Hip Dysplasia in the Young Adult

Atypical presentation of ACCES syndrome resembling dominant Spondyloepiphyseal dysplasia tarda

Aplasia Cutis Congenita with Ectrodactyly Skeletal Syndrome (ACCES, OMIM #619959) is an extremely rare multiple congenital anomalies syndrome caused by haploinsufficiency of the UBA2 gene. This syndrome presents with growth retardation, dysmorphic facial features, neurodevelopmental delay, skeletal problems including ectrodactyly, developmental dysplasia of the hip (DDH) and scoliosis, skin findings such as aplasia cutis, and some internal organ abnormalities. Our 13-year-old female patient and her 38-year-old father had a skeletal dysplasia phenotype with disproportionate short stature, bilateral DDH, mild epiphyseal involvement, scoliosis, and increased lumbar lordosis. Both were neurodevelopmentally normal and had mild dysmorphic facial features and mild ectodermal findings. The dominant inheritance pattern in the pedigree suggested a pre-diagnosis of spondyloepiphyseal dysplasia tarda. The exome sequencing analysis of the patient has identified a novel heterozygous variant, NM_005499.2:c.460-2A >G, in the UBA2 gene, and the father was found heterozygous either. The isolated spondyloepiphyseal involvement of our patients was an unusual presentation compared to patients with ACCES syndrome previously reported in the literature. Considering the highly variable expressiveness of ACCES syndrome and the co-occurrence of familial hip dysplasia and vertebral problems, we suggest that this syndrome can also be classified under "Spondyloepi(meta)physial dysplasia (SE(M)D)" in the nosology of genetic skeletal disorders.

Two genetic variants in the HIBCH and FTCDNL1 genes are associated with susceptibility to developmental dysplasia of the hips among the Han Chinese population of Southwest China

BACKGROUND

Developmental dysplasia of the hip (DDH) is a common cause of childhood disability, and the incidence of DDH shows significant familial aggregation. As the genetic factors of DDH remain unknown, the correlation between five candidate single nucleotide polymorphisms (SNPs) and DDH was evaluated in the Han Chinese population of Southwest China.

METHODS

A case‒control association study was conducted in 276 patients with DDH and 318 healthy controls. SNP genotyping in the case and control groups was performed by SNPshot and multiple PCR. SNPs were genotyped in the case and control groups by multiplex PCR. The relationship between DDH and candidate SNPs was evaluated using the χ2 test.

RESULTS

The genotype distributions of rs291412 in HIBCH and rs769956 in FTCDNL1 were different between the case and control groups (P < 0.05). After genetic model analysis, logistic regression analysis revealed that the C allele of rs291412 had a protective effect on DDH (OR = 0.605, P = 0.010) and that the G allele of rs769956 was a risk factor (OR = 2.939, P = 0.010).s.

CONCLUSION

These SNPs could be associated with susceptibility to DDH but larger population-based studies should confirm the current results.

Integrated Acetabular Prosthesis Versus Bone Grafting in Total Hip Arthroplasty for Crowe Type II and III Hip Dysplasia: A Retrospective Case-Control Study

OBJECTIVE

Many methods of acetabular reconstruction with total hip arthroplasty (THA) for Crowe type II and III adult developmental dysplasia of the hip (DDH) acetabular bone defect have been implemented clinically. However, there was no study comparing the results of integrated acetabular prosthesis (IAP) with bone grafting (BG). This study aims to investigate the efficacy of IAP and BG for acetabular reconstruction in Crowe type II and III DDH.

METHODS

The clinical data of 45 patients with unilateral Crowe type II and III DDH who underwent THA from January 2020 to January 2023 were retrospectively analyzed. The patients were divided into two groups: 25 patients using 3D-printed IAP (IAP group) and 20 patients using BG (BG group). The operation time and intraoperative blood loss were recorded. The clinical outcomes were assessed by Harris Hip Score (HHS) and full weight-bearing time. The radiological outcomes were evaluated by the radiological examination. Accordingly, intraoperative and postoperative complications were observed as well. The data between the two groups were compared by independent sample t-tests and the Mann-Whitney U rank sum test.

RESULTS

There were no significant differences between the two groups in Harris Hip Score (HHS) (preoperative, 6 months postoperative, and the last follow-up), leg length discrepancy (LLD), cup inclination, cup anteversion, vertical center of rotation (V-COR), horizontal center of rotation (H-COR) (p > 0.05). The mean HHS in the IAP group was higher than in the BG group at 1 and 3 months postoperative (p < 0.001). The mean surgical time and blood loss in the IAP group were less than in the BG group (p < 0.001). The mean full weight-bearing time in the IAP group was shorter than in the BG group (p < 0.01). No complications were observed in either group during the follow-up period.

CONCLUSION

IAP and BG have similar radiographic outcomes and long-term clinical efficacy in THA for Crowe type II and III DDH, but the IAP technique has higher surgical safety and facilitates the recovery of hip joint function, which is worthy of clinical promotion.

Can We Enhance Shared Decision-making for Periacetabular Osteotomy Surgery? A Qualitative Study of Patient Experiences

BACKGROUND

Periacetabular osteotomy (PAO) surgery presents an opportunity for shared decision-making (SDM) and may be facilitated by decision-making tools. Currently, no diagnosis or treatment-specific decision-making tools exist for this patient population. Understanding patient PAO surgery decision-making experiences and processes would enable development of a treatment-specific decision-making tool and would help hip preservation surgeons with SDM practices.

QUESTIONS/PURPOSES

Qualitative methodology was used to address the following questions: (1) What were the information support needs of adult patients with hip dysplasia who decided to have PAO? (2) What was important to adult patients with hip dysplasia who decided to have PAO? (3) How did adult patients with hip dysplasia who have undergone PAO experience the surgical decision-making process? (4) What elements of SDM did adult patients with hip dysplasia experience with their surgeons when deciding to have PAO?

METHODS

Fifteen volunteer, English-speaking patients in the United States who had been diagnosed with hip dysplasia and who had undergone PAO surgery 6 to 12 months prior to the study were recruited through five PAO surgery Facebook support groups. Individuals were excluded if they had an underlying neuromuscular condition or other diagnosis related to nondevelopmental dysplasia of the hip or if they had a previous PAO surgery > 12 months before data collection. We used purposive sampling strategies to promote sample heterogeneity based on age and preoperative activity level, as these are characteristics that may impact decision-making. Participants were categorized into three age groups: 20 to 29 years, 30 to 39 years, and ≥ 40 years. Participants were also categorized as having "low activity," "moderate activity," or "high activity" preoperatively based on self-reported University of California Los Angeles (UCLA) Activity Scale scores. Participants were enrolled consecutively if they met the inclusion criteria and fulfilled one of our sampling categories; we had plans to enroll more participants if thematic saturation was not achieved through the first 15 interviews. Participants included 14 women and one man ranging in age from 23 to 48 years, and all had undergone PAO surgery for hip dysplasia 6 to 12 months prior to the interview. One-on-one semistructured interviews were conducted with each participant by a single interviewer through Zoom video conferencing using video and audio recording. Participants answered semistructured interview questions and provided verbal responses to survey questions so researchers could gain demographic information and details about their symptoms, diagnosis, and PAO surgery between June 2021 and August 2021. Quantitative survey data were analyzed using descriptive statistics. Qualitative data were analyzed by three researchers using principles of reflexive thematic analysis. Candidate themes were iteratively defined and redefined until central themes were developed that were distinctly different, yet centrally relevant, and answered the research questions. All codes that informed category and theme development were generated within the first six transcripts that were analyzed. The team felt that thematic saturation was established with the 15 interviews.

RESULTS

The main information needs for adult patients with hip dysplasia included diagnosis and treatment-related information, as well as logistics related to surgery and recovery. Many patients described that their information needs were only partially met by their surgeon; most engaged in additional information-seeking from scientific research and online resources and relied on patient peers to meet information needs about the lived experience and logistics related to surgery and recovery. It was important to patients that PAO surgery could preserve their native hip or delay THA and that PAO surgery was likely to reduce their pain and improve function; decision-making was facilitated when patients were able to identify how the indications and goals of PAO surgery aligned with their own situation and goals for surgery. Patients' experiences with decision-making were more positive when information needs were met, when indications and goals for PAO surgery aligned with their personal values and goals, and when their preferred and actual decision-making roles aligned. Adult patients with hip dysplasia described high variability in the extent to which patients were invited to share personal preferences, values, and goals around PAO surgery and the extent to which preferred patient decision-making roles were assessed.

CONCLUSION

We found that elements of SDM are not consistently integrated into hip preservation practice. The knowledge gained through this work about patient PAO surgery information needs, what matters to patients when deciding to have surgery, and their experiences with PAO surgery decision-making can inform future PAO surgery decision-making tool development. Future studies are needed to validate the findings of this study and to determine whether they are generalizable to adult patients with hip dysplasia with different demographic characteristics or to patients who do not participate in social media support groups.

CLINICAL RELEVANCE

Surgeons should recognize that patients are likely to leave their office without their information needs being met. SDM strategies can promote more effective information exchanges in the clinic so surgeons can help patients identify their information needs, provide education and direction to accurate and reputable resources to meet those needs, and help patients appraise information they gather and apply it to their personal situation. Hip preservation surgeons can use the sample SDM script and checklist offered here to support adult patients with hip dysplasia who are making PAO surgery decisions until a future diagnosis and treatment-specific decision-making tool is available.

Femurs in patients with hip dysplasia have fundamental shape differences compared with cam femoroacetabular impingement

Femoral deformities are common in developmental dysplasia of the hip (DDH), but decisions about how to treat them are not standardized. Of interest are deformities that may be akin to cam femoroacetabular impingement (FAI). We used three-dimensional and two-dimensional measures to clarify the similarities and differences in proximal femur shape variation among female patients with DDH (n = 68) or cam FAI (n = 60). Three-dimensional measures included femoral head asphericity, as well as shape variation using statistical shape modeling and principal component analysis (PCA). Two-dimensional measures included the α-angle, head-neck offset (HNO) and the neck-shaft angle (NSA). Significant shape variations were captured in the first five PCA modes, with the greatest shared variation between groups being the length from the lesser trochanter to the femoral head and greater trochanter height. Variations unique to DDH were irregularities at different areas of the femoral head, but not at the lateral femoral head-neck junction where variation was strong in FAI. The FAI group also had unique variations in greater trochanter shape. DDH femoral heads were less spherical, as indicated by larger sphere-fitting errors (P < 0.001). Radiographically, the DDH group had significantly smaller α-angles (P < 0.001), larger head-neck offsets (P = 0.02) and larger NSAs (P < 0.001). Both the articular and extra-articular regions of the proximal femur have distinct shape features in DDH and cam FAI that can uniquely affect the biomechanics of each disorder. Accordingly, approaches to addressing each disorder should be unique.

