Ankle fractures: When can I drive, doctor? A simulation study

Traumatic ankle fractures are common injuries. Following injury, patients ask their doctor 'when can I drive doctor?' The ability to safely drive depends on several variables including reaction time, force, range of movement and pain. Return of the braking force is essential for return to driving and to our knowledge has not been addressed previously in the literature. The aim of this study is to pilot a sample of patients with ankle fractures for the return of their normal power and visual reaction time following injury using a simulator (DTS: Drive Test Station). Normal parameters were defined by the patient's contra-lateral non-injured limb. After confirming fracture union, 12 drivers with an isolated right ankle fracture were recruited 7.8 days after coming out of plaster (0-21 days). DTS was used to examine patients' ability to apply a braking force of 35 kg, representing the amount of force required to do an emergency stop at 70 mph. Visual reaction time was tested to assess patients' cognitive function. Results showed the average maximum brake pedal force to be 34.4 kg (range: 32-35 kg). Paired sample t-test for the total visual reaction time and visual pathway reaction time showed the p-value>0.05 indicating no statistical difference between the injured limb and non-injured control side at the time of the examination. In conclusion, the DTS can be used to simulate an emergency stop to assess the motor power and cognitive function (visual reaction time) in case of right ankle fractures as this can give the patient an idea regarding their ability to apply brake force and the return of their visual reaction time. It is a practical assessment tool that could be used in fracture clinic setting. We still reserve our ability to advise patients to return to driving as this could bear significant medicolegal responsibility.