Effects of lumbar spinal manipulation on pain and quadriceps strength in patellofemoral pain syndrome: A randomized controlled trial

Abstract

Background: Patellofemoral pain syndrome (PFPS) is a prevalent musculoskeletal condition associated with anterior knee pain and functional limitations. Conventional conservative approaches such as exercise and taping often provide inconsistent relief. Spinal manipulation, a manual therapy technique frequently used in complementary medicine, has demonstrated neurophysiological effects on pain modulation and motor control, but its application in PFPS remains underexplored.

Objective: This randomized controlled trial investigated the effects of lumbar spinal manipulation on pain and quadriceps strength in individuals with PFPS.

Methods: Thirty participants with clinically diagnosed PFPS were randomly allocated to a lumbar spinal manipulation group (n = 15) or a placebo group (n = 15). Interventions were administered twice weekly for four weeks. Outcome measures included pressure pain threshold, knee joint position sense, dynamic balance (Y-balance test), and quadriceps strength, assessed pre- and post-intervention. Paired and independent t-tests were used for within- and between-group comparisons (p < 0.05).

Results: Significant within-group improvements were observed in all outcomes except proprioception at 60° in the manipulation group, and in all but proprioception in the placebo group (p < 0.05). Compared to placebo, lumbar spinal manipulation resulted in significantly greater improvements in pain reduction and quadriceps muscle strength (p < 0.05). No significant between-group differences were noted in proprioception or dynamic balance.

Conclusion: Lumbar spinal manipulation appears to be an effective intervention for alleviating pain and enhancing quadriceps strength in patients with PFPS. Although its impact on proprioception and balance was limited, the findings support its clinical relevance in integrative management strategies for PFPS.

Trial registration: Korea Clinical Trial Registry (KCT0010483).

Keywords: Lumbar spinal manipulation; Pain modulation; Patellofemoral pain syndrome; Quadriceps strength; Randomized controlled trial.