Maintenance of acetabular correction following PAO: a multicenter study comparing stainless-steel and titanium screws

Stainless-steel screws are commonly used for fragment fixation during periacetabular osteotomy (PAO) at our institutions. Titanium is reserved for patients with documented nickel allergies. Titanium screws possess a significantly lower Young's modulus than stainless steel and, therefore, potentially less resistance to physiologic loading. Thus, we hypothesized that the use of titanium screws might be associated with changes in acetabular correction prior to healing. The aim of this study was to compare the maintenance of acetabular correction following PAO using stainless-steel or titanium screws. A documented nickel allergy was confirmed with an allergy specialist. Patients' age at surgery, gender and BMI were collected. The lateral center-edge angle of Wiberg (LCEA), medial center-edge angle (MCEA), anterior wall index (AWI), posterior wall index (PWI) and Tönnis angle were measured. The delta value for radiographic parameters was calculated as the difference between values immediately post-operation and at 6 months post-operation. Only age at surgery (P < 0.001) and the pre-operative LCEA (P = 0.013) were significantly different between groups (Tables I and II). The remaining pre- and post-operative radiological measurements were similar (Table II). Comparison of delta values at 6 months follow-up indicated no significant differences between screw types (Table III). No patients in the titanium group had a trans-iliac retrograde screw included in their construct (P = 0.003). All patients healed from their osteotomies. The use of titanium screws in patients with an allergy to nickel was not associated with differences in acetabular correction or the rate of osseous union rates despite its lower inherent mechanical properties.

Total Hip Replacement and Femoral Nail Lengthening for Hip Dysplasia and Limb Length Discrepancy: A Literature Review

Developmental dysplasia of the hip (DDH) is a serious condition resulting in inadequate acetabular development, distorted bone configuration, and substantially altered hip biomechanics. An extensive leg length discrepancy (LLD) is commonly encountered in such cases, making a total hip arthroplasty (THA) procedure extremely challenging. Although good results in terms of patients' satisfaction, implant survival rates and overall improved quality of life have been reported, complication rates are considerably higher than primary THA procedures performed for idiopathic osteoarthritis. Reconstructing a dysplastic hip arthrosis and equalizing a preexisting LLD is a technically demanding procedure that is associated with significant bone and soft tissue complications. Intramedullary lengthening through motorized nails has become increasingly popular to address difficult cases with extensive LLD following THA in recent years. However, limited data on femoral lengthening procedures implemented following THA are available considering complications, radiological results, and patient-reported outcomes following staged THA and subsequent femoral lengthening using a femoral magnetically-driven intramedullary lengthening nail. We performed a literature review of the past 10 years in PubMed using the terms neglected hip dislocation, DDH, THA, and intramedullary lengthening nail as keywords. A total amount of eight cases addressing LLD through a telescoping intramedullary nail following THA in DDH have been reported in recent literature. All eight patients underwent primary THA for DDH followed by the implantation of the intramedullary lengthening nail. The mean THA was lengthened by 28.9 mm (from 13.0 to 45.0). The mean time for nail implantation after THA was 11.1 months (from 3.5 to 21). The mean time for lengthening per day through the nail was 0.94 mm (from 0.65 to 1.0) from 26 days to 70 days, and the mean lengthening through the nail was 37.6 mm (from 24.0 to 70.0). Good union and consolidation rates were reported by the authors, while there were no complications. The intramedullary distraction osteogenesis method with a telescopic rod can be an effective method to manage leg length discrepancies while avoiding soft tissue complications in challenging cases of DDH.

Staged Hip Arthroscopy with Labral Repair, Femoroplasty, and Capsular Plication Followed by Periacetabular Osteotomy for Hip Dysplasia Results in Improved Outcomes and 100% Survivorship at Minimum 2-Year Follow-Up

PURPOSE

To assess patient-reported outcomes (PROs), clinically significant outcomes (CSOs), and survivorship following staged hip arthroscopy with labral repair, femoroplasty, and capsular plication followed by periacetabular osteotomy (PAO) for the management of femoroacetabular impingement syndrome (FAIS) and hip dysplasia (lateral center edge angle ≤25°).

METHODS

A prospectively maintained database was queried to retrospectively identify patients who underwent staged primary hip arthroscopy and PAO between 1/2018-10/2021 and had a minimum 2-year follow-up. PROs collected included, Hip Outcome Score Activities of Daily Living/Sports Subscale (HOS-ADL/SS), international Hip Outcome Tool-12 item questionnaire (iHOT-12), and Visual Analog Scale for Pain (VAS Pain). CSO achievement for minimal clinical important difference (MCID) and patient acceptable symptom state (PASS) were determined through cohort specific thresholds. Rates of reoperation, including, revision hip arthroscopy and conversion to total hip arthroplasty (THA) were evaluated to determine short-term survivorship.

RESULTS

Thirty-nine hips met criteria for inclusion, of which 35 hips had minimum 2-year follow up (89.7% compliance). Mean age was 25±9.1 years and 91.7% of patients were female. Respective pre- and postoperative radiographic outcomes were: Alpha angle 59.8±5.9 to 39.7±2.6°, Tönnis angle 14.6±5.6° to -1.0±2.9°, lateral center-edge angle 16.6±5.5° to 36.6±4.6°, and anterior center-edge angle 15.6±9.1° to 36.1±3.8°, with statistically significant differences pre- to postoperatively for all (P<0.001). Patients demonstrated significant improvement in all PROs pre- to postoperatively (P ≤0.004). MCID and PASS achievement rates for any PRO were 93.9% and 78.8%, respectively. There were no revision hip surgeries or conversion to THA at a mean 2.7±1.0-year follow-up. Four patients (11.1%) underwent hardware removal. One patient (2.8%) experienced a postoperative infection treated with incision and drainage.

CONCLUSIONS

Staged hip arthroscopy and PAO for the management of hip dysplasia demonstrated improvement in PROs, high CSO achievement rates, and 100% survivorship at minimum 2-year follow-up.

Total Hip Arthroplasty With Subtrochanteric Osteotomy for Crowe IV Dysplasia Using an Extensile Direct Anterior Approach: A Surgical Technique

The direct anterior approach (DAA) has been increasing in popularity for primary total hip arthroplasty (THA). Despite previously documented anatomic limitations to its direct distal extension, alternative exposure methods have been described to safely access the femoral diaphysis and facilitate increasingly complex primary and revision THA scenarios. The DAA has several purported advantages compared to alternative approaches (eg, posterior and lateral-based), including its muscle-sparing nature, use of an internervous plane, and preservation of posterior stabilizing structures. Proponents of the DAA cite decreased postoperative pain, quicker recovery times, potentially lower dislocation rates, ease of intraoperative fluoroscopy, and improved implant placement/restoration of leg lengths. The current literature, however, is sparse when considering the use of this approach in the setting of severely dysplastic hips necessitating a concurrent subtrochanteric shortening osteotomy. When utilizing a posterior approach in this population, previous work from Ollivier and colleagues demonstrated high rates of cementless implant osseointegration and significantly improved clinical outcomes at long-term follow-up. Although relatively few reports of addressing this pathology via the DAA currently exist, initial results are promising. This study seeks to provide a detailed description of a surgical technique for performing primary THA and ipsilateral subtrochanteric shortening osteotomy in this patient population utilizing an extensile DAA.

Distinctiveness of Femoral and Acetabular Mesenchymal Stem and Progenitor Populations in Patients with Primary and Secondary Hip Osteoarthritis Due to Developmental Dysplasia

Primary hip osteoarthritis (pOA) develops without an apparent underlying reason, whereas secondary osteoarthritis arises due to a known cause, such as developmental dysplasia of the hips (DDH-OA). DDH-OA patients undergo total hip arthroplasty at a much younger age than pOA patients (50.58 vs. 65 years in this study). Recently, mesenchymal stem and progenitor cells (MSPCs) have been investigated for the treatment of osteoarthritis due to their immunomodulatory and regenerative potential. This study identified cells in subchondral bone expressing common MSPC markers (CD10, CD73, CD140b, CD146, CD164, CD271, GD2, PDPN) in vivo and compared the proportions of these populations in pOA vs. DDH-OA, further correlating them with clinical, demographic, and morphological characteristics. The differences in subchondral morphology and proportions of non-hematopoietic cells expressing MSPC markers were noted depending on OA type and skeletal location. Bone sclerosis was more prominent in the pOA acetabulum (Ac) in comparison to the DDH-OA Ac and in the pOA Ac compared to the pOA femoral head (Fh). Immunophenotyping indicated diagnosis-specific differences, such as a higher proportion of CD164+ cells and their subsets in DDH-OA, while pOA contained a significantly higher proportion of CD10+ and GD2+ cells and subsets, with CD271+ being marginally higher. Location-specific differences showed that CD271+ cells were more abundant in the Fh compared to the Ac in DDH-OA patients. Furthermore, immunohistochemical characterization of stromal bone-adjacent cells expressing MSPC markers (CD10, CD164, CD271, GD2) in the Ac and Fh compartments was performed. This research proved that immunophenotype profiles and morphological changes are both location- and disease-specific. Furthermore, it provided potentially effective targets for therapeutic strategies. Future research should analyze the differentiation potential of subsets identified in this study. After proper characterization, they can be selectively targeted, thus enhancing personalized medicine approaches in joint disease management.

[Translated article] Total hip arthroplasty with shelf acetabuloplasty in dysplastic coxarthrosis, mean follow-up of 7 years

INTRODUCTION

Developmental dysplasia of the hip is the cause of approximately one third of secondary coxarthrosis. Anatomy alterations make it difficult to place a total hip prosthesis in its anatomical position and for it to be stable in the long term; there are several techniques to achieve this goal. In the present work, we used autograft of the femoral head (shelf graft or reinforced roof), to improve the coverage of the acetabular component with favourable results.

MATERIALS AND METHODS

Sixteen cases were included in 14 patients with a diagnosis of developmental dysplasia of the hip (13 women and one man), the mean age was 44.3 years (range 35-68 years), with a mean follow-up of 7 years (range 1-15 years). All the cases were evaluated clinically and radiographically, to demonstrate the osseointegration of the graft and the functional results in the medium term.

RESULTS

All the acetabular components were placed in anatomical position (Ranawat technique), the mean percentage of host bone coverage was 54.53% (range 43.28-79.05%), obtaining additional coverage with the bone graft of 45.13%. Osseointegration of the graft of 100% at 12 weeks, resorption of the graft from the sixth month, stabilising in the third postoperative year. Only one case of dislocation is reported, no cases of infection, loosening, heterotopic ossification or revision.

