Abnormal Hip Research Articles

Validity and Reliability of the Thai Version of the Modified Harris Hip Score for Patients With Hip Abnormalities

The modified Harris Hip Score (mHHS) is one of the more commonly used patient-reported outcome measures to evaluate and monitor treatment in patients with hip abnormalities and has been translated into several languages. To develop a Thai version of the mHHS (TH-mHHS) and evaluate the validity and reliability of the measure. Cohort study (diagnosis); Level of evidence, 3. The TH-mHHS was developed using the forward-backward translation method. Patients who presented with hip pain during the first clinic visit completed the Thai version of questionnaires including the mHHS, 36-item Short Form Health Survey (TH-SF36), and Hip disability and Osteoarthritis Outcome Score (TH-HOOS). The validity between the measures was tested using the Spearman correlation coefficient. The test-retest reliability of the TH-mHHS was assessed using the intraclass correlation coefficient, and internal consistency was assessed using the Cronbach alpha. A total of 64 patients were enrolled who had a mean age of 52.8 ± 16.6 years (range, 17-80 years). There were 64% female and 36% male participants. The TH-mHHS showed a moderate correlation with all subscales of the TH-HOOS and the total TH-HOOS (r = 0.50-0.65; P < .01) and a high correlation with the physical functioning subscale and physical component summary of the TH-SF36 (r = 0.73 and 0.75, respectively; P < .01). The test-retest reliability was excellent, with an intraclass correlation coefficient of 0.95 (95% CI, 0.92-0.97; P < .001). The internal consistency was acceptable, with a Cronbach alpha of .71. No floor or ceiling effects were observed. The TH-mHHS showed a moderate to high correlation with the TH-SF36 and TH-HOOS, excellent test-retest reliability, and acceptable internal consistency. This measure can be effectively used for evaluating Thai patients with hip disorders, especially an older and arthritic population.

Combined Borderline Acetabular Dysplasia and Increased Femoral Anteversion Is Associated With Worse Outcomes in Female Patients Undergoing Hip Arthroscopy for Femoroacetabular Impingement

To determine the relationship of increased femoral anteversion and borderline acetabular dysplasia on the outcomes of hip arthroscopy for femoroacetabular impingement (FAI) in a female cohort of patients. This is a retrospective study of female patients undergoing hip arthroscopy for FAI. All patients had preoperative radiographs and computed tomography scans from which lateral center edge angle (LCEA) and femoral anteversion were measured. Patient outcome was quantified by preoperative and post-operative international hip outcome tool(iHOT)-12. All patients had follow-up at two to four years postoperatively. Published values for minimum clinically important difference(MCID), substantial clinical benefit(SCB), patient acceptable symptomatic state(PASS), and a normal or abnormal hip were used to determine outcome as well as the final score and delta of the iHOT12. There were 243 female patients included in the cohort (83% follow-up) that had iHOT12 scores at two-to-four-year follow-up (Mean 36.9 months). Females with combined LCEA≤25 degrees and Femoral anteversion over 20 degrees had lower Final IHOT12(p=0.001) and Delta iHOT12(p=0.010) and were less likely to achieve a normal hip(p=0.013), MCID(p=0.018), SCB(p<0.001), or PASS(p<0.001) and more likely to have an abnormal hip(p=0.002). In addition, patients with an LCEA≤25 degrees and normal femoral version were less likely to achieve a normal hip(p=0.013), SCB(p<0.001) and PASS(p<0.001) compared to those with normal acetabular coverage (all p<0.05). There was no difference in these outcome measures between the groups with an LCEA over 25 degrees with or without increased femoral version. Female patients with femoral anteversion over 20 degrees and borderline acetabular dysplasia did poorly after hip arthroscopy. However, those with increased femoral anteversion and normal acetabular coverage had outcomes similar to control hips. Level 4 case series.

Impact of the coronavirus disease 2019 pandemic on ultrasound screening of developmental dysplasia of the hip and follow-up imaging: a report from southeastern Turkey.

