Center-edge Angle Research Articles

Early And Mid-Term Radiological Results of Isolated Pembersal Procedure in Cases of Developmental Dislocation of The Hip

Aim: Early diagnosis and timely care is important in patients with Developmental Hip Dysplasia (DDH). Late presenting or neglected patients may require various osteotomy procedures. There is a limited number of articles in the literature on Pembersal osteotomy in DDH surgery. The aim of this study was to assess the outcomes of isolated Pembersal osteotomy in children over 18 months of age with DDH. Materials and Methods: A retrospective analysis was made of the outcomes of patients who underwent Pembersal osteotomy for DDH at our clinic from 2014 to 2021. The study included 9 children (7 girls, 2 boys) aged between 19 and 36 months with at least 2 years of follow-up who underwent isolated periacetabular Pembersal osteotomy with open reduction. Preoperative, early postoperative, 6 weeks postoperative and final follow-up radiographs were evaluated and Wiberg's centre-edge angle (CEA), the acetabular index (AI) and Tönnis grades were noted. Results: The mean age of the patients was 28.75 months and the follow-up period was 50.33 months. CEA and AI showed improvement in the early postoperative period and this improvement continued in the later periods. Tönnis staging showed postoperative improvement in all patients, and this improvement continued in the early postoperative period and on the 6-week follow-up radiographs. At the final follow-up examination, 3 hips had CEA <20º, AI >20º and Tönnis stage ≥2 and these 3 hips were considered as a radiologically poor outcome. Conclusion: This study demonstrated that isolated Pembersal osteotomy is an effective and safe option for the treatment of developmental dysplasia of the hip, with improvement in acetabular index and other radiological parameters. Keywords: Developmental dysplasia of the hip, periacetabular osteotomy, Pembersal osteotomy, centre-edge angle, acetabular index

Long-term Outcomes of Primary Hip Arthroscopy: Multicenter Analysis at Minimum 10-Year Follow-up With Attention to Labral and Capsular Management

Background: Hip arthroscopy is rapidly advancing, with positive published outcomes at short- and midterm follow-up; however, available long-term data remain limited. Purpose: To evaluate outcomes of primary hip arthroscopy at a minimum 10-year follow-up at 2 academic centers by describing patient-reported outcomes and determining reoperation and total hip arthroplasty (THA) rates. Study Design: Case series; Level of evidence, 4. Methods: Patients with primary hip arthroscopy performed between January 1988 and April 2013 at 2 academic centers were evaluated for postoperative patient-reported outcomes—including the visual analog scale, Tegner Activity Scale score, Hip Outcome Score Activities of Daily Living and Sport Specific subscales, modified Harris Hip Score, Nonarthritic Hip Score, 12-item International Hip Outcome Tool, surgery satisfaction, and reoperations. Results: A total of 294 patients undergoing primary hip arthroscopy (age, 40 ± 14 years; 66% women; body mass index, 27 ± 6) were followed for 12 ± 3 years (range, 10-24 years) postoperatively. Labral debridement and repair were performed in 41% and 59% of patients, respectively. Of all patients who underwent interportal capsulotomy, 2% were extended to a T-capsulotomy, and 11% underwent capsular repair. At final follow-up, patients reported a mean visual analog scale at rest of 2 ± 2 and with use of 3 ± 3, a 12-item International Hip Outcome Tool of 68 ± 27, a Nonarthritic Hip Score of 81 ± 18, a modified Harris Hip Score of 79 ± 17, and a Hip Outcome Score Activities of Daily Living of 82 ± 19 and Sport Specific subscale of 74 ± 25. The mean surgical satisfaction was 8.4 ± 2.4 on a 10-point scale, with 10 representing the highest level of satisfaction. In total, 96 hips (33%) underwent reoperation—including 65 hips (22%) converting to THA. THA risk factors included older age, higher body mass index, lower lateral center-edge angle, larger alpha angle, higher preoperative Tönnis grade, as well as labral debridement and capsular nonrepair (P≤ .039). Patients undergoing combined labral and capsular repair demonstrated a THA conversion rate of 3% compared with 31% for patients undergoing combined labral debridement and capsular nonrepair (P = .006). Labral repair trended toward increased 10-year THA-free survival (84% vs 77%; P = .085), while capsular repair demonstrated significantly increased 10-year THA-free survival (97% vs 79%; P = .033). Conclusion: At a minimum 10-year follow-up, patients undergoing primary hip arthroscopy demonstrated high satisfaction and acceptable outcome scores. In total, 33% of patients underwent reoperation—including 22% who underwent THA. Conversion to THA was associated with patient factors including older age, higher Tönnis grade, and potentially modifiable surgical factors such as labral debridement and capsular nonrepair.

Neonatal Ultrasound and Radiographic Markers of Hip Dysplasia in Young Adults.

