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

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

Incidence of Nerve Palsies During Pavlik Harness Treatment for Developmental Dysplasia of the Hip: A Retrospective Cohort Study.

BACKGROUND: The Pavlik harness has been used for approximately a century to treat developmental dysplasia of the hip (DDH). Femoral nerve palsy is a documented complication of Pavlik harness use, with an incidence ranging from 2.5% to 11.2%. Rare reports of brachial plexus palsy have also been documented. The primary purpose of the current study was to evaluate the incidence of various nerve palsies in patients undergoing Pavlik harness treatment for DDH. Secondary aims were to identify patient demographic or hip characteristics associated with nerve palsy. METHODS: We performed a retrospective review of patients diagnosed with DDH and treated with a Pavlik harness from February 1, 2016, to April 1, 2023, at a single tertiary care orthopaedic hospital. Hip laterality, use of a subsequent rigid abduction orthosis, birth order, breech positioning, weight, and family history were collected. The median (and interquartile range [IQR]) or mean (and standard deviation [SD]) were reported for all continuous variables. Independent 2-sample t tests and Mann-Whitney U tests were conducted to identify associations between the variables collected at the initiation of Pavlik harness treatment and the occurrence of nerve palsy. RESULTS: Three hundred and fifty-one patients (547 hips) were included. Twenty-two cases of femoral nerve palsy (4% of all treated hips), 1 case of inferior gluteal nerve palsy (0.18%), and 2 cases of brachial plexus palsy (0.37%) were diagnosed. Patients with nerve palsy had more severe DDH as measured by the Graf classification (p < 0.001) and more severe DDH as measured on physical examination via the Barlow and Ortolani maneuvers (p = 0.003). CONCLUSIONS: Nerve palsies were associated with more severe DDH at the initiation of Pavlik harness use. Upper and lower-extremity neurological status should be scrutinized at initiation and throughout treatment to assess for nerve palsies. The potential for femoral, gluteal, and brachial plexus palsies should be included in the discussion of risks at the beginning of treatment. Families may be reassured that nerve palsies associated with Pavlik harness can be expected to resolve with a short break from treatment. LEVEL OF EVIDENCE: Therapeutic Level III. See Instructions for Authors for a complete description of levels of evidence.

Retroverting Periacetabular Osteotomy for Symptomatic Acetabular Anteversion.

BACKGROUND: Acetabular dysplasia has traditionally been defined using the lateral center edge angle and treated with periacetabular osteotomy (PAO). However, the recently described Ottawa classification further quantifies dysplasia in 3-dimensional terms, categorizing Ottawa A as dysplasia due to isolated, excessive acetabular anteversion or anterior acetabular under-coverage. We sought to determine if patients who have Ottawa A dysplasia can expect similar outcomes when undergoing a PAO compared to a traditional dysplasia cohort. METHODS: Patients who had undergone PAO with Ottawa A hip dysplasia were selected and compared to a control group of patients who had lateral acetabular undercoverage. The modified Harris Hip Score and International Hip Outcome Tool-33 were collected preoperatively and at various follow-up points for a final follow-up average of 2.3 years (range, 0.9 to 6.2). RESULTS: The 17 patients (21 hips) who had Ottawa A dysplasia were compared to a control cohort of 69 patients (88 hips). Both groups saw significant improvements in modified Harris Hip Score and International Hip Outcome Tool-33 at final follow-up, P < .001. There were no differences between groups in any of the outcome measures or rates of achieving minimal clinically important difference (MCID) or substantial clinical benefit. Rates of MCID ranged from 82.4 to 100%, and rates of achieving substantial clinical benefit ranged from 47.1 to 52.9%. CONCLUSIONS: In patients undergoing a PAO for Ottawa A hip dysplasia, a significant improvement in patient-reported outcomes can be expected with high rates of MCID achievement. This is not significantly different for patients undergoing PAO for more traditional dysplasia parameters.

Risk Factors for Suboptimal Outcome of FAI Surgery in the Adolescent Patient.

