title: Effects of Right Lower Limb Orthopedic Immobilization on Braking Function: An On-The-Road Experimental Study With Healthy Volunteers.
abstract: Little is known about how immobilization of the right lower limb might affect driving. The purpose of the present study was to evaluate the effect of 2 types of immobilization on the emergency braking time of healthy subjects during actual driving conditions. The emergency braking times of 14 healthy volunteers were assessed in a closed circuit under 3 conditions: wearing running shoes, wearing an Aircast Walker(®), or wearing a walking cast on their right lower limb. An instrumented car was used to measure the emergency braking times during braking tests with and without a distractor. The foot movement times were significantly increased with both immobilization devices compared with the running shoe (p < .01). The median total braking time with the running shoe during emergency braking without a distractor was 0.452 (interquartile range, 25th to 75th [IQR], 0.413 to 0.472) second. The results obtained with the Aircast Walker(®) or the walking cast were significantly longer (p < .01), at 0.480 (IQR, 0.431 to 0.537) second and 0.512 (IQR, 0.451 to 0.535) second, respectively. When a distractor was added, the total braking time with the running shoe, Aircast Walker(®), and walking cast was 0.489 (IQR, 0.429 to 0.575), 0.516 (IQR, 0.459 to 0.586), and 0.510 (IQR, 0.469 to 0.570) second, respectively, with no statistically significant differences among these 3 conditions. Wearing an immobilization device on the right lower limb minimally lengthens the emergency braking time in healthy drivers under actual driving conditions. Clinicians must nonetheless exercise caution when advising a driver wearing an orthopedic immobilization, because driving a motor vehicle is a complex psychomotor task that goes well beyond the emergency braking time.
authors.affiliation: Research Student, Division of Orthopaedic Surgery, Department of Surgery, Centre Hospitalier Universitaire de Sherbrooke (CHUS), Sherbrooke, QC, Canada.
authors.forename: Jean-Christophe
authors.initials: JC
authors.lastname: Murray
authors.affiliation: Orthopaedic Resident, Division of Orthopaedic Surgery, Department of Surgery, Centre Hospitalier Universitaire de Sherbrooke (CHUS), Sherbrooke, QC, Canada.
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Tremblay
authors.affiliation: Researcher, Research Centre on Aging, Institut Universitaire de Geriatrie de Sherbrooke (IUGS), Sherbrooke, QC, Canada.
authors.forename: Hélène
authors.initials: H
authors.lastname: Corriveau
authors.affiliation: Biomedical Engineer, Research Centre on Aging, Institut Universitaire de Geriatrie de Sherbrooke (IUGS), Sherbrooke, QC, Canada.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Hamel
authors.affiliation: Orthopaedic Surgeon and Titular Professor, Division of Orthopaedic Surgery, Department of Surgery, Centre Hospitalier Universitaire de Sherbrooke (CHUS), Sherbrooke, QC, Canada. Electronic address: Francois.Cabana@USherbrooke.ca.
authors.forename: François
authors.initials: F
authors.lastname: Cabana
mesh_terms: D000328:Adult; D001334:Automobile Driving; D002370:Casts, Surgical; D061826:Foot Orthoses; D064368:Healthy Volunteers; D006801:Humans; D007103:Immobilization; D008875:Middle Aged; D009068:Movement; D013997:Time Factors
keywords: automobile driving; cast; orthotic devices; reaction time; task performance analysis