To examine radiologic outcomes at skeletal maturity of sonographically normal, immature, mildly, and severely dysplastic newborn hips. During 1988 to 1990, 11 925 newborns were enrolled in a randomized controlled trial examining screening strategies for developmental hip dysplasia. In total, 4469 were invited to clinical and radiologic follow-up 18 years later, of which 1735 had received neonatal ultrasound. Radiographic markers for dysplasia in left adult hips included the center-edge (CE) angle. At follow-up, 984 of 1735 (56.7%) with newborn ultrasound met, of which 966 (614 females) had valid radiographs and were thus included. For females, 34 (10.2%) and 1 (0.3%) of the 332 sonographically normal left neonatal hips were judged borderline (20°≤ CE <25°) or dysplastic (CE <20°) at skeletal maturity respectively. Corresponding numbers were 36 (19.7%) and 3 (1.6%) of the 183 immature, 12 (15.6%) and 2 (2.6%) of the 77 mildly dysplastic, and 3 (13.6%) and 3 (13.6%) of the 22 severely dysplastic neonatal left hips (P ≤ .001). In males, no associations were found. In females, adult joint hypermobility was associated with sonographic neonatal hip instability (P = .046), as well as with adult acetabular dysplasia (P = .024). Significant associations between neonatal hip phenotypes and adult dysplasia were revealed in females. This indicates the possibility of different mechanisms affecting the course of developmental dysplasia of the hip for females and males, prompting consideration of prolonged clinical and radiologic follow-up for females with dysplastic neonatal hips. Results in males are limited by low numbers of dysplastic hips. The significance of joint hypermobility warrants further investigation.

Pincer Morphology Is Not Associated With Hip Osteoarthritis Unless Hip Pain Is Present: Follow-Up Data From a Prospective Cohort Study.

The objective of this study was to assess the relationship between pincer morphology and radiographic hip osteoarthritis (RHOA) over 2, 5, 8, and 10 years' follow-up and to study the interaction between pincer morphology and pain. Individuals from the prospective Cohort Hip and Cohort Knee study were drawn. Anteroposterior pelvic and false profile radiographs were obtained. Hips free of definite RHOA (Kellgren and Lawrence [KL] grade 0 or 1) at baseline were included. Pincer morphology was defined as a lateral or anterior center edge angle or both ≥40° at baseline. Incident RHOA was defined as KL ≥ 2 or total hip replacement at follow-up. Multivariable logistic regression with generalized estimating equations estimated the associations at follow-up. Associations were expressed as unadjusted odds ratios (ORs) and adjusted ORs with 95% confidence intervals (CIs). An interaction term was added to investigate whether pincer morphology had a different effect on symptomatic hips. Incident RHOA developed in 69 hips (5%) at2 years' follow-up, in 178 hips (14%) at 5 years' follow-up, in 279 hips (24%) at 8 years' follow-up, and in 495 hips (42%) at 10 years' follow-up. No significant associations were found between pincer morphology and incident RHOA (adjusted OR 0.35 [95% CI 0.06-2.15]; adjusted OR 1.50 [95% CI 0.94-2.38]). Significant interactions between pain and anterior pincer morphology in predicting incident RHOA were found at 5, 8, and 10 years' follow-up (OR 1.97 [95% CI 1.03-3.78]; OR 3.41 [95% CI 1.35-8.61]). No associations were found between radiographic pincer morphology and incident RHOA at any follow-up moment. Anteriorly located pincer morphology with hip pain, however, was significantly associated with incident RHOA. This highlights the importance of studying symptoms and hip morphology simultaneously.

Chiari Osteotomy in the Children: Mid-term Follow-Up Results.

Introduction The Chiari osteotomy enlarges the acetabulum to increase coverage of the femoral head. It is performed as a salvage procedure on a noncongruent, yet in-place, hip. This study aims to assess the clinical and radiographic outcomes of Chiari pelvic osteotomy for treating hip dysplasia in children. Methods This is acase series conducted in the pediatric orthopedic trauma department of the Centre Hospitalier Universitaire Hassan II, Fez, Morocco, over a 10-year period from January 2011 to December 2020. The study included patients who were being treated for hip dysplasia and had undergone a Chiari osteotomy. Two types of assessments were used to evaluate global hip function: a clinical assessment using the Merle d'Aubigné and Postel score, and a radiological assessment involving measurements taken from frontal pelvic radiographs. Results A total of 12 Chiari osteotomies were performed in nine patients. The mean age at surgery was 10.8 ± 1.7 years and the mean follow-up was 4.6 ± 2.78 years. The clinical assessment score improved statistically during the last follow-up compared with the preoperative measurements for pain (p<0.001), mobility (p = 0.002), walking (p<0.001), and total score (p< 0.001), for which 3.8 ± 1.9 points could be gained. Surgically, the osteotomy line height was 5.4 ± 2.6 mm, the osteotomy angle was 12.5 ± 2.2°, and the translated distance was 18.5 ± 3.2 mm.Regarding radiological evaluation, the comparison of angle measurements between preoperative and final recoil was statistically significant for both the vertical center edge (VCE) angle (p<0.001) with a mean gain of 16.33 ± 4.79° and the high transverse edge (HTE) angle (p = 0.002) with a mean loss of 12.67 ± 10.88°. Conclusion Chiari pelvic osteotomy is a complex procedure that requires very precise techniques. However, it results in remarkable relief for patients, providing an immediate impact on the Merle d'Aubigné and Postel score, particularly with regard to pain.

