Femoral Head Coverage Research Articles

Quantitative assessment of hip morphology to enhance the identification of hip dysplasia in German Shepherd Dogs

To develop quantitative measures that, when combined with the Fédération Cynologique Internationale (FCI) score, would potentially enhance the accuracy of the scoring process. 153 client-owned purebred German Shepherd Dogs with normal and near normal (71 dogs) and dysplastic coxofemoral joint (82 dogs). Center edge (CE) angle, Norberg angle (NA), indexes of dorsal acetabular femoral head (AFH) coverage width and area, acetabular index angle, and inclination angle were determined. We also investigated the correlation between selected variables. Coxofemoral joints were classified into normal, near normal, and mildly, moderately, and severely dysplastic joints based on the morphometric criteria previously established by the conventional FCI scoring. Variables were compared among the 5 groups using ANOVA. Linear relationships were determined using Spearman correlation coefficients. All radiographic measurements differed significantly (P < .0001) among the 5 assigned groups (normal, near normal, mildly dysplastic, moderately dysplastic, and severely dysplastic hip joints). NA was the only measure that differed significantly (P ≤ .03) between the 5 assigned groups. Positive correlations were identified between Norberg and CE angles (rs = 0.93), between width and area indexes of dorsal AFH coverage (rs = 0.92), and between the measurement techniques utilized to assess lateral versus dorsal AFH coverage (rs ≥ 0.65). Evaluation of lateral and dorsal AFH coverage may help to refine the scoring system used to select German Shepherd Dogs for breeding. German Shepherd Dogs with NA < 103°, CE angle < 20.8°, dorsal AFH coverage width index ≤ 49%, and/or dorsal AFH coverage area index ≤ 51% should be considered to have mild, moderate, or severe hip dysplasia and are therefore not good candidates for breeding. Borderline values between near normal and mildly dysplastic joints should be reevaluated.

The Role of Femoral Head Size and Femoral Head Coverage in Dogs with and without Hip Dysplasia.

The subject of hip dysplasia in dogs is still current and preoccupies both animal owners and veterinarians. Major factors affecting the development of the disorder are hip laxity and incongruent joints. Many studies on etiology, pathogenesis, and early diagnosis have been performed to reduce prevalence and select healthy dogs for breeding. The purpose of the present study was to investigate a possible relationship between dysplasia and femoral head area (FHA), femoral coverage by the acetabulum (CFH) and cranio-caudal distance of the dorsal acetabular rim (CrCdAR). Radiographs of a total of 264 skeletally mature dogs with similar physical characteristics (German wirehaired pointers (GWP), German shepherd dogs (GSD) and Labrador retrievers (LAB)) presented for routine hip dysplasia screening were recruited for the study. FHA, CFH and CrCdAR were measured and related to dysplasia status. Evaluations of FHA (p = 0.011), CFH (p < 0.001) and CrCdAR length (p = 0.003) measurements revealed significant interactions between breed, sex and FCI scores, so they had to be assessed separately. The results revealed that FHA tends to decrease as the hip dysplasia score worsens. There was no significant relationship between FHA and dysplasia assessment. FHA is breed-specific and is larger in normal and near-normal male (p = 0.001, p = 0.020) and female (p = 0.001, p = 0.013) GWP compared to GSD, respectively. FHA is greater in normal male GWP (p = 0.011) and GSD (p = 0.040) compared to females. There was a significant and strong positive correlation between FHA and CrCdAR in all breeds and sexes. Additionally, FCI scoring had a medium (GWP, GSD) to strong (LAB) negative correlation with CFH.

High Survivorship and Comparable Patient-Reported Outcomes at a Minimum 5 Years After Hip Arthroscopic Surgery in Patients With Femoroacetabular Impingement, With and Without Lateral Rim Dysplasia

