The Effectiveness of Manual Therapy for Relieving Pain, Stiffness, and Dysfunction in Knee Osteoarthritis: A Systematic Review and Meta-Analysis

Background: Knee osteoarthritis (KOA) is the most common form of arthritis, leading to pain disability in seniors and increased health care utilization. Manual therapy is one widely used physical treatment for KOA. Objective: To evaluate the effectiveness and adverse events (AEs) of manual therapy compared to other treatments for relieving pain, stiffness, and physical dysfunction in patients with KOA. Study Design: A systematic review and meta-analysis of manual therapy for KOA. Methods: We searched PubMed, EMBASE, the Cochrane Library, and Chinese databases for relevant randomized controlled trials (RCTs) of manual therapy for patients with KOA from the inception to October 2015 without language restrictions. RCTs compared manual therapy to the placebo or other interventional control with an appropriate description of randomization. Two reviewers independently conducted the search results identification, data extraction, and methodological quality assessment. The methodological quality was assessed by PEDro scale. Pooled data was expressed as standard mean difference (SMD), with 95% confident intervals (CIs) in a random effects model. The meta-analysis of manual therapy for KOA on pain, stiffness, and physical function were conducted. Results: Fourteen studies involving 841 KOA participants compared to other treatments were included. The methodological quality of most included RCTs was poor. The mean PEDro scale score was 6.6. The meta-analyses results showed that manual therapy had statistically significant effects on relieving pain (standardized mean difference, SMD = -0.61, 95% CI -0.95 to -0.28, P = 76%), stiffness (SMD = -0.58, 95% CI -0.95 to -0.21, P = 81%), improving physical function (SMD = -0.49, 95% CI -0.76 to -0.22, P = 65%), and total score (SMD = -0.56, 95% CI -0.78 to -0.35, P = 50%). But in the subgroups, manual therapy did not show significant improvements on stiffness and physical function when treatment duration was less than 4 weeks. And the long-term information for manual therapy was insufficient. Limitations: The limitations of this systematic review include the paucity of literature and inevitable heterogeneity between included studies. Conclusion: The preliminary evidence from our study suggests that manual therapy might be effective and safe for improving pain, stiffness, and physical function in KOA patients and could be treated as complementary and alternative options. However, the evidence may be limited by potential bias an