High frequency of labral pathology in symptomatic borderline dysplasia: a prospective magnetic resonance arthrography study of 99 patients

The role of different acetabular morphologies on patient-reported outcomes following periacetabular osteotomy in borderline hip dysplasia

INTRODUCTION

The treatment option for borderline hip dysplasia (BHD) includes hip arthroscopy and periacetabular osteotomy (PAO). To the present day the controversial discussion remains, which intervention to prefer. Literature reports supporting an educated choice are scare, based on small patient cohorts and do not address the variability of acetabular morphology. Consequently, we intended to report PAO outcomes, from patients diagnosed with BHD, dependent on acetabular morphology, in a large patient cohort and aimed to define risk factors for poor clinical results and patient satisfaction.

MATERIALS AND METHODS

A prospective monocentre study was conducted. Patients enrolled underwent PAO for symptomatic BHD (LCEA, 18°-25°). A total of 107 hips were included with 94 complete data sets were available for evaluation with a minimum follow-up of 1 year and a mean follow-up of 2.3 years. The mean age was 31 ± 8.2 years, and 81.3% were female. As the primary outcome measure, we utilized the modified Harris hip score (mHHS) with minimal clinically important change (MCID) of eight to define clinical failure. Results were compared after a comprehensive radiographic assessment distinguishing between lateral deficient vs. anterior/posterolateral deficient acetabular and stable vs. unstable hip joints.

RESULTS

Overall, clinical success was achieved in 91.5% of patients and the mHHS improved significantly (52 vs. 84.7, p < 0.001). Eight hips failed to achieve the MCID and four had radiographic signs of overcorrection. Comparing variable joint morphologies, the rate of clinical success was higher in patients with an anterior/posterolateral deficient acetabular covarage compared to lateral deficient acetabular (95.2% vs. 90.4%). tThe highest rate of clinical failure was recorded in unstable hip joints (85.7% vs. 92.5% in stable hips).

CONCLUSIONS

This study demonstrates that PAO is an effective means to treat symptomatic BHD with variable acetabular morphologies, achieving a clinical success in 91.5% of all patients. To maintain a high level of safety and patient satisfaction technical accuracy appears crucial.

The incidence of subsequent hip arthroscopy after rectus-sparing periacetabular osteotomy

Aims

Periacetabular osteotomy (PAO) is the preferred treatment for symptomatic acetabular dysplasia in adolescents and young adults. There remains a lack of consensus regarding whether intra-articular procedures such as labral repair or improvement of femoral offset should be performed at the time of PAO or addressed subsequent to PAO if symptoms warrant. The purpose was to determine the rate of subsequent hip arthroscopy (HA) in a contemporary cohort of patients, who underwent PAO in isolation without any intra-articular procedures.

Methods

From June 2012 to March 2022, 349 rectus-sparing PAOs were performed and followed for a minimum of one year (mean 6.2 years (1 to 11)). The mean age was 24 years (14 to 46) and 88.8% were female (n = 310). Patients were evaluated at final follow-up for patient-reported outcome measures (PROMs). Clinical records were reviewed for complications or subsequent surgery. Radiographs were reviewed for the following acetabular parameters: lateral centre-edge angle, anterior centre-edge angle, acetabular index, and the alpha-angle (AA). Patients were cross-referenced from the two largest hospital systems in our area to determine if subsequent HA was performed. Descriptive statistics were used to analyze risk factors for HA.

Results

A total of 16 hips (15 patients; 4.6%) underwent subsequent HA with labral repair and femoral osteochondroplasty, the most common interventions. For those with a minimum of two years of follow-up, 5.3% (n = 14) underwent subsequent HA. No hips underwent total hip arthroplasty and one revision PAO was performed. Overall, 17 hips (4.9%) experienced a complication and 99 (26.9%) underwent hardware removal. All PROMs improved significantly postoperatively. Radiologically, 80% of hips (n = 279) reached the goal for acetabular correction (77% for acetbular index and 93% for LCEA), with no significant differences between those who underwent subsequent HA and those who did not.