Background: Femoroacetabular impingement (FAI) in patients with dysplasia presents a unique challenge to surgeons. Short-term outcomes are conflicting, while longer term follow-up data are only emerging. Purpose: To quantify midterm (minimum 5-year follow-up) outcomes after the arthroscopic correction of FAI in the presence of lateral rim dysplasia compared with a matched control group with FAI with normal acetabular coverage. Study Design: Cohort study; Level of evidence, 3. Methods: Prospective outcome data, collected in a consecutive series of patients undergoing arthroscopic FAI correction with lateral rim dysplasia (lateral center-edge angle [LCEA] of 13°-25°), were reviewed (N = 75 cases). An age- and sex-matched control group of 120 cases was also formed (LCEA >25°). Survivorship was defined as the avoidance of total hip replacement and assessed using a Kaplan-Meier curve with the log-rank test. Survival rates and patient-reported outcome measure (PROM) scores (modified Harris Hip Score [mHHS], University of California, Los Angeles [UCLA], 36-Item Short Form Health Survey [SF-36], and Western Ontario and McMaster Universities Osteoarthritis Index [WOMAC] preoperatively and at 5 years postoperatively) were compared between the groups. The proportion of patients across groups achieving the minimal clinically important difference (MCID) was compared for each PROM. The dysplasia group was also analyzed independently to identify any factors that may indicate a less favorable outcome using regression analysis. The group was divided into 2 subgroups: borderline dysplasia (LCEA of 20°-25°) and severe dysplasia (LCEA <20°). Results: The survival rate in the dysplasia group was 97%. There was no statistical difference with respect to survival rates or any PROM scores (P > .05 for all) between the groups. There were similar rates of achieving the MCID between the groups for the mHHS, UCLA, and WOMAC. The FAI control group had a higher rate of achieving the MCID for the SF-36 (P = .012; effect size = 0.274 [small]). Subgroup analysis indicated a lower survival rate (78% vs 100%, respectively; P < .001) in female cases in the dysplasia group (n = 9) compared with male cases in the dysplasia group (n = 66). The UCLA score in female cases in the dysplasia group at 5 years was statistically lower compared with that in male cases in the dysplasia group (6 vs 10, respectively; P = .003; effect size = 0.378 [medium]), but no other outcome revealed any differences between the sexes. There were also no variables identified on regression analysis that accurately predicted a poorer outcome in the dysplasia group. When stratified by severity, there was no difference in survivorship or outcomes between those with severe dysplasia (LCEA <20°; n = 11) and those with borderline dysplasia (LCEA of 20°-25°; n = 64). Conclusion: An arthroscopic intervention was a successful treatment option for FAI in the presence of lateral rim dysplasia at midterm follow-up. Irrespective of the severity of dysplasia, patients can expect similar improvements to those in patients with normal femoral head coverage.

Predictors of residual hip dysplasia in 12-18-month-old vs. over 18-month-old DDH patients after closed reduction and the reliability of one residual hip dysplasia criterion: a retrospective cohort study.

The diagnostic and prediction criteria of residual hip dysplasia (RHD) remains controversial. There were no studies that focused on the risk factors of RHD after closed reduction (CR) in children with developmental dislocation of the hips (DDH) over 12 months of age. In this study, we assessed the percentage of RHD in DDH patients aged 12 to 18 months vs. that in DDH patients aged over 18 months after CR and determine the predictors of RHD. Meanwhile, we tested the reliability of our RHD criteria compared with Harcke standard. Patients over 12 months of age who underwent successful CR from October 2011 to November 2017 and followed up for at least 2 years were enrolled. Gender, affected side, age at CR and follow-up time were recorded. Acetabular index (AI), horizontal acetabular width (AWh), center-to-edge angle (CEA), and femoral head coverage (FHC) were measured. The cases were divided into two groups according to whether older than 18 months. RHD was determined according to our criteria. A total of 82 patients (107 hips) were included, including 69 females (84.1%), 13 males (15.9%), 25 patients (30.5%) with bilateral DDH, 33 patients (40.2%) with left side, 24 patients (29.3%) with right side, 40 patients (49 hips) with age 12-18 months, and 42 patients (58 hips) with age >18 months. At a mean follow-up of 47.8 [24-92] months, the percentage of RHD was higher in patients >18 months of age (58.6%) than patients 12-18 months of age (40.8%), but the difference was not statistically significant. Binary logistic regression analysis showed that pre-AI, pre-AWh, and improvement in AI and AWh (P=0.025, 0.016, 0.001, 0.003, respectively) had significant difference. The sensitivity and specialty of our RHD criteria were 81.82% and 82.69%, respectively. For patients with DDH over 18 months, CR is still a choice. We documented four predictors of RHD, suggesting that we should focus on the developmental potential of an individual's acetabulum. Our RHD criteria may be one of the reliable and useful tools in clinical practice to help determine whether to perform continuous observation or surgery, but further research is needed due to limited sample size and follow-up time.

