Braking function after complex lower extremity trauma.

BACKGROUND: This study was performed to evaluate when patients recover sufficiently to drive an automobile after operative repair of various other lower extremity fractures.

METHODS: A computerized driving simulator was developed and tested. Three groups of individuals were compared: (1) 12 healthy, volunteers tested once to establish normal mean values for variables tested (group I); (2) 22 patients with right-sided long bone lower extremity fractures (9 femur, 13 tibial shaft) tested at 6 weeks, 9 weeks, and 12 weeks after operative repair (group II); and 35 patients with right-sided articular fractures (12 plateau, 4 pilon, 12 calcaneus, 7 acetabulum) tested at 12 weeks, 15 weeks, and 18 weeks after operative repair (group III). Individuals were tested under a series of driving scenarios (city, suburban, and highway). Short musculoskeletal functional assessment scores were recorded at the time of each driving test and compared with results of the driving test. Analyses were performed to determine the relationship between time from initiation of weight bearing on the right lower extremity and brake travel time (BTT).

RESULTS: For group I, BTT was 302 +/- 90; for group II, BTT was 444 msec +/- 153 msec, 377 msec +/- 127 msec, and 359 msec +/- 116 msec at 6 weeks, 9 weeks, and 12 weeks after surgery; and for group III, BTT was 412 msec +/- 161 msec, 343 msec +/- 112 msec, and 339 msec +/- 116 msec at 12 weeks, 15 weeks, and 18 weeks after surgery. Short musculoskeletal functional assessment scores improved with respect to function and bother indexes, but did not correlate with improvement in BTT (r = 0.36, p = 0.07, and r = 0.31, p = 0.12, respectively).

CONCLUSION: BTT was significantly reduced until 6 weeks after initiation of weight bearing in both long bone and articular fractures of the right lower extremity.