Prediction of 3-Dimensional Coverage Surface Area of the Femoral Head in Hip Dysplasia Through Conventional Computed Tomography.

Assessment of 3-dimensional (3D) femoral head coverage is critical in evaluating, preoperative planning, and treating hip dysplasia. To (1) propose a mathematical model to establish 3D femoral head coverage using conventional computed tomography (CT), (2) determine the correlation of 2D parameters with 3D coverage, and (3) characterize the patterns of dysplasia based on 3D morphology. Cross-sectional study; Level of evidence, 3. We identified 30 patients (n = hips) with symptomatic dysplasia and 30 patients (n = hips) without dysplasia. Patients with dysplastic hips were matched with regard to sex, age, and body mass index to those with nondysplastic hips. Preoperative CTs were analyzed using 3D software, and 3D femoral head surface area coverage (FHSAC; in %) was assessed in 4 quadrant zones: anteromedial, anterolateral, posteromedial, and posterolateral. To assess lateral coverage of the femoral head, we introduced the anterolateral femoral head coverage angle (ALFC) and the posterolateral femoral head coverage angle (PLFC). Reduced femoral head coverage was more pronounced in dysplastic versus nondysplastic hips in the anterolateral quadrant (18% vs 40.7%, respectively) and posterolateral quadrant (35.8% vs 56.9%, respectively) (P < .0001 for both). Dysplastic hips had smaller ALFC and PLFC (18.4° vs 38.7°; P < .0001; 47.2° vs 72.3°; P = .0002). Anterolateral and posterolateral FHSAC were strongly correlated with the ALFC (r = 0.88; P < .0001) and the PLFC (r = 0.82; P < .0001) along with the lateral center-edge angle (anterolateral, r = 0.75; P < .0001; posterolateral, r = 0.73; P < .0001). Prediction models established for FHSAC had strong agreement with explanatory CT variables (anterolateral: r = 0.91; P < .0001; posterolateral: r = 0.90; P < .0001). The cutoff values for anterolateral and posterolateral FHSAC were 25% and 41%, respectively. In dysplastic hips, global deficiency was most common (15/30 hips), 9 hips showed an anterolateral deficiency, and 4 hips had a posterolateral deficiency pattern. The ALFC and The PLFC were strongly correlated with 3D lateral FHSAC and were able to predict 3D coverage accurately.

Association of 5-Year Hip Arthroscopy Outcomes with Hip Morphology and Cartilage Status at Time of Surgery: A National Registry Study With HAGOS Outcomes in 281 Patients With Femoroacetabular Impingement Syndrome.

The effects of specific bony hip morphologies, cam and dysplasia, and cartilage damage on mid- and long-term (≥5 years) patient-reported outcomes (PROs) are understudied. To investigate if changes in PROs from preoperatively to 5 years after hip arthroscopy are associated with preoperative bony hip morphology and cartilage status in patients with femoroacetabular impingement syndrome. Cohort study; Level of evidence, 3. Patients were identified in the Danish Hip Arthroscopy Registry. Hip and groin function was assessed from preoperatively to 5 years postoperatively with the Copenhagen Hip and Groin Outcome Score (HAGOS) Activities of Daily Living (ADL) and Sports and Recreation (Sport) subscales. Morphology was defined using the anterior alpha angle (AA) and lateral center-edge angle (LCEA) as follows: mild to moderate cam (55°≤ AA < 78°), severe cam (AA ≥ 78°), pincer (LCEA > 39°), and borderline dysplasia (20°≤ LCEA < 25°). Joint space width (JSW) was defined as slightly reduced (3.1 mm ≤ JSW ≤ 4 mm) or severely reduced (2.1 mm ≤ JSW ≤ 3 mm). Acetabular cartilage status was defined by modified Beck grades 0 to 4 and femoral head cartilage status by International Cartilage Regeneration & Joint Preservation Society grades 0 to 4. Acetabular and femoral cartilage injury areas were categorized as <1, 1 to 2, or >2 cm2. Multiple regression analyses assessed adjusted associations between hip morphology and cartilage injuries with improvement in HAGOS-ADL and HAGOS-Sport. The study included 281 patients (age, 35 ± 10 years; 52.3% female). No cam and mild-to-moderate cam were associated with greater improvement in HAGOS-ADL (16 points [P = .002] and 7 points [P = .038], respectively) compared with severe cam. Normal JSW was associated with greater improvement in HAGOS-ADL (21 points; P = .026) compared with severely reduced JSW. Femoral head cartilage injury area <1 cm2 was associated with greater improvements in HAGOS-ADL (17 points; P = .03) and HAGOS-Sport (21 points; P = .035) compared with femoral cartilage injury area >2 cm2. Patients having no-to-moderate cam morphology, normal JSW, or femoral head cartilage injury area <1 cm2 had greater improvement in PROs 5 years after hip arthroscopy compared with patients having severe cam morphology, severely reduced JSW, or femoral cartilage injury area >2 cm2.