CONCLUSION

This procedure has shown good functional results in the medium term with 100% osseointegration, despite cases of severe bone resorption of the graft that does not compromise the stability of the prosthesis.

Total hip arthroplasty with shelf acetabuloplasty in dysplastic coxarthrosis, mean follow-up of 7 years

Developmental dysplasia of the hip is the cause of approximately one third of secondary coxarthrosis. Anatomy alterations make it difficult to place a total hip prosthesis in its anatomical position and for it to be stable in the long term; there are several techniques to achieve this goal. In the present work, we used autograft of the femoral head (shelf graft or reinforced roof), to improve the coverage of the acetabular component with favorable results.

MATERIALS AD METHODS

Sixteen cases were included in 14 patients with a diagnosis of developmental dysplasia of the hip (13 women and one man), the mean age was 44.3 years (range 35-68 years), with a mean follow-up of 7 years (range 1-15 years). All the cases were evaluated clinically and radiographically, to demonstrate the osseointegration of the graft and the functional results in the medium term.

RESULTS

All the acetabular components were placed in anatomical position (Ranawat technique), the mean percentage of host bone coverage was 54.53% (range 43.28-79.05%), obtaining additional coverage with the bone graft of 45.13%. Osseointegration of the graft of 100% at 12 weeks, resorption of the graft from the sixth month, stabilizing in the third postoperative year. Only one case of dislocation is reported, no cases of infection, loosening, heterotopic ossification or revision.

CONCLUSION

This procedure has shown good functional results in the medium term with 100% osseointegration, despite cases of severe bone resorption of the graft that does not compromise the stability of the prosthesis.

Modified triple pelvic osteotomy for residual acetabular dysplasia through double incisions: Technical note and review of short-term results

PURPOSE

To assess validity, safety, and efficacy of the modified triple pelvic osteotomy (TPO) approach for correction of residual acetabular dysplasia.

METHODS

This is a retrospective case series conducted on 15 hips in 15 patients from 2019 to 2023 with residual acetabular dysplasia treated by modified TPO as described by Tonnis with two modifications. The first modification is using a single medial incision for pubic and ischial cuts (the Vladimirov modification). The second modification is having the ischial cut closer to the acetabulum (Li modification) allowing free movement of the acetabular fragment for better femoral head coverage. The mean age at the time of surgery was 11.85 years, (range 8-23). Cases presenting were 10 males (66.7%) and 5 females (33.3%). The mean follow-up period was 36.533 months (24-60 months).

RESULTS

Our study revealed significant clinical and radiological improvement. The CE angle improved from a mean value of 10° (range 2-17) pre-operatively to 32.785° (range 18°-40°) post-operatively. The AI improved from a mean value of 32° pre-operatively to a mean value of 13.89° post-operatively. HHS increased from a preoperative mean value of 74.80° to a post-operative mean value of 90.67°. Also, there was a significant improvement in ROM (abduction and internal rotation). LLD improved from a mean value of 2.60 cm preoperatively to a mean value of 0.37 cm postoperatively. Delayed union was found in 3 cases. No cases of osteonecrosis or neurovascular complication were encountered in our study.

CONCLUSION

The modified TPO technique using dual incisions can be considered safe and effective, providing adequate coverage of the femoral head in acetabular dysplasia with less surgical time, satisfactory functional outcomes, and minimal complications.

LEVEL OF EVIDENCE

IV.

The Three-Dimensional Criteria of Developmental Dysplasia of the Hip Using the Functional Pelvic Plane Is More Useful Than That Using the Anterior Pelvic Plane

Background: This retrospective cross-sectional study investigated the cutoff values (COVs) for developmental dysplasia of the hip (DDH) using a three-dimensional (3D) pelvic model reconstructed using computed tomography (CT). We included 107 healthy Japanese participants and 73 patients who had undergone curved periacetabular osteotomy (CPO) for DDH between 2012 and 2017. Methods: The hip CT images were adjusted to the anterior pelvic plane (APP), functional pelvic plane (FPP), sagittal anterior center-edge angle (ACEA), and sagittal posterior center-edge angle (PCEA). The lateral center-edge angle (LCEA), acetabular roof obliquity (ARO), anterior acetabular sector angle (AASA), and posterior acetabular sector angle (PASA) were measured. Receiver operating characteristic (ROC) curves were used to calculate the COVs, and the association between the parameters was analyzed using multiple logistic regression. Results: The ARO (≥10.2°) and LCEA (≤22.2°) were independent influencing factors for the APP, whereas the AASA (≤53.1°) and LCEA (≤24.5°) were independent influencing factors for the FPP. Conclusions: The 3D criteria for the diagnosis of DDH in Japanese individuals can identify DDH with insufficient anterior coverage, which anteroposterior plain radiographs cannot visualize, and can help determine indications for acetabular osteotomy.

Use of the flat panel detector fluoroscope reduces radiation exposure during periacetabular osteotomy

The Periacetabular Osteotomy is a technically demanding procedure that requires precise intraoperative evaluation of pelvic anatomy. Fluoroscopic images pose a radiation risk to operating room staff, scrubbed personnel, and the patient. Most commonly, a Standard Fluoroscope with an Image Intensifier is used. Our institution recently implemented the novel Fluoroscope with a Flat Panel Detector. The purpose of this study was to compare radiation dosage and accuracy between the two fluoroscopes. A retrospective review of a consecutive series of patients who underwent Periacetabular Osteotomy for symptomatic hip dysplasia was completed. The total radiation exposure dose (mGy) was recorded and compared for each case from the standard fluoroscope (n = 27) and the flat panel detector (n = 26) cohorts. Lateral center edge angle was measured and compared intraoperatively and at the six-week postoperative visit. A total of 53 patients (96% female) with a mean age and BMI of 17.84 (± 6.84) years and 22.66 (± 4.49) kg/m2 (standard fluoroscope) and 18.23 (± 4.21) years and 21.99 (± 4.00) kg/m2 (flat panel detector) were included. The standard fluoroscope averaged total radiation exposure to be 410.61(± 193.02) mGy, while the flat panel detector averaged 91.12 (± 49.64) mGy (p < 0.0001). The average difference (bias) between intraoperative and 6-week postoperative lateral center edge angle measurement was 0.36° (limits of agreement: - 3.19 to 2.47°) for the standard fluoroscope and 0.27° (limits of agreement: - 2.05 to 2.59°) for the flat panel detector cohort. Use of fluoroscopy with flat panel detector technology decreased the total radiation dose exposure intraoperatively and produced an equivalent assessment of intraoperative lateral center edge angle. Decreasing radiation exposure to young patients is imperative to reduce the risk of future comorbidities.

A New Arthroscopic Classification for Chondrolabral Disease in Patients Undergoing Surgery for Developmental Dysplasia of the Hip

BACKGROUND

Current classification systems for intra-articular pathology intraoperatively have been described for patients with femoroacetabular impingement rather than dysplasia.

PURPOSE

To (1) describe intra-articular findings in dysplastic hips undergoing combined hip arthroscopy and periacetabular osteotomy (PAO); (2) propose a new chondrolabral classification system for dysplastic hips based on these findings; and (3) correlate patient-reported outcome measures (PROM) with the newly proposed classification.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

A total of 46 hips underwent combined hip arthroscopy and PAO at our institution between September 2013 and December 2014, irrespective of symptoms or radiographic findings. PROMs were evaluated preoperatively and at 2 years postoperatively. At the time of hip arthroscopy, the chondrolabral junction was classified as normal without tear (1 hip, type 1); hypertrophic labrum without chondrolabral disruption (19 hips, type 2); chondrolabral disruption on the articular side, not extending into the capsular side (16 hips, type 3A); chondrolabral disruption extending through the capsular side (3 hips, type 3B); and exposed acetabular subchondral bone (7 hips, type 4).

RESULTS

There was a significant difference in postoperative modified Harris Hip Score (mHHS) (P = .020), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain scores (P = .037), and WOMAC total scores (P = .049) between chondrolabral junction types. Post hoc analyses demonstrated significant differences between type 2 (84.9 ± 12.9) and type 3A (67.8 ± 20.7; P = .198), and between type 2 and type 4 (59.3 ± 24.3; P = .011) in postoperative mHHS scores; and between type 2 (83.9 ± 12.9) and type 3A (68.9 ± 23.7; P = .045) in postoperative WOMAC total scores. In multivariate analysis, chondrolabral type 3 or type 4, age >35 years, and previous surgery were significantly correlated with worse mHHS scores at 2 years.

CONCLUSION

This new chondrolabral classification is proposed to describe intra-articular pathology seen during combined hip arthroscopy and PAO, specifically in dysplastic hips. More advanced chondrolabral disease was associated with worse PROMs at 2 years.

Perceived outcomes of periacetabular osteotomy

Aims

Social media is a popular resource for patients seeking medical information and sharing experiences. periacetabular osteotomy (PAO) is the gold-standard treatment for symptomatic acetabular dysplasia with good long-term outcomes. However, little is known regarding the perceived outcomes of PAO on social media. The aims of this study were to describe the perceived outcomes following PAO using three social media platforms: Facebook, Instagram, and X (formerly known as Twitter).

Methods

Facebook, Instagram, and X posts were retrospectively collected from 1 February 2023. Facebook posts were collected from the two most populated interest groups: "periacetabular osteotomy" and "PAO Australia." Instagram and X posts were queried using the most popular hashtags: #PAOwarrior, #periacetabularosteotomy, #periacetabularosteotomyrecovery, #PAOsurgery, and #PAOrecovery. Posts were assessed for demographic data (sex, race, location), perspective (patient, physician, professional organization, industry), timing (preoperative vs postoperative), and perceived outcome (positive, negative, neutral).

Results

A total of 1,054 Facebook posts, 1,003 Instagram posts, and 502 X posts were consecutively assessed from 887 unique authors. The majority (63.3%) of these posts were from patients in the postoperative period, with a median of 84 days postoperatively (interquartile range 20 to 275). The longest follow-up timeframe postoperatively was 20 years. Regarding perceived outcomes, 52.8% expressed satisfaction, 39.7% held neutral opinions, and 7.5% were dissatisfied. Most dissatisfied patients (50.9%) reported pain (chronic or uncontrolled acute) as an attributing factor.

Conclusion

Most PAO-perceived surgical outcomes on social media had a positive tone. Findings also indicate that a small percentage of patients reported negative perceived outcomes. However, dissatisfaction with PAO primarily stemmed from postoperative pain. Social media posts from other sources (physicians, hospitals, professional organizations, etc.) trend towards neutrality. Healthcare providers must consider the social media narratives of patients following PAO, as they may reveal additional outcome expectations and help improve patient-centred care, create informed decision-making, and optimize treatment outcomes.

