OUTCOME OF SURGICAL TREATMENT IN PATIENTS WITH BORDERLINE ACETABULAR DYSPLASIA: A COMPARATIVE ANALYSIS OF HIP ARTHROSCOPY AND PERIACETABULAR OSTEOTOMY

Abstract

Background:Optimal treatments of patients with borderline hip dysplasia, defined as LCEA 20°-25°, is controversial. These patients can have symptomatic impingement and/or instability. The optimal treatment of either hip arthroscopy (HA) alone or periacetabular osteotomy (PAO) (with/without hip arthroscopy) has not been established.Purpose:The purpose of this study was to evaluate surgical outcomes of patients with borderline hip dysplasia at a minimum of 2-year follow-up.Methods:A longitudinal cohort was utilized to identify patients with borderline acetabular dysplasia defined via prospective radiographic measurements. Demographics and radiographic measurements were recorded. Patient evaluation, diagnosis and treatment decisions (PAO v HA) were made by one treating surgeon. Outcome were assessed at baseline and a minimum 2 years postoperative. Descriptive and comparative statistics were performed. Failure was defined as reoperation, or failure to reach mHHS MCID (8 points) or PASS (mHHS <74).Results:Total of 113 hips were included at 4.7 years postoperatively (range 2.0-11.2 years). Overall, 76% were female and 42% of hips had PAO (65% combined with hip arthroscopy), while 58% had isolated hip arthroscopy (HA). For PAO group, mHHS improved from 57.9 to 82.8 postoperatively, compared to 62.6 to 84.0 for the HA group. Similarly, HOOS pain (PAO 48.2 to 79.1, HA 61.2 to 82.0) and HOOS Sports (PAO 36.5 to 73.0, HA 47.8 to 74.4) demonstrated similar improvements. Comparing the PAO and HA groups, the change in PRO was significantly greater for the PAO group for HOOS Pain (10.5 ±23.2, p=0.02) and HOOS ADL (9.4 ±20.5, p=0.04) which was primarily due to a lower baseline score (similar final score). No significant difference was detected for other PROs. Reoperations in the PAO group were 2% (1 hip arthroscopy) and 6% for hip arthroscopy group (3 hip arthroscopies, 1 PAO). The failure rate was 17% for PAO and 15% for HA (p=0.86).Discussion:Surgical outcomes at minimum of 2 years in patients with borderline hip dysplasia in selected patients undergoing PAO or hip arthroscopy were good. Significant differences in patient characteristics and radiographic parameters were present between hips indicated for PAO vs. HA emphasizing the need for careful diagnosis and treatment decision-making.