BACKGROUND: Surgical treatment for adolescent patients with femoroacetabular impingement (FAI) is increasing. The purpose of this study was to determine the clinical outcomes of FAI surgery in a multicenter cohort of adolescent patients and to identify predictors of suboptimal outcomes. METHODS: One hundred twenty-six adolescent hips (114 patients < 18 years of age) undergoing surgery for symptomatic FAI were studied from a larger multicenter cohort. The group included 74 (58.7%) female and 52 male hips (41.3%) with a mean age of 16.1 (range 11.3 to 17.8). Clinical outcomes included the modified Harris Hip Score (mHHS), Hip disability and Osteoarthritis Outcome Score (5 domains), and University of California Los Angeles activity score. Failure was defined as revision surgery or clinical failure (inability to reach minimally clinical important differences or patient acceptable symptoms state for the mHHS). Statistical analysis was used to identify factors significantly associated with failure. RESULTS: There was clinically important improvement in all patient-reported outcomes for the overall group, but an 18.3% failure rate. This included a revision rate of 8.7%. Females were significantly more likely than males to be classified as a failure (25.7 vs. 7.7%, P =0.01), in part because of lower preoperative mHHS (59.1 vs. 67.0, P < 0.001). Mild cam deformity (alpha angle <55 degrees) was present in 42.5% of female hips compared with 17.3% male hips. Higher alpha angles were inversely correlated with failure. Alpha angles >63 have a failure rate of 8.3%, between 55 and 63 degrees, 12.0% failure rate, and <55 degrees (mild cam) failure rate of 37.5%. Patients who participated in athletics had a 10.3% failure rate compared with nonathletes at 25.0% ( P =0.03, RR (relative risk) 2.4). CONCLUSIONS: Adolescent patients undergoing surgical treatment for FAI generally demonstrate significant improvement. However, female sex, mild cam deformities, and lack of sports participation are independently associated with higher failure rates. These factors should be considered in surgical decision-making and during patient counseling. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

The Impact of Age on Clinical Outcomes of Acetabular Microfracture During FAI Surgery.

BACKGROUND: Full-thickness acetabular cartilage lesions are common findings during primary surgical treatment of femoroacetabular impingement (FAI). PURPOSE: To evaluate clinical outcomes after acetabular microfracture performed during FAI surgery in a prospective, multicenter cohort. STUDY DESIGN: Cohort Study; Level of evidence, 3. METHODS: Patients with FAI who had failed nonoperative management were prospectively enrolled in a multicenter cohort. Preoperative and postoperative (mean follow-up, 4.3 years) patient-reported outcome measures were obtained with a follow-up rate of 81.6% (621/761 hips), including 54 patients who underwent acetabular microfracture. Patient characteristics, radiographic parameters, intraoperative disease severity, and operative procedures were analyzed. Propensity matching using linear regression was used to match 54 hips with microfracture to 162 control hips (1:3) to control for confounding variables. Subanalyses of hips ≤35 and >35 years of age with propensity matching were also performed. RESULTS: Patients who underwent acetabular microfracture were more likely to be male (81.8% vs 40.9%; P < .001), be older in age (35.0 vs 29.9 years; P = .001), have a higher body mass index (27.2 vs 25.0; P = .001), and have a greater alpha angle (69.6° vs 62.3°; P < .001) compared with the nonmicrofracture cohort (n = 533). After propensity matching to control for covariates, patients treated with microfracture displayed no differences in the modified Harris Hip Score or Hip Disability and Osteoarthritis Outcome Score (P = .22-.95) but were more likely to undergo total hip arthroplasty (THA) (13% [7/54] compared with 4% [6/162] in the control group; P = .002), and age >35 years was associated with conversion to THA after microfracture. Microfracture performed at or before 35 years of age portended good outcomes with no significant risk of conversion to THA at the most recent follow-up. CONCLUSION: Microfracture of acetabular cartilage defects appears to be safe and associated with reliably improved short- to mid-term results in younger patients; modified expectations should be realized when full-thickness chondral lesions are identified in patients >35 years of age.

Long-term Outcomes After Arthroscopic Treatment of Femoroacetabular Impingement for Patients With Borderline Dysplasia.

