The HAPI 'Hip Arthroscopy Pre-habilitation Intervention' study: does pre-habilitation affect outcomes in patients undergoing hip arthroscopy for femoro-acetabular impingement?

The purpose of this randomized prospective comparative controlled pilot study was to determine whether specific patient exercises done pre-hip arthroscopy surgery for femoro-acetabular impingement affected post-operative recovery. Between October 2013 and June 2014, 6 males and twelve females over the age of eighteen, who were listed for hip arthroscopy for femoro-acetabular impingement, were randomized into two groups. A hip-specific, 8-week home exercise programme was given to the experimental group before their surgery. The control group was given no instruction on exercise before surgery. All participants followed the same rehabilitation programme after surgery. Outcome measures were assessed at set time intervals. Hand held dynamometry was used to assess muscle strength, and the EQ-5D-5 L Score and the Non-Arthritic Hip Score were utilized. Sixteen participants completed the study (eight controls: mean age 41.75 years and eight intervention: mean age 37.5 years). A mixed ANCOVA analysis compared the treatment groups taking baseline values into account. A statistically significant difference was found between the treatment groups for knee extension strength on both operative (P = 0.05) and non-operative sides (P = 0.002), hip flexor strength operative side (P = 0.02) and for EQ-5D-5 L health (P = 0.03), in favour of the intervention group. There was no significant difference between the treatment groups for the other measures, although some tended towards significance. This small pilot study has been designed to aid the further research and the differences between the groups found in these results may inform future larger scale studies.