Pelvic tilt affects superolateral coverage, but not superomedial coverage of the femoral head following periacetabular osteotomy

BACKGROUND

Pelvic tilt is an important sagittal parameter that varies greatly among individuals. The objective of this study was to quantify the effect of pelvic tilt on femoral head coverage and range of motion in a dysplastic population following periacetabular osteotomy.

METHODS

Twenty-three dysplastic hips from 19 patients (17 female, 2 male) were included in this study. Three-dimensional models were reconstructed using pre-operative CT images, and patient-specific neutral pelvic tilt was obtained on an anteroposterior X-ray. Following a simulated periacetabular osteotomy, the pelvic tilt was changed from -15° to +15°, and the effects on femoral head coverage and hip range of motion was quantified using a customized MATLAB program.

FINDINGS

Pelvic tilt did not significantly affect total femoral head coverage (P > 0.2). However, a 15° anterior tilt from neutral resulted in a 17.72 ± 9.45% increase in anterolateral coverage and a 23.96 ± 7.48% decrease in posterolateral coverage (P < 0.0001), as well as an 18.2 ± 8.4° loss of internal rotation at 90° of hip flexion. Contrarily, posterior pelvic tilt led to a 26.79 ± 9.04% reduction in anterolateral coverage (P < 0.0001) and an 18.02 ± 9.57% increase in posterolateral coverage (P < 0.0001), and the maximum internal rotation increased 11.8 ± 3.7°.

INTERPRETATION

While pelvic tilt did not affect total femoral head coverage, it had a significant impact on the distribution of coverage within the superolateral region of the femoral head. Anterior pelvic tilt led to increased anterolateral coverage, but also had a negative impact on hip range of motion. An optimal surgical plan should achieve adequate coverage while not significantly limiting the patient's mobility.

Pain, function and quality of life are impaired in adults undergoing periacetabular osteotomy (PAO) for hip dysplasia: a systematic review and meta-analysis

BACKGROUND

Hip dysplasia is a common condition in active adults with hip pain that can lead to joint degeneration. Periacetabular osteotomy (PAO) is a common surgical treatment for hip dysplasia. The effect of this surgery on pain, function and quality of life (QOL) has not been systematically analysed.

PURPOSE

In adults with hip dysplasia: (1) evaluate differences in pain, function and QOL in those undergoing PAO and healthy controls; (2) evaluate pre- to post-PAO changes in pain, function and QOL; (3) evaluate differences in pain, function and QOL in those with mild versus severe dysplasia, undergoing PAO; and (4) evaluate differences in pain, function and QOL in those having primary PAO versus those with previous hip arthroscopy.

METHODS

A comprehensive, reproducible search strategy was performed on 5 different databases. We included studies that assessed pain, function and QOL in adults undergoing PAO for hip dysplasia, using hip-specific patient reported outcomes measures.

RESULTS

From 5017 titles and abstracts screened, 62 studies were included. Meta-analysis showed PAO patients had worse outcomes pre- and post-PAO compared to healthy participants. Specifically, pain (standardised mean difference [SMD] 95% confidence interval [CI]): -4.05; -4.78 to -3.32), function (-2.81; -3.89 to -1.74), and QOL (-4.10; -4.43 to -3.77) were significantly poorer preoperatively.Meta-analysis found patients experienced improvements following PAO. Pain improved from pre-surgery to 1-year (standardised paired difference [SPD] 1.35; 95% CI, 1.02-1.67) and 2 years postoperatively (1.35; 1.16-1.54). For function, the activities of daily living scores at 1 year (1.22; 1.09-1.35) and 2 years (1.06; 0.9-1.22) and QOL at 1 year (1.36; 1.22-1.5) and 2 years (1.3; 1.1-1.5) all improved. No difference was found between patients undergoing PAO with mild versus severe dysplasia.

CONCLUSIONS

Before undergoing PAO surgery, adults with hip dysplasia have worse levels of pain, function and QOL compared to healthy participants. These levels improve following PAO, but do not reach the same level as their healthy participants.

REGISTRATION

PROSPERO (CRD42020144748).

The use of dual mobility acetabular cups in total hip replacement reduces dislocation rates in hip dysplasia patients

Total hip replacement arthroplasty (THA) in hip dysplasia patients has a higher dislocation rate than in patients with simple hip osteoarthritis due to anatomical deformation. Therefore, to reduce postoperative THA dislocation is the challenge for arthroplasty surgeons. From 2015 to 2020, 1525 patients underwent THA performed by two surgeons at a single institution. A total of 152 patients involving 172 THAs were included. The patients were classified into dual-mobility (DM) and fixed-bearing (FB) acetabular cup groups. The occurrence of postoperative dislocation and functional evaluation of the hip joint, was analyzed before and after surgery using the modified Harris hip score(mHHS). There was no difference in the preoperative demographics and radiographic parameters between the groups. The incidence of postoperative hip dislocation was significantly lower in the DM group (DM 0% vs. FB 9.0%) (P value = 0.003). The mHHS showed no difference before surgery and after surgery (DM 91.80 vs FB 92.03). Treating hip dysplasia patients with THA using a dual-mobility acetabular cup can reduce postoperative dislocations, and could be used for the better management of these patients.

Non-Operative Rehabilitation Principles for Use in Individuals with Acetabular Dysplasia: A North American Based Delphi Study

Background

Acetabular dysplasia (AD) is defined as a structurally deficient acetabulum and is a well-recognized cause of hip pain in young adults. While treatment of severe AD with a periacetabular osteotomy has demonstrated good long-term outcomes, a trial of non-operative management is often recommended in this population. This may be especially true in patients with milder deformities. Currently, there is a paucity of research pertaining to non-operative management of individuals with AD.

Purpose

To present expert-driven non-operative rehabilitation guidelines for use in individuals with AD.

Study Design

Delphi study.

Methods

A panel of 15 physiotherapists from North America who were identified as experts in non-operative rehabilitation of individuals with AD by a high-volume hip preservation surgeon participated in this Delphi study. Panelists were presented with 16 questions regarding evaluation and treatment principles of individuals with AD. A three-step Delphi method was utilized to establish consensus on non-operative rehabilitation principles for individuals presenting with AD.

Results

Total (100%) participation was achieved for all three survey rounds. Consensus, defined a piori as > 75%, was reached for 16/16 questions regarding evaluation principles, activity modifications, appropriate therapeutic exercise progression, return to activity/sport criteria, and indications for physician referral.

Conclusion

This North American based Delphi study presents expert-based consensus on non-operative rehabilitation principles for use in individuals with AD. Establishing guidelines for non-operative management in this population will help reduce practice variation and is the first step in stratifying individuals who would benefit from non-operative management. Future research should focus on patient-reported outcomes and rate of subsequent surgical intervention to determine the success of the guidelines reported in this study.

Level of Evidence

Level V.

Are Abnormal Muscle Biomechanics and Patient-reported Outcomes Associated in Patients With Hip Dysplasia?

BACKGROUND

Developmental dysplasia of the hip (DDH) is a major risk factor for the early development of hip osteoarthritis. Recent studies have demonstrated how DDH alters hip muscle moment arms and elevates muscle-induced biomechanical variables such as joint reaction forces and acetabular edge loads. Understanding the link between abnormal biomechanics and patient-reported outcome measures (PROMs) is important for evidence-based clinical interventions that improve patient symptoms and functional outcomes. To our knowledge, there are no reports of the relationships between muscle-induced biomechanics and PROMs.

QUESTIONS/PURPOSES

(1) Are there associations between PROMs and muscle-induced hip biomechanics during gait for patients with DDH and controls? (2) Are there associations among PROMs and separately among biomechanical variables?

METHODS

Participants in this prospective cross-sectional comparative study included 20 female patients with DDH who had no prior surgery or osteoarthritis and 15 female individuals with no evidence of hip pathology (controls) (age: median 23 years [range 16 to 39 years]; BMI: median 22 kg/m 2 [range 17 to 27 kg/m 2 ]). Muscle-induced biomechanical variables for this cohort were reported and had been calculated from patient-specific musculoskeletal models, motion data, and MRI. Biomechanical variables included joint reaction forces, acetabular edge loads, hip center lateralization, and gluteus medius muscle moment arm lengths. PROMs included the Hip Disability and Osteoarthritis Outcome Score (HOOS), the WOMAC, International Hip Outcome Tool-12, National Institutes of Health Patient-Reported Outcome Measure Information System (PROMIS) Pain Interference and Physical Function subscales, and University of California Los Angeles activity scale. Associations between PROMs and biomechanical variables were tested using Spearman rank-order correlations and corrected for multiple comparisons using the Benjamini-Yekutieli method. For this study, associations between variables were considered to exist when correlations were statistically significant (p < 0.05) and were either strong (ρ ≥ 0.60) or moderate (ρ = 0.40 to 0.59).

RESULTS

Acetabular edge load impulses (the cumulative acetabular edge load across the gait cycle), medially directed joint reaction forces, and hip center lateralization most commonly demonstrated moderate or strong associations with PROMs. The strongest associations were a negative correlation between acetabular edge load impulse on the superior acetabulum and the HOOS function in daily living subscale (ρ = -0.63; p = 0.001), followed by a negative correlation between hip center lateralization and the HOOS pain subscale (ρ = -0.6; p = 0.003), and a positive correlation between hip center lateralization and the PROMIS pain subscale (ρ = 0.62; p = 0.002). The University of California Los Angeles activity scale was the only PROM that did not demonstrate associations with any biomechanical variable. All PROMs, aside from the University of California Los Angeles activity scale, were associated with one another. Although most of the biomechanical variables were associated with one another, these relationships were not as consistent as those among PROMs.

CONCLUSION

The associations with PROMs detected in the current study suggest that muscle-induced biomechanics may have wide-reaching effects not only on loads within the hip, but also on patients' perceptions of their health and function. As the treatment of DDH evolves, patient-specific joint preservation strategies may benefit from targeting the underlying causes of biomechanical outcomes associated with PROMs.

LEVEL OF EVIDENCE

Level III, prognostic 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.

Subchondral fatigue fracture of the femoral head in young military recruits: Potential risk factors

BACKGROUND

Subchondral fatigue fracture of the femoral head (SFFFH) mainly occurs in young military recruits and might be confused with osteonecrosis of the femoral head. However, less research focuses on the risk factor for SFFFH.

AIM

To evaluate the intrinsic risk factors for SFFFH in young military recruits.