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.

Three-Dimensional Computed Tomography Reconstructions May Detect Pincer Lesions With Higher Sensitivity Than Radiographs in Patients With Femoroacetabular Impingement Syndrome

To assess the diagnostic capability of radiographs (XRs) to detect pincer lesions compared with 3-dimensional (3D) computed tomography scans in patients undergoing hip arthroscopy for femoroacetabular impingement syndrome (FAIS). We performed a retrospective review of all patients who underwent hip arthroscopy for FAIS between September 1, 2020, and October 2, 2022. Preoperative imaging was reviewed. Pincer lesions were defined as a lateral center-edge angle greater than 40°; a Tönnis angle greater than 0°; the presence of the ischial spine, crossover, or posterior wall sign; and the presence of overcoverage greater than 80%. Under "select criteria," patients were classified as having a pincer lesion on XRs and 3D computed tomography reconstructions (CTRs) based on the lateral center-edge angle or Tönnis angle alone, whereas "all criteria" added the presence of the crossover sign and coverage percentage. Statistical analysis was performed to determine the diagnostic accuracy of XRs compared with 3D CTRs. A total of 69 patients met the inclusion criteria. There were 21 male patients (30.4%) and 48 female patients (69.6%). The mean age was 33 ± 13.5 years. χ2 Analysis for select criteria found that 3D CTR was more likely than XRs to detect a pincer lesion. χ2 Analysis for all criteria found that 3D CTR was more likely than XRs to detect a pincer lesion. χ2 Analysis further showed that when using XRs, a pincer lesion was more likely to be detected under all criteria than under select criteria. Likewise, when using 3D CTR, a pincer lesion was more likely to be detected under all criteria than under select criteria. In this study, we found that 3D CTR detected pincer lesions in patients undergoing hip arthroscopy for FAIS with significantly higher sensitivity than XRs alone. Level III, retrospective cohort study.

Low osteotomy cut of Dega procedure for older children with developmental dysplasia of the hip.

The effect on acetabular management in developmental dysplasia of the hip (DDH) patients aged 7 or older with modified low Dega osteotomy procedure was evaluated. Patients between 7 and 14 years old were managed with modified low Dega osteotomy and open reduction and concomitant procedures to evaluate whether low level osteotomy improved the clinical and radiologic outcomes after treatment. Clinical status was assessed using the modified McKay's criteria; radiologic evaluations were assessed for the modified Severin classification, the mean acetabular index (AI), Sharp angle and center-edge (CE) angle. And occurrence of triradiate cartilage injury and complications was recorded. Forty-two DDH patients (57 hips) between 7 and 14 years old were managed with modified low Dega osteotomy. The results demonstrated the latest follow-up 43 hips (75.4%) were rated excellent and 10 hips (17.5%) rated good according to the modified McKay criteria and 41 hips (71.9%) were rated excellent and 11 hips (19.3%) rated good according to Modified Severin classification, respectively. The mean Hip Score improved from 69.53 ± 7.14 before the operation to 93.17 ± 8.43 at the final follow-up. The mean AI changed from 31.9° to 20.2°, mean Sharp angle decreased from 59.3° to 38.8° and mean CE angle increased from -10.9° to 35.2°, preoperatively and at latest follow-up, respectively. The modified low Dega osteotomy combined with open reduction and concomitant procedures were found to be adequate in improving instant and sustained clinical and radiographic outcomes for the late detected pediatric walking DDH patients.

Computer simulation study of cementless cup placement for dysplastic hip osteoarthritis using subluxation percentage of Crowe classification.

It is often difficult to achieve adequate bone coverage of the cup in total hip arthroplasty in cases of severe developmental dysplasia of the hip (DDH). This study aimed to evaluate the relationship between subluxation percentage of Crowe classification and cup center-edge (cup-CE) angle to investigate whether subluxation percentage according to the Crowe classification is a useful indicator for cementless cup placement. Cementless cup placement was simulated in 77 women with DDH in 91 hips (Crowe I, 35 hips; Crowe II, 35 hips; and Crowe III, 21 hips) using computed tomography-based computer simulation software. The cups were placed at the anatomic hip center (AHC) and 10-mm high hip center (HHC). The relationship between the subluxation percentage and cup-CE angle was evaluated using Spearman's rank correlation coefficient. In addition, the cutoff values for the subluxation percentage that satisfied a cup-CE angle ≥0° were determined using the receiving operating characteristic curve. The cup-CE angle was negatively correlated with the subluxation percentage in both AHC and 10-mm HHC (correlation coefficient ρ = -0.542 [p < 0.01] and -0.704 [p < 0.01], respectively). The cutoff values for subluxation percentage that satisfied a cup-CE angle ≥0° were 56.1% and 73.6% for AHC and 10-mm HHC, respectively. Cementless cup placement in AHC is difficult in cases with the subluxation percentage ≥56.1%, and HHC reconstruction or femoral structural autograft technique should be considered as an alternative. Moreover, placement at 10 mm above AHC is difficult in cases with subluxation percentage ≥73.6%.

