Investigation.

Background: Periacetabular osteotomy (PAO) is a well-established surgical treatment for hip dysplasia, but very few studies report the impact of peri-operative management strategies on early pain and function. The purpose of this study is to describe peri-operative management variability among a group of experienced surgeons and review the literature supporting these practice patterns. Methods: We surveyed 16 surgeons that perform PAO to document various aspects of peri-operative management at four stages: pre-operative, intra-operative, post-operative in the hospital, and at discharge. Our goal was to report current surgical pain management strategies, adjunct medications, type of anesthesia, deep venous thrombosis and heterotopic ossification prophylaxis strategies, initiation of physical therapy, and use of continuous passive motion (CPM). We reviewed current literature to identify studies supporting these perioperative strategies and identify knowledge gaps that would benefit from further investigation. Results: Of the 16 surgeons surveyed, 75% had been in practice greater than 10 years and most had not altered their post-operative protocol for more than 3 years. 15/16 surgeons felt that length of stay could be reduced at their institution with improved peri-operative pain management. 6/16 were considering or had already implemented outpatient PAO as a part of their practice. We found significant variability in the pain medications provided at all peri-operative stages. 14/16 utilized general anesthesia, and many utilized epidural or peripheral nerve blocks. 6/16 surgeons utilized surgical field block (also referred to as periarticular block). These surgeons advocated that surgical field block was an effective intervention with no/minimal complication risk. There is very little literature critically evaluating efficacy of these perioperative management strategies for PAO. Conclusion: There is significant practice variability in peri-operative management of PAO surgery. We report various strategies utilized by a group of experienced surgeons and review supporting literature. There are significant knowledge gaps in best surgical pain management strategies, adjunct medications, surgical field blocks, and use of CPM that need further investigation. Level of Evidence: IV.

Hip Dysplasia Treated With Periacetabular Osteotomy in Patients Over 40 Years Old: A Systematic Review.

Background: Hip dysplasia is a leading cause of hip osteoarthritis. While periacetabular osteotomy (PAO) is effective for relieving pain and dysfunction caused by hip dysplasia in adolescents and young adults, there is concern that patients over 40 years of age will have an increased risk of persistent dysfunction and need for total hip arthroplasty. Current available evidence for PAO in older adults is limited and there is no systematic review in the literature focusing on this topic. The current systematic review offers insight into the demographics, patient-reported outcome measure (PROM) scores, and hip survivorship from total hip arthroplasty in patients over 40 years older treated for hip dysplasia with PAO. Methods: The review was conducted under the guidelines for the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). Databases that were searched included PubMed, OVID Medline, SCOPUS, Embase, Cochrane Library, and clinicaltrials.gov. Studies were screened based on predetermined inclusion and exclusion criteria. Results: Five studies were included in this systematic review. Enrollment years were 1990-2013. In total, there were 335 hips with mean ages between 43.5-47.2 years. Mean follow up was 4-10.8 years. Most patients that underwent hip preservation had Tonnis osteoarthritis grade 0-1. There was contradicting evidence whether patients >40 years did better or worse compared to <40 years; although, most patients in the >40 years group had good outcomes after PAO. PAO survivorship ranged from 67-100% depending on the study. Complications ranged from 2-36% of cases depending on the study; although, none of these complications had lasting effects. Conclusion: Patients over 40 years old appear to have positive outcomes when treated for hip dysplasia with PAO, though these patients were likely selected for no to minimal osteoarthritis, high functional status, and good health. PAO should be considered for patients with hip dysplasia over 40 years old without hip arthritis, though we recommend very selective indications. Level of Evidence: II.

Prevalence of Radiographic Hip Dysplasia in the General Adult Population: A Systematic Review.