METHODS

X-ray and magnetic resonance imaging data were used for analysis. Acetabular anteversion of the superior acetabulum, acetabular anteversion of the center of the acetabulum (AVcen), anterior acetabular sector angle (AASA), posterior acetabular sector angle, superior acetabular sector angle, neck-shaft angle (NSA), inferior iliac angle (IIA), and ischiopubic angle were calculated. Then, logistic regression, receiver operating characteristic curve analysis, and independent samples t-test were performed to identify the risk factors for SFFFH.

RESULTS

Based on the results of logistic regression, age [odds ratio (OR): 1.33; 95% confidence interval (95%CI): 1.12-1.65; P = 0.0031] and treatment timing (OR: 0.86; 95%CI: 0.75-0.96; P = 0.015) could be considered as the indicators for SFFFH. AVcen (P = 0.0334), AASA (P = 0.0002), NSA (P = 0.0007), and IIA (P = 0.0316) were considered to have statistical significance. Further, AVcen (OR: 1.41; 95%CI: 1.04-1.95) and AASA (OR: 1.44; 95%CI: 1.21-1.77), especially AASA (area under curve: 66.6%), should be paid much more attention due to the higher OR than other indicators.

CONCLUSION

We have for the first time unveiled that AASA and age could be key risk factors for SFFFH, which further verifies that deficient anterior coverage of the acetabulum might be the main cause of SFFFH.

Birmingham Royal Orthopaedic Hospital (BROH) Femoral Offset-An Ancillary Measure of Adult Dysplasia of the Hip

Introduction  Adult dysplasia of the hip (ADH) is a disorder of abnormal development of the hip joint resulting in a shallow acetabulum and uncovering of the femoral head. Several radiological measurements such as the Tönnis angle (acetabular index), lateral center edge angle of Wiberg, and cross-sectional imaging parameters exist to calculate hip dysplasia. Aims  The aim of this article was to describe a new ancillary linear measure of ADH on cross-sectional imaging, the Birmingham Royal Orthopaedic Hospital (BROH) Femoral offset. Patients and Methods  Anteroposterior radiographs of the pelvis and computed tomography imaging of 100 consecutive patients with suspected hip dysplasia were reviewed. Demographic details and clinical indications were recorded. Tönnis angle was utilized to measure hip slope on radiographs and the BROH femoral offset was calculated for each patient. Student's t -test and one-way analysis of variance (ANOVA) were performed. Intraclass correlation coefficient analysis was evaluated to assess the reliability between observers. Results  There was a total of 100 patients (128 hips) included in the study (60 with normal Tönnis angle, 53 had dysplasia, and 15 had decreased Tönnis angle). The average BROH femoral offset in the dysplastic cohort was increased in comparison to the normal cohort with a statistically significant p -Value of 0.0001. The p -value was 0.00031 on ANOVA. The BROH femoral offset calculation revealed good intra- and interobserver reliability of 0.9 and 0.9, respectively. Conclusion  The BROH femoral offset can be an additional index for measuring ADH that is easier to calculate, and reproducible with good intra- and inter-observer reliability on cross-sectional imaging.

Improved Identification of Adolescent Hip Dysplasia Using a Screening Method Based on Lateral Center Edge Angle Measurements

BACKGROUND

In addition to the clinical exam, several quantitative measurement tools are performed on pelvic radiographs in the assessment of adolescent hip dysplasia at most dedicated pediatric hip preservation clinics, with the most commonly used measurement called the lateral center edge angle (LCEA). However, most pediatric radiologists do not use these quantitative measuring tools and instead make the diagnosis of adolescent hip dysplasia based on subjective review.

OBJECTIVE

The purpose of this study is to determine the additive value of a measurement-based diagnosis of adolescent hip dysplasia using LCEA versus subjective radiographic interpretation by pediatric radiologists.

METHODS

A review of pelvic radiographs for the binomial diagnosis of hip dysplasia was performed by four pediatric radiologists (two general, two musculoskeletal). The review included 97 pelvic AP radiographs (mean age 14.4 years [range 10-20 years], 81% female) for a total of 194 hips (58 cases of adolescent hip dysplasia and 136 normal) all of whom were evaluated in a tertiary care pediatric subspecialty hip preservation clinic. Subjective radiographic interpretation of each hip for a binomial diagnosis of hip dysplasia was performed. 2 weeks later and without knowledge of the subjective radiographic interpretation results, the same review was performed with LCEA measurement and a diagnosis of hip dysplasia made when LCEA angles were under 18 degrees. A comparison of sensitivity/specificity between methods per reader was conducted. A comparison of accuracy between methods for all readers combined was performed.

RESULTS

For all four reviewers, the sensitivity of subjective versus LCEA measurement-based diagnosis of hip dysplasia was 54-67% (average 58%) versus 64-72% (average 67%), respectively, and specificity was 87-95% (average 90%) versus 89-94% (average 92%), respectively. All four readers demonstrated an intra-reader trend for improvement in the diagnosis of adolescent hip dysplasia after the addition of LCEA measurements but was only statistically significant in one of the four readers. The combined accuracy of all four readers for subjective and LCEA measurement-based interpretation was 81% and 85%, respectively with p = 0.006.

CONCLUSION

Compared with subjective interpretation, LCEA measurements demonstrate increased diagnostic accuracy amongst pediatric radiologists for the correct diagnosis of adolescent hip dysplasia.

Biomechanical analysis and clinical observation of 3D-printed acetabular prosthesis for the acetabular reconstruction of total hip arthroplasty in Crowe III hip dysplasia

Objective: This study aimed to evaluate the biomechanical effectiveness of 3D-printed integrated acetabular prosthesis (IAP) and modular acetabular prosthesis (MAP) in reconstructing the acetabulum for patients with Crowe III developmental dysplasia of the hip (DDH). The results of this study can provide a theoretical foundation for the treatment of Crowe III DDH in total hip arthroplasty (THA). Methods: Finite element (FE) analysis models were created to reconstruct Crowe III DDH acetabular defects using IAP and MAP. The contact stress and relative micromotion between the acetabular prosthesis and the host bone were analyzed by gradually loading in three increments (210 N, 2100 N, and 4200 N). In addition, five patients with Crowe III DDH who underwent IAP acetabular reconstruction were observed. Results: At the same load, the peak values of IAP contact stress and relative micromotion were lower than those of MAP acetabular reconstruction. Under jogging load, the MAP metal augment's peak stress exceeded porous tantalum yield strength, and the risk of prosthesis fracture was higher. The peak stress in the bone interface in contact with the MAP during walking and jogging was higher than that in the cancellous bone, while that of IAP was higher than that of the cancellous bone only under jogging load, so the risk of MAP cancellous bone failure was greater. Under jogging load, the relative micromotion of the MAP reconstruction acetabular implant was 45.2 μm, which was not conducive to bone growth, while under three different loads, the relative micromotion of the IAP acetabular implant was 1.5-11.2 μm, all <40 μm, which was beneficial to bone growth. Five patients with IAP acetabular reconstruction were followed up for 11.8 ± 3.4 months, and the Harris score of the last follow-up was 85.4 ± 5.5. The imaging results showed good stability of all prostheses with no adverse conditions observed. Conclusion: Compared with acetabular reconstruction with MAP, IAP has a lower risk of loosening and fracture, as well as a better long-term stability. The application of IAP is an ideal acetabular reconstruction method for Crowe III DDH.

Functional outcome and athletic level after arthroscopic repair followed by triple pelvic osteotomy in patients with labral tears resulting from acetabular dysplasia

BACKGROUND

Patients with acetabular dysplasia are at a higher risk of developing symptomatic labral tears. Isolated treatments that address these pathologies are well established. Combined treatment with hip reorientation osteotomy using Bernese periacetabular osteotomy in addition to arthroscopic labral repair show good results. Studies that report the outcome in patients who received both arthroscopic labral repair and a triple pelvic osteotomy (TPO) are lacking. The aim of this study is to investigate the short to midterm functional outcome and activity level in these patients.

METHODS

This case series retrospectively included 8 patients (2 male, 6 female) with acetabular dysplasia (lateral center-edge angle [LCEA] ≤ 25°) and a labral tear on magnetic resonance arthrography (MRA). All patients underwent arthroscopic labral repair followed by TPO after an average period of 3 months (range 2-6). Average age at the time of surgery was 25 years (range 15-37). Patients were followed up and the following main parameters were assessed: LCEA, modified Harris hip score (mHSS), Tegner score, UCLA score, patient satisfaction on a scale of 1-4.

RESULTS

The mean follow-up was 19 months (range 15-25). The mean LCEA increased from 18° to 37° (p < 0.0001). The mHSS improved from a mean of 79 to 94 on final follow-up (p = 0.00123). The Tegner and UCLA scores had a median of 4 and 5, respectively. The mean LCEA increased from 18° to 37° (p < 0.0001). The mean patient satisfaction was 3.6.

CONCLUSION

Patients with evidence of a labral tear resulting from acetabular dysplasia benefit from arthroscopic repair followed by a TPO. The literature still lacks evidence that labral repair and reorientation osteotomy produce superior outcome compared to osteotomy alone. Treatment should consider clinical presentation in addition to radiological findings with emphasis on MRA.

Progression of Osteoarthritis at Long-term Follow-up in Patients Treated for Symptomatic Femoroacetabular Impingement With Hip Arthroscopy Compared With Nonsurgically Treated Patients

BACKGROUND

Femoroacetabular impingement (FAI) is a common cause of hip pain, especially in young patients. When left untreated, it has been demonstrated to be a risk factor for the onset or progression of osteoarthritis (OA) and has been identified as one of the main contributors leading to the need for total hip arthroplasty (THA) at a young age. While the short-term therapeutic potential of hip arthroscopy is widely recognized, little is known regarding its potential mid- to long-term preventive effect on the progression of hip OA.

PURPOSE

To (1) report clinical outcomes of arthroscopically treated FAI syndrome with a minimum 5-year follow-up and compare the results to a cohort with FAI treated nonsurgically and (2) determine the influence of hip arthroscopy on the onset and progression of hip OA in patients diagnosed with FAI.

STUDY DESIGN

Cohort study; Level of evidence, 3.

METHODS

Patients who had hip pain and were diagnosed with FAI were included. Exclusion criteria were (1) previous or concomitant hip surgery, (2) <5 years of follow-up, and (3) insufficient radiographs. Patients treated with hip arthroscopy were compared with a cohort of patients with FAI who were treated nonsurgically. Kaplan-Meier estimates of failure (defined as conversion to THA) were performed. Bivariate analysis and Cox regression were used to identify factors associated with inferior clinical and radiographic outcomes.