BACKGROUND: Outcomes after isolated hip arthroscopic surgery for patients with dysplasia have been unfavorable. Results have included iatrogenic instability and conversion to total hip arthroplasty at a young age. However, patients with borderline dysplasia (BD) have shown more favorable results at short- and medium-term follow-up. PURPOSE: To assess long-term outcomes after hip arthroscopic surgery for femoroacetabular impingement in patients with BD (lateral center-edge angle [LCEA] = 18°-25°) compared with a control group of patients without dysplasia (LCEA = 26°-40°). STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: We identified a group of 33 patients (38 hips) with BD who were treated for FAI between March 2009 and July 2012. An age- and sex-matched control group of 83 patients (96 hips) was also identified. Patient-reported outcome scores were collected preoperatively and subsequently at a mean of 9.6 years postoperatively. RESULTS: The mean LCEA and Tönnis angle were 22.42°± 2.02° and 6.27°± 3.23° in the BD group, respectively, and 31.71°± 3.52° and 2.42°± 3.02° in the control group, respectively (P < .001). At a mean follow-up of 9.6 years (range, 8.2-11.6 years), there was a significant improvement in all patient-reported outcome scores in both groups (P < .001). There were no significant differences between preoperative and postoperative scores or rates of achieving the minimal clinically important difference between the BD and control groups. Bilateral surgery was noted to be a risk factor for any revision during the follow-up period (P < .001). There were 2 hips (5.3%) that underwent revision surgery in the BD group and 10 hips (10.4%) in the control group; of these, 1 patient in the BD group underwent total hip arthroplasty, and 1 patient who had undergone bilateral surgery in the control group underwent bilateral hip resurfacing. CONCLUSION: Durable outcomes (>9 years) with low revision rates can be expected after hip arthroscopic surgery with an approach that involves labral preservation where possible and careful attention to capsular closure in patients with BD. The observed outcomes were similar to those of a femoroacetabular impingement group with normal coverage. These results highlight the importance of classifying patients into impingement or instability categories and tailoring treatment appropriately with arthroscopic surgery or periacetabular osteotomy, respectively.

The Effects of Arthroscopic Labral Repair on Patient-Reported Outcomes in the Setting of Periacetabular Osteotomy.

BACKGROUND: It is currently unknown whether the addition of arthroscopic labral repair in the setting of periacetabular osteotomy (PAO) provides any clinical benefit. PURPOSE/HYPOTHESIS: The purpose of this study was to compare outcomes of patients who underwent arthroscopic labral repair concomitantly with PAO versus patients who underwent PAO alone. We hypothesized that there would be no difference in patient-reported outcome measures (PROMs) between the cohorts. STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: Patients undergoing PAO from a single-center prospective hip preservation registry were eligible for this study if they completed pre- and postoperative PROMs (minimum, 1 year). PROMs were collected at 1 year, 2 years, and latest follow-up at 6.05 years for PAO group and 4.2 years for scope/PAO group. The study group consisted of 53 patients who underwent arthroscopic labral repair at the time of their PAO, and the comparison group consisted of 170 patients who underwent PAO alone. A subset of the PAO group who had radiologic evidence of a detached labral tear (n = 33) was also compared with the rest of the PAO-alone group. PROMs were compared at every time point for both groups as well as the subset of patients who underwent PAO alone despite a labral tear. RESULTS: The mean follow-up of all patients was 2 years (range, 1-6 years). Overall, 85.2% of the PAO group and 85.7% of the scope/PAO group met the minimal clinically important difference for either the modified Harris Hip Score (mHHS) or the International Hip Outcome Tool (iHOT-33) at the most recent follow-up. There was no difference in improvement between groups (mHHS, P = .670; iHOT-33, P = .944). Patients who had a radiologically diagnosed detached labral tear and underwent PAO alone had no difference in outcomes when compared with the rest of the PAO cohort (mHHS, P = .981; iHOT-33, P = .909). CONCLUSION: There was no significant benefit measured by PROMs at follow-up for concomitant arthroscopic labral repair in the setting of PAO.

Highly Cited Articles in Periacetabular Osteotomy Research.

Purpose: The aim of this study is to identify highly cited articles and examine trends and characteristics in research on periacetabular osteotomy. Materials and Methods: The 50 most highly cited articles on periacetabular osteotomy research were identified using Scopus. Data regarding article demographics and publication were collected from each article and an analysis was performed. Results: The mean citation count was 125±37. The article with the highest total citation count (796), five-year citation count (327), and five-year citation density (65/year) was reported by Reinhold Ganz. The five-year citation density showed strong correlation with total citation density (r=0.930, P<0.001). Reinhold Ganz, the most productive author, was listed on 13 articles in the cohort with 455 weighted citation points. Conclusion: This study provides a collection of articles examining periacetabular osteotomies and demonstrates that citation count can be regarded as an acceptable measure of the contemporary academic influence of an article.

