OBJECTIVE: Capener splinting is a common treatment for extension deficit of the proximal interphalangeal (PIP) joint. This study compared the effect of daily splint total end range time (TERT) of 6-12 hr versus 12-16 hr. METHOD: Twenty-two participants with extension deficits of the PIP joint were randomly allocated to a daily TERT of 6-12 hr or 12-16 hr. Progress after 8 wk of splinting was evaluated. RESULTS: No significant difference was found in change in extension range of motion (ROM) between groups (active ROM, F[4, 17] = 2.19, p = .13; passive ROM, F[4, 17] = 0.95, p = .46; torque ROM, F[4, 17] = 1.49, p = .26). Considerable crossover between groups resulted in a similar average daily TERT (9.5 hr for the 6-12 hr group vs. 11.5 hr for the 12-16 hr group). CONCLUSION: Further research with a larger sample is needed to determine whether longer daily TERT is beneficial. Our results suggest, however, that most patients find it difficult to wear splints >12 hr/day.