RESULTS

A total of 957 patients (650 female, 307 male; 1114 hips) (mean age, 28.03 ± 8.9 years [range, 6.5-41.0 years]) with FAI were included. A total of 132 hips underwent hip arthroscopy and 982 hips were nonoperatively treated. The mean follow-up was 12.5 ± 4.7 years (range, 5.0-23.4 years). At the final follow-up, the rate of OA progression was 26.5% in the operative group and 35.2% in the nonoperative cohort (P < .01). Conversion to THA was performed in 6.8% of the surgical patients and 10.5% of the initially nonsurgical patients (P = .19). Additionally, there was no significant difference in the risk of failure between the operatively and nonoperatively treated patients. Male sex, increased age at initial diagnosis, presence of cam morphology, and increased initial Tönnis grade were risk factors for failure (male sex: hazard ratio [HR], 2.3; P < .01; per year of increased age: HR, 1.1; P < .01; presence of cam: HR, 3.5; P < .01; per Tönnis grade: HR, 4.0; P < .01).

CONCLUSION

At a mean follow-up of nearly 13 years, 7% of patients of the surgical group experienced progression to THA, compared with 11% of the nonoperative control group. While most of the operative group showed little to no OA at final follow-up, moderate OA (Tönnis grade 2) was present in 12% of the cohort compared with 22% of nonsurgical patients. Increased age at diagnosis, male sex, presence of a cam morphology, and presence of initial arthritic joint changes were found to be risk factors for failure. The results of this study demonstrated evidence for a preventive effect of hip arthroscopy on the development and progression of OA in young patients with FAI at mid- to long-term follow-up.

Bilateral hip dysplasia in a South African male: A case study from the 17-18th century

OBJECTIVE

To identify, critically analyse and describe severe bilateral skeletal pathology involving the ossa coxae of an individual from historic era Cape Town.

MATERIALS

A single individual from the University of Cape Town's Human Skeletal Repository was analysed under research approval (HREC# 035/2021).

METHODS

An osteobiography was constructed, radiocarbon dating and isotopic analyses were conducted. Pathological description and contextualised disability analyses followed, along with differential diagnosis. The pelvis and femora were visualised macroscopically and radiographically.

RESULTS

This individual was a non-European middle-aged adult male who lived in the 17-18th centuries CE. Morphological changes showed hypoplastic hips with collapsed femoral heads and neoacetabulae. A diagnosis of developmental dysplasia of the hips (DDH) was made. Then a contextualised disability analysis including consideration of the clinical and functional impacts of the condition were applied. No signs of maltreatment, physiological stress or persistent infections were present. His bones were well developed, illustrating mobility and use.

CONCLUSIONS

He developed DDH early in life and lived through adulthood, and his strong, healthy bones suggest resilience, some mobility and contribution to society through less physically demanding tasks.

SIGNIFICANCE

Value for palaepathological analyses to inform and understand disability and culturally significant health mediation to offer a more objective interpretation and improve understanding of past people. It expands our understanding of the presence of DDH globally and in Africa and provides insight into disease impact for individuals with bilateral expression.

SUGGESTIONS FOR FUTURE RESEARCH

Further contextual research is required.

LIMITATIONS

Poor scene recovery hindered in-depth care analysis and interpretation of the condition.

Developmental dysplasia of the hip is common in patients undergoing total hip arthroplasty under 50 years of age

INTRODUCTION

Developmental dysplasia of the hip (DDH) refers to congenital and/or developmental hip instability that can result in hip joint subluxation or dislocation. When detected neonatally, conservative treatment with hip bracing can restore normal hip anatomy. Missed detection of DDH in the neonatal period or late development of DDH often requires surgical intervention to correct the abnormal anatomy. Furthermore, despite surgical intervention, residual sequelae may persist leading to early osteoarthritis of the hip joint requiring joint replacement surgery.

AIM

This study investigates the prevalence of hip dysplasia in patients undergoing total hip arthroplasty (THA) under 50 years of age.

METHODS

The hip arthroplasty database at a national referral centre was investigated from January 2014 to December 2020. In patients under 50 years of age, those with an adequate pre-operative anteroposterior pelvic radiograph without previous hip arthroplasty were included, while those with inadequate radiographs were excluded. The following measurements were made on the contralateral non-operated hip: (1) lateral centre-edge angle (LCEA), (2) Tönnis angle, (3) acetabular version, (4) acetabular depth, (5) femoral head lateralisation, (6) femoral head extrusion index, and (7) acetabular depth-to-width ratio.

RESULTS

In total, 451 patients were included in this study. Twenty two percent of the patients had hip dysplasia, based on a LCEA of <25° and 42.6% of patients had hip dysplasia, based on a Tönnis angle of > 10°. The mean LCEA and Tönnis angle were 31.47 ± 9.64 and 9.82 ± 6.79°, respectively.

CONCLUSION

Hip dysplasia is common in patients undergoing THA under the age of 50 years with over 40% having dysplasia according to the Tönnis angle. Classification of primary and secondary osteoarthritis in the joint registries will benefit our knowledge on the prevalence of DDH in the adult population.

Acetabular Rim Disorders: Epidemiology, Etiology, Management, and Outcomes

» Anatomic disorders of the acetabular rim are a common, correctable source of hip pain in younger patients.» Some common conditions of involving abnormal acetabular rim morphology include developmental dysplasia of the hip, pincer-type femoroacetabular impingement, acetabular protrusion, and acetabular retroversion.» Treatment option for these conditions were historically limited to open osteotomy and osteoplasty procedures; however, there is increasing use of arthroscopic intervention for these patients.» Arthroscopic intervention has demonstrated short-term success in a variety of focal acetabular rim disorders; however, further research is needed to determine the long-term outcomes of these procedures and their utility in more global pathology.

Psychological Factors as Risk Contributors for Poor Hip Function after Periacetabular Osteotomy

Psychologic comorbidities have been identified as risk factors for poor outcomes in orthopedic procedures, but their influence on the outcome of hip-preserving periacetabular osteotomy (PAO) remains uncertain. This retrospective cohort study aimed to assess the impact of patients' psychological health on the outcome of PAO in patients with hip dysplasia (HD) and acetabular retroversion (AR). The study included 110 patients undergoing PAO for HD or AR between 2019 and 2021. Standardized questionnaires were administered to assess psychological factors, postoperative hip function, and activity level (mean follow-up: 25 months). Linear regression analyses were used to examine the associations between psychological factors and postoperative hip function and activity level. Both HD and AR patients showed improved postoperative hip function and activity levels. Linear regression analyses revealed that depression significantly impaired postoperative outcomes in both groups, whereas somatization negatively influenced the outcome in AR patients. General health perceptions significantly contributed to an improved postoperative outcome. These findings highlight the importance of concomitantly addressing psychologically relevant factors in order to improve patient outcomes after PAO procedures. Future prospective studies should continue to investigate the impact of various psychological factors and explore possibilities of incorporating psychological support into routine postoperative care for these patient cohorts.

Postoperative hip center position is associated with gait symmetry in range of axial rotation in dysplasia patients after THA

Background

This study aimed to explore whether pre- or postoperative hip structures or surgical changes significantly influence hip range of motion (ROM) symmetry in patients with hip dysplasia during gait after total hip arthroplasty (THA) and provide possible surgical suggestions.

Methods

Fourteen patients with unilateral hip dysplasia underwent computed tomography before and after surgery to create three-dimensional hip models. Pre- and postoperative acetabular and femoral orientations, hip rotation centers (HRC), and femoral lengths were measured. Bilateral hip ROM during level walking after THA was quantified using dual fluoroscopy. The ROM symmetry in flexion-extension, adduction-abduction, and axial rotation was calculated using the symmetry index (SI). The relationship between SI and the above anatomical parameters and demographic characteristics was tested using Pearson's correlation and linear regression.

Results

The average SI values for flexion-extension, adduction-abduction, and axial rotation during gait were -0.29, -0.30, and -0.10, respectively. Significant correlations were detected mainly in the postoperative HRC position. A distally placed HRC was associated with increased SI values for adduction-abduction (R = -0.47, p = 0.045), while a medially placed HRC was associated with decreased SI values for axial rotation (R = 0.63, p = 0.007). A regression analysis indicated that horizontal HRC positions significantly determined axial rotational symmetry (R² = 0.40, p = 0.015). Normal axial rotation SI values were achieved with HRC between 17 mm medially and 16 mm laterally.

Conclusions

Postoperative HRC position was significantly correlated with gait symmetry in the frontal and transverse planes in patients with unilateral hip dysplasia after THA. Surgical reconstruction of the HRC to between 17 mm medially and 16 mm laterally may contribute to gait symmetry.

Effects of different pelvic osteotomies on acetabular morphology in developmental dysplasia of hip in children

Developmental dysplasia of hip seriously affects the health of children, and pelvic osteotomy is an important part of surgical treatment. Improving the shape of the acetabulum, preventing or delaying the progression of osteoarthritis is the ultimate goal of pelvic osteotomies. Re-directional osteotomies, reshaping osteotomies and salvage osteotomies are the three most common types of pelvic osteotomy. The influence of different pelvic osteotomy on acetabular morphology is different, and the acetabular morphology after osteotomy is closely related to the prognosis of the patients. But there lacks comparison of acetabular morphology between different pelvic osteotomies, on the basis of retrospective analysis and measurable imaging indicators, this study predicted the acetabular shape after developmental dysplasia of the hip pelvic osteotomy in order to help clinicians make reasonable and correct decisions and improve the planning and performance of pelvic osteotomy.

Evaluation of lateral and anterior center-edge angles according to sex and anterior pelvic plane tilt angle: a three-dimensional quantitative analysis

BACKGROUND

This study aimed to quantitatively evaluate lateral center-edge angle (LCEA) and anterior center-edge angle (ACEA) according to sex and the anterior pelvic plane (APP) tilt angle and analyze the correlation between these measurements and acetabular coverage.

METHODS

Computed tomography scans of 71 adults (38 men and 33 women) with normal hip joints were obtained. LCEA, anterior ACEA, and acetabular coverage were measured with APP tilt every 5° from - 30° to + 30° and were compared between the sexes. The correlation between acetabular coverage and LCEA/ACEA was also analyzed.

RESULTS

(1) LCEA, ACEA, and acetabular coverage were statistically larger in men than in women at all APP tilt angles (with the exception of acetabular coverage ≥ 25°). (2) LCEA, ACEA, and acetabular coverage differed according to APP tilt angle. LCEA and acetabular coverage showed maximum values at 10°. ACEA showed a tendency to increase by an average of 3.6° for every 5° increase in the APP tilt angle. LCEA demonstrated strong and very strong associations across all APP tilting angles, whereas ACEA showed a moderate association at angles ≥ 15° in men and ≥ 30° in women.

