Slutsky DJ, South Bay Hand Surgery Center, 3475 Torrance Blvd, Ste F, Torrance, CA, USA
Purpose: A hand injury severity score relating the severity of injury to time off work has been described with validation by a surgeon survey and chart review. The purpose of the present study was to examine the effect of various poor prognostic factors on the total active motion (TAM) and to devise a prognostic scoring system validated by the data. Methods: A retrospective study of 94 patients with104 unstable phalangeal and metacarpal fractures that underwent internal fixation was performed. The fractures were subdivided into 4 groups based on the TAM:<180(poor);180-219(fair);220-239(good);>240(excellent).Various fracture factors that have been previously identified in the literature to adversely affect the TAM were analyzed using multivariate linear and logistic regression. Results: There were 63 patients with phalangeal fractures and 31 patients with metacarpal fractures. Forty-two fractures were stabilized with minicondylar plates and the rest with screws, k-wires and other plates. The average TAM score was 184 degrees for the phalangealand 223 degrees for the metacarpal group.Analysis of the phalangeal group revealed the following variables resulted in significantly lower TAM scores; periarticular location (N=18), comminution (N=35) open fractures (N=26), flexor laceration (N=7), extensor laceration (N=17), artery laceration (N=7), nerve laceration (N=7), crushing mechanism (N=18), combined periarticular location with crush (N=7) and extensor tendon graft (N=9). The following variables independently contributed to a reduction in the TAM; open fractures (p=0.000), comminution (p=0.006), delay > 21 days (p=0.054), periarticular location (p=0.079) and proximal phalanx fractures (p=0.110). Based on this a multivariate risk score for phalangeal fractures was developed as follows: periarticular and proximal phalanx=1 point, periarticular and comminution=2 points, and open fractures=3 points. The only variable associated with a lower TAM score in the metacarpal group was extensor tendon laceration (N=19) and extensor tendon graft (N=10). As in other studies, the results of metacarpal fractures were superior to phalangeal fractures with comparable risk factors. Discussion: The Phalangeal Risk Score (PRS) is not an absolute indicator of the final TAM since good results were achieved in some fractures with higher scores. Individual patient factors such as pain tolerance, motivation and inherent fibroblastic response may play a role. Despite this, the PRS can provide prognostic information as to the ultimate digital motion at the time of the initial injury.