A Prospective Analysis of Patient Characteristics Affecting the Outcome of Dorsal Splinting for Soft Tissue Mallet Injuries.

Background: Much has been written about the diagnosis and treatment of soft tissue mallet injuries. However, there has been little regarding the characteristics of this injury affecting patients' prognosis. The purpose of this prospective study was to identify factors influencing the outcome of treatment of soft tissue mallet injuries.

Methods: Patients diagnosed with soft tissue mallet injuries were enrolled prospectively in a protocol of dorsal splinting for 6 to 12 weeks, followed by weaning over 2 weeks and then evaluated at 6, 9, and 12 months.

Results: Thirty-seven patients (38 digits) completed the study. Treatment success was defined as a final extensor lag of <15° and failure as a final extensor lag of 15°. Those failing splint treatment were older compared with those successfully treated. Patient compliance was significantly associated with a successful outcome. Factors that did not significantly affect success included time to treatment, initial injury severity, splinting duration, sex, and ligamentous laxity. Disabilities of Arm, Shoulder, and Hand scores >0 were not associated with treatment failure. Radiographic and clinical extension lag were statistically comparable.

Conclusions: This study shows strong association between the success of splint treatment, younger patient age, and compliance with the treatment protocol. Despite this finding, most patients did not report any functional limitations, irrespective of the treatment success. In contrast to prior results, time to treatment and initial extensor lag did not significantly affect treatment success.