Hip Morphology in Periacetabular Osteotomy (PAO) Patients Treated for Developmental Dysplasia of the Hip (DDH) as Infants Compared With Those Without Infant Treatment.

BACKGROUND: A subset of patients successfully treated for developmental dysplasia of the hip (DDH) as infants have symptomatic acetabular dysplasia at skeletal maturity leading to periacetabular osteotomy (PAO). The purpose of this study was to compare femoral and acetabular morphology in PAO patients with late acetabular dysplasia after previous treatment for DDH with PAO patients who do not have a history of DDH treatment. METHODS: A single surgeon's patients who underwent PAO between 2011 and 2021 were retrospectively reviewed. Patients previously treated for infantile DDH with a Pavlik harness, abduction brace, closed reduction and spica casting, or open reduction and spica casting were included. Patients with previous bony hip surgery were excluded. Preoperative radiographic measurements of each hip were recorded including lateral center edge angle, anterior center edge angle, and Femoro-Epiphyseal Acetabular Roof index. Computed tomography measurements included the coronal center edge angle, sagittal center edge angle, Tönnis angle, acetabular anteversion at 1, 2, and 3 o'clock, femoral neck-shaft angle, femoral version, and alpha angle. Control PAO cases without a history of DDH diagnosis or treatment were matched with the infantile DDH treatment group in a 2:1 ratio based on coronal center edge angle, age, and sex. RESULTS: There were 21 hips in 18 patients previously treated for infantile DDH (13 patients Pavlik harness, 3 abduction brace, 1 closed reduction, and 1 open reduction). The control PAO cohort was 42 hips in 42 patients who did not have previous DDH treatment. There was no statistically significant difference in any of the recorded measurements between patients previously treated for DDH and those without previous treatment including femoral version (P=0.494), anteversion at 1 o'clock (P=0.820), anteversion at 2 o'clock (P=0.584), anteversion at 3 o'clock (P=0.137), neck-shaft angle (P=0.612), lateral center edge angle (P=0.433), Femoro-Epiphyseal Acetabular Roof index (P=0.144), and alpha angle (P=0.156). CONCLUSIONS: Femoral and acetabular morphology is similar between PAO patients with persistent symptomatic acetabular dysplasia following DDH treatment and patients presenting after skeletal maturity with acetabular dysplasia and no previous history of DDH treatment. LEVEL OF EVIDENCE: Level III-case-control, prognostic study.

Interrater Reliability of the Prone Apprehension Relocation Test.

BACKGROUND: The Prone Apprehension Relocation Test (PART) augments existing radiographic measures and clinical provocative maneuvers in diagnosing hip instability. One measure of the potential clinical utility of the PART depends on the reproducibility of test results by evaluating providers including physicians, licensed athletic trainers, and physical therapists. PURPOSE: To determine the interrater reliability of the PART among health care providers. STUDY DESIGN: Cohort study (diagnosis); Level of evidence, 3. METHODS: We retrospectively identified patients in our institution's hip preservation registry who presented between September 2017 and June 2019 for evaluation of hip pain. Patients included in the study had the PART performed by a single physician as well as 1 of 12 physician extenders (a licensed athletic trainer or a physical therapist). The providers were blinded to the findings of the other examining professional. Interrater reliability was assessed using the Cohen κ (≥0.75 was considered excellent; between 0.75 and 0.40, moderate; and ≤0.40, poor). RESULTS: A total of 96 patients (190 hips) were included in this study (61 women and 35 men, average age 32 ± 12.1 years). A total of 23 hips had a positive PART from both examiners. Interrater reliability was excellent between health care professionals for the PART when evaluating the right hip (κ = 0.80), left hip (κ = 0.82), and when combining the results for left and right (κ = 0.81). A subanalysis of patients with a positive PART from both raters demonstrated that 19 of the 23 hips had a lateral center-edge angle >25°. CONCLUSION: Our study demonstrated excellent interrater reliability of the PART, supporting its use in the physical evaluation of painful hips.

Predicting the Risk of Subsequent Hip Surgery Before Primary Hip Arthroscopy for Femoroacetabular Impingement Syndrome: A Machine Learning Analysis of Preoperative Risk Factors in Hip Preservation.