What is the agreement between intraoperative fluoroscopy and postoperative radiographs in Bernese periacetabular osteotomy?

BackgroundIt is important to reorient the acetabular fragment into an optimal position and version to ensure a good long-term outcome after Bernese periacetabular osteotomy (PAO). Unfortunately, the intraoperative balance between overcorrection and undercorrection remains challenging for the surgeon. The purpose of this study was to answer two questions: (1) Does the femoral head coverage measured on intraoperative fluoroscopy agree with that measured on postoperative radiography? (2) What is the reliability of intraoperative fluoroscopy in identifying hip center correction in PAO?MethodsA total of 173 patients (173 hips) who underwent PAO for developmental dysplasia of the hip (DDH) at our center from July 01, 2020, to December 31, 2020, were retrospectively reviewed. Imaging data from 111 patients (female/male, 98/13; right/left, 72/39; mean age, 28.93 years) were included in this study. The analysis included measurement of the lateral center-edge angle (LCEA), acetabular index (AI), anterior wall index (AWI), posterior wall index (PWI), extrusion index (EI), and medial offset distance (MO). These measurements were acquired from intraoperative fluoroscopic images and postoperative radiographs and compared by paired t test using SPSS (version 24.0). Significance was determined at a p value of < 0.05. Bland–Altman analysis, conducted using GraphPad Software (version 9), was used to quantify the agreement between intraoperative fluoroscopic images and postoperative radiographs.ResultsThe means (standard deviations, SDs) of the LCEA, AI, AWI, PWI, EI, and MO obtained on intraoperative fluoroscopy were 32.86° (5.73°), 0.66° (5.55), 0.29 (0.10), 0.75 (0.17), 11.15% (6.50%), and 8.49 mm (3.68 mm), respectively. On postoperative radiography, the corresponding values were 32.91° (6.31°), 1.63° (5.22°), 0.29 (0.15), 0.85 (0.14), 11.27% (7.36%), and 9.60 mm (3.79 mm). The differences in the LCEA, AWI, and EI acquired from intraoperative fluoroscopic images and postoperative radiographs were not significant (p = 0.90, 0.95, and 0.83, respectively), but those in the AI, PWI, and MO were significant (p < 0.05). The mean biases (95% limits of agreement) of the LCEA, AI, AWI, PWI, EI, and MO were − 0.04 (− 6.85), − 0.97 (− 7.78), 0 (− 0.30), − 0.11 (− 0.36), − 0.12 (− 11.92), and − 1.11 (− 5.51), respectively.ConclusionThe LCEA, EI, and AWI can be used to reliably predict postoperative femoral head coverage at the level of 2D graphics. Acetabular inclination can be cautiously assessed using AI on intraoperative fluoroscopy. In the absence of intraoperative 3D image evaluation, the AWI and PWI demonstrate acceptable agreement between fluoroscopy and radiography in assessing the acetabular version. Although the MO shows slight bias, it can be helpful in properly positioning the acetabulum during PAO.

Results of Arthroscopic Treatment for Femoroacetabular Impingement

Background. Femoroacetabular impingement (FAI) is one of the most frequent causes of hip pain and limited hip mobility in young and middle-aged patients. It is a result of repeated injury of hip structures, that leads to degenerative changes in hip labrum, cartilage and subchondral bone and provokes progressive development of hip osteoarthritis.&#x0D; Aim of study to analyze own experience of treating patients with femoroacetabular impingement and identify factors affecting its outcomes.&#x0D; Methods. Retrospective, uncontrolled, single-center clinical study included 128 patients with FAI which had 150 surgeries on 149 joints in in the period from 2013 to 2021. All patients underwent physical examination and X-ray diagnostics, their FAI type was identified. The alpha angle of external part of femoral head in anterior-posterior position and in the modified Dunn 45 position, as well as Tonnis angle, lateral central-marginal angle in Ogata modification and the height of articular gap along the lateral (LS) and medial edges (MS) of sclerosed acetabulum part were calculated. The i-HOT-33 and HOS scales were used to assess preoperative status and postoperative results.&#x0D; Results. The average follow-up period was 3.9 years (SD 1.71; min 1.05 and max 8.16). The study included 55 (43.0%) women and 73 (57.0%) men which underwent 64 (42.7%) and 86 (57.3%) surgeries respectively. The most common types of FAI, according to our data, were mixed type (53% of joints) and сam type (27.5% of joints). Insufficient coverage of the femoral head by the acetabulum (borderline dysplasia) in combination with the сam deformity of the femoral head was observed in 18.1%. Pincer-type FAI was observed in 1.4% of joints. We obtained the worst results with a combination of сam deformity and borderline dysplasia in comparison with cam- and mix-type FAI according to the i-HOT-33 and HOS scales. Patients age, deep cartilage damage, irreparable labrum damage and height decrease of the lateral part of the articular gap determined negative effect on treatment results according to the i-HOT-33 and HOS scales.&#x0D; Conclusion. Hip arthroscopy showed good short- and midterm outcomes in patients with FAI. Pain syndrome is most often manifested in patients with pathology of hip soft tissue structures concomitant to FAI. The combination of сam deformity and insufficient femoral head coverage, deep cartilage damage and a height decrease of the articular gap are important predictors of poor treatment results.

