A pilot study into the reliability of partial weight bearing

PWB is commonly taught by physiotherapists; the rationale is a reduced load through an affected limb, implemented at the appropriate time, will enhance stabilisation and bone healing, and reduce the risk of potential mal-alignment due to the decreased forces (Soloman et al, 2005). However, it remains unclear if subjects are consistent in effectively transmitting the advised load. A convenience sample (n = 13) from an adult student population. Exclusion criteria included lower limb injury, marked leg length discrepancy and spinal scoliosis. Participants were measured daily over three consecutive days using a Kistler force platform to record ground reaction force (GRF), fully weight bearing (FWB) and then partial weight bearing (PWB) 50% with elbow crutches demonstrating a three-point gait. Participants wore the same flat shoes on each occasion and received standardised instructions on crutch walking by the same researcher . Subjects mobilised at a comfortable speed as increasing ambulatory speed can directly increase GRF (Hurkmans et al, 2009). Three sets of data for both PWB and FWB were collected on each day for every participant; means and standard deviations were calculated. Statistical analysis was conducted using the intra class correlation co-efficient (ICC). Day 1: 393.77N (S.D.±165.49) Day 2: 361.17N (S.D.±188.40) Day 3: 344.04N (S.D. 184.82) Mean PMBing decreased by 8% on day 2, and by 13 % (still comparing with day 1) on day 3. The ICC was .924 demonstrating an excellent level of reliability overall. The overall level of reliability of PWB was excellent, but there was a tendency for the load to decrease progressively over the three day period