To investigate the effect of coronavirus disease 2019 restrictions on ultrasound (US) screening of developmental dysplasia of the hip (DDH) in a children's hospital. The records of US screening of DDH were retrospectively evaluated in the pandemic period (April 2020 to July 2021) and the pre-pandemic period (January 2019 to February 2020). The monthly US number, sex, radiologist number, and age at the initial examination were recorded. A total of 6107 US scans were performed during the pre-pandemic period, which significantly decreased to 3340 during the pandemic. The number of monthly US scans performed did not change between the pre-pandemic (142.7/month) and pandemic (128.2/month) periods. The number of delayed examinations in the total population did not significantly change between the two periods. However, the number of delayed examinations in patients with abnormal hips was significantly increased during the pandemic compared with that in the pre-pandemic period. Coronavirus disease 2019 restrictions decreased the US screening rate of DDH by almost half, but the number of US scans performed by each radiologist was unchanged. The compliance with follow-up recommendations was reduced by half, which may lead to an increase in the incidence of delayed and untreated DDH cases.

Radiological screening for DDH among risky infants in Abha Maternity &amp; Children Hospital from 2019-2021

Background: Developmental Dysplasia of the Hip (DDH) is the most common musculoskeletal condition diagnosed in neonates. Different timings and approaches to screening for DDH are used in the orthopedic community. Objectives: To provide evidence that DDH can be screened using sonarograph at the age of 2 months to decrease the risk of misdiagnosed DDH and determine the most common method of treatment regarding the radiological screening the infants underwent. Methods: This is a retrospective observational study that targeted all infants at risk of DDH who were born between 01-01-2019 to 31-12-2020 at Abha Maternity and Children Hospital (AMCH), Abha, Saudi Arabia. Included in the study were newborns who underwent radiological screening for hip with known risk factors for DDH. Demographic and clinical data were collected from the hospital electronic system. These data included subjects' age and sex, documented ultrasonography screening, documented X-ray diagnosis of DDH, and type of treatment. Results: A total of 201 infants (101 female, 100 male) aged from one day to six months (mean age 51.46 days, standard deviation 19.21 days) were included in the study. Ultrasonography screening revealed 40 subjects (19.9%) with positive DDH findings. X-rays done at age 4 to 6 months confirmed 26 (12.9%) DDH cases. Ultrasonography correctly detected 24 (11.9%) and excluded 159 (79.1) patients with DDH. However, two cases (1.0%) were not detected by ultrasonography and were later detected by X-ray, and 16 cases (8.0%) were falsely detected as positive DDH. Twenty-five subjects (12.4%) were treated conservatively, and one subject (0.5%) was treated surgically. Twenty-four cases of DDH showed hip abnormalities on ultrasound, giving a sensitivity rate of 92%. On the other side, 159 subjects who did not have DDH were screened negative with ultrasound (specificity rate 91%). Conclusions: The present study reveals that early US screening for DDH has high sensitivity and specificity and was associated with a lower rate of invasive intervention. Further research is needed to confirm these findings and examine potential factors influencing the accuracy of US-based screening programs in Saudi Arabia. Keywords: DDH; Ultrasound; Radiological screening

Factors for selective ultrasound screening in newborns with developmental dysplasia of the hip (DDH).

Hip ultrasound screening for DDH provides better sensitivity compared to physical examination. Due to a lower prevalence and limited resources, selective hip ultrasound in newborns at risk could be considered a proper screening protocol in Thailand and Asian countries. This study was aimed to evaluate risk factors and define criteria for selective screening. A case-control study was conducted in 2020. All newborns with hip ultrasound screening were included. Cases were defined as newborns with abnormal hip ultrasounds, while controls were those with normal studies. Inter and intra-rater reliability were evaluated. All factors were analyzed using univariate and multivariate logistic regression. The model performance was tested by Hosmer-Lemeshow goodness of fit. Internal validity was performed by the split data method. Area under the receiver operating characteristic (ROC) curve was estimated. Ninety-five newborns (29 cases and 66 controls) were included. Eighty percent of cases and 58% of controls were female. The gestational age was 36.6 and 37.7 weeks in case and control, respectively. Female, breech presentation, positive Ortolani test, positive Barlow test, and limited hip abduction were significant factors with odds ratio of 2.82, 5.12, 34.21, 69.64, and 5.48, respectively. The final model included breech presentation, positive Ortolani test, and positive Barlow test. The model cut-off value 15.02 provided sensitivity (93.10%) and specificity were (80.30%). The area under the ROC curve was 0.9308. The split data remained significant internal validity for all factors with p-value < 0.05. Careful history taking and physical examination are essential to identify the risk factors for DDH. Newborns with breech presentation, positive Ortolani test and positive Barlow test should be screened by hip ultrasound.