Do patients with femoroacetabular impingement syndrome who undergo hip arthroscopy display improved alpha angle (magnetic resonance imaging) and radiographic hip morphology?

To compare (a) the change in radiological bony morphology between participants with femoroacetabular impingement (FAI) syndrome who underwent arthroscopic hip surgery compared to physiotherapist-led non-surgical care and (b) the change in radiological bony morphology between participants with FAI syndrome who underwent arthroscopic hip surgery involving cam resection or acetabular rim trimming or combined cam resection and acetabular rim trimming. Maximum alpha angle measurements on magnetic resonance imaging and Hip2 Norm standardized hip measurements on radiographs were recorded at baseline and at 12 months postoperatively. One-way analysis of covariance and independent T tests were conducted between participants who underwent arthroscopic hip surgery and physiotherapist-led non-surgical care. Independent T tests and analysis of variance were conducted between participants who underwent the 3 different arthroscopic hip procedures. Arthroscopic hip surgery resulted in significant improvements to mean alpha angle measurements (decreased from 70.8° to 62.1°) (P value < .001, 95% CI -11.776, -4.772), lateral center edge angle (LCEA) (P value=.030, 95% CI -3.403, -0.180) and extrusion index (P value=0.002, 95% CI 0.882, 3.968) compared to physiotherapist-led management. Mean maximum 1-year postoperative alpha angle was 59.0° (P value=.003, 95% CI 4.845, 18.768) for participants who underwent isolated cam resection. Measurements comparing the 3 different arthroscopic hip procedures only differed in total femoral head coverage (F[2,37]=3.470, P=.042). Arthroscopic hip surgery resulted in statistically significant improvements to LCEA, extrusion index and alpha angle as compared to physiotherapist-led management. Measured outcomes between participants who underwent cam resection and/or acetabular rim trimming only differed in total femoral head coverage.

Prediction of Late Dysplasia Based on Ultrasound and Plain X-Ray at 6 Months.

Developmental dysplasia of the hip represents a spectrum of deformity. Residual dysplasia at 2 years of age is associated with an increased risk for osteoarthritis and functional limitations. We compared the prognostic value of 6-month imaging modalities and aimed to identify optimal diagnostic metrics for the prediction of residual dysplasia. After IRB approval, patients who underwent Pavlik treatment between 2009 and 2018 with 2-year follow-up were identified. Sonographs [ultrasound (US)] and radiographs (x-ray) were obtained at 6-month and 2-year-old visits. Dysplasia at 2 years was defined as an acetabular index (AI) >24 degrees. Receiver operating characteristic curves were constructed to quantitatively compare the prognostic ability of US and x-ray-based measures at 6 months. Youden's index [(YI) (values range from 0 (poor test) to 1 (perfect test)] was used to evaluate existing cutoffs at 6 months of age (normal measurements: alpha angle (AA) ≥60 degrees, femoral head coverage (FHC) ≥50%, and AI <30 degrees) relative to newly proposed limits. Fifty-nine patients were included, of which 28.8% of patients (95% CI: 17.3 to 40.4%) had acetabular dysplasia at 2 years. After adjusting for sex, AA [Area under the Curve (AUC): 80] and AI (AUC: 79) at 6 months of age were better tests than FHC (AUC: 0.77). Current diagnostic cutoffs for AA (YI: 0.08), AI (YI: 0.0), and FHC (YI: 0.06) at 6 months had poor ability to predict dysplasia at 2 years. A composite test of all measures based on proposed cutoffs (AA ≥73 degrees, FHC > 62% and AI ≤24 degrees) was a better predictor of dysplasia at 2 years (Youden's index (YI): 0.63) than any single metric. The rate of residual dysplasia remains concerning. The 6-month x-ray and US both play a role in the ongoing management of the developmental dysplasia of the hip. The prediction of dysplasia is maximized when all metrics are considered collectively. Existing parameters were not accurate; We recommend the following cutoffs: AA ≥73 degrees, FHC > 62%, and AI ≤24 degrees. These cutoffs must be validated. Prognostic Level II.