CONCLUSIONS

The LCEA and ACEA are adequate measurement methods that reflect actual acetabular coverage unless the pelvis is tilted excessively anteriorly. While pelvic tilting does not need to be considered for LCEA within the physiologic range, it should always be taken into account for ACEA, as it increases by an average of 3.6° for every 5° increase in APP tilt angle.

LEVEL OF EVIDENCE

Level III: retrospective cohort study.

An Interpretable Machine Learning Model for Predicting 10-Year Total Hip Arthroplasty Risk

BACKGROUND

As the demand for total hip arthroplasty (THA) rises, a predictive model for THA risk may aid patients and clinicians in augmenting shared decision-making. We aimed to develop and validate a model predicting THA within 10 years in patients using demographic, clinical, and deep learning (DL)-automated radiographic measurements.

METHODS

Patients enrolled in the Osteoarthritis Initiative were included. DL algorithms measuring osteoarthritis- and dysplasia-relevant parameters on baseline pelvis radiographs were developed. Demographic, clinical, and radiographic measurement variables were then used to train generalized additive models to predict THA within 10 years from baseline. A total of 4,796 patients were included (9,592 hips; 58% female; 230 THAs (2.4%)). Model performance using 1) baseline demographic and clinical variables 2) radiographic variables, and 3) all variables were compared.

RESULTS

Using 110 demographic and clinical variables, the model had a baseline area under the receiver operating curve (AUROC) of 0.68 and area under the precision recall curve (AUPRC) of 0.08. Using 26 DL-automated hip measurements, the AUROC was 0.77 and AUPRC was 0.22. Combining all variables, the model improved to an AUROC of 0.81 and AUPRC of 0.28. Three of the top five predictive features in the combined model were radiographic variables including minimum joint space along with hip pain and analgesic use. Partial dependency plots revealed predictive discontinuities for radiographic measurements consistent with literature thresholds of osteoarthritis progression and hip dysplasia.

CONCLUSION

A machine learning model predicting 10-year THA performed more accurately with DL radiographic measurements. The model weighted predictive variables in concordance with clinical THA-pathology assessments.

[Definition of hip dysplasia in 2023 : Signs of macro and micro instability]

BACKGROUND

Hip dysplasia is a complex static-dynamic pathology leading to chronic joint instability and osteoarthritis. Because our understanding of the underlying pathomorphologies of hip dysplasia, both on the macro and micro levels, has evolved, an updated definition is needed.

QUESTION

What is the definition of hip dysplasia in 2023?

METHODS

By summarizing and reviewing relevant literature, we provide an up-to-date definition of hip dysplasia with a guide to appropriately making the diagnosis.

RESULTS

In addition to the pathognomonic parameters, supportive and descriptive indicators, as well as secondary changes are used to fully characterize instability inherent in hip dysplasia. The primary diagnostic tool is always the plain anteroposterior pelvis radiograph, which can be supplemented by additional investigations (MRI of the hip with intraarticular contrast agent; CT) if necessary.

CONCLUSION

The complexity, subtlety, and diversity of the pathomorphology of residual hip dysplasia requires careful, multilevel diagnosis and treatment planning in specialized centers.

Greater hip abductor size in prearthritic patients with developmental dysplasia of the hip versus femoroacetabular impingement

Developmental dysplasia of the hip (DDH) and femoroacetabular impingement (FAI) are common hip pathologies and important risk factors for osteoarthritis, yet the disease mechanisms differ. DDH involves deficient femoral head coverage and a shortened abductor moment arm, so this study hypothesized that the cross-sectional area (CSA) of the gluteus medius/minimus muscle complex and the stabilizing iliocapsularis muscle would be larger in DDH versus FAI, without increased fatty infiltration. A longitudinal cohort identified prearthritic patients with DDH or FAI who underwent imaging before surgery. Patients with DDH and FAI (Cam, Pincer, or Mixed) were 1:1 matched based on age, sex, and body mass index. Magnetic resonance imaging was used to measure the gluteus medius/minimus complex and iliocapsularis in two transverse planes. Amira software was used to quantify muscle and noncontractile tissue. Paired samples t-tests were performed to compare muscle size and composition (p < 0.05). There were no differences in the iliocapsularis muscle. Patients with DDH had significantly larger CSA of the gluteus medius/minimus complex at both transverse planes, and the noncontractile tissue proportion did not differ. The mean difference in overall muscle CSA at the anterior inferior iliac spine was 4.07 ± 7.4 cm² (p = 0.005), with an average difference of 12.1%, and at the femoral head this was 2.40 ± 4.37 cm² (p = 0.004), with an average difference of 20.2%. This study reports a larger CSA of the gluteus medius/minimus muscle complex in DDH compared to FAI, without a difference in noncontractile tissue, indicating increased healthy muscle in DDH.

Patient-Reported Outcomes and Factors Impacting Success of the Periacetabular Osteotomy

Hip dysplasia is a condition affecting both infants and adults, characterized by a shallow acetabulum that does not sufficiently cover the head of the femur. This leads to instability of the hip and elevated levels of mechanical stress around the acetabular rim. A popular procedure for the correction of hip dysplasia is the periacetabular osteotomy (PAO), in which fluoroscopically guided osteotomies around the pelvis are made to allow for repositioning of the acetabulum to fit properly on the femoral head. This systematic review aims to analyze patient factors that impact outcomes, as well as patient-reported outcomes such as the Harris Hip Score (HHS) and the Western Ontario and McMaster Universities Arthritis Index (WOMAC). The patients in this review did not undergo any prior intervention for acetabular hip dysplasia, allowing for an unbiased reporting of outcomes from all included studies. Of studies reporting HHS, the mean preoperative HHS was 68.92 and the mean postoperative HHS was 89.1. Of the study that reported mHHS, the mean preoperative mHHS was 70, and the mean postoperative mHHS was 91. Of the studies reporting WOMAC, the mean preoperative WOMAC was 66, and the mean postoperative WOMAC was 63. Key findings of this review are that of the seven included studies, six achieved a minimally important clinical difference (MCID) based on patient-reported outcomes, and factors impacting outcome are preoperative Tönnis osteoarthritis (OA) grade, pre and postoperative lateral-center edge angle (LCEA), preoperative hip joint congruency, postoperative Tönnis angle, and age. In patients with no prior intervention for hip dysplasia, the PAO is a successful procedure with significant improvement in postoperative patient-reported outcomes. Despite the reported success of the PAO, proper patient selection is vital to avoid early conversions to total hip arthroplasty (THA) and prolonged pain. However, further investigation is prompted regarding the long-term survivorship of the PAO in patients with no prior intervention for hip dysplasia.

John Charnley Award: A Quantitative Fluoroscopic Tool Improves Acetabular Fragment Positioning in Periacetabular Osteotomy

BACKGROUND

Radiographic assessment of acetabular fragment positioning during periacetabular osteotomy (PAO) has been linked to hip survivorship. Intraoperative plain radiographs are time and resource intensive, while fluoroscopy can introduce image distortion affecting measurement accuracy. Our purpose was to determine whether intraoperative fluoroscopy-based measurements with a distortion correcting fluoroscopic tool improved PAO measurement targets.

METHODS

We retrospectively reviewed 570 PAOs; 136 PAOs utilized a distortion correcting fluoroscopic tool, and 434 PAOs performed with routine fluoroscopy, prior to this technology. Lateral center-edge angle (LCEA), acetabular index (AI), posterior wall sign (PWS), and anterior center-edge angle (ACEA) were measured on preoperative standing radiographs, intraoperative fluoroscopic images, and postoperative standing radiographs. Defined target zones of correction were AI: 0-10^°, ACEA: 25-40^°, LCEA: 25-40^°, PWS: negative. Postoperative correction in zones and patient-reported outcomes were compared using chi-square tests and paired t-tests, respectively.

RESULTS

The average difference between postcorrection fluoroscopic measurements and 6-week postoperative radiographs was 0.21° for LCEA, 0.01° for ACEA, and -0.07° for AI (all P < .01). The PWS agreement was 92%. The percentages of hips meeting target goals overall improved with the new fluoroscopic tool: 74%-92% for LCEA (P < .01), 72%-85% for ACEA (P < .01), and 69 versus 74% for AI (P = .25), though there was no improvement in PWS (85 versus 85%, P = .92). All patient-reported outcomes except PROMIS Mental Health were significantly improved at most recent follow-up.

CONCLUSIONS

Our study demonstrated improved PAO measurements and target goals with the use of a distortion correcting quantitative fluoroscopic real-time measuring device. This value-additive tool gives reliable quantitative measurements of correction without interfering with surgical workflow.

Fifty percent of patients undergoing periacetabular osteotomy for hip dysplasia showed normal findings upon neonatal ultrasound screening : Symptomatic hip dysplasia in adulthood despite inconspicuous neonatal hip ultrasound

Developmental dysplasia of the hip (DDH) is characterized by the pathomorphology of inadequate acetabular coverage of the femoral head leading to increased loading of the articular surface and acetabular rim. If left untreated, this ultimately leads to osteoarthritis. Germany introduced a nationwide universal ultrasound screening program for all newborn infants in 1996. Subsequently, the incidence of undiagnosed hip dislocation was significantly reduced. In this consecutive series of patients who underwent periacetabular osteotomy for the treatment of symptomatic dysplasia of the hip between October 2014 and October 2022 data regarding the U3 screening examination were analyzed. The data included whether the examination was performed, whether the findings were positive or negative, whether the patients underwent any form of treatment in the case of a positive finding and whether a control X‑ray was performed. This study provides evidence that acetabular undercoverage cannot be ruled out based on a normal finding in ultrasonography screening. Furthermore, the study also shows that residual dysplasia may persist despite attempts of conservative treatment.

Is the Femoral-Epiphyseal Acetabular Roof (FEAR) index associated with hip pain in patients with hip dysplasia?

BACKGROUND

Micro instability of the hip joint has been suggested to cause pain in patients with hip dysplasia. Recently, the Femoral-Epiphyseal Acetabular Roof (FEAR) index has been developed to evaluate hip instability in patients with dysplasia.

PURPOSE

To investigate associations between the FEAR index and patient-reported outcomes before and six months after periacetabular osteotomy (PAO).

MATERIAL AND METHODS

Radiographs of patients with hip dysplasia who underwent PAO between 2018 and 2020 were retrospectively assessed by a radiologist and an orthopedic surgeon. Radiographic measurements indicative of hip instability (Shenton's line, FEAR index, center-edge angle of Wiberg, acetabular index of Tönnis, and the femoral neck-shaft angle) were measured. Data on hip pain, function, and quality of life were collected prospectively using the Hip dysfunction and Osteoarthritis Outcome Score (HOOS).