Functional and radiological outcomes of periacetabular osteotomy for hip dysplasia in patients under fifty years using a minimally invasive approach—a single surgeon series with a minimum follow up of two years

PurposeWe conducted a retrospective analysis of prospectively collected data to evaluate (1) the extent of surgical correction following minimally invasive periacetabular osteotomy, (2) improvements in functional outcomes and any potential predictors for favourable outcome, and (3) complications after minimally invasive periacetabular osteotomy.MethodsA total of 352 minimally invasive periacetabular osteotomy procedures were performed on 312 hip dysplasia patients between 2013 and 2020. Radiological parameters such as lateral centre edge angle, acetabular index, and Tönnis grade of arthritis were calculated. Patients also completed a range of patient reported outcome measures. Wilcoxon signed-rank tests were performed to assess for differences between patient reported outcome measures and radiological outcomes across the follow-up periods. Univariate linear regression and logistic regression were used to assess for predictors of change in functional outcome.ResultsPatients had a significant correction in mean lateral centre edge angle from 17.2° to 35.3° (p < 0.001) and mean acetabular index from 13.2° to − 0.82°. At one year follow-up all patient reported outcome measures were significantly greater than their baseline measurements and this improvement was maintained at two years. Changes in patient reported outcome measures were independent of radiological parameters such as change in the lateral centre edge angle and acetabular index, pre-operative Tönnis grade, and patient factors such as age and sex. A total of 5.11% of patients developed post-operative complications, with four requiring posterior column fixation. Four patients (1.12%) needed a total hip replacement.ConclusionMinimally invasive periacetabular osteotomy is a safe procedure that provides significant functional outcome improvements following surgery at six months which is maintained at two years. More than three-fourths of patients achieved improvement of iHOT-12 score beyond the minimal clinically important difference and more than half of the patients achieved substantial clinical benefit for iHOT-12 score.

Association Between Anterior Hip Capsule Thickening and Sagittal Pelvic Alignment Among Patients With Developmental Dysplasia of the Hip.

The pathogenesis and pathology of secondary osteoarthritis (OA) of the hip, which is mainly due to developmental dysplasia of the hip (DDH), in Japan are obscure. There are some reports on the thickening of the hip capsule, but the relationship between the thickness of the hip capsule and the pelvic alignment due to hip deformity is not well known. This research investigated whether the capsular thickness of female DDH patients was related to pelvic alignment. This single-center cross-sectional study included female patients aged 50-79 years (n=13) who had undergone primary total hip arthroplasty (THA) due to secondary hip OA with a background of DDH. The part of the hip capsule including the iliofemoral ligament was resected and measured directly with a digital caliper. The Sharp angle, center-edge (CE) angle, sacral slope (SS), pelvic tilt (PT), pelvic incidence (PI), and lumbar lordosis angle (LLA) were measured with an X-ray image to investigate the relationship between the capsular thickness and the pelvic posture. Pearson's correlation coefficient showed a negative correlation between hip capsular thickness and Sharp angle (r=-0.57, p>0.05). No significant correlation was found between the thickness of the hip capsule and the sagittal X-ray parameters including SS, PT, PI, LLA, and CE angle in the coronal plane. The thickness of the hip capsule is moderately associated with the Sharp angle on the coronal plane. The results of this study suggest that the thickness of the joint capsule does not necessarily relate to the degenerative process among patients with DDH and the process can be complex to apply two-dimensional postural indices for the explanation.

Outcome of Open Hip Reduction, Pelvic Osteotomy, and Varus Derotational Osteotomy in Children With Cerebral Palsy: A Retrospective Study.