Application of Accepted Use Criteria for the Treatment of Developmental Dysplasia of the Hip Decreases the Number of Infants Treated With a Pavlik Harness.

This analysis examined how the application of the American Academy of Orthopedic Surgeons appropriate use criteria (AUC) for developmental dysplasia of the hip in infants would change treatment patterns and outcomes for Graf IIA hips at a single quaternary pediatric hospital. After Institutional Review Board approval, patient medical records were reviewed and data were collected. Graf IIa hips were defined as alpha angle (AA) 50 to 59 degrees. AA and femoral head coverage (FHC) were measured from initial and 6-month ultrasounds and acetabular index (AI) was measured from radiographs at 6 months of age. Instability (positive Ortolani and Barlow tests) was noted. On the basis of the American Academy of Orthopedic Surgeons AUC for managing developmental dysplasia of the hip, hips were further categorized as normal (FHC ≥45%), borderline (FHC 35% to 44%), or dysplastic (FHC <35%). Overall, 13% (49/371) of Graf IIa hips (AA 50 to 59 degrees) were dysplastic (FHC <35%). Total 24% (89/371) were clinically unstable. Total 42% (37/89) of unstable Graf IIa hips were dysplastic. Only 4% of stable Graf IIa hips were dysplastic (12/282). Out of 371 Graf IIa hips, 256 were treated with Pavlik harness (n=250) or Rhino brace (n=6). Among stable, nondysplastic (SND) hips (those with normal and borderline FHC≥35%), 33% (52/158) were treated because of a more severe contralateral side. If the AUC had been applied, 67% (106/158) of SND Graf IIa hips would not have been treated. Among the n=162 hips that returned for a 6-month radiograph, there was no difference in AI in the 115 treated and 47 untreated SND hips (mean difference treatment vs. no treatment: -1.5, 95% CI, -3.1 to 0.2, P =0.0808). Using AUC recommendations, our center could reduce the number of SND Graf IIa hips we treat by 67%. Although 24% of Graf IIa hips were clinically unstable and 13% were dysplastic based on FHC, most Graf IIa hips had normal or borderline FHC per the AUC and may do well with observation and follow-up ultrasound at 12 weeks old. Level III-diagnostic study.

Normal variation of infant hip development : patterns revealed by 3D ultrasound.

Studies of infant hip development to date have been limited by considering only the changes in appearance of a single ultrasound slice (Graf's standard plane). We used 3D ultrasound (3DUS) to establish maturation curves of normal infant hip development, quantifying variation by age, sex, side, and anteroposterior location in the hip. We analyzed 3DUS scans of 519 infants (mean age 64 days (6 to 111 days)) presenting at a tertiary children's hospital for suspicion of developmental dysplasia of the hip (DDH). Hips that did not require ultrasound follow-up or treatment were classified as 'typically developing'. We calculated traditional DDH indices like α angle (αSP), femoral head coverage (FHCSP), and several novel indices from 3DUS like the acetabular contact angle (ACA) and osculating circle radius (OCR) using custom software. α angle, FHC, and ACA indices increased and OCR decreased significantly by age in the first four months, mean αSP rose from 62.2° (SD 5.7°) to 67.3° (SD 5.2°) (p < 0.001) in one- to eight- and nine- to 16-week-old infants, respectively. Mean αSP and mean FHCSP were significantly, but only slightly, lower in females than in males. There was no statistically significant difference in DDH indices observed between left and right hip. All 3DUS indices varied significantly between anterior and posterior section of the hip. Mean 3D indices of α angle and FHC were significantly lower anteriorly than posteriorly: αAnt = 58.2° (SD 6.1°), αPost = 63.8° (SD 6.3°) (p < 0.001), FHCAnt = 43.0 (SD 7.4), and FHCPost = 55.4° (SD 11.2°) (p < 0.001). Acetabular rounding measured byOCR indices was significantly greater in the anterior section of the hip (p < 0.001). We used 3DUS to show that hip shape and normal growth pattern vary significantly between anterior and posterior regions, by magnitudes similar to age-related changes. This highlights the need for careful selection of the Graf plane during 2D ultrasound examination. Whole-joint evaluation by obtaining either 3DUS or manual 'sweep' video images provides more comprehensive DDH assessment.Cite this article: Bone Jt Open2022;3(11):913-923.