GELİŞİMSEL KALÇA DİSPLAZİSİ TANISINDA DERİN ÖĞRENME YÖNTEMLERİYLE ULTRASON TARAMALARINDAN STANDART DÜZLEM TESPİTİ

The term developmental dysplasia of the hip (DDH) describes a range of hip abnormalities affecting newborns where the femoral head and acetabulum are in improper alignment or grow abnormally, or both. The ultrasonographic evaluation technique rely on the capability of the ultrasonographer to pick up the accurate frame used for exact calculations. In our study we developed a new computer aided system that determines the exact frame from real time 2D ultrasound images and calculates the accuracy rate for each result. The deep learning architectures recently used in literature were utilized for these processes. In addition, transfer learning was carried out to increase the performance of the system using pretrained networks (SqueezeNet, VGG16, VGG19, ResNet50 and ResNet101). One of the best methods of object detection, You Only Look Once (YOLO) model, was used with pre-trained networks to determine DDH location. As a result of the study, the performance of the deep neural network model proposed with the help of these pre-trained networks was evaluated. When the obtained results were compared with expert opinions, frames (standard planes) in 605 of 676 (89.05%) test images were correctly detected. The accuracy rates for the used pre-trained networks were obtained as SqueezeNet 0.79, VGG16 0.95, VGG19 0.96, ResNet50 0.88 and ResNet101 0.93.

125 Evaluation of Normal Reference Ranges for Ultrasound Measurements of the Hip Joint in Elderly Patients

Ultrasound can be used to evaluate for effusion of the hip joint, which may be useful in screening for septic arthritis or occult injury. The current reference range for this measurement is based on decades- old ultrasound machine technology and hip joint capsule size was used as a surrogate for presumed presence of hip effusion. Normal range is a hip joint capsule (measured from anterior femoral neck to posterior iliopsoas) is <7mm or a 1mm or less difference between sides). The primary objective of this study was to determine whether the current reference range for this measurement is accurate and is sufficiently specific for abnormal hip joint capsule size in the elderly population.

Is Hip Medial Ultrasound More Accurate Than Radiography for Determining the Status of Hip Reduction in Children Treated With a Spica Cast? A Retrospective Diagnostic Accuracy Study.

Is Hip Medial Ultrasound More Accurate Than Radiography for Determining the Status of Hip Reduction in Children Treated With a Spica Cast? A Retrospective Diagnostic Accuracy Study.

Evaluation of additional causes of hip pain in patients with femoroacetabular impingement syndrome.

Femoroacetabular impingement syndrome (FAIS) is an increasingly prevalent pathology in young and active patients, that has contributing factors from both abnormal hip morphology as well as abnormal hip motion. Disease progression can be detrimental to patient quality of life in the short term, from limitations on sport and activity, as well as the long term through early onset of hip arthritis. However, several concurrent or contributing pathologies may exist that exacerbate hip pain and are not addressed by arthroscopic intervention of cam and pincer morphologies. Lumbopelvic stiffness, for instance, places increased stress on the hip to achieve necessary flexion. Pathology at the pubic symphysis and sacroiliac joint may exist concurrently to FAIS through aberrant muscle forces. Additionally, both femoral and acetabular retro- or anteversion may contribute to impingement not associated with traditional cam/pincer lesions. Finally, microinstability of the hip from either osseous or capsuloligamentous pathology is increasingly being recognized as a source of hip pain. The present review investigates the pathophysiology and evaluation of alternate causes of hip pain in FAIS that must be evaluated to optimize patient outcomes.

