Determining a Timeline for Returning to Driving After a Right Femoral Fracture: A Braking Simulator-Based Study

OBJECTIVES: To determine when patients with surgically treated right femoral fractures achieve objective criteria for driving readiness after surgery. METHODS: Design: Prospective cohort study. SETTING: Single Level I trauma center. PATIENT SELECTION CRITERIA: Patients aged ≥18 years who are licensed drivers and sustained a surgically treated right femoral fracture (OTA/AO 31-33) at a single Level I trauma center were prospectively enrolled after surgery between 2020 and 2024 and underwent braking simulator testing during postoperative follow-up visits. Patients were weight-bearing as tolerated at the time of testing, and those with associated fractures or neurologic deficits were excluded. OUTCOME MEASURES AND COMPARISONS: Brake reaction time (BRT) and maximum brake force (BF) were measured using a custom braking simulator during postoperative visits. Driving readiness was defined as BRT <1 second and BF >350 N, consistent with conservative published thresholds. Patients were classified as meeting both thresholds (I), BRT only (II), BF only (III), or neither (IV), and category distributions were reported across four postoperative intervals: 1-25, 26-75, 76-125, and >125 days. RESULTS: Forty-five patients were included in this study. Patients were 23 females and 22 males, with a mean age of 58.9 years (range, 18-90). The number of simulator tests performed was 18 at 1-25 days, 33 at 26-75 days, 25 at 76-125 days, and 24 at >125 days. Within the first 25 postoperative days, one patient met both thresholds, while 50% were category III-IV. Mean brake reaction time was 0.87 ± 0.40 seconds at 26-75 days and 0.77 ± 0.22 seconds at 76-125 days, while mean maximum brake force was 333.1 ± 136.9 N and 352.6 ± 110.0 N, respectively.At >125 days postoperatively, a majority of testing observations met both thresholds, with 62.5%, 12.5%, 20.8%, and 4.2% falling into categories I, II, III, and IV, respectively. CONCLUSIONS: Patients with right femoral fractures generally did not meet the predefined simulator braking time thresholds in the first 25 days postoperatively, whereas a majority first met both thresholds after 125 days. Simulator-based assessment may help guide individualized postoperative counseling. LEVEL OF EVIDENCE: Level II.