Patellofemoral pain: One year results of a randomized trial comparing hip exercise, knee exercise, or free activity

Abstract

Objective Extended follow‐up of a randomized trial comparing hip‐focused exercise, knee‐focused exercise, and free physical activity in patellofemoral pain (PFP). Methods A single‐blind randomized controlled trial included 112 patients aged 16‐40 years (mean 27.6 years) with a clinical diagnosis of PFP ≥3 months (mean 39 months) and pain ≥3/10 on a Visual Analog Scale. Patients were randomized to a 6‐week exercise‐based intervention consisting of either isolated hip‐focused exercises (n = 39), traditional knee‐focused exercise (n = 37), or free physical activity (n = 36). All patients received the same patient education. The primary outcome measure was the Anterior Knee Pain Scale (AKPS, 0‐100). Secondary outcomes were usual and worst pain, Tampa Scale of Kinesiophobia, Knee Self‐Efficacy Score, Euro‐Qol (EQ‐5D‐5L), step‐down test, and isometric strength. Blinded observers assessed outcomes at baseline, 3, and 12 months. The study was designed to detect a difference in AKPS >10 at 12 months. Results After 1 year, there were no significant between‐group differences in any primary or secondary outcomes. Between‐group differences for AKPS were as follows: knee versus free physical activity −4.3 (95% CI −12.3 to 3.7); hip versus free physical activity −1.1 (95% CI −8.9 to 6.7); and hip versus Knee 3.2 (95% CI −4.6 to 11.0). The cohort as a whole improved significantly at 3 and 12 months compared to baseline for all measures except for knee extension strength. Conclusion After 1 year, there was no difference in effectiveness of knee exercise, hip exercise, or free physical activity, when combined with patient education in PFP.

Trunk, Hip and Knee Exercise Programs for Pain Relief, Functional Performance and Muscle Strength in Patellofemoral Pain: Systematic Review and Meta-Analysis

“…Changes in pain relief according to changes in the VAS were reported in sixteen studies, of which thirteen were rated as being of "good" quality 10,15,17,18,[28][29][30][31][32][33][34][35][36] and three as being of "fair" quality. 8,37,38 Although the meta-analysis was limited, as there were insufficient studies comparing hip-only or knee-only exercise with Control groups for pain relief, eleven studies examining Hip or Hip&Knee exercise programs compared with a knee-only exercise were eventually included in this meta-analysis (Figure 2).…”

“…Two included studies assessed functional changes with LEFS, 10,31 while eight studies used AKPS. 8,15,17,18,[32][33][34][35] Two additional studies used the WOMAC to assess functional changes, but were not included in the meta-analysis due to substantial discrepancy between intervention groups. 8,39 Both Hip only (SMD = 0.48 (0.08, 0.88); p = 0.02; I 2 = 71%) or Hip&Knee exercise programs (SMD = 1.28 (0.45, 2.12); p = 0.003; I 2 = 84%) proved to be superior to Knee 10 1…”

“…Hip abduction and external rotation strength were doubtlessly the most commonly reported outcomes, assessed in fourteen studies, 15,17,18,[30][31][32][33][35][36][37][38][39][40][41] of which eleven were included in the meta-analysis. Strength of the hip abduction was reported in eleven studies comparing hip-only or knee-only exercise programs and Control groups with no intervention.…”

“…Strength of the hip abduction was reported in eleven studies comparing hip-only or knee-only exercise programs and Control groups with no intervention. 15,17,18,[31][32][33][35][36][37][38][39] A significant increase in muscle strength was found across all intervention groups (SMD = 1.27 (0.86, 1.67); p < 0.05; I 2 = 67%). Hip exercise programs appeared to be superior (SMD = 1.50 (0.85, 2.15); p < 0.05; I 2 = 77%) to Knee exercise programs (SMD = 1.07 (0.68, 1.47); p < 0.05; I 2 = 27%), although surprisingly, regardless of the overall improvement, a significant difference in the effects between Hip exercise and Knee exercise was not found (p = 0.27).…”

“…Positive effects of the exercise programs targeting muscle groups adjacent to the knee have been reported by several authors, [12][13][14][15][16] although not all have shown to be effective. 17,18 More importantly, even with numerous studies conducted with the aim of comparing different exercise program for patients with PFP, it is still not clear which approach is the most effective. Such ambiguity can result in a more time-consuming clinical practice, as clinicians often prescribe traditional, knee-only exercise programs regardless of their actual effectiveness.…”