Use of Limited Hip Abduction as a Predictor for Developmental Dysplasia of the Hip

Background: Developmental dysplasia of the hip (DDH) includes multiple abnormalities. Females are more susceptible for DDH. The clinical examination is used for diagnosis, but its sensitivity is generally low. Ultrasound (US) examination identifies DDH in infants younger than 6 months of age. Because of its accessibility and the lack of exposure to radiation, the clinical applications of US in the diagnosis of DDH have expanded, making it the gold standard test for DDH. Objective: This study aimed to measure sensitivity and specificity of limited hip abduction (LHA) as a screening test for the detection of DDH. Materials and Methods: A cross-sectional study including 60 infants were brought to the Al-Wasity Teaching Hospital, Baghdad and Al-Rusafa Health Directorate, Ministry of Health and Environment, Baghdad, Iraq, within the period from January 2020 to October 2020. They were referred by other physicians and clinics or their parents suspected that they have abnormal hip. We excluded infants with associated congenital abnormality such as arthrogryposis or spina bifida. The diagnosis was made by clinical and US examination. The clinical examination included identification of LHA. Data regarding age and gender were recorded and were statistically analyzed. Frequencies and means were used to express data, and the χ2 goodness of fit test and Student’s t-test were used as appropriate to detect significance of difference between frequencies and means. Results: The sensitivity and specificity of unilateral and bilateral LHA were 51.35%, 95.18% and 27.03%, 63.86%, respectively. Conclusion: Unilateral LHA was more sensitive and specific than bilateral.

Paper 22: PREDICTORS OF RE-OPERATION IN ADOLESENTS UNDERGOING HIP PRESERVATION SURGERY FOR FEMOROACETABULAR IMPINGEMENT

Objectives:Femoroacetabular Impingement(FAI) is a condition caused by repetitive motion of abnormal hip osseous anatomy that contributes to labral and chondral injury. An understanding of radiographic parameters associated with successful primary surgery has not been well established. The primary objective was to determine pre-operative radiographic parameters that predict reoperation for FAI and, secondarily, correlate radiographic measures and outcomes in these patients.Methods:A prospectively-collected institutional registry of adolescent patients (age <19 y.o.) who underwent surgery for FAI (arthroscopic/open) was reviewed. Standing AP pelvis X-rays were analyzed for alpha, lateral center edge(LCEA), Tönnis, and Sharp’s angles, and femoro-epiphyseal acetabular(FEAR) index. Patient-reported outcomes(PROs) [modified Harris Hip Score (mHHS), Hip Disability and Osteoarthritis Outcome Score(HOOS)] were analyzed. Mann-Whitney-U test was used to compare the radiographic measures of re-operation to non-reoperation patients and those who achieved MCID to those who did not. Radiographic indication of risk for re-operation was evaluated with receiver operating characteristic(ROC) analysis. Spearman’s correlation was calculated between radiographic measurements and PROs at 2-years post-op.Results:Eighty-seven patients underwent primary surgery (56 surgical dislocations vs 31 scopes) for FAI. The average age at time of primary operation was 16.27 years(73.6%Female). 10 underwent re-operation (11.5%) at an average of 20.6 months from primary surgery. No differences were found in demographics, activity, surgery type, labral disease, or alpha angle for re-operation vs. non-reoperation. The LCEA, FEAR Index, Sharps, and Tönnis angle were significantly different (p<0.05) (Table 1).ROC analysis indicated that LCEA<21 and FEAR index>-8.8 were predictors for increased risk of reoperation. Patients with LCEA<21°, 46% underwent a reoperation compared to those with LCEA>21° (6%). Patients with FEAR index<-8.8, 32% underwent a reoperation compared to patients>-8.8 (5%). Patients who achieved MCID (61.9%) had lower BMI, worse pre-operative PROs, and better post-operative PROs at 2-years. Alpha, Tönnis, and Sharp’s angles were positively correlated with 2+ year PROs, while LCEA was negatively correlated(p<0.05).Conclusions:In patients undergoing treatment for FAI, a reoperation was associated with radiographic signs of hip dysplasia, indicating that patients with a shallower acetabulum are at risk for a repeat operation. Surgeons can utilize these parameters to help in surgical decision making, better predict outcomes and to counsel patients the need for potential subsequent surgery.UPLOAD-https://planion-client-files.s3.amazonaws.com/AOSSM/blobs/10177e80-b6a8-458e-b216-840ad950f2a6/1/Tables.docx

Evaluating the association between pulmonary abnormalities and complications following pediatric hip dysplasia surgery.