BACKGROUND: The number of patients requiring reoperation has increased as the volume of hip arthroscopy for femoroacetabular impingement syndrome (FAIS) has increased. The factors most important in determining patients who are likely to require reoperation remain elusive. PURPOSE: To leverage machine learning to better characterize the complex relationship across various preoperative factors (patient characteristics, radiographic parameters, patient-reported outcome measures [PROMs]) for patients undergoing primary hip arthroscopy for FAIS to determine which features predict the need for future ipsilateral hip reoperation, namely, revision hip arthroscopy, total hip arthroplasty (THA), hip resurfacing arthroplasty (HRA), or periacetabular osteotomy (PAO). STUDY DESIGN: Cohort study; Level of evidence, 3. METHODS: A cohort of 3147 patients undergoing 3748 primary hip arthroscopy procedures were included from an institutional hip preservation registry. Preoperative computed tomography of the hip was obtained for each patient, from which the following parameters were calculated: the alpha angle; the coronal center-edge angle; the neck-shaft angle; the acetabular version angle at 1, 2, and 3 o'clock; and the femoral version angle. Preoperative PROMs included the modified Harris Hip Score (mHHS), the Hip Outcome Score (HOS)-Activities of Daily Living subscale (HOS-ADL) and the Sport Specific subscale, and the international Hip Outcome Tool (iHOT-33). Random forest models were created for revision hip arthroscopy, the THA, the HRA, and the PAO. Area under the curve (AUC) for the receiver operating characteristic curve and accuracy were calculated to evaluate each model. RESULTS: A total of 171 patients (4.6%) underwent subsequent hip surgery after primary hip arthroscopy for FAIS. The AUC and accuracy, respectively, were 0.77 (fair) and 76% for revision hip arthroscopy (mean, 26.4-month follow-up); 0.80 (good) and 81% for THA (mean, 32.5-month follow-up); 0.62 (poor) and 69% for HRA (mean, 45.4-month follow-up); and 0.76 (fair) and 74% for PAO (mean, 30.4-month follow-up). The most important factors in predicting reoperation after primary hip arthroscopy were higher body mass index (BMI) and lower preoperative HOS-ADL for revision hip arthroscopy, greater age and lower preoperative iHOT-33 for THA, increased BMI for HRA, and larger neck-shaft angle and lower preoperative mHHS for PAO. CONCLUSION: Despite the low failure rate of hip arthroscopy for FAIS, our study demonstrated that machine learning has the capability to identify key preoperative risk factors that may predict subsequent ipsilateral hip surgery before the index hip arthroscopy. Knowledge of these demographic, radiographic, and patient-reported outcome data may aid in preoperative counseling and expectation management to better optimize hip preservation.

Sex Differences in Clinical Outcomes Following Surgical Treatment of Femoroacetabular Impingement.

BACKGROUND: Sex-based differences in clinical outcomes following surgical treatment of femoroacetabular impingement remain largely uncharacterized; this prospective, multicenter study evaluated these differences both directly and adjusted for covariates. METHODS: Hips undergoing surgical treatment of symptomatic femoroacetabular impingement were prospectively enrolled in a multicenter cohort. Patient demographics, radiographic parameters, intraoperatively assessed disease severity, and history of surgical procedures, as well as patient-reported outcome measures, were collected preoperatively and at a mean follow-up of 4.3 years. A total of 621 (81.6%) of 761 enrolled hips met the minimum 1 year of follow-up and were included in the analysis; 56.7% of analyzed hips were female. Univariate and multivariable statistics were utilized to assess the direct and adjusted differences in outcomes, respectively. RESULTS: Male hips had greater body mass index and larger α angles. Female hips had significantly lower preoperative and postoperative scores across most patient-reported outcome measures, but also had greater improvement from preoperatively to postoperatively. The preoperative differences between sexes exceeded the threshold for the minimal clinically important difference of the modified Harris hip score (mHHS) and all Hip disability and Osteoarthritis Outcome Score (HOOS) domains except quality of life. Preoperative sex differences in mHHS, all HOOS domains, and Short Form-12 Health Survey physical function component score were greater than the postoperative differences. A greater proportion of female hips achieved the minimal clinically important difference for the mHHS, but male hips were more likely to meet the patient acceptable symptom state for this outcome. After adjusting for relevant covariates with use of multiple regression analysis, sex was not identified as an independent predictor of any outcome. Preoperative patient-reported outcome scores were a strong and highly significant predictor of all outcomes. CONCLUSIONS: Significant differences in clinical outcomes were observed between sexes in a large cohort of hips undergoing surgical treatment of femoroacetabular impingement. Despite female hips exhibiting lower baseline scores, sex was not an independent predictor of outcome or reoperation. LEVEL OF EVIDENCE: Prognostic Level II. See Instructions for Authors for a complete description of levels of evidence.