Conclusion

Rectus-sparing PAO is associated with a low rate of subsequent HA for intra-articular pathology at a mean of 6.2 years' follow-up (1 to 11). Acetabular correction alone may be sufficient as the primary intervention for the majority of patients with symptomatic acetabular dysplasia.

Outcomes and Return-to-Sports Rates in Patients With Borderline Hip Dysplasia After Periacetabular Osteotomy: A Case Series With 5-Year Follow-up

BACKGROUND

The optimal surgical approach in patients with borderline hip dysplasia (BHD) remains controversial. Both hip arthroscopy and periacetabular osteotomy (PAO) are commonly employed in this patient population. Those who participate in sports want to resume and maintain sports activities after surgery, and the ability to do so plays an important role in the choice of a treatment method. To our knowledge, no previous study has assessed return-to-sports rates and activity levels in patients with BHD after PAO.

PURPOSE

To assess return-to-sports rates and postoperative activity levels as measured by the University of California, Los Angeles (UCLA), activity scale as well as patient-reported outcome measures. Also to assess changes in sports activity both qualitatively and quantitatively as well as underlying reasons for these changes.

STUDY DESIGN

Case series; Level of evidence, 4.

METHODS

We conducted a retrospective analysis of prospectively collected data from 55 hips in 52 patients with BHD who underwent PAO between January 2015 and June 2017. Return-to-sports rates, UCLA activity scores, International Hip Outcome Tool-12 scores, Subjective Hip Value scores, Hip disability and Osteoarthritis Outcome Score subscores, sports practiced, frequency and duration of sports activity, and postoperative changes as well as underlying reasons were recorded.

RESULTS

The mean follow-up was 62.8 ± 9.0 months. The return-to-sports rate among preoperatively active patients was 92.5%. Most patients resumed sports activity after 6 months (50%) or after 3 to 6 months (37.5%). The UCLA activity score improved significantly (from 5.2 ± 2.4 to 7.0 ± 1.8; P < .001). The International Hip Outcome Tool-12, Subjective Hip Value, and Hip disability and Osteoarthritis Outcome Score scores also improved significantly (all, P < .001). Changes in sports activity occurred in 34.5% of cases after PAO. Significantly more patients engaged in low-impact sports postoperatively. Participation in high-impact sports did not decrease significantly. Reasons for changes were both hip related and non-hip related. Quantitatively, patients were able to significantly increase both the frequency (P = .007) and duration (P = .007) of sports activity.

CONCLUSION

The return-to-sports rate in patients with BHD after PAO was high at over 92%. Most patients returned to sports after a period of 6 months or 3 to 6 months. Overall, activity levels and hip function improved after PAO. A number of patients adjusted their sports activity after PAO. Although more patients engaged in low-impact sports, participation in high-impact sports was maintained postoperatively. The results of this study may help both patients and orthopaedic surgeons in deciding on the best surgical procedure in the setting of BHD.

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

BACKGROUND

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

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

REGISTRATION

PROSPERO (CRD42020144748).

Does hip muscle strength and functional performance differ between football players with and without hip dysplasia?

OBJECTIVE

To compare hip muscle strength and functional performance in football players with and without hip dysplasia and investigate if the relationships were modified by sex.

DESIGN

Cross-sectional study.

METHODS

This study compared football players with hip dysplasia (HD group) and without hip dysplasia (control group). Hip muscle strength (Nm/kg) and functional task performance were assessed in both groups. Linear regression with generalized estimating equations were used to assess differences between groups. Sex was assessed as a potential effect modifier.

RESULTS

101 football players were included (HD group, n = 50, control group, n = 51). There was no difference in hip muscle strength or functional performance between the HD group and the control group. Results ranged from hip extension strength (Estimate -0.13.95%CI: 0.29 to 0.02, P = 0.087) to hip external rotation strength (Estimate 0.00.95%CI: 0.05 to 0.05, P = 0.918). No relationships were modified by sex or age.

