Clinical trials play a crucial role in advancing medical knowledge and have the potential to change standards of care. The present study evaluated the prevalence of discontinued clinical trials in orthopaedic surgery. Additionally, we sought to identify the study characteristics associated with and the rationale behind trial discontinuation.

A cross-sectional survey of orthopaedic clinical trials using the ClinicalTrials.gov registry and results database was performed for trials between October 1, 2007, and October 7, 2022. Interventional trials listed as “completed,” “terminated,” “withdrawn,” or “suspended” were included. Study characteristics were collected and clinical trial abstracts were reviewed in order to assign the appropriate subspecialty category. A univariate linear regression analysis was performed to determine whether the percentage of discontinued trials changed between 2008 and 2021. Univariate and multivariable hazard ratios (HRs) were calculated to identify factors associated with trial discontinuation.

A total of 8,603 clinical trials were included in the final analysis, of which 1,369 (16%) were discontinued, with the highest rates of discontinuation found in oncology (25%) and trauma (23%). The most common rationales for discontinuation were insufficient patient accrual (29%), technical or logistical issues (9%), business decision (9%), and lack of funding or resources (9%). Industry-funded studies were more likely than government-funded studies to be discontinued (HR: 1.81; p < 0.001). There was no change in the percentage of discontinued trials for each orthopaedic subspecialty between 2008 and 2021 (p = 0.21). As shown on multivariable regression analysis, trials for devices (HR: 1.63 [95% confidence interval, 1.20 to 2.21]; p = 0.002) and drugs (HR: 1.48 [1.10 to 2.02]; p = 0.013) as well as Phase-2 trials (HR: 1.35 [1.09 to 1.69]; p = 0.010), Phase-3 trials (HR: 1.39 [1.09 to 1.78]; p = 0.010), and Phase-4 trials (HR: 1.44 [1.14 to 1.81]; p = 0.010) had a higher likelihood of early discontinuation. However, pediatric trials were less likely to be discontinued (HR: 0.58 [0.40 to 0.86]; p = 0.007).

The results of the present study suggest the need for continued efforts to ensure the completion of orthopaedic clinical trials in order to limit publication bias and to employ resources and patient contributions more efficiently for research.

Discontinued trials contribute to publication bias, which limits the comprehensiveness of the literature available to support evidence-based patient care interventions. Therefore, identifying the factors associated with and the prevalence of orthopaedic trial discontinuation encourages orthopaedic surgeons to design future trials to be more resistant to early discontinuation.