Background: Acetabular dysplasia has a wide range of prevalence reported in the literature. This variation is likely due to differences in the population under investigation and studies focusing on cohorts with hip pain and osteoarthritis. There are reports of radiographic hip dysplasia prevalence for adults without hip pain but there is no systematic review of these studies to document the incidence in the general population. The purpose of this systematic review was to provide a full summary of all studies that report prevalence of hip dysplasia in adults without hip pain. Methods: PRISMA guidelines were utilized as an outline for this systematic review. Articles were pulled from PubMed, OVID Medline, Embase, SCOPUS, Cochrane Central Register of Clinical Trials, and clinicaltrials.gov from their inception dates to 1/7/24. Studies were included if participants were asymptomatic and reported rates of prevalence. Results: Fourteen studies were included in this systematic review. There were 10,998 hips from 5,506 participants included in this analysis. The overall prevalence of radiographic hip dysplasia was 2.3%. Eight studies of 5,930 hips reported the prevalence of hip dysplasia by sex. The prevalence rate in these studies was 3.8% in females and 2.7% in males. Conclusion: Acetabular dysplasia based on radiographic measurements is relatively common in the general adult population. Furthermore, females have a higher prevalence rate when compared to males. It is important to recognize the incidence of hip dysplasia in the asymptomatic adult population as we recommend surgical treatment for patients who present with hip pain and dysplasia. Further studies should investigate the natural history of untreated and treated hip dysplasia. Level of Evidence: III.

Incidence and management of secondary deformities after megaendoprosthetic proximal femur replacement in skeletally immature bone sarcoma patients.

INTRODUCTION: Megaendoprosthetic reconstruction of bone defects in skeletally immature patients has led to the development of unique complications and secondary deformities not observed in adult patient cohorts. With an increasing number of megaendoprosthetic replacements performed, orthopedic oncologists still gain experience in the incidence and type of secondary deformities caused. In this study, we report the incidence, probable cause and management outcome of two secondary deformities after megaendoprosthetic reconstruction of the proximal femur: hip dysplasia and genu valgum. MATERIALS AND METHODS: Retrospective analysis of 14 patients who underwent primary and/or repeat reconstruction/surgery with a megaendoprosthetic proximal femur replacement between 2018 and 2022. RESULTS: Mean patient age was 9.1 years (range 4-17 years). Stress shielding was observed in 71.4%. Hip dislocation was the most frequent complication (50%). While four dislocations occurred without an underlying deformity, secondary hip dysplasia was identified in 58.3% (n = 7/12) of intraarticular resections and reconstructions, leading to dislocation in 71.4% (n = 5/7). A genu valgum deformity was observed in 41.6% (n = 5/12). The incidence of secondary hip dysplasia and concomitant genu valgum was 42.9% (n = 3/7). Triple pelvic osteotomy led to rebound hip dysplasia in two cases (patients aged < 10 years), whereas acetabular socket replacement led to stable hip joints over the course of follow-up. Temporary hemiepiphyseodesis was applied to address secondary genu valgum. CONCLUSIONS: Patients aged < 10 years were prone to develop secondary hip dysplasia and genu valgum following proximal femur replacement in this study. Management of secondary deformities should depend on remaining skeletal growth. Stress shielding was observed in almost all skeletally immature patients.

The Impact of Epidural Analgesia on Immobility and extended Hospital Stay After Periacetabular Osteotomy.

AIMS: Early mobilisation after periacetabular osteotomy (PAO) represents an important goal after surgery. The purpose of this study was to determine whether the use of epidural aznalgesia (EA) is associated with prolonged immobility and an increased length of stay (LOS) after PAO surgery. METHODS: From January 2022 to July 2023, the study included a cohort of 150 PAO procedures all performed by the same surgeon (SSA). Patients were categorized into two distinct groups: those who received epidural analgesia (EA) (79 PAOs) and those who did not receive EA (71 PAOs). "Ready for discharge" was defined as the ability to ascend and descend a standardized flight of stairs independently. Multivariable linear regression was used to identify additional factors influencing LOS after PAO. RESULTS: Patients in the EA group were ready for discharge 5.95 ± 2.09 days after surgery which was significantly longer than in the No EA group´s average of 4.18 days ± 2.5, (p < 0.001). While the reduction in the number of patients experiencing pulmonary embolism in the No EA group did not reach statistical significance, it still demonstrated a relevant decrease from two patients within the EA group (2.53%) to 0 (0%) in the No EA group. The active engagement of the surgeon in mobilising patients led to a substantial reduction in LOS, decreasing it from 5.81 ± 2.18 days to 2.2 ± 0.77 days (p < 0.001). Multivariable analysis revealed five independent factors influencing the LOS following PAO which included absence of EA, surgeon-led mobilisation within 24 h after surgery, postoperative hemoglobin levels, BMI, and prior experience with PAO surgery on the contralateral side. CONCLUSIONS: Opting against the use of EA in patients undergoing PAO is advisable, as it will result in extended postoperative immobility and the associated risks. Additionally, the active participation of the surgeon in the mobilisation process is strongly recommended.