The use of image analysis software increases the accuracy of the periacetabular osteotomy fragment placement.

The purpose of this study was to report on the use of image analysis technology to enhance accuracy of intra-operative imaging and evaluation of periacetabular osteotomy (PAO) correction. This was a retrospective study reporting on the first 25 cases of PAO performed with the use of an image analysis tool. This technology was used intra-operatively to assess the position of the supine coronal image in comparison to pre-operative standing images using a ratio of pelvic tilt (PT). Intra-operative PT, Tönnis angle, lateral center-edge angle (LCEA) and anterior wall index were compared to post-operative images. Post-operative radiographic parameters in the study group were compared with a control group of PAO cases performed prior to the implementation of the new software. The image analysis software was able to obtain intra-operative supine imaging that was equivalent to pre-operative standing imaging. When comparing the PAOs performed with the use of the software versus those without, the study group trended toward being more likely within the surgeon's defined target range of radiographic values, which was statistically significant for LCEA. This tool can be used to assure the surgeon that the intra-operative image being used for surgical decision-making is representative of the functional radiograph. PAOs performed with the use of this technology showed enhanced accuracy of surgical correction for the parameters within our defined target ranges. This may increase the ability of the surgeon to place the acetabular fragment more precisely within his or her goal parameters for acetabular reorientation correction.

Adolescent hip dysplasia: what are the symptoms and how to diagnose it.

PURPOSE OF REVIEW: Adolescent and young adult hip dysplasia is a cause of hip pain which can lead to early hip osteoarthritis. This may result in early hip osteoarthrosis and possible total hip arthroplasty if dysplasia is not recognized and treated. Hip dysplasia in this population can be difficult to diagnose. It is important for primary care providers and pediatricians to recognize the symptoms, physical examination findings, and radiographic findings associated with adolescent hip dysplasia so that the patient can be referred to an orthopedist specializing in hip disorder. The current review includes the most up-to-date literature on the diagnosis of adolescent hip dysplasia. RECENT FINDINGS: Recent studies have shown that most patients presenting with symptomatic hip dysplasia present with insidious onset hip pain localized to either the groin or lateral aspect of the hip in a C-shape distribution around the inguinal crease. Patients most commonly see several different providers and have pain for a long period prior to accurate diagnosis. There are myriad radiographic measurements of hip dysplasia, many of which are described below that are helpful in initial diagnosis. SUMMARY: Adolescent and young adult hip dysplasia can be a cause of early, progressive hip osteoarthritis. Hip dysplasia is a term that represents a spectrum of disorder due to abnormal formation of the hip joint, resulting in an acetabulum that does not sufficiently cover the femoral head. The ability to recognize symptoms, physical examination findings, and radiographic evidence of adolescent hip dysplasia is critical so that the patient can be referred to the appropriate provider and receive timely treatment prior to the onset of degenerative hip disease. This article will focus mainly on the diagnosis of adolescent hip dysplasia. The standard for treatment of acetabular dysplasia in skeletally mature patients is the periacetabular osteotomy; however, nonoperative management and occasionally arthroscopic surgery can also be considered in cases of symptomatic borderline dysplasia.

Radiographic and clinical characteristics associated with a positive PART (Prone Apprehension Relocation Test): a new provocative exam to elicit hip instability.

Hip instability due to mild dysplasia can be a diagnostic challenge. The physical exam is an important adjunct to radiographic evaluation for the clinical diagnosis of hip instability. Herein, we describe a new maneuver to replicate hip instability pain, called the PART (Prone Apprehension Relocation Test). We retrospectively identified patients in our institution's hip preservation registry who presented for evaluation of hip pain. We divided patients into 'positive' or 'negative' PART and analyzed associated clinical and radiographic findings. Ninety patients (159 hips) were included, 83 female and 7 male, average age 27.3 ± 9.1 years. Thirty-four hips (21.4%) had a positive PART. There were no significant differences in hip range of motion, lateral center edge angle, or in acetabular depth. There was, however, a significant difference in acetabular version at 3 o'clock between the two test groups (18.5 ± 6.9° in negative, 21.2 ± 4.9° in positive, P = 0.045). There was no association between PART and previously described anterior apprehension testing. Historical methods of diagnosing hip dysplasia may not adequately identify patients with clinical hip instability. We describe a new provocative exam, the PART, which may be helpful in replicating hip instability symptoms in patients with anterior acetabular undercoverage. PART positive patients had significantly more acetabular anteversion at the 3 o'clock position, which is measured on computed tomography and is not visible on standard anteroposterior (AP) pelvis or false profile radiographs. We believe that the PART is a valuable supplement to clinical examination and radiographic measurements to identify patients with symptomatic hip instability.