Developmental dysplasia of the hip (DDH) encompasses a wide range of abnormal hip development and is a common condition in the pediatric population. Congenital pulmonary abnormalities are typically mild in the pediatric population but can be associated with severe comorbid conditions. The purpose of this study was to analyze the effect of structural pulmonary/airway abnormalities on the incidence of postoperative complications following surgical management of DDH. From 2012 to 2019, the National Surgical Quality Improvement Program-Pediatric database was utilized to identify pediatric patients undergoing surgical treatment for hip dysplasia. Patients were stratified into two groups: patients with a structural pulmonary/airway abnormality and patients without a pulmonary abnormality. Patient demographics, comorbidities, and postoperative complications were compared between the two cohorts with the use of various statistical analyses, including bivariate and multivariate analyses. Of the 10,853 patients who underwent surgical treatment for hip dysplasia, 10,157 patients (93.6%) did not have a structural pulmonary/airway abnormality whereas 696 (6.4%) had an airway abnormality. Following adjustment on multivariate analysis, patients with a structural pulmonary abnormality had an increased risk of cardiac arrest requiring cardiopulmonary resuscitation (OR 2.342; p = 0.045). The results indicated that patients with a structural pulmonary abnormality had an increased risk of cardiac arrest requiring cardiopulmonary resuscitation compared to those without a pulmonary abnormality. Ensuring appropriate preoperative evaluation with a multidisciplinary team and close monitoring postoperatively is important to prevent the risk of severe outcomes in this vulnerable patient population.

Predictors of Re-Operation in Adolesents Undergoing Hip Preservation Surgery for Femoroacetabular Impingement

Background:Femoroacetabular Impingement(FAI) is a condition caused by repetitive motion of abnormal hip osseous anatomy that contributes to labral and chondral injury. An understanding of radiographic parameters associated with successful primary surgery has not been well established.Hypothesis/Purpose:The primary objective was to determine pre-operative radiographic parameters that predict reoperation for FAI and, secondarily, correlate radiographic measures and outcomes in these patients.Methods:A prospectively-collected institutional registry of adolescent patients (age <19 y.o.) who underwent surgery for FAI (arthroscopic/open) was reviewed. Standing AP pelvis X-rays were analyzed for alpha, lateral center edge(LCEA), Tönnis, and Sharp’s angles, and femoro-epiphyseal acetabular(FEAR) index. Patient-reported outcomes(PROs) [modified Harris Hip Score (mHHS), Hip Disability and Osteoarthritis Outcome Score(HOOS)] were analyzed. Mann-Whitney-U test was used to compare the radiographic measures of re-operation to non-reoperation patients and those who achieved MCID to those who did not. Radiographic indication of risk for re-operation was evaluated with receiver operating characteristic(ROC) analysis. Spearman’s correlation was calculated between radiographic measurements and PROs at 2-years post-op.Results:Eighty-seven patients underwent primary surgery (56 surgical dislocations vs 31 scopes) for FAI. The average age at time of primary operation was 16.27 years(73.6%Female). 10 underwent re-operation (11.5%) at an average of 20.6 months from primary surgery. No differences were found in demographics, activity, surgery type, labral disease, or alpha angle for re-operation vs. non-reoperation. The LCEA, FEAR Index, Sharps, and Tönnis angle were significantly different (p<0.05) (Table 1).ROC analysis indicated that LCEA<21 and FEAR index>-8.8 were predictors for increased risk of reoperation. Patients with LCEA<21°, 46% underwent a reoperation compared to those with LCEA>21° (6%). Patients with FEAR index<-8.8, 32% underwent a reoperation compared to patients>-8.8 (5%).Patients who achieved MCID (61.9%) had lower BMI, worse pre-operative PROs, and better post-operative PROs at 2-years. Alpha, Tönnis, and Sharp’s angles were positively correlated with 2+ year PROs, while LCEA was negatively correlated(p<0.05).Conclusion:In patients undergoing treatment for FAI, a reoperation was associated with radiographic signs of hip dysplasia, indicating that patients with a shallower acetabulum are at risk for a repeat operation. Surgeons can utilize these parameters to help in surgical decision making, better predict outcomes and to counsel patients the need for potential subsequent surgery.Table 1.Radiographic measurements of preoperative AP pelvis X-rays and their association with reoperation