Minimum 10-Year Survivorship of Uncemented Acetabular Reconstruction With Bulk Femoral Head Autografting in Crowe Type IV Developmental Hip Dysplasia.

BACKGROUND: In total hip arthroplasty (THA) for severe dislocations such as Crowe type IV developmental dysplasia of the hip (DDH), sufficient bone volume for stable fixation of the acetabular component can be achieved by placing a reinforcing bone graft prepared from the resected femoral head into the deficient acetabulum. The purpose of the current study was to examine the long-term survivorship of uncemented THA in conjunction with a bulk femoral head autograft in patients who have Crowe type IV DDH. METHODS: A total of 35 patients (42 hips) who have Crowe type IV DDH and underwent THA using uncemented cup fixation with bulk femoral head autografting were followed up for a mean period of 15.0 years (range, 10.0 to 20.0) postoperatively. Anteroposterior pelvic radiographs were used for measurements such as the horizontal coverage of the grafted bone and the center-edge angle. Kaplan-Meier survivorship analyses were performed with revision of the acetabular component as the endpoint. RESULTS: The Kaplan-Meier analysis indicated 15-year survival rates of 90.4%. The mean horizontal coverage of grafted bone was 46.1% (range, 23.7 to 66.0), and there were 16 cases with horizontal coverage of ≥ 50%. There was no difference in the appearance of a thin (< 1 mm) radiolucency line around the cup between cases with < 50% versus ≥ 50% of the horizontal coverage of grafted bone (4 versus 2 hips; P = .446). Trabecular bridging and remodeling were seen in all cases after mean periods of 4.1 and 9.0 months postoperatively, respectively. Trabecular reorientation was seen in 41 of 42 hips (97.6%) at a mean follow-up of 19.9 months. CONCLUSIONS: Acetabular reconstruction with femoral bulk bone grafting for Crowe type IV DDH resulted in high survival rates and was a good method to restore bone stock and obtain long-term fixation.

Lifetime cost of surgical treatment for canine hip osteoarthritis is less than conservative management in dogs under eight years of age.

OBJECTIVE: To determine the lifetime cost of 3 treatments for canine hip osteoarthritis: (1) conservative management, (2) femoral head and neck excision (FHNE), or (3) total hip replacement. We hypothesized that FHNE would be the least expensive treatment at all ages. SAMPLE: Cost estimates from 11 private and academic referral centers from 8 randomly chosen cities across the US. METHODS: Costs of surgeries were collected from practices in 8 US cities. The literature was used to determine expected postoperative costs. For conservative management, costs of pain medications and diet were obtained by use of online pharmacies. A 4.5% inflation adjustment was used for costs in subsequent years. RESULTS: For a dog aged 1 to 7 years, FHNE had the lowest lifetime cost. Total hip replacement had the second lowest cost until age 4, after which conservative management was lower. For dogs > 8 years, conservative management was the most cost-effective. CLINICAL RELEVANCE: For dogs presenting with clinical signs at or under 1 year of age, the perceived benefits of total hip replacement may not be financially prohibitive if lifetime cost of care is considered. Femoral head and neck excision was also less expensive than long-term conservative management. This can help veterinarians inform owners on costs of treatments over the lifetime of their pet. This type of analysis is limited to financial costs alone and does not account for differences in outcomes, as these are not well established. It should be expanded in the future as better data on outcomes and impacts of care become available.

The Otto Aufranc Award: Does Hip Arthroscopy at the Time of Periacetabular Osteotomy Improve the Clinical Outcome for the Treatment of Hip Dysplasia? A Multicenter Randomized Clinical Trial.