Artificial intelligence-generated hip radiological measurements are fast and adequate for reliable assessment of hip dysplasia : an external validation study.

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. 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. 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. 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 Open2022;3(11):877-884.

Minimally Invasive Radiographic Evaluation of the Dysplastic Hip Joint Configuration in Terms of Surgical Treatment with Hip Preservation by PAO.

Residual developmental dysplasia of hip (RDDH) is a factor of early osteoarthritis of the hip. The main problems are pain and instability of the hip joint due to inadequate coverage of the femoral head by the acetabulum. The purpose of this study was to radiologically evaluate RDDH after Bernese periacetabular osteotomy (PAO) and to compare RDDH to healthy hips. The radiological parameters of RDDH treated by PAO were retrospectively evaluated. Digital AP pelvic radiographs were taken, including parameters of central edge angle and femoral head coverage, medialization, distalization, and ilio-ischial angle. Clinical assessment is based on the VAS scale. The study group consisted of patients with RDDH, and the control group consisted of patients without RDDH. After PAO radiological parameters decreased: medialization by 2.68mm, distalization by 3.65mm, and ilio-ischial angle by 2.62°. However, there was an increase in the parameters: CEA by 17.61° and FHC by 16.46%. There was a mean 3 point decrease in pain on the VAS scale. There was also a statistically significant radiological difference in the structure of dysplastic hip joints before surgery and healthy hip joints of the control group. Radiological studies confirmed the effectiveness of the PAO method in the treatment of RDDH. Based on all radiological parameters, differences between healthy and dysplastic hip joints were demonstrated. We believe that a thorough understanding of the values of radiological parameters used to describe dysplastic hip joints will allow us to improve the imaging diagnosis of this condition.

Morphometric study of acetabular depth and coverage and their clinical importance

To measure acetabular parameters and to compare parameters of acetabulum between men and women, and right and left sides. The study was conducted in PNS Shifa Hospital, Karachi from January to June 2021. Anteroposterior radiographs of both hips of 70 adults aged 20-70 years were included. The study consisted of 35 men and an equal number of women. We measured acetabular depth, femoral head coverage, acetabular inclination and acetabular depth and width. The acetabular depth was measured using Wiberg's central edge (CE) angle and Sharp angle techniques. Femoral head coverage was determined using measurements between medial edge of hip joint space, lateral edge of acetabulum and femoral head. To determine acetabular inclination, Tönnis angle was measured. Acetabular depth & width ratio (ADR) was evaluated by dividing acetabular width by depth, and multiplying by 100. There was significant increase in Sharp angle and Tonnis angle in females on the left side as compared to males. Wiberg's central edge angle and acetabular width to depth ratio showed insignificant increase in males as compared to females, whereas values of femoral head coverage were insignificantly more in women. The acetabular parameters were insignificantly different in gender and between right and left sides, although mean values were within normal range. The larger ADR ratio in men was most likely due to increased body weight in them as compared to women.