Multi-landmark environment analysis with reinforcement learning for pelvic abnormality detection and quantification.

Morphological abnormalities of the femoroacetabular (hip) joint are among the most common human musculoskeletal disorders and often develop asymptomatically at early easily treatable stages. In this paper, we propose an automated framework for landmark-based detection and quantification of hip abnormalities from magnetic resonance (MR) images. The framework relies on a novel idea of multi-landmark environment analysis with reinforcement learning. In particular, we merge the concepts of the graphical lasso and Morris sensitivity analysis with deep neural networks to quantitatively estimate the contribution of individual landmark and landmark subgroup locations to the other landmark locations. Convolutional neural networks for image segmentation are utilized to propose the initial landmark locations, and landmark detection is then formulated as a reinforcement learning (RL) problem, where each landmark-agent can adjust its position by observing the local MR image neighborhood and the locations of the most-contributive landmarks. The framework was validated on T1-, T2- and proton density-weighted MR images of 260 patients with the aim to measure the lateral center-edge angle (LCEA), femoral neck-shaft angle (NSA), and the anterior and posterior acetabular sector angles (AASA and PASA) of the hip, and derive the quantitative abnormality metrics from these angles. The framework was successfully tested using the UNet and feature pyramid network (FPN) segmentation architectures for landmark proposal generation, and the deep Q-network (DeepQN), deep deterministic policy gradient (DDPG), twin delayed deep deterministic policy gradient (TD3), and actor-critic policy gradient (A2C) RL networks for landmark position optimization. The resulting overall landmark detection error of 1.5 mm and angle measurement error of 1.4° indicates a superior performance in comparison to existing methods. Moreover, the automatically estimated abnormality labels were in 95% agreement with those generated by an expert radiologist.

Hip physical examination extension loss and radiographic osseous findings in patients with low back pain and nonarthritic hips

The association between hip and spine abnormalities is frequent, and limitation in hip extension has been linked with low back pain. The purpose of this study was to assess the radiographic osseous findings in nonarthritic hips of patients with hip pain, low back pain, and limited hip extension. Ninety patients (92 hips) were included in this study. Hip extension was tested in the contralateral decubitus position with the hip in neutral abduction/adduction and neutral rotation. In sequence, hip extension was tested by adding passive abduction, followed by internal/external rotation of the hip. A hip extension limitation was defined as less than zero degrees of extension. Imaging studies were assessed for the following osseous morphologies: decreased ischiofemoral space (≤17 mm), increased femoral torsion (≥30°), decreased femoral torsion (≤5°), and posterior acetabular overcoverage. Fifty-seven out of 92 hips (62%) had at least one osseous imaging finding for limitation in hip extension: decreased ischiofemoral space (38/92, 41%), increased femoral torsion (5/92, 5%), decreased femoral torsion (24/92, 26%), and posterior acetabular overcoverage (21/92, 23%). Decreased ischiofemoral space, femoral torsional abnormalities, and/or posterior acetabular wall overcoverage are observed in imaging studies of most individuals with limitation of hip extension and low back pain.

Examination of the Newborn: The Key Skills 3. The Hips

Midwives are increasingly performing the newborn and infant physical examination (NIPE), particularly now the new Nursing and Midwifery Council (NMC) education proficiencies are inclusive of the systematic examination of the newborn infant.1 This article, the third in the series, considers the importance of the examination of the hips in this screening process. The significance of history taking, knowledge of risk factors and the hip examination are explored. The necessity for early detection and treatment of hip abnormalities, along with referral pathways that Public Health England requires, are highlighted. The impact of late detection of developmental dysplasia of the hip on the lives of families and children are also considered.