BACKGROUND: A periacetabular osteotomy (PAO) is often sufficient to treat the symptoms and improve quality of life for symptomatic hip dysplasia. However, acetabular cartilage and labral pathologies are very commonly present, and there is a lack of evidence examining the benefits of adjunct arthroscopy to treat these. The goal of this study was to compare the clinical outcome of patients undergoing PAO with and without arthroscopy, with the primary end point being the International Hip Outcome Tool-33 at 1 year. METHODS: In a multicenter study, 203 patients who had symptomatic hip dysplasia were randomized: 97 patients undergoing an isolated PAO (mean age 27 years [range, 16 to 44]; mean body mass index of 25.1 [range, 18.3 to 37.2]; 86% women) and 91 patients undergoing PAO who had an arthroscopy (mean age 27 years [range, 16 to 49]; mean body mass index of 25.1 [17.5 to 25.1]; 90% women). RESULTS: At a mean follow-up of 2.3 years (range, 1 to 5), all patients exhibited improvements in their functional score, with no significant differences between PAO plus arthroscopy versus PAO alone at 12 months postsurgery on all scores: preoperative International Hip Outcome Tool-33 score of 31.2 (standard deviation [SD] 16.0) versus 36.4 (SD 15.9), and 12 months postoperative score of 72.4 (SD 23.4) versus 73.7 (SD 22.6). The preoperative Hip disability and Osteoarthritis Outcome pain score was 60.3 (SD 19.6) versus 66.1 (SD 20.0) and 12 months postoperative 88.2 (SD 15.8) versus 88.4 (SD 18.3). The mean preoperative physical health Patient-Reported Outcomes Measurement Information System score was 42.5 (SD 8.0) versus 44.2 (SD 8.8) and 12 months postoperative 48.7 (SD 8.5) versus 52.0 (SD 10.6). There were 4 patients with PAO without arthroscopy who required an arthroscopy later to resolve persistent symptoms, and 1 patient from the PAO plus arthroscopy group required an additional arthroscopy. CONCLUSIONS: This randomized controlled trial has failed to show any significant clinical benefit in performing hip arthroscopy at the time of the PAO at 1-year follow-up. Longer follow-up will be required to determine if hip arthroscopy provides added value to a PAO for symptomatic hip dysplasia.

Semi-supervised learning in diagnosis of infant hip dysplasia towards multisource ultrasound images.

Background: Automated diagnosis of infant hip dysplasia is heavily affected by the individual differences among infants and ultrasound machines. Methods: Hip sonographic images of 493 infants from various ultrasound machines were collected in the Department of Orthopedics in Yangzhou Maternal and Child Health Care Service Centre. Herein, we propose a semi-supervised learning method based on a feature pyramid network (FPN) and a contrastive learning scheme based on a Siamese architecture. A large amount of unlabeled data of ultrasound images was used via the Siamese network in the pre-training step, and then a small amount of annotated data for anatomical structures was adopted to train the model for landmark identification and standard plane recognition. The method was evaluated on our collected dataset. Results: The method achieved a mean Dice similarity coefficient (DSC) of 0.7873 and a mean Hausdorff distance (HD) of 5.0102 in landmark identification, compared to the model without contrastive learning, which had a mean DSC of 0.7734 and a mean HD of 6.1586. The accuracy, precision, and recall of standard plane recognition were 95.4%, 91.64%, and 94.86%, respectively. The corresponding area under the curve (AUC) was 0.982. Conclusions: This study proposes a semi-supervised deep learning method following Graf's principle, which can better utilize a large volume of ultrasound images from various devices and infants. This method can identify the landmarks of infant hips more accurately than manual operators, thereby improving the efficiency of diagnosis of infant hip dysplasia.

Morphology of the dysplastic hip and the relationship with sex and acetabular version.