RESULTS

A total of 222 patients were included in the study. All radiographic measurements and patient-reported outcomes improved significantly from preoperative to six months postoperative (P < 0.001). There were no differences in the change score of patient-reported outcomes between patients with a FEAR index >2° (indicative of hip instability) and patients with a FEAR index ≤2°.

CONCLUSION

The FEAR index was not associated with hip pain, function, and quality of life among patients with hip dysplasia. This study did not find evidence supporting that instability defined by the FEAR index caused pain in patients with hip dysplasia.

Deep Learning for Fully Automated Radiographic Measurements of the Pelvis and Hip

The morphometry of the hip and pelvis can be evaluated in native radiographs. Artificial-intelligence-assisted analyses provide objective, accurate, and reproducible results. This study investigates the performance of an artificial intelligence (AI)-based software using deep learning algorithms to measure radiological parameters that identify femoroacetabular impingement and hip dysplasia. Sixty-two radiographs (124 hips) were manually evaluated by three observers and fully automated analyses were performed by an AI-driven software (HIPPO™, ImageBiopsy Lab, Vienna, Austria). We compared the performance of the three human readers with the HIPPO™ using a Bayesian mixed model. For this purpose, we used the absolute deviation from the median ratings of all readers and HIPPO™. Our results indicate a high probability that the AI-driven software ranks better than at least one manual reader for the majority of outcome measures. Hence, fully automated analyses could provide reproducible results and facilitate identifying radiographic signs of hip disorders.

Femoral head and neck autograft in arthroplasty for developmental dysplasia of the hip: a systematic review of long-term outcomes

PURPOSE

Total hip arthroplasty (THA) with an acetabular component and an autogenous femoral head graft for acetabular reconstruction in developmental dysplasia of the hip was first described by Harris et al. in 1977. While a number of studies have addressed the aforementioned scenario over the last decades, most lack sufficient numbers and follow-up. As such, we analyzed long-term outcomes of THAs with femoral autograft for arthrosis secondary to hip dysplasia.

METHODS

A systematic review was performed using a structured PubMed, Web of Science, Ovid MEDLINE, and Cochrane analysis, based on the PRISMA criteria. All original studies from 1977 to 2022 with a mean follow-up of 10 or more years were included. Methodological Index for Nonrandomized Studies (MINORS) were used for quality assessment.

RESULTS

A total of 26 studies with 1316 patients (87% females) undergoing 1543 THAs with femoral autograft (2 times neck graft, 24 times head graft) were included. Mean age was 52 years (range, 28-73) and the mean follow-up was 13 years (range, 9-18). The revision rate was 8.3% (n = 129), and 73% of revisions were for loosening. Rate of infection (0.5%) and dislocations (1%) were low. Radiographic analysis revealed 167 loose acetabular components (11%) and 118 cases of graft resorption (7.6%). Mean Harris Hip Score increased from 42 to 85. Mean MINORS score was 11, and no study was level of evidence I or II.

CONCLUSIONS

Femoral autograft with THA may be a viable long-term option for hip reconstruction in developmental dysplasia of the hip. However, moderate loosening rates and low level of evidence must be acknowledged before drawing the final conclusions.

LEVEL OF EVIDENCE

Therapeutic Level III.

The economics of patients undergoing periacetabular osteotomy for hip dysplasia: the financial relationship between physicians and hospitals

Periacetabular osteotomy (PAO) is the gold standard for treating hip dysplasia in patients with preserved articular cartilage. The aim of this study is to evaluate the financial relationship between facility and professional revenue for patients undergoing PAO for hip dysplasia and acetabular version abnormalities. All patients who underwent PAO for hip dysplasia by a single surgeon at a tertiary academic medical center between December 2016 and November 2020 were identified. Financial records for facility and professional services were reviewed and analyzed. The orthopedic charge multiplier, the dollars of facility charge created by a single dollar of orthopedic professional charge, and orthopedic net revenue multiplier, the dollars collected by the hospital for facility services generated for each dollar collected by the orthopedic surgeon, were calculated. A total of 36 patients were included in the study. The mean total charge for all patients was $144 939.35 ± $23 726.48 (range $109 002.71 to $227 290.20), and the average total revenue for all patients was $44 218.79 ± $12 352.97 (range $29 397.39 to $90,830.62). The mean orthopedic charge multiplier was 2.47 ± 1.32 (range 0.78-6.53), and the net revenue collection multiplier was 8.62 ± 10.69 (range, 1.20-57.80). The majority of charges and revenue related to care of patients undergoing PAO return to the hospital. The significant mean orthopedic charge multiplier for this procedure increases the value of the service and the surgeon to hospital profitability. This information can help shape the relationship between the hospital and the surgeon and create a firm platform to advocate for program advancement.

Artificial intelligence-generated hip radiological measurements are fast and adequate for reliable assessment of hip dysplasia

Aims

Hip dysplasia (HD) leads to premature osteoarthritis. Timely detection and correction of HD has been shown to improve pain, functional status, and hip longevity. Several time-consuming radiological measurements are currently used to confirm HD. An artificial intelligence (AI) software named HIPPO automatically locates anatomical landmarks on anteroposterior pelvis radiographs and performs the needed measurements. The primary aim of this study was to assess the reliability of this tool as compared to multi-reader evaluation in clinically proven cases of adult HD. The secondary aims were to assess the time savings achieved and evaluate inter-reader assessment.

Methods

A consecutive preoperative sample of 130 HD patients (256 hips) was used. This cohort included 82.3% females (n = 107) and 17.7% males (n = 23) with median patient age of 28.6 years (interquartile range (IQR) 22.5 to 37.2). Three trained readers’ measurements were compared to AI outputs of lateral centre-edge angle (LCEA), caput-collum-diaphyseal (CCD) angle, pelvic obliquity, Tönnis angle, Sharp’s angle, and femoral head coverage. Intraclass correlation coefficients (ICC) and Bland-Altman analyses were obtained.

Results

Among 256 hips with AI outputs, all six hip AI measurements were successfully obtained. The AI-reader correlations were generally good (ICC 0.60 to 0.74) to excellent (ICC > 0.75). There was lower agreement for CCD angle measurement. Most widely used measurements for HD diagnosis (LCEA and Tönnis angle) demonstrated good to excellent inter-method reliability (ICC 0.71 to 0.86 and 0.82 to 0.90, respectively). The median reading time for the three readers and AI was 212 (IQR 197 to 230), 131 (IQR 126 to 147), 734 (IQR 690 to 786), and 41 (IQR 38 to 44) seconds, respectively.

Conclusion

This study showed that AI-based software demonstrated reliable radiological assessment of patients with HD with significant interpretation-related time savings. Cite this article: Bone Jt Open 2022;3(11):877–884.

Appropriate Surgical Timing of Salter Innominate Osteotomy for Residual Acetabular Dysplasia in Children

BACKGROUND

Salter innominate osteotomy (SIO) provides favorable results for treating residual acetabular dysplasia in young children. In this study, we examined the midterm results of SIO according to the age at surgery to determine the optimal timing of this procedure.

METHODS

We retrospectively examined 50 hips of 42 patients (8 boys and 34 girls) with acetabular dysplasia who underwent SIO and were followed up until skeletal maturity. The center-edge angle (CEA) was measured based on the anteroposterior radiographs of the hip obtained before surgery, 5 weeks after surgery, and at the latest follow-up. Severin classification was evaluated at the latest follow-up. Patients were categorized into 3 groups according to age at surgery: younger than 7 years of age (group A), 7 to 8 years of age (group B), and 9 years of age or older (group C).

RESULTS

The mean preoperative CEA level of 0.9 degrees improved to 17.1 degrees postoperatively, which was increased to 28.1 degrees at the latest examination. Overall, 45 hips (90%) were classified as Severin I or II, with 96% in group A, 94% in group B, and 57% in group C. In group C, postoperative acetabular coverage was similar to that in the other groups (16.6 degrees in group A, 14.8 degrees in group B, and 18.1 degrees in group C), although the final outcome was unsatisfactory. The average improvement in CEA from postoperative to skeletal maturity was significantly smaller in group C than in the other groups (12.7 degrees in group A, 11.3 degrees in group B, and 3.0 degrees in group C).

CONCLUSIONS

SIO showed favorable outcomes with satisfactory acetabular coverage at skeletal maturity. However, satisfactory acetabular coverage could not be obtained in some older patients because of limited postoperative remodeling capacity and smaller secondary improvement of CEA. We recommend that SIO should be performed in patients aged 8 years or younger.

LEVEL OF EVIDENCE

Level III-retrospective comparative study.

Comparing the effect of cup placement between true and false acetabula in total hip arthroplasty in patients with Crowe type 3 dysplastic hip: A randomized clinical trial

BACKGROUND

Hip dysplasia is one of the most widespread hip disorders. Total hip arthroplasty (THA) is the preferred treatment in patients with cup placement choices in true or false acetabulum. The objective of this research was to compare the effectiveness of the two mentioned procedures.

MATERIALS AND METHODS

This study was a randomized, open-label, parallel-group clinical trial, in which 46 patients/51 hips with Crowe type 3 dysplastic hip having THA were assigned to two groups: Group 1 - patients who had cup placement in the true acetabulum and Group 2 - patients who underwent cup placement in the false acetabulum. The variables that were evaluated and analyzed included severity of pain using the visual analog scale (VAS), range of motion (ROM), gait ability, the need for repeated joint replacement, and the Harris Hip Score (HHS).

RESULTS

Forty-six patients/51 hips were included in the present study. The patients who were evaluated included 30 (65.2%) males and 16 (34.8%) females. The mean age in the population under study was 71.0 ± 10.22, and the mean body mass index of participants was 26.34 ± 2.22 kg/m². The basic parameters in the two research groups were similar (P > 0.05). There were no significant differences between the two groups in terms of the mean values of VAS and ROM (P > 0.05); however, the mean HHS was significantly higher in the true acetabulum group, 57.90 ± 18.47 versus 48.29 ± 13.80 (P = 0.04).

CONCLUSION

The effectiveness of cup placements both in the true and false acetabula was similar in all of the evaluated variables in terms of clinical outcomes except for HHS which was higher in the true acetabulum group. To further support the results of this research, it is recommended that more research be done on a greater population.

Treatment of Severe Hip Dysplasia with Leg Length Discrepancy Using Spherical Periacetabular Osteotomy

Case. A 20-year-old woman with severe subluxation of the hip displayed a leg length discrepancy of approximately 20 mm. The proposed treatment was a spherical periacetabular osteotomy (SPO) for joint preservation and postoperative leg length maintenance. SPO is a novel periacetabular osteotomy procedure. At her 3-year follow-up, the patient had functional, pain-free motion and high satisfaction. In this case, the SPO technique was able to achieve satisfactory clinical results without further exacerbating the leg length discrepancy after surgery.