Introduction For spastic hip dislocations, a variety of operations are available with open hip reduction and varus derotational osteotomy of the proximal femur combined with pelvic osteotomy ± adductor release being a good option with favourable outcomes. This study aims to assess the outcome and complications of combined open hip reduction with pelvic osteotomy and varus derotational osteotomy. Methods In this study, 70 hips in 52 patients with spastic hip dislocation due to cerebral palsy were included. All included patients were treated surgically in our institute between January 2016 and December 2021. There were 31 males and 21 females. For each patient, information was collected about the age at the time of surgery and different radiological parameters at three different time intervals: pre-operatively, immediately post-operatively, and at the final follow-up. We also collected information about any complications arising from the surgery performed. Results The mean duration of follow-up was 19.58 months. The acetabular index decreased from an average of 35.01° to 17.18° with a mean difference of 17.83° (p<0.001). The central edge angle, which averaged -49.13° in the pre-operative period, increased to 26.34° and then marginally decreased to 25.47° at the final follow-up. The average migration indexof 80.51% in the pre-operative period improved to 1.4% post-operatively with a mean difference of -79.11% (p<0.01). The migration index increased to 8.54% at the final follow-up. Similarly, the neck-shaft angle, which averaged 160.89° in the pre-operative period, decreased to 125.23° at the time of final follow-up with a percentage change of -22.16%. Conclusion Single-stage combined surgery in the form of combined open hip reduction and pelvic osteotomy with varus derotational osteotomy successfully treats the condition and shows good outcomes in patients with spastic hip dislocations. This treatment is associated with very few complications.

Application of deep learning for automated diagnosis and classification of hip dysplasia on plain radiographs

BackgroundHip dysplasia is a condition where the acetabulum is too shallow to support the femoral head and is commonly considered a risk factor for hip osteoarthritis. The objective of this study was to develop a deep learning model to diagnose hip dysplasia from plain radiographs and classify dysplastic hips based on their severity.MethodsWe collected pelvic radiographs of 571 patients from two single-center cohorts and one multicenter cohort. The radiographs were split in half to create hip radiographs (n = 1022). One orthopaedic surgeon and one resident assessed the radiographs for hip dysplasia on either side. We used the center edge (CE) angle as the primary diagnostic criteria. Hips with a CE angle < 20°, 20° to 25°, and > 25° were labeled as dysplastic, borderline, and normal, respectively. The dysplastic hips were also classified with both Crowe and Hartofilakidis classification of dysplasia. The dataset was divided into train, validation, and test subsets using 80:10:10 split-ratio that were used to train two deep learning models to classify images into normal, borderline and (1) Crowe grade 1–4 or (2) Hartofilakidis grade 1–3. A pre-trained on Imagenet VGG16 convolutional neural network (CNN) was utilized by performing layer-wise fine-turning.ResultsBoth models struggled with distinguishing between normal and borderline hips. However, achieved high accuracy (Model 1: 92.2% and Model 2: 83.3%) in distinguishing between normal/borderline vs. dysplastic hips. The overall accuracy of Model 1 was 68% and for Model 2 73.5%. Most misclassifications for the Crowe and Hartofilakidis classifications were +/- 1 class from the correct class.ConclusionsThis pilot study shows promising results that a deep learning model distinguish between normal and dysplastic hips with high accuracy. Future research and external validation are warranted regarding the ability of deep learning models to perform complex tasks such as identifying and classifying disorders using plain radiographs.Level of EvidenceDiagnostic level IV

Primary Hip Arthroscopy in Patients With Acetabular Dysplasia: A Systematic Review of Published Clinical Outcomes at Minimum 5-Year Follow-up

Background: Hip arthroscopy in patients with borderline hip dysplasia has satisfactory outcomes at short-term follow-up; however, the data on midterm outcomes are inconsistent, and failure rates are high in some studies, limiting understanding of the role and utility of hip arthroscopy in this patient cohort. Purpose: To provide an up-to-date, evidence-based review of the clinical outcomes of primary hip arthroscopy in patients with frank or borderline hip dysplasia at ≥5-year follow-up and report the failure rate and progression to total hip arthroplasty in this cohort. Study Design: Systematic review; Level of evidence, 4. Methods: A comprehensive literature search was performed according to the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. Studies were included if they evaluated outcomes of primary hip arthroscopy in patients with lateral center-edge angle (LCEA) <25° at ≥5-year follow-up. Risk of bias assessment was performed using the methodological index for non-randomized studies scoring system. Level of evidence was determined using criteria from the Oxford Centre for Evidence-Based Medicine. Results: Nine studies were included in this review. Patients with LCEA <25° demonstrated satisfactory clinical outcomes, high patient satisfaction, and significant postoperative improvements in patient-reported outcomes (PROs) at follow-up ranging from a ≥5 to 10 years. Studies comparing patients with dysplasia to those without did not demonstrate significant differences in preoperative, postoperative, or delta PROs or in failure, reoperation, or revision rates. There was no overall significant correlation between outcomes and LCEA stratification. Conclusion: Hip arthroscopy in carefully selected patients with LCEA <25° can be successful at mid- to long-term follow-up and may provide clinical outcomes and failure rates comparable with patients with normal LCEA, understanding that this is a singular, 2-dimensional radiographic measure that does not differentiate instability from impingement or combinations thereof, warranting future studies delineating these differences. These findings suggest that hip dysplasia may not be an absolute contraindication for isolated hip arthroscopy and may serve as a viable intervention with consideration of staged future periacetabular osteotomy (PAO). Importantly, this review does not suggest that hip arthroscopy alters the natural history of dysplasia; therefore, patients with dysplasia should be counseled on the potential utility of PAO by appropriate hip preservation specialists.