CONCLUSIONS

Similar levels of hip muscle strength and functional performance were found in active football players with and without hip dysplasia. These findings differ from other studies. This may be due to our cohort having less advanced hip dysplasia than the surgical populations that have been previously investigated, or due to a beneficial effect of football participation on muscle strength and functional performance in people with hip dysplasia.

Factors influencing patient-reported outcomes following periacetabular osteotomy and open osteochondroplasty in the setting of borderline hip dysplasia

Aims

This study reports mid-term outcomes after periacetabular osteotomy (PAO) exclusively in a borderline hip dysplasia (BHD) population to provide a contrast to published outcomes for arthroscopic surgery of the hip in BHD.

Methods

We identified 42 hips in 40 patients treated between January 2009 and January 2016 with BHD defined as a lateral centre-edge angle (LCEA) of ≥ 18° but < 25°. A minimum five-year follow-up was available. Patient-reported outcomes (PROMs) including Tegner score, subjective hip value (SHV), modified Harris Hip Score (mHHS), and Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) were assessed. The following morphological parameters were evaluated: LCEA, acetabular index (AI), α angle, Tönnis staging, acetabular retroversion, femoral version, femoroepiphyseal acetabular roof index (FEAR), iliocapsularis to rectus femoris ratio (IC/RF), and labral and ligamentum teres (LT) pathology.

Results

The mean follow-up was 96 months (67 to 139). The SHV, mHHS, WOMAC, and Tegner scores significantly improved (p < 0.001) at last follow-up. According to SHV and mHHS, there were three hips (7%) with poor results (SHV < 70), three (7%) with a fair score (70 to 79), eight (19%) with good results (80 to 89), and 28 (67%) who scored excellent (> 90) at the last follow-up. There were 11 subsequent operations: nine implant removals due to local irritation, one resection of postoperative heterotopic ossification, and one hip arthroscopy for intra-articular adhesions. No hips were converted to total hip arthroplasty at last follow-up. The presence of preoperative labral lesions or LT lesions did not influence any PROMs at last follow-up. From the three hips that had poor PROMs, two have developed severe osteoarthritis (> Tönnis II), presumably due to surgical overcorrection (postoperative AI < -10°).

Conclusion

PAO is reliable in treating BHD with favourable mid-term outcomes. Concomitant LT and labral lesions did not negatively influence outcomes in our cohort. Technical accuracy with avoidance of overcorrection is essential in achieving successful outcomes.

Outcomes of Periacetabular Osteotomy for Borderline Acetabular Dysplasia

BACKGROUND

The optimal surgical treatment (hip arthroscopy compared with periacetabular osteotomy [PAO]) for borderline acetabular dysplasia (lateral center-edge angle [LCEA], 18° to 25°) remains a topic of debate. To date, the literature has focused primarily on arthroscopy outcomes, with only a few small reports on PAO outcomes. The purpose of this study was to define PAO outcomes in a large cohort of borderline hips. In a secondary analysis, we assessed the effect of prior failed arthroscopy, concurrent hip arthroscopy, and concurrent femoral osteoplasty on PAO outcomes in this cohort.

METHODS

A prospective database was retrospectively reviewed for patients who underwent PAO for symptomatic instability in the setting of borderline dysplasia (LCEA, 18° to 25°). Of the 232 identified hips, 186 (80.2%) were assessed at a mean follow-up of 3.3 ± 2.0 years postoperatively. The mean patient age was 25.2 ± 8.5 years (range, 14 to 45 years), and 88.2% were female. Thirty hips (16.1%) had undergone a failed prior arthroscopy. Arthroscopy was performed concurrently with the PAO in 130 hips (69.9%), and femoral osteoplasty was performed concurrently in 120 hips (64.5%). The modified Harris hip score (mHHS) was assessed relative to the minimal clinically important difference (MCID) of 8 and patient acceptable symptom state (PASS) of 74. Clinical failure was defined as a reoperation for persistent symptoms or a failure to achieve either the mHHS MCID or PASS.

