International trends in arthroscopic hip preservation surgery--are we treating the same patient?

The goal of this study was to perform a systematic review and meta-analysis of the entire arthroscopic hip preservation literature to answer the question, 'Across the world, are we treating the same patient?' There are significant differences in arthroscopic hip preservation publications, subjects and techniques based on both continent and country published. A systematic review was registered with PROSPERO and performed with PRISMA guidelines using three publicly available databases. Therapeutic clinical outcome investigations reporting arthroscopic hip preservation were eligible for inclusion. All study, subject and surgical technique demographics were analyzed and compared between continents and countries. Statistics were calculated using Student's t-tests, one-way analysis of variance, chi-squared and two-proportion Z-tests. There were 134 studies included in the analysis (10 752 subjects; 11 007 hips; 51% female; mean 37.6 years of age; mean 27.2 months length of follow-up), which had a low Modified Coleman Methodology Score (mean 32.4; poor). North America published the largest number of studies (58%) and the most subjects (55%) and hips (56%). Australia (22%) and Europe (18%) operated on subjects with some amount of osteoarthritis most commonly. North America (2.7%) and Europe (2.0%) operated on subjects with dysplasia or borderline dysplasia most commonly. The Modified Harris Hip Score was the most frequently utilized outcome score (24% of studies). The quantity and quality of arthroscopic hip preservation literature is significantly increasing with time. Several significant differences in study, subject and surgical technique demographics between continents and countries were identified. Deficiencies in use of clinical outcome scores and definitions of treated pathologies preclude complete subject comparisons and serve as an impetus for future study quality improvements.