Reliability of the computed tomography criteria after closed reduction of developmental dislocation of the hip

BACKGROUND: Developmental dislocation of the hip includes femoral head subluxation or dislocation and/or acetabular dysplasia. Closed reduction of the hip should be performed under general anesthesia. Appropriate performance and interpretation of closed reduction are difficult and require experience. The role of computed tomography (CT) in different aspects of treatment of developmental hip dysplasia is well established. It was an accurate way to assess the adequacy of reduction of dislocated hips for patients in spica casts.&#x0D; AIM: This study aimed to assess the role of CT in the evaluation of closed reduction of developmental hip dislocation in infants and children immobilized in spica casts.&#x0D; MATERIALS AND METHODS: This study included 16 patients with 20 involved hips who presented with developmental hip dysplasia. The youngest patient was 12 months old, and the oldest was 24 months old, with a mean age of 19.62 4.27 months. There were 15 girls (93.75%) and one boy (6.25%). There were four patients with bilateral hip involvement (25%), and the right side was involved in five hips (31.25%), whereas the left side was affected in 7 (43.75%) hips.&#x0D; RESULTS: Closed reduction was performed in 20 hips, and according to the post-reduction CT evaluation, the final results were satisfactory in 16 (80%) hips and unsatisfactory in 4 (20%) hips. On the coronal CT cuts, the modified Shentons line gave a sensitivity of 75%, specificity of 81.25%, and accuracy of 80%. Second, the calculation of femoral head coverage on coronal CT cuts showed the highest sensitivity of 100%, specificity of 50%, and accuracy of 60%. Lastly, the posterior neck line identified on the axial CT cuts gave a sensitivity of 75%, specificity of 87%, and accuracy of 85%. On comparing and evaluating the three methods, the method that gave the best level of reliability for the adequacy of the reduction was the posterior neckline (82.23 %), followed by modified Shentons line (78.75%), and finally femoral head coverage (70%).&#x0D; CONCLUSIONS: The posterior neck line is the preferred method to confirm the adequacy of hip relocation on multi-slice post-reduction axial CT.

Testing of an Ultrasound-Limited Imaging Protocol for Pavlik harness Supervision (TULIPPS) in developmental dysplasia of the hip: a randomized controlled trial.

There is no consensus regarding optimum timing and frequency of ultrasound (US) for monitoring response to Pavlik harness (PH) treatment in developmental dysplasia of the hip (DDH). The purpose of our study was to determine if a limited-frequency hip US assessment had an adverse effect on treatment outcomes compared to traditional comprehensive US monitoring. This study was a single-centre noninferiority randomized controlled trial. Infants aged under six months whose hips were reduced and centred in the harness at initiation of treatment (stable dysplastic or subluxable), or initially decentred (subluxated or dislocated) but reduced and centred within four weeks of PH treatment, were randomized to our current standard US monitoring protocol (every clinic visit) or to a limited-frequency US protocol (US only at end of treatment). Groups were compared based on α angle and femoral head coverage at the end of PH treatment, acetabular indices, and International Hip Dysplasia Institute (IHDI) grade on one-year follow-up radiographs. Overall, 100 patients were included; 42 patients completed the standard protocol (SP) and 40 completed the limited protocol (LP). There was no significant difference in mean right α angle at the end of treatment (SP 70.0° (SD 3.2°) ; LP 68.7° (SD 2.9°); p = 0.033), nor on the left (SP 69.0° (SD 3.5°); LP 68.1° (SD 3.3°); p = 0.128). There was no significant difference in mean right acetabular index at follow-up (SP 23.1° (SD 4.3°); LP 22.0° (SD 4.1°); p = 0.129), nor on the left (SP 23.3° (SD 4.2°); LP 22.8° (SD 3.9°); p = 0.284). All hips had femoral head coverage of > 50% at end of treatment, and all were IHDI grade 1 at follow-up. In addition, the LP group underwent a 60% reduction in US use once stable. Our study supports reducing the frequency of US assessment during PH treatment of DDH once a hip is reduced and centred.Cite this article: Bone Joint J2022;104-B(9):1081-1088.

Active monitoring versus immediate abduction as treatment of stable developmental dysplasia of the hip: a systematic review of the literature

ObjectivesThis systematic review aims to compare the effects of active monitoring and abduction treatment on the Graf alpha angle, Acetabular Index (AI) and femoral head coverage in infants with stable...