RESULTS

Of the 156 hips undergoing a primary surgical procedure, clinical success was achieved in 148 hips (94.9% [95% confidence interval (CI), 90.2% to 97.4%]). Two hips (1.3% [95% CI, 0.4% to 4.6%]) underwent reoperation (hip arthroscopy) for persistent symptoms and an additional 6 hips (3.8% [95% CI, 1.8% to 8.1%]) failed to achieve the mHHS MCID or PASS, for a clinical failure rate of 5.1% (95% CI, 2.6% to 9.8%); 8.8% reported dissatisfaction with the surgical procedure. Clinical failure was more frequent among the 30 hips (23.3% [95% CI, 11.8% to 40.9%]; p = 0.001) that had undergone a prior failed arthroscopy. There were no outcome differences between hips that had or had not undergone concurrent hip arthroscopy or femoral osteoplasty.

CONCLUSIONS

This study demonstrates excellent early outcomes of PAO for borderline acetabular dysplasia, with significant clinical improvement in 94.9% of patients undergoing a primary surgical procedure; 91.2% were satisfied with the surgical procedure.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Physical impairments in Adults with Developmental Dysplasia of the Hip (DDH) undergoing Periacetabular osteotomy (PAO): A Systematic Review and Meta-Analysis

Background

Developmental dysplasia of the hip (DDH) is a condition associated with hip pain and impairments. Periacetabular osteotomy (PAO) is a common surgical treatment for DDH. Outcomes following PAO have historically been based on radiology or patient reported outcomes, and not physical impairments.

Objective

To investigate differences in physical impairments in adults with DDH undergoing PAO compared with asymptomatic participants, and to investigate pre- to post-PAO changes in physical impairments.

Design

Systematic review with meta-analysis.

Methods

A literature search was performed in five databases (MEDLINE, CINAHL, EMBASE, Sports Discuss, and PsychINFO), using the PRISMA checklist. Studies were considered eligible if patients were aged 15 years and older, treated with PAO for DDH and if they included a physical impairment outcome measure. Two independent reviewers performed data extraction and assessed methodological quality, using a modified version of the Downs and Black checklist.

Results

Of 5,017 studies, 24 studies were included with 2190 patients. The methodological quality scores ranged from 39% to 88%. With low level of evidence, meta-analysis showed 58% of patients had a positive anterior impingement test (95%CI: 39-76%), prior to PAO and one to three years after PAO. Five years after PAO, the proportion fell to 17% (95%CI: 11-24%). Prior to PAO, patients with DDH walked with a lower peak hip extension angle, compared to asymptomatic participants (SMD 0.65 (95%CI 0.21-1.10). Best evidence synthesis of non-pooled data showed limited evidence of increased walking velocity, stride length and improved hip flexion and extension moment 18-months post-PAO compared to pre-op. Cadence, hip abduction and hip flexion strength did not change.

Conclusion

Most patients with DDH have a positive hip impingement test, pre-PAO. Compared to asymptomatic participants, patients with DDH demonstrate physical impairments during walking which appear to improve after surgery. Hip abduction and flexion strength did not change pre- to post-PAO.

Level of Evidence

1b.

Rate of continued conservative management versus progression to surgery at minimum one year follow-up in patients with pre-arthritic hip pain

INTRODUCTION

Extensive literature has described surgical outcomes for pre-arthritic hip pain, but the proportion of patients who progress to surgery remains unknown.

OBJECTIVE

To determine the proportion of patients who present to a tertiary referral center for pre-arthritic hip pain and progress to surgery at minimum one year follow-up.

DESIGN

Retrospective cohort study.

SETTING

Single tertiary care academic medical center.

