Abstract
According to Chow et al's classification, type I fractures of the middle phalanx have no associated tendon injury or extensive skin loss, which required reconstruction. Despite the favorable soft-tissue conditions, a rate of poor outcome as 25% has been observed, and the reason for this is unknown. The aim of this study is to test our hypothesis that type I fractures may be subclassified into following 2 types: type IA and type IB, based on the absence or presence of concurrent significant "soft-tissue crush," respectively. Type IB fractures are hypothesized to have a worse outcome. Significant soft-tissue crush is diagnosed clinically by the presence of severe swelling and/or superficial skin injury (not requiring reconstruction). In a prospective study, 29 type I extraarticular fractures of the middle phalanx in adult industrial workers were included and classified into the following 2 groups: type IA (n = 16 fingers) and type IB (n = 13 fingers). All were treated with closed reduction and longitudinal Kirschner wire fixation. The outcome in range of motion was measured, and time to return to work was recorded. At final follow-up, the mean total active motion of the injured fingers was 241.3 degrees in group IA and 186.9 degrees in group IB (P < 0.001 by Mann-Whitney U test). Furthermore, group A patients returned to work earlier than group B (15.1 vs. 26.8 weeks, P < 0.001 by Mann-Whitney U test). It was concluded that severe swelling and superficial skin injury significantly affect the outcome of type I extraarticular fractures of the middle phalanx treated by closed reduction and longitudinal Kirschner wire fixation.