Reliability of pain scores during a body weight support protocol in individuals with knee osteoarthritis

To explore the reliability of percentage of Body Weight Support (BWS) needed for maximal pain relief and of pain scores across 12 walking conditions including pre and post-over-ground walking and an unweighting protocol from 0% to 40% BWS on a lower body positive pressure (LBPP) treadmill for individuals with knee osteoarthritis (OA).

Twenty individuals (64 ± 9.44 years) with knee OA completed over-ground walking and an unweighting protocol on an LBPP treadmill. The amount of BWS started at 0% and increased by 5% increments until it reached 40%. Pain scores were recorded at the end of each increment.

The reliability of pain scores was assessed using a Spearman's rho. This study found moderate reliability of the percentage of BWS for maximal pain relief. Additionally, there was good reliability of pain scores with pre and post-over-ground walking and from 0% BWS to 30% BWS, but moderate reliability of pain scores was found at 35% and 40% BWS.

This study supports the use of pain scores as a reliable measure during an unweighted walking session on an LBPP treadmill.IMPLICATIONS FOR REHABILITATIONBoth the OARSI and ACR recommend exercise in the treatment of individuals with knee OA but acknowledge that pain during exercise and exercise preference/accessibility are important when considering the type of exercise for an individual.LBPP treadmills decrease pain in individuals with knee OA during walking.Pain scores during unweighted walking show moderate to good reliability for individuals with knee OA.This study provides an unweighting protocol to use clinically to determine the Body Weight Support needed to decrease pain.