PATIENTS

Thirteen to 40-year-olds who presented for initial evaluation to a conservative or surgical orthopedic specialist and were diagnosed with pre-arthritic hip pain (n=713 patients, 830 hips).

INTERVENTION

Not applicable.

MAIN OUTCOME MEASURES

The primary outcome was the rate of progression to surgery at minimum one year follow-up for the entire cohort. Predictors of progression to surgery were determined for the entire cohort and for radiographically defined subgroups using multiple logistic regression. Candidate predictors included baseline demographic, radiographic, clinical diagnosis, and patient-reported outcome measures.

RESULTS

In a cohort with mean age 25.4 (SD 8.1) years, 72.7% female, and mean follow-up 2.6 (range 1.0-4.8) years, 429/830 hips (51.7% [95% CI 48.2%-55.1%]) progressed to surgery. Predictors of surgical progression in the entire cohort included younger age (OR 0.95/year [95% CI 0.93-0.98]), pain duration longer than six months (OR 1.87-2.03, p≤.027), worse physical function (OR 0.96/Patient-Reported Outcomes Measurement Information System (PROMIS) point [0.92-0.99]), and a clinical diagnosis of femoroacetabular impingement (FAI) (OR 3.47 [2.05-5.89]), acetabular dysplasia (OR 2.75 [1.73-4.35]), and/or labral tear (OR 10.71 [6.98-16.47]). Radiographic dysplasia (lateral center edge angle<20⁰ ) increased the likelihood of surgery in all subgroups (OR 2.05-8.47, p≤.008). Increasing maximum α angle increased the likelihood of surgery in patients with severe cam FAI (α>63⁰ ) (OR 1.03/degree [1.00-1.06]).

CONCLUSION

Almost half of patients with pre-arthritic hip pain did not progress to surgery at minimum one year follow-up. A trial of conservative management is likely worthwhile in most patients. This article is protected by copyright. All rights reserved.

Impact of bone deformities and labral and cartilage lesions on early functional results of arthroscopic treatment of femoroacetabular impingement

INTRODUCTION

Femoroacetabular impingement (FAI) is a frequent cause of inguinal pain. Treatment failure rates range between 2.9% and 13.2%. The aim of the present study was to assess the impact of preoperative bone deformities (BD), labral lesions (LL) and cartilage lesions (CL) on clinical results of arthroscopic treatment of FAI.

MATERIAL AND METHOD

A prospective operational study included patients undergoing hip arthroscopy for FAI. All patients had full radiographic work-up and clinical assessment on Non-Arthritic Hip Score (NAHS), preoperatively and at 1year. Hips with Tönnis grade>1, coxa profunda [VCE (vertical center edge angle)>35°] or borderline dysplasia (VCE<25°) were excluded. The Czerny classification was used for the labrum and the Beck classification for the cartilage. The aim of the study was to assess the impact of preoperative BD, LL and CL on clinical results of arthroscopic treatment of FAI. The study hypothesis was that type of lesion does not influence early functional results at 1year, whatever the technique used for the labrum.

RESULTS

One hundred and ninety-seven patients were included. Mean preoperative NAHS was 59.1±17.5. There were 145 patients with labral suture (73.6%), 42 with labral debridement (21.3%) and 10 with conservative treatment (5.1%). At 1year, mean NAHS was 88.1±15.3: i.e., a significant improvement (p<2.2×10^-16). Improvement was also significant in the debridement, non-operative and suture subgroups. BD showed significant correction in the overall population (alpha angle 48.2° postoperatively versus 66.7° preoperatively; crossing sign in 14.5% versus 62.9% of cases). There were no significant differences in functional scores according to extension or type of labral or cartilage lesion. At follow-up, 3 patients (1.5%) required repeat arthroscopy.

CONCLUSION

The present study showed that early functional results of arthroscopic treatment of FAI were unaffected by the severity of bone deformity (alpha and VCE angles), or extension or type of labral or cartilage lesion. Regardless of BD, LL and CL, 1-year clinical progression was satisfactory when all bone deformities were treated by the arthroscopic procedure.