Periacetabular Osteotomy as a Salvage Procedure: Early Outcomes in Patients Treated for Iatrogenic Hip Instability.

BACKGROUND: A periacetabular osteotomy (PAO) can reduce pain and improve quality of life in patients with hip dysplasia. While its utility for patients without traditional radiographic parameters for hip dysplasia has not been previously established, the PAO may help treat patients with hip instability that does not improve following single or multiple hip arthroscopic procedures, or when such procedures lead to hip instability. METHODS: A single-surgeon registry of patients at a single institution was queried to identify patients with a lateral center-edge angle (LCEA) of ≥24° and a Tönnis angle of <10° who underwent PAO because of hip pain and/or instability that failed treatment with hip arthroscopy. Descriptive summary statistics were reported on patient demographics, mean change in LCEA, and patient-reported outcome measures, including the modified Harris hip score (mHHS) and the International Hip Outcome Tool-33 (iHOT-33), at a minimum of 6 months of follow-up. RESULTS: Among 25 patients (mean age, 27.3 ± 6.9 years; 100% women), the mean LCEA increased from 27.2° (range, 24° to 37°) preoperatively to 39.0° ± 5.1° postoperatively (net increase, 11.8° ± 4.5°). Overall, the mean improvement in the mHHS was 11.5 ± 16.9 (preoperative, 59.4 ± 11.6; postoperative, 70.9 ± 20.6) and the mean improvement in the iHOT-33 was 23.8 ± 23.6 (preoperative, 32.2 ± 17.2; postoperative, 56.0 ± 30.0). Eighteen patients (72%) achieved a minimal clinically important improvement in mHHS (mean improvement, 17.4 ± 12.9) and iHOT-33 (mean improvement, 32.4 ± 19.1) scores. In comparison with 7 patients who did not show improvement, the 18 patients who showed improvement had significantly greater mean baseline patient-reported outcome scores. CONCLUSIONS: To our knowledge, these findings provide the first report on outcomes of PAO in patients with hip pain following arthroscopy who do not meet the traditional criteria for acetabular dysplasia. Early benefits in clinical outcomes suggest a novel surgical indication for PAO as a potential salvage option for selected patients; however, longer-term studies are needed. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Characterization of version in the dysplastic hip and the need for subsequent femoral derotational osteotomy after periacetabular osteotomy.

Hip dysplasia is a three-dimensional pathomechanical condition that is often more complex than the standard method of measuring lateral center edge angle (CEA) can quantify. Yet there is a paucity of literature examining the differences in version seen between dysplastic and non-dysplastic femoroacetabular impingement (FAI) hips, the relationship of acetabular and femoral version (FV) within dysplastic hips and the contribution of each of these factors to symptoms and outcomes of dysplasia treatment. We sought to describe the acetabular version (AcetV) and FV in dysplastic hips and quantify how these measurements compared with non-dysplastic FAI hips. We also sought to analyze the association of these factors with patient-reported outcomes (PROs) after periacetabular osteotomy (PAO) and determine the need for subsequent femoral derotational osteotomy after PAO. A total of 113 dysplastic patients who underwent PAO (92% female, mean age 24) were compared with 1332 (45% female, mean age 25) non-dysplastic FAI (CEA > 25°) patients. We found that dysplastic hips had a statistically higher AcetV and FV than non-dysplastic FAI hips. There was a very weak correlation between AcetV and FV in dysplastic hips, suggesting that patients with higher AcetV did not necessarily have higher FV. There was no association with AcetV or FV and patient outcomes in our very limited analysis of PROs after PAO, and only 5% of patients with excessive FV (>20°) required subsequent femoral derotational osteotomy, suggesting that in a majority of patients with hip dysplasia, FV may not impact the post-operative clinical course.

Clinical and Radiographic Outcomes After Submuscular Plating (SMP) of Pediatric Femoral Shaft Fractures.