The Method of Contact Area Assessment between the Femoral Head and Acetabulum in Children that Takes into Account Triradiate Cartilage

Relevance. Specific hip joint pathologies in children are characterized by insufficiency of the femoral head (FH) coverage by the acetabulum. This is reflected in the contact area reduction between the FH and acetabulum. In order to correct these acetabular deformities properly, the pediatric orthopedist must know in which direction develops a deficit of contact area between the FH and acetabulum and be able to assess the level of this deficit.&#x0D; Objective: to create an algorithm for the contact area assessment between the FH and acetabulum in children taking into account triradiate cartilage.&#x0D; Materials and Methods. Pelvic CT scans of a 6-year-old male child without hip joint pathologies were selected. A digital model of the pelvis was created using these CT scans. The pelvic model was transferred to a custom-made software, where the contact area between the FH and acetabulum was assessed in an indirect way.&#x0D; Results. The algorithm of the contact area assessment between the FH and acetabulum in children that takes into account triradiate cartilage was developed. Using the abovementioned algorithm, the contact area between the FH and acetabulum from both sides was assessed in a 6-year-old male child.&#x0D; Conclusions. Assessment of the normal contact area between the FH and acetabulum and in various pathological conditions in children will help pediatric orthopedists to understand better different hip joint pathologies and improve preoperative planning.

Greater hip abductor size in prearthritic patients with developmental dysplasia of the hip versusfemoroacetabular 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.

Femoral Head Coverage Assessment in Healthy Children Younger than 6 Years.

Introduction Developmental dysplasia of the hip (DDH) is one of the commonest hip joint pathologies in children; to treat it properly, hip surgeons should know the normal femoral head (FH) coverage by the acetabulum. This paper aims to assess the femoral head coverage in healthy children younger than 6 years. Methods 270 hip joint CT scans were selected, and digital pelvic models were created according to these scans. FH coverage by the five acetabular regions was assessed according to patient's age and sex. Results Normal reference values of FH coverage by different acetabular regions were obtained. It was found that the growth process of different acetabular regions occurs nonlinearly with the periods of acceleration. Anterior and superior-anterior acetabular regions grow more intensively in boys up to 3 years old and between 4 and 5 years old both in boys and girls; superior-posterior, posterior-superior, and posterior-inferior acetabular regions grow more intensively in boys and girls up to 3 years old and between 4 and 5 years old (p ≤ 0.005). The following sex differences in FH coverage by the acetabulum were found: more superior-anterior FH coverage was found in boys and posterior FH coverage in girls (p ≤ 0.005).

Comparison of Acetabular Measurements Between 2 Validated Software Programs Used in Hip Preservation Surgery

Background: Validated software tools (Clinical Graphics [CG] and Hip2Norm) permit measurement of the percentage of femoral head coverage (%FHC), which aids in morphological classification and prediction of outcome after hip preservation surgery. Purpose: (1) To assess whether acetabular parameter measurements determined from 2 commonly used software systems are comparable. (2) To determine which parameters influence the correlation or differences between software outputs and measurements. Study Design: Cohort study (diagnosis); Level of evidence, 2. Methods: The study included 69 patients (90 hips) who underwent periacetabular osteotomy and had comprehensive preoperative imaging available. Lateral center-edge angle (LCEA), acetabular index (AI), and %FHC were determined using 3-dimensional computed tomography (CT) measurements by CG and Hip2Norm software. Images of 18 pelvises were segmented to determine spinopelvic parameters and subtended acetabular angles. Between-group measurements were compared using correlation coefficients and Bland-Altman analyses. The difference in the outputs of the 2 programs was defined as delta (Δ). Radiographic parameters were tested to assess whether they were responsible for differences in %FHC between software programs. Results: Strong correlations between LCEA (ρ = 0.862) and AI (ρ = 0.825) measurements were seen between the Hip2Norm and CG programs. However, weak correlation was seen in the estimate of %FHC (ρ = 0.358), with the presence of a systematic error. Hip2Norm consistently produced lower anterior, posterior, and total %FHC values than CG. The %FHC determined by CG, but not Hip2Norm, correlated with acetabular subtended angles (P < .05). Pelvic tilt measured on CT did not correlate with pelvic tilt estimated by Hip2Norm (P = .56), and ΔPelvicTilt strongly correlated with the difference in %FHC by the 2 software programs (ρ = 0.63; P = .005), pelvic incidence (ρ = 0.73; P < .001), and pelvic tilt (ρ = −0.91; P < .001) as per CT. Conclusion: The correlation of %FHC between Hip2Norm and CG was weak (ρ = 0.358). The difference in measurements of %FHC correlated with ΔPelvicTilt. The %FHC determined by CG strongly correlated with the segmented acetabular subtended angles and thus more likely reflected true values. Hip preservation surgeons should be aware of these measurement differences because %FHC is important in the diagnosis and prognosis of acetabular dysplasia.