LEVEL OF EVIDENCE

IV; prospective non-comparative study.

Tönnis Grade 1 dysplastic hips have improved patient-reported outcome scores when intraarticular pathology is treated during periacetabular osteotomy

It is unclear whether treatment of intraarticular pathology should be performed during periacetabular osteotomy (PAO) to improve outcomes. Therefore, we asked: (i) What are the clinical results of PAO in patients with and without intraarticular intervention? (ii) Is there a difference in reoperations with and without intraarticular intervention? and (iii) Is there a difference in clinical results and reoperations depending on preoperative Tönnis Grade if intraarticular intervention is performed? Prospective evaluation of 161 PAO in 146 patients was performed. The cohort was 84.5% female, mean age was 26.7 ± 7.9 years and mean follow-up was 2.4 years; 112 hips had Grade 0 changes and 49 hips had Grade 1 changes. Patients were classified into three groups based on treatments during PAO: major (labral repair, femoral head–neck osteochondroplasty), minor (labral debridement, femoral/acetabular chondroplasty) or no intervention. A subset of eight patient-reported outcome measures (PROMs) was analyzed to determine whether the minimal clinically important difference (MCID) was achieved. Major, minor and no intervention groups exceeded the MCID in 5, 8 and 8, of 8 PROMs (P ≥ 0.20), respectively; intraarticular interventions did not influence reoperation-free survival (P ≥ 0.35). By Tönnis Grade, PROMs exceeding MCID decreased in Grade 1 versus 0 receiving no intervention (P &lt; 0.001) but did not decrease for either intervention (P ≥ 0.14); intraarticular interventions did not influence reoperation-free survival (P ≥ 0.38). Overall, intraarticular intervention was associated with excellent PROMs and reoperation-free survival. Although Grade 1 patients had fewer PROM which achieved MCID, intraarticular interventions attenuated this decrease, suggesting a therapeutic advantage of intraarticular procedures for more advanced pathology.

Comparison Between Hip Arthroscopic Surgery and Periacetabular Osteotomy for the Treatment of Patients With Borderline Developmental Dysplasia of the Hip: A Systematic Review

Background:

The treatment for borderline developmental dysplasia of the hip (BDDH) has historically been arthroscopic surgery or periacetabular osteotomy (PAO). As orthopaedic surgery is constantly evolving, a lack of comparison of outcomes for these 2 treatment methods could potentially be stalling the progression of treatment for patients with BDDH.

Purpose:

To evaluate the existing literature on patient characteristics, procedures, clinical outcomes, and failure rates for patients with BDDH and to determine whether PAO or hip arthroscopic surgery is a better treatment method for patients with BDDH.

Study Design:

Systematic review; Level of evidence, 4.

Methods:

Studies included were found using the following search words: “hip” and “borderline dysplasia,” “osteotomy” or “arthroscopy,” and “outcome” or “procedure.” Articles were included if they detailed participants of all sexes and ages, reported on isolated hips, and had patients diagnosed with BDDH.

Results:

A search was conducted across 3 databases, resulting in 469 articles for consideration, from which 12 total studies (10 on arthroscopic surgery and 2 on PAO) were chosen for a review. There were 6 studies that included patients with a lateral center-edge angle of 18° to 25°, while the remainder included patients with a lateral center-edge angle of 20° to 25°. All the studies reviewing arthroscopic surgery reported concomitant/accessory procedures, while the articles on the topic of PAO did not. It was determined that, whether treated using arthroscopic surgery or PAO, outcomes improved across all patient-reported outcome measures. Revision surgery was also common in both procedures.

Conclusion:

There is a lack of consensus in the literature on the best treatment option for patients with BDDH. Preoperative patient characteristics and concomitant injuries should be considered when evaluating which surgical procedure will result in the most favorable outcomes.

