When Is It Safe for Joint Arthroplasty Patients to Resume Driving?

    Studies at the 2014 AAOS Annual Meeting addressed this common question from patients who have undergone hip and shoulder replacement.

    Driving after Total Hip Arthroplasty

    After hip replacement surgery, many patients are anxious to resume driving, and a new study challenges the conventional wisdom that patients should wait 6 weeks before getting back behind the wheel.

    Dr. Geoffrey Westrich, Director of Research, Adult Reconstruction and Joint Replacement at Hospital for Special Surgery in New York and one of the study authors, said that patients in the study were able to return to driving 4 weeks after total hip replacement, 2 weeks sooner than previously recommended. The study, “A Novel Assessment of Driving Reaction Time Following THR Using a New Fully Interactive Driving Simulator,” was presented at the annual meeting of the American Academy of Orthopaedic Surgeons.

    “One of the most common questions patients ask after hip replacement is when they can start driving again, and this is the first study of its kind to test their reaction time after the procedure,” said Dr. Westrich, who came up with the idea for the driving simulator while watching his children play video games.

    But the interactive simulator used in his study is more intricate than a Wii game. “It’s a very sophisticated machine made by a company that makes driving simulators for the automobile industry,” Dr. Westrich said.

    More than 330,000 hip replacements are performed in the United States each year. Patients exhibit decreased reaction time after the surgery, making it unsafe for them to drive in the immediate postoperative period. Most orthopaedic surgeons recommend that patients wait about 6 weeks before they resume driving, but many do not want to wait that long.

    “Over the past 5 or 10 years, we’ve seen advances such as minimally invasive hip replacement and newer implants that are advantageous to patients and may improve recovery time. Our study set out to obtain good, objective data to determine if it would be safe for people to return to driving sooner,” Dr. Westrich said.

    One hundred patients of three orthopedic surgeons at Hospital for Special Surgery were enrolled in the study to assess their driving reaction times using a fully-interactive driving simulator with an automatic brake reaction timer from the American Automobile Association.

    All participants had a total hip replacement on the right side, and all took the driving test prior to having surgery. They were then randomly selected to repeat the test 2, 3, or 4 weeks after hip replacement. Reaction time was measured by the computerized driving simulator.

    The reaction timer, equipped with an accelerator and brake pedal, simulates driving. Patients were instructed to place their foot on the accelerator, which activated a green light, and to keep their foot on the accelerator until a Stop sign appeared. When the Stop sign popped up, they were supposed to move their foot to the brake pedal. The amount of time it took for the subject to switch from the gas to the brake pedal was measured by the machine.

    The study defined a return to safe driving reaction time as a return to a reaction time that was either the same as or better than the preoperative driving reaction time. Observing reaction times at different intervals revealed that 2 and 3 weeks after surgery, patients had not yet made a full recovery to their respective baseline reaction time and generally were not ready to drive.

    However, at 4 weeks following hip replacement, patients had actually improved their reaction time compared to what it was before the surgery and therefore could be cleared to drive. It was also observed that patients under the age of 70 reached an improved reaction time earlier than those over 70.

    “By using a standardized, driving simulator to measure reaction times, our study will be reproducible and we can apply our model to other surgical procedures that may affect one’s ability to drive safely postoperatively,” Dr. Westrich noted.

    He will soon begin enrolling patients in another study to determine when it is safe to drive after total knee replacement.

    Driving after Total Shoulder Arthroplasty Surgery

    More than 53,000 Americans have total shoulder arthroplasty (TSA) surgery each year. But as noted by Joseph Zuckerman, MD, Chairman of the Department of Orthopaedic Surgery at NYU Langone Medical Center in New York, the effects of this surgery on a patient’s ability to safely drive a vehicle, and the appropriate recovery time before patients should return to driving, have yet to be determined

    Dr. Zuckerman is the senior author of a new study, “Driving Performance after Total Shoulder Arthroplasty,” which tested the driving skills of 28 TSA patients, with a mean age of 65 ±10 years, at four distinct time points using a driving simulator:

    • Preoperatively
    • 2 weeks after surgery
    • 4 weeks after surgery
    • 12 weeks after surgery

    The study was presented recently at the annual meeting of the American Academy of Orthopaedic Surgeons.

    Using a validated driving simulator, the study authors recorded the number of total simulator collisions, off-road collisions, on-road collisions, center-line crosses, and off-road excursions at each time point. Pain Visual Analog Scale (VAS) and Shoulder Pain and Disability Index (SPADI) scores also were documented, in addition to annual driving mileage and hours slept the previous night.

    In 28 patients, the mean number of collisions decreased from 6.2 during the first test (presurgery) to 5.9 at the second test (2 weeks after surgery), and from 5.2 during the third test to 4.2 by the fourth and final test. There was a statistically significant difference in the mean number of collisions between the first and fourth test.

    Also, patients who drove less than 1,800 miles per year incurred a greater number of collisions at the first and fourth tests, compared with patients who drove more than 8,700 miles per year. “At risk driving behavior,” quantified as the number of center-line crosses, decreased from 20.6 during the first test to 14.8 by the fourth test. 

    According to the study authors, patients showed improved driving performance at 12 weeks, with a significant decrease in the number of collisions in the simulated driving course compared with the tests conducted preoperatively and 2 weeks after surgery – which suggests, Dr. Zuckerman said, that drivers with severe osteoarthritis of the shoulder may be impaired drivers prior to surgery.

    The study authors recommend that patients wait at least 6 weeks, and optimally 12 weeks, to resume driving following shoulder replacement surgery. Research on driving performanmce after TSA is ongoing, Dr. Zuckerman said.