Low-dose strength training in addition to neuromuscular exercise and education in patients with knee osteoarthritis in secondary care - a randomized controlled trial

Abstract

Objectives: To investigate the effects of lower limb strength training in addition to neuromuscular exercise and education (ST + NEMEX-EDU) compared to neuromuscular exercise and education alone (NEMEX-EDU) on self-reported physical function in patients with knee osteoarthritis (KOA).

Design: Patient-blinded, parallel-group randomized controlled trial (RCT).

Methods: The trial included 90 patients in secondary care with radiographic and symptomatic KOA, ineligible for knee replacement. Both groups exercised twice weekly for 12 weeks. Additional strength training consisted of a single, fatiguing knee extension set (30-60RM) before four sets of leg-press (8-12RM). Primary outcome was the between-group difference on the subscale activities of daily living from the Knee Injury and Osteoarthritis Outcome Score (KOOS_ADL) at 12 weeks. Secondary outcomes included KOOS symptoms, pain, function in sport and recreation, and quality of life, 40 m walk, stair climb, leg extension power, EuroQol-5D-5L, pain medication usage, and adverse events.

Results: There was no statistically significant between-group difference in KOOS_ADL at 12-weeks; adjusted mean difference -1.15 (-6.78 to 4.48). Except for the stair climb test, which demonstrated an adjusted mean difference of 1.15 (0.09-2.21) in favor of ST + NEMEX-EDU, all other outcomes showed no statistically significant between-group differences. Neither group improved leg extension power.

Conclusion: The addition of lower-limb strength training, using a low-dose approach, to neuromuscular exercise and education carried no additional benefits on self-reported physical function or on most secondary outcomes. Both groups displayed similar improvements at 12-week follow-up. Hence, the current low-dose strength training approach provided no additional clinical value in this group of KOA patients. Trial identifier (ClinicalTrials.gov): NCT03215602.

Keywords: Exercise; Knee; Osteoarthritis; Self-reported; Strength training.