What is the prevalence of imaging-defined intra-articular hip pathologies in people with and without pain? A systematic review and meta-analysis

Background Intra-articular hip pathologies are thought to be associated with the development of hip and groin pain. A better understanding of the relationship between symptoms and imaging findings may improve the management of individuals with intra-articular hip pathologies. Objective To undertake a systematic review and meta-analysis to determine the prevalence of intra-articular hip pathologies in individuals with and without pain. Methods Seven electronic databases were searched in February 2017 for studies investigating the prevalence of intra-articular hip pathologies using MRI, MRA or CT. Two independent reviewers conducted the search, study selection, quality appraisal and data extraction. Metaanalysis was performed when studies were deemed homogenous, with a strength of evidence assigned to pooled results. Results In general, studies were moderate to high risk of bias, with only five studies adjudged to be low risk of bias. The 29 studies reporting on the prevalence of intraarticular hip pathologies identified limited evidence of a labral tear prevalence of 62% (95% CI 47% to 75%) in symptomatic individuals, with moderate evidence identifying a labral tear prevalence of 54% (95% CI 41% to 66%) in asymptomatic individuals. Limited evidence demonstrated a cartilage defect prevalence of 64% (95% CI 25% to 91%) in symptomatic individuals, compared with moderate evidence of a cartilage defect prevalence of 12% (95% CI 7% to 21%) in asymptomatic individuals. Conclusion The prevalence of intra-articular hip pathologies is highly variable in both symptomatic and asymptomatic populations. The prevalence of intra-articular hip pathologies appears to be higher in symptomatic individuals. However, imaging-defined intra-articular hip pathologies are also frequently seen in asymptomatic individuals, highlighting a potental discordant relationship between imaging pathology and pain. PROSPERO registration number CRD42016035444.