Exploring the prevalence and impact of hip and knee pain in pulmonary rehabilitation: a propensity-matched cohort study

Background: Musculoskeletal pain is more common in individuals with chronic respiratory diseases than the aged-matched general population. This investigation aimed to understand the prevalence and impact of hip and knee pain on pulmonary rehabilitation outcomes and completion rates.

Methods: Participants who experienced hip/knee pain in the 4 weeks prior to pulmonary rehabilitation completed an Oxford Hip and/or Knee Score alongside a routine pulmonary rehabilitation assessment. Participants engaged in a twice-weekly, 6-week outpatient pulmonary rehabilitation programme. A 1:1 propensity score match for age, sex, BMI, sessions attended and MRC score was completed prior to group comparison for a pulmonary rehabilitation cohort without hip/knee pain.

Results: 6.5% (n = 97) of pulmonary rehabilitation participants reported pain: hip (n = 27), knee (n = 40) or hip and knee pain (n = 30). 75 participants with hip/knee pain provided sufficient data for pre pulmonary rehabilitation matching and were propensity matched with a pulmonary rehabilitation group without hip/knee pain. The average Oxford Score across all reported joints was 28.7 (8.5) indicating moderate/severe pain at baseline. Statistically significant improvements were made in Oxford Scores for the left hip, left knee and right knee (P < 0.01) but not the right hip following pulmonary rehabilitation. There was no statistically significant difference between groups for improvements in quadriceps strength, walking tests or depression scores, both groups achieved within group significance. There were no significant differences in pulmonary rehabilitation completion rates between groups.

Conclusions: Prevalence of hip/knee pain in individuals presenting to pulmonary rehabilitation is 6.5%. Pain improved in the majority of joints following pulmonary rehabilitation and pain did not impact the effectiveness or completion of the programme.

Trial registration: This trial was an evaluation of a clinical service and has not been registered in a public domain.