The dysplastic hip is characterized by incomplete coverage of the femoral head, resulting in increased risk of early osteoarthritis. The morphological variation of the hip joint is diverse and clear differences exist between females and males. The aim of this observational study was therefore to investigate the relationship between the morphology of the hip, sex, and hip dysplasia using a three-dimensional model. Statistical shape models of the combined femur and pelvic bones were created from bilateral hips of 75 patients. Using manual angle measurements and regression analysis, the characteristic shape differences associated with sex and hip dysplasia were determined. The model showed clear differences associated with sex and hip dysplasia. We found that the acetabular anteversion in females was significantly higher (p < 0.0001) than in males while no significant difference in acetabular anteversion was found between normal and dysplastic hips (p = 0.11). The model showed that decreased acetabular anteversion resulted in the appearance of the cross-over sign and the prominent ischial spine sign commonly associated with retroversion. Sex could be predicted with an area under the curve of 0.99 and hip dysplasia could be predicted with an area under the curve of ≥0.73. Our findings suggest that retroversion is a result of decreased anteversion of the acetabulum and is primarily associated with sex. This finding should be taken into account during the reorientation of the acetabulum in the surgical treatment of hip dysplasia.

Incidence of risk factors in developmental dysplasia of the hip: a retrospective study on 18,954 cases.

BACKGROUND: DDH is 1 of the most important causes of childhood disability. A diagnosis of instability can be made in the neonatal period via the Ortolani and Barlow manoeuvres. However, clinical examination, although highly specific, has poor sensitivity as compared to ultrasound. There is controversy between the necessity of universal screening for dysplasia of all newborns or selective screening reserved for those with clinical signs of instability or known risk factors of DDH. AIM: To analyse the risk factors of congenital hip dysplasia in a consecutive case series of children referred for diagnosis and treatment of DDH. MATERIALS AND METHODS: This was a cross-sectional study on infants consecutively examined between January 2000 and December 2019 at the Marino Ortolani Centre in Ferrara, Italy. The first 3 types on Graf's classification were considered physiological (1A, 1B, 2A+), while the last 6 pathological (2A-, 2B, 2C, 2D, 3, 4). RESULTS: 18,954 infants met the inclusion criteria and were therefore considered eligible for the study. Of these 18,954 infants, 56% (n = 10,629) were females and 44% (n = 8325) were males. According to Graf classification, 34.9% (n = 6621) were 1A, 52.7% (n = 9999) were 1B, 4.0% (n = 753) were 2A+, 2.5% (n = 478) were 2A-, 1.5% (n = 284) were 2B, 1% (n = 196) were 2C, 1.3% (n = 243) were 2D, 1% (n = 193) were 3 and 1.0% (n = 187) were 4. The most significant risk factor was the female gender (OR 5.36; 95% CI, 4.63-6.20) followed by a family history (OR 2.35; 95% CI, 2.08-2.65), then skeletal pathologies (OR 2.04; 95% CI, 1.21-3.42), oligohydramnios (OR 1.75; 95% CI, 1.44-2.13), and finally breech presentation (OR 1.42: 95% CI, 1.27-1.60). CONCLUSIONS: Based on our data, family history, musculoskeletal disease, oligohydramnios and breech presentation are the main risk factors for DDH development, as is the female sex.

Routine ultrasound screening for hip dysplasia in children with clubfoot is not supported.

PURPOSE: Despite the existence of guidelines for screening for developmental dysplasia of the hip (DDH), there remains controversy regarding the need for routine ultrasound screening for DDH in patients with clubfoot due to an unclear correlation between the two conditions. The purpose of this study is to determine whether ultrasound screening for DDH in this population improved the diagnostic accuracy of DDH over standard assessment for patient risk factors and physical exam. METHODS: This is a retrospective cross-sectional review of infants diagnosed with idiopathic clubfoot who underwent hip ultrasounds to assess for DDH as identified by keyword search in an institutional radiological database at a tertiary care paediatric hospital. Patient demographics, risk factors for DDH, physical exam findings, and ultrasound results were recorded. RESULTS: Of the 120 patients who met the inclusion criteria between 2003 and 2018, 8 had hip dysplasia confirmed on ultrasound (6.7%). All these patients either had known risk factors for hip dysplasia or had an abnormal physical exam finding suggestive of hip instability or dislocation as performed by an orthopaedic surgeon on their initial consultation. CONCLUSION: A detailed history to determine risk factors and a thorough physical exam are adequate to determine the need for hip ultrasound in infants with idiopathic clubfoot. Routine ultrasound screening of all patients with clubfoot is likely unnecessary and may pose a significant burden on the health care system.