BACKGROUND: To evaluate lower extremity strength and alignment among children who underwent submuscular plating (SMP). METHODS: Subjects who underwent SMP for a length unstable femoral fracture returned for isokinetic strength testing ≥2 years after surgery. Extensor and flexor strength deficits (percent difference) between the operative and nonoperative limbs were evaluated. Radiographic measurements of mechanical alignment [anatomic lateral distal femoral angle (aLDFA)] and qualitative measurements (The Pediatric Outcomes Data Collection Instrument, PODCI) were obtained from all subjects. The upper 97.5% confidence interval approach to establishing clinical equivalency was utilized to compare differences in strength and alignment between the operative and nonoperative limbs. An extensor strength deficit of >19% and an aLDFA discrepancy of >5 degrees were considered to be clinically significant. RESULTS: The average age at surgery of the 10 subjects included in the study was 8.7 years. The hardware was placed an average of 27.9 mm from the distal femoral physis and was removed 6.4 months postsurgery. Among all subjects, the median PODCI scores were ≥97 according to all subscales. There was no significant difference in extension torque between the operative versus nonoperative limbs at 60 degrees/s (P=0.5400), 120 degrees/s (P=0.4214), or 180 degrees/s (P=0.8166). More importantly, extension strength deficits between the operative and nonoperative limbs were not clinically significant at 60 degrees/s [upper 97.5% confidence interval (CI), 10.9%], 120 degrees/s (upper 97.5% CI, 11.0%), or 180 degrees/s (upper 97.5% CI, 10.7%). The difference in aLDFA between the operative and nonoperative limb was less than the predefined clinically significant threshold of 5 degrees for all subjects. CONCLUSIONS: SMP achieves satisfactory clinical and functional results. In this series, extensor strength deficits and/or lower extremity malalignment were not clinically meaningful. High patient satisfaction can be expected after implant removal. LEVEL OF EVIDENCE: Level IV-case series.

Reliability of the Modified Clavien-Dindo-Sink Complication Classification System in Pediatric Orthopaedic Surgery.

BACKGROUND: There is no standardized complication classification system that has been evaluated for use in pediatric or general orthopaedic surgery. Instead, subjective terms such as major and minor are commonly used. The Clavien-Dindo-Sink complication classification system has demonstrated high interrater and intrarater reliability for hip-preservation surgery and has increasingly been used within other orthopaedic subspecialties. This classification system is based on the magnitude of treatment required and the potential for each complication to result in long-term morbidity. The purpose of the current study was to modify the Clavien-Dindo-Sink system for application to all orthopaedic procedures (including those involving the spine and the upper and lower extremity) and to determine interrater and intrarater reliability of this modified system in pediatric orthopaedic surgery cases. METHODS: The Clavien-Dindo-Sink complication classification system was modified for use with general orthopaedic procedures. Forty-five pediatric orthopaedic surgical scenarios were presented to 7 local fellowship-trained pediatric orthopaedic surgeons at 1 center to test internal reliability, and 48 scenarios were then presented to 15 pediatric orthopaedic surgeons across the United States and Canada to test external reliability. Surgeons were trained to use the system and graded the scenarios in a random order on 2 occasions. Fleiss and Cohen kappa (κ) statistics were used to determine interrater and intrarater reliabilities, respectively. RESULTS: The Fleiss κ value for interrater reliability (and standard error) was 0.76 ± 0.01 (p < 0.0001) and 0.74 ± 0.01 (p < 0.0001) for the internal and external groups, respectively. For each grade, interrater reliability was good to excellent for both groups, with an overall range of 0.53 for Grade I to 1 for Grade V. The Cohen κ value for intrarater reliability was excellent for both groups, ranging from 0.83 (95% confidence interval [CI], 0.71 to 0.95) to 0.98 (95% CI, 0.94 to 1.00) for the internal test group and from 0.83 (95% CI, 0.73 to 0.93) to 0.99 (95% CI, 0.97 to 1.00) for the external test group. CONCLUSIONS: The modified Clavien-Dindo-Sink classification system has good interrater and excellent intrarater reliability for the evaluation of complications following pediatric orthopaedic upper extremity, lower extremity, and spine surgery. Adoption of this reproducible, reliable system as a standard of reporting complications in pediatric orthopaedic surgery, and other orthopaedic subspecialties, could be a valuable tool for improving surgical practices and patient outcomes.