Body weight support through a walking cane in inexperienced users with knee osteoarthritis

Abstract

Background: Walking canes are a self-management strategy recommended for people with knee osteoarthritis (OA) by clinical practice guidelines. Ensuring that an adequate amount of body-weight support (%BWS) is taken through the walking cane is important as this reduces measures of knee joint loading.

Research question: 1) How much body weight support do people with knee OA place through a cane? 2) Do measures of body weight support increase following a brief simple training session?

Methods: Seventeen individuals with knee pain who had not used a walking cane before were recruited. A standard-grip aluminum cane was then used for 1 week with limited manufacturer instructions. Following this, participants were evaluated using an instrumented force-measuring cane to assess body weight support (% total body weight) through the cane. Force data were recorded during a 430-metre walk undertaken twice; once before 10 min of cane training administered by a physiotherapist, and once immediately after training. Measures of BWS (peak force, average force, impulse equal to the average cane force times duration, and cane-ground contact duration) were extracted. Using bathroom scales, training aimed to take at least 10% body weight support through the cane.

Results: Before training, the average peak BWS was 7.2 ± 2.5% of total body weight. Following 10 min of training, there was a significant increase in average peak BWS by 28%, average BWS by 25%, and BWS impulse by 54% (p < 0.05). However, individual BWS responses to training were variable. Duration of cane placement increased by 22% after training (p = 0.02). Timing of peak BWS through the cane occurred at 51% of contact phase before training, and at 53% after training (p = 0.05).

Significance: A short training session can increase the transfer of body weight through a walking cane. However, more sophisticated feedback may be needed to achieve target levels of BWS.

Keywords: Biomechanics; Knee osteoarthritis; Training; Walking stick, physiotherapy.