Evidence Gaps in Total Hip Arthroplasty: A Registry-Based Study of Trial Discontinuation and Nonpublication From 2000 to 2024

BackgroundClinical trials play a vital role in advancing evidence-based orthopedic care, yet trial discontinuation and nonpublication limit transparency and reduce the availability of clinically valuable data.In total hip arthroplasty (THA), incomplete dissemination of trial outcomes may have important ethical and clinical implications. MethodsA registry-based cross-sectional analysis of randomized Phase III and IV THA clinical trials registered on ClinicalTrials.govbetween 2000 and 2024 was performed.Trials registered at least two years before the search date (January 2026) were included.Trial characteristics, including funding source, intervention type, enrollment size, blinding, number of centers, and recruitment location, were extracted.Publication status was determined through registry-linked publications and independent database searches.Associations were analyzed using chi-square or Fisher's exact tests (p < 0.05). ResultsOf 168 identified trials, seven unrelated to THA were excluded, leaving 161 trials for analysis.Fifty trials (31.1%) were discontinued, and 111 (68.9%) were completed.Among completed trials, 26 (23.4%) remained unpublished.Discontinuation was significantly associated with intervention type (p = 0.0015) and blinding (p = 0.022), with higher rates in device trials (59.3%) and unblinded studies (55.9%).Nonpublication was significantly associated with industry funding (39.3% vs. 18.1%, p = 0.022) and intervention type (p = 0.044). ConclusionsA substantial proportion of THA clinical trials are discontinued or remain unpublished, contributing to data loss and potential bias in the orthopedic literature.Improved reporting compliance is needed to support transparency and evidence-based orthopedic practice.