Association of Radiographic Markers of Hip Instability and Worse Outcomes 2 to 4 Years After Hip Arthroscopy for Femoroacetabular Impingement in Female Patients

Background: Reported outcomes of patients undergoing hip arthroscopy for femoroacetabular impingement (FAI) with underlying borderline acetabular dysplasia are mixed. This may in part be the result of mixed-sex reporting. Purpose: To determine the effect of radiographic measures of acetabular dysplasia and hip instability on outcomes of female patients undergoing hip arthroscopy for FAI. Study Design: Case-control study; Level of evidence, 3. Methods: This was a retrospective study of female patients undergoing arthroscopic surgery for FAI. All patients had preoperative radiographs including a standing anteroposterior pelvic view on which lateral center-edge angle (LCEA), anterior wall index (AWI), posterior wall index (PWI), and femoroepiphyseal acetabular roof (FEAR) index were measured. Patient outcomes were quantified by preoperative and postoperative 12-Item International Hip Outcome Tool (iHOT-12) scores. All patients had follow-up at 2 to 4 years postoperatively. Published values for minimal clinically important difference (MCID), substantial clinical benefit (SCB), Patient Acceptable Symptom State (PASS), and a normal (iHOT-12 > 86 points) or abnormal (iHOT-12 < 56 points) hip were used to determine outcome, as well as the final iHOT-12 score and iHOT-12 preoperative to postoperative difference. Results: The cohort consisted of 249 female patients (83% follow-up) with iHOT-12 scores at 2 to 4 years after surgery (mean, 34.6 months). Female patients with combined LCEA ≤25° and AWI <0.35 had lower final iHOT-12 score and iHOT-12 difference and were less likely to meet MCID, SCB, and PASS and have a normal hip and were more likely to have an abnormal hip as determined by iHOT-12 cutoffs when compared with those patients who had an LCEA >25° and an AWI ≥0.35 (all P < .05). There was no effect of PWI on outcomes. Similarly, female patients with combined LCEA ≤25° and a laterally oriented (positive) FEAR index were less likely to meet MCID, SCB, and PASS and have a normal hip and were more likely to have an abnormal hip compared with those patients who had an LCEA >25° and a negative (medial) FEAR index (all P < .05). In multivariate regression, an LCEA between 18° and 25° was an independent predictor of worse outcomes. Conclusion: An LCEA of 18° to 25°, in combination with an AWI of <0.35 or a laterally opening FEAR index, was predictive of worse outcomes in female patients undergoing hip arthroscopy for FAI.

A Preliminary Cadaveric MRI Study of Fetal Hip Development.

PurposeThe earlier the detection of the hip joint is discovered, the better the final result. The purpose of this study aimed to investigate the fetal hip development using magnetic resonance imaging (MRI), so as to alert clinicians to possible abnormal development during intrauterine life.MethodMeasurements of 34 cadaver fetuses (68 hips) were obtained regarding acetabular width and depth, anterior bony acetabular index (ABAI), anterior cartilaginous acetabular index (ACAI), posterior bony acetabular index (PBAI), and posterior cartilaginous acetabular index (PCAI). The standard values of each acetabular measurement index were obtained, and the gestational age-measurement index change trend chart was drawn to comprehensively analyze the normal development law of the fetal hip joint.ResultsWith the development of fetuses, the width and depth of acetabular increase linearly, and the slope of acetabular width was larger than that of depth. In addition, two change points during the 24th and 34th weeks of gestation were detected with regard to width. ABAI and PBAI also decreased. ABAI demonstrated an approximately linear trend, while PBAI shows a non-linear trend. During the 36th week, the change point in PBAI was observed. ACAI and PCAI exhibited slow increases, indicating a non-linear trend. During the 21st and 36th weeks of gestation, the change points regarding ACAI were observed. During the 22nd week of gestation, the change point for PCAI was observed.ConclusionPlots of the parameters obtained via MRI examinations of cadaver fetuses across gestational age comprehensively illustrated the fetal hip development. This developmental information about the hip joint has the potential to guide clinicians in the early detection of abnormal hip joint development during intrauterine life.