The lateral center-edge angle as radiographic selection criteria for periacetabular osteotomy for developmental dysplasia of the hip in patients aged above 13 years

Background

This retrospective study sought to delineate the radiographic characteristics of DDH patients over 13 years of age and investigate whether the lateral center-edge angle (LCEA) could serve as radiographic selection criteria for periacetabular osteotomy.

Methods

We enrolled patients with Hartofilakidis type I DDH without dislocation who underwent periacetabular osteotomy between August 2009 and August 2012. LCEA, anterior central edge angle (ACEA), femoral neck-shaft angle (FNSA), Shenton line and Tönnis acetabular index (AI) were evaluated by anteroposterior and 65° false⁃profile pelvic X-ray radiographs in the standing position. Femoral neck anteversion angle (FNA), labral lesion, labral inversion and cartilage lesion were evaluated by direct magnetic resonance arthrography. DDH was categorized by LCEA into four grades (grade I: 10° ≤ LCEA< 20°, grade II: 0° ≤ LCEA< 10°, grade III: -10° ≤ LCEA< 0°, grade IV: LCEA<-10) and osteoarthritis (OA) severity was assessed using Tönnis OA classification. Pearson correlation analysis was done between LCEA and other variables.

Results

Totally patients (274 hips) with a mean age of 27.3 years (range 13–47 years) were included. The mean LCEA was 3.5° (range: − 30° to 20°). Based on LCEA grades, grade I DDH was present in 104 hips, grade II in 40 hips, grade III in 76 hips, and grade IV in 54 hips. Based on Tönnis OA classification, 54.5% hips (150/274) were grade 0, 33.1% hips (91/274) grade 1, 8.4% hips (23/274) grade 2 and 4% hips (11/274) grade 3. Pearson correlation analysis showed a negative correlation between LCEA grade and Tönnis OA grades (r = 0.3987; P < 0.001). Cochran-Armitage trend test further showed a positive correlation between LCEA grades and labral lesion (P < 0.001) and interrupted Shenton line (P < 0.001).

Conclusion

The LCEA classification scheme offers a simple and practical approach to categorize the level of acetabulum coverage on the femoral head, hip deformity and characteristics of DDH. Our findings could provide clinically useful guidance for orthopedic surgeons in preparation for periacetabular osteotomy in DDH patients aged above 13 years.

Outcomes of periacetabular osteotomy for borderline hip dysplasia in adolescent patients

Treatment of borderline acetabular dysplasia (lateral center edge angle ≥18°) remains controversial, and there is a paucity of literature focusing on outcomes in adolescent patients. The purpose of this study was to evaluate the outcomes of a periacetabular osteotomy (PAO) as surgical management of borderline acetabular dysplasia in adolescent patients. We performed a retrospective review of prospectively collected data and included patients ≤ 21 years of age that underwent PAO for borderline acetabular dysplasia. All patients had a minimum of 1-year follow-up. Outcomes were assessed using modified Harris Hip Scores (mHHS), Hip Outcome Scores (HOS) and international Hip Outcome Tool (iHOT-33). Descriptive and univariate statistical analyses were performed. This study included 33 adolescent patients (35 hips) with symptomatic, borderline acetabular dysplasia. The majority of patients was female (32 patients, 97%); half of all patients reported a history of hip pain for over 1 year; and seven patients had previous hip arthroscopy. In addition to PAO, seven hips (20%) underwent a concurrent hip arthroscopy at the time of surgery. There were significant improvements in mean mHHS, HOS-activities of daily living (ADL), HOS-Sport and iHOT-33 scores after surgery (P < 0.01). Minimal clinically important difference in outcome scores was achieved for over 90% of patients at a minimum of 1-year follow-up. Borderline acetabular dysplasia is a major cause of hip pain in adolescent patients. Patients with symptomatic borderline acetabular dysplasia report a significant benefit after a PAO to correct structural hip instability.