Multivariate linear-mixed analysis of changes in anterior inferior iliac spine impingement incidence with posterior pelvic tilt: a computer simulation study.

It is well known that increased posterior tilt of the pelvis is an effective strategy for avoiding impingement of the femur with the pelvis during movement. Daily repetitive collisions become mechanical loads, and the more frequently they occur, the more tissue damage and pain they cause. Therefore, reducing the rate of occurrence of impingement is important to avoid aggravation of symptoms. This study aimed to evaluate the effects of changes in posterior pelvic tilt on the risk of impingement between the femur and the anterior inferior iliac spine (AIIS)/subspine in various functional postures. Patients with femoroacetabular impingement syndrome (FAIS) who were candidates for hip arthroscopic osteochondroplasty between October 2013 and June 2020 were included. A three-dimensional reconstructed model was used to simulate the incidence of impingement at 12 hip positions required for activities of daily living. We predicted value of the spatial incidence of impingement assumed that hip motion should exceed 130/30 degrees without impingement. Impingement was measured at three pelvic positions: an anterior tilt of 10°, in the functional pelvic plane and a posterior tilt of 10°. Multivariate linear-mixed models were used to assess the effect of covariate-adjusted posterior pelvic tilt on the impingement incidence in the AIIS region. AIIS type, center-edge angle, acetabular version and femoral version were used as covariates. The impingement rates and locations of the three pelvic tilt postures were assessed. Seventy-eight patients (60 males and 18 females; average age, 46 ± 15.1 years) with FAIS were analyzed. A multivariate linear-mixed model revealed a coefficient of -0.8% (95% confidence interval -0.9 to -0.7%; P < 0.001) for posterior pelvic tilt. Thus, posterior pelvic tilt affects AIIS impingement incidence. After adjusting for anatomical effects, the posterior pelvic tilt should be addressed to avoid impingement.

Patients with Borderline Hip Dysplasia Undergoing Primary Hip Arthroscopy for Femoroacetabular Impingement Syndrome Demonstrate Lower Outcome Scores but Comparable Survivorship to Non-Dysplastic Controls: A Propensity-Matched Study with Minimum 10-Year Follow-up

Background: Patients with borderline hip dysplasia (BHD) have demonstrated similar outcomes following primary hip arthroscopy for femoroacetabular impingement syndrome (FAIS) compared to equivalent patients without dysplasia at short- and mid-term follow-up. However, outcomes in these groups have not yet been compared at long-term follow-up. Objectives: To compare long-term clinical outcomes following primary hip arthroscopy for FAIS between patients with BHD and non-dysplastic matched controls. Methods: A retrospective review was conducted of patients who underwent primary hip arthroscopy for FAIS from January 2012 through February 2013. Patients with BHD, defined as a lateral center edge angle (LCEA) between 18° and 25°, were propensity matched in a 1:3 ratio by sex, age, and body mass index (BMI) to non-dysplastic controls. Preoperative and postoperative radiographs were assessed. Patient-reported outcomes (PROs) were collected preoperatively and 10 years postoperatively, and achievement rates of Minimal Clinically Important Difference (MCID) and Patient-Acceptable Symptom State (PASS) were calculated. PRO measures included the Hip Outcome Score Activities of Daily Living (HOS-ADL) and Sports-Specific (HOS-SS) subscales, modified Harris Hip Score (mHHS), 12-item international Hip Outcome Tool (iHOT-12), and Visual Analog Scales (VAS) for Pain and Satisfaction. Gross survivorship was assessed using Kaplan-Meier curves. PROs, MCID and PASS achievement rates, and survivorship were compared between groups. Results: Twenty-eight patients with BHD (71.4% female; age: 30.8 ± 10.8 years, BMI: 24.2 ± 3.9 kg/m2) were matched to 84 controls (66.7% female, age: 34.4 ± 10.5 years, BMI: 24.9 ± 5.1 kg/m2; p ≥ 0.135). Mean follow-up was 10.3 ± 0.3 years. There were no significant differences between groups in any demographic characteristics, radiographic measurements, or intraoperative findings (p ≥ 0.096), except pre- and post-operative LCEA and Tönnis angle, which were lower and higher, respectively, among BHD patients (p &lt; 0.001). Both groups demonstrated significant improvement in all PROs between the preoperative and 10-year postoperative time points (p &lt; 0.001 for all). Preoperative, 10-year postoperative, and magnitude of change (delta) in PRO scores were similar between groups for all measures (p ≥ 0.072), except 10-year postoperative HOS-SS (BHD: 62.9 ± 31.9 vs. Controls: 80.1 ± 26.0, p = 0.030) and change in VAS Pain (BHD: -34.2 ± 27.2 vs. Controls: -48.5 ± 26.1, p = 0.047). Rates of MCID achievement were similar between groups for all PRO measures, but rates of PASS achievement were significantly lower among BHD patients for HOS-ADL (BHD: 39.1% vs. Controls: 77.4%, p = 0.002), HOS-SS (BHD: 45.5% vs. Controls: 84.7%, p = 0.001), and VAS Pain (BHD: 50.0% vs. Controls: 78.5%, p = 0.015). There was no difference in reoperation rate between groups (BHD: 14.3% vs. Controls: 17.9%, p = 0.778). Kaplan-Meier survival analysis demonstrated comparable gross survivorship at long-term follow-up (p = 0.645). Conclusions: Patients with BHD undergoing primary hip arthroscopy for FAIS demonstrated significantly lower sports-specific PRO scores than propensity-matched controls at 10-year follow-up, with a trend toward significantly worse scores for measures assessing activities of daily living, pain, and satisfaction. Rates of MCID achievement were similar between groups, but BHD patients demonstrated lower rates of PASS achievement for the majority of PRO measures. However, patients with BHD had similar long-term hip survivorship compared to controls, with no significant differences in rates of revision hip arthroscopy or conversion to total hip arthroplasty.