Validating the Cambridge Protocol: Reliability of Hip Muscle Strength Measurements Using a Motorized Dynamometer and Electromyography.

Muscle weakness is common after injury in athletes and in the presence of hip pathology. It will cause abnormal hip biomechanics and can predict future injury. However, objective measurement of hip muscle strength is difficult to perform accurately and reliably. Therefore, it is challenging to determine when an athlete has returned to preinjury levels of strength. In addition, there is currently no standardized method of obtaining measurements, which prevents the data being compared or shared between research centers. The purpose of this study is to comprehensively assess the inter- and intraobserver reliability of our standardized muscle strength measurement protocol. Descriptive laboratory study. Level 3, inception cohort study. A total of 16 healthy male volunteers (age = 28.3 ± 7.9 years) were recruited. Those with a previous history of hip injuries or disorders were excluded. These volunteers underwent strength testing according to the Cambridge Protocol on 4 separate occasions, performed by 2 independent assessors. Maximal voluntary contractions, fatigue torque fluctuations, and electromyography measurements were recorded. Intra- and interobserver reliability was assessed using intraclass correlation coefficient (ICC). Good-to-excellent correlation was seen for both intra- and interobserver reliability across almost all hip movements for maximal contractions: ICC ranged 0.78 to 0.93 and 0.78 to 0.96, respectively. The standard error of the mean for all hip movements was also extremely low at 2% to 3%. The Cambridge Protocol is a highly reliable method for objective measurement of hip muscle strength. We recommend future studies use this protocol, or the principles underpinning it, to enable data sharing and comparison across different studies. This is a description and analysis of hip muscle strength measurement. If widely used, it will allow for accurate and objective strength assessment and closer monitoring of hip injuries and pathology.

Effect of Patient Positioning on Measurement of the Anterior Center-Edge Angle on False-Profile Radiographs and Its 3-Dimensional Mapping to the Acetabular Rim.

Background:The anterior center-edge angle (ACEA) is used to quantify anterior coverage of the femoral head by the acetabulum. However, its measurement has not been evaluated in a manner consistent with routine use, and the precise 3-dimensional (3D) anatomic location where it measures coverage is not known.Purpose:To determine the effect of patient positioning on ACEA measurement reliability, magnitude, and 3D location.Study Design:Descriptive laboratory study.Methods:Included were 18 adults; 7 participants had cam morphology and femoroacetabular impingement syndrome, and 11 participants had no radiographic evidence of hip abnormalities and no history of hip pain or injuries. Ultimately, 3D femur and pelvis models were generated from computed tomography images. Radiographs were generated with the models in different degrees of pelvic rotation, tilt, and obliquity relative to the standard false-profile view. The ACEA was measured by 2 raters by selecting the location of the bone edge on each radiograph. Selections were projected onto the pelvis model and expressed as a clockface location on the acetabular rim. The clockface was mirrored on left hips to allow a direct comparison of locations between hips. Interrater and intrarater reliability were quantified via the intraclass correlation coefficient (ICC). The effect of position on ACEA measurements and clockface locations was determined via linear regression.Results:Intrarater and interrater reliability were excellent (ICC ≥0.97 for all). For every degree increase in rotation, tilt, and obliquity, the ACEA changed by +0.53°, +0.93°, and –0.04°, respectively. The mean clockface location (hour:minute:second) in the false-profile view was 2:09:32 ± 0:12:00 and changed by +0:02:08, –0:00:35, and –0:00:05 for every degree increase in rotation, tilt, and obliquity, respectively.Conclusion:ACEA measurements were reliable even with differences in patient positioning. Rotation and tilt were associated with notable changes in ACEA measurements. ACEA bone edge measurements mapped to the anterosuperior acetabular rim, typically in proximity to the anterior inferior iliac spine. Mapped location was most sensitive to rotation.Clinical Relevance:Pelvic rotation and tilt affected ACEA measurements, which could alter the clinical classification and treatment of borderline abnormalities. Rotation in particular must be well controlled during patient imaging to preserve measurement reliability and accuracy and to describe coverage from the intended 3D rim location.