The Effect of Foot Orthoses on the Braking Response Time

The purpose of this study is to asses driving ability (brake response time) and the influence of two types of different foot orthoses after foot surgery.

Therefore we have two groups:

• Hallux valgus surgery (Chevron, Austin, SCARF, Akin etc.)
• Hallux valgus and additional forefoot surgery (Chevron, Austin, SCARF, Akin etc. and WEIL - Osteotomy, Peg-in-Hole, etc.)

BRT (brake response time) is assessed with commonly used right-sided hallux valgus shoes (HVS) and forefoot relief shoes (FRS). We measure the BRT at six different time points: one day before surgery without a foot orthosis (normal shoe)and with the orthoses (control run) (1) at two days (2), two weeks (3), four weeks (4) and six weeks (5) after the operation with a HVS and a FRS and eight weeks postoperative without a foot orthoses (6). The overall time frame is about nine weeks; each appointment for BRT measurement takes about fifteen to twenty minutes.

The BRT was assessed using a custom-made driving simulator as used in previously published studies. Participants were instructed to apply the brake pedal exclusively with the right foot as quickly as possible on a visual stimulus. The time interval until the subject operated the brake was measured 20 times, averaged and then taken as BRT value.

Inclusion criteria

• participants must have a valid driver´s license,
• used the right foot exclusively for accelerating and braking,
• free of any medical condition that could impair the ability to drive

Exclusion criteria

• taking medications that could affect reaction time (e.g. benzodiazepines and over-the-counter allergy and cold medications)
• had a history of alcohol or drug abuse,
• a central nervous system disorder such as epilepsy,
• a metabolic disorder,
• a psychiatric disorder,
• musculoskeletal disease,
• any visual acuity disorder (macular degeneration etc.; glasses allowed)