Decision-making in borderline hip dysplasia and concomitant femoracetabular impingement syndrome: using a discrete choice experiment to explore patient preferences

ABSTRACT Decision-making regarding surgical treatment of patients showing radiographic evidence of femoroacetabular impingement syndrome (FAIS) in the setting of borderline hip dysplasia (BHD) remains a challenge as there is no consensus on treatment in current literature. When medical evidence is unclear, understanding patient preferences becomes particularly important in deciding the optimal treatment for each patient. The purpose of this study was to measure the patient-determined importance of factors surrounding surgical treatment of FAIS in BHD. Patients aged 18–65 with hip pain and BHD (defined as lateral center edge angle 18–25 or Tonnis angle 10–15) morphology were given a discrete-choice experiment (DCE) focusing on attributes that differ between treatment options: Length of Hospital Stay, Major Complication Rate, Chance of Needing Reoperation within 2 Years and Time to Return to Regular Exercise. This DCE was used to calculate treatment preferences, relative attribute importance and preference weights. A total of 101 patients fully completed the DCE. The most important attribute (average importance weight, 95% CI) was Chance of Reoperation (60.16, 56.99–63.34), while the least important was Hospital Stay (6.57, 5.73–7.41). Only 6 Months to Resume Regular Exercise and 2% Chance of Reoperation (P &amp;lt; 0.05) significantly impacted treatment choice. When presented with fixed choice parameters, 50.5% of subjects preferred PAO and arthroscopy while 49.5% opted for arthroscopy alone. When no clear surgical treatment is indicated, patient preferences have an amplified role in patient decision-making. Our results confirm variation in attribute importance within treatments as well as treatment choice, highlighting the importance in understanding patient preferences in decision-making for FAIS in BHD. More patient-specific generalizable outcomes of surgical treatment options are needed in the literature.

Ultrasound had high accuracy in measuring hip joint capsule thickness

BackgroundThe hip joint capsule is an essential component of hip joint function and stability, and its thickness is closely associated with certain medical conditions, surgical outcomes, and rehabilitation treatments. Currently, in clinical practice, hip joint capsule thickness is predominantly measured using magnetic resonance imaging (MRI), with limited utilization of ultrasound examinations for this purpose.MethodsWe retrospectively evaluated patients who visited our Sports Medicine Department between February 2017 and March 2023 and underwent both hip joint MRI and ultrasound imaging on the same side. All patients had undergone preoperative hip joint MRI and ultrasound examinations, with the time gap between the two examinations not exceeding three months. Measurements of hip joint capsule thickness were taken on both MRI and ultrasound images for the same patients to analyze their consistency. Additionally, we measured the alpha angle, lateral center-edge angle, acetabular anteversion angle, and femoral anteversion angle of the patients’ hip joints and analyzed their correlation with hip joint capsule thickness measure by ultrasound.ResultsA total of 307 patients were included in this study, with hip joint capsule thickness measured by MRI and ultrasound being 5.0 ± 1.2 mm and 5.0 ± 1.5 mm, respectively. The Bland-Altman analysis demonstrates good agreement or consistency. The paired t-test resulted in a p-value of 0.708, indicating no significant statistical difference between the two methods. The correlation analysis between acetabular anteversion angle and ultrasound-measured capsule thickness yielded a p-value of 0.043, indicating acetabular anteversion angle and capsular thickness may have negative correlation.ConclusionsThe measurements of joint capsule thickness obtained through ultrasound and MRI showed good consistency, suggesting that ultrasound can be used in clinical practice as a replacement for MRI in measuring hip joint capsule thickness. There was a significant correlation between acetabular anteversion angle and hip joint capsule thickness, indicating potential for further research in this area.