Effectiveness of Joint Mobilization Compared with Continuous Passive Motion on Pain, Range of Motion, and Functional Outcomes in Post-Operative Knee Stiffness: A Randomized Controlled Trial

Background: Stiffness of the knee following surgical procedures such as total knee replacement and ligament reconstruction is a frequently observed complication that can significantly delay recovery. It is commonly associated with persistent pain, reduced joint mobility, and difficulty performing routine activities. Objective: To evaluate and compare the effects of continuous passive motion combined with joint mobilization versus passive range of motion with joint mobilization on pain, knee range of motion, and functional status in individuals experiencing post-operative knee stiffness. Methodology: This randomized controlled trial was conducted at the Department of Physical Therapy and Rehabilitation, Hayatabad Medical Complex, Peshawar. Sixty post-operative knee stiffness patients aged 18–55 years were randomly assigned into two groups (n=30 each). Group A received continuous passive motion with joint mobilization, while Group B received passive range of motion with joint mobilization. Interventions were given three times weekly for eight weeks. Outcomes included a visual analogue scale for pain, goniometric knee range of motion, and the Knee Injury and Osteoarthritis Outcome Score for function, assessed at baseline and post-treatment. Paired t-tests were used for within-group analysis, and independent t-tests were used for between-group analysis. Results: Both groups improved significantly in pain, range of motion, and function (p<0.001). However, continuous passive motion with mobilization showed superior outcomes. Group A had lower post-treatment pain (3.1±0.9 vs 4.2±1.0), greater knee flexion (102.3°±12.1° vs 92.6°±10.8°), and smaller extension deficit (4.1°±2.0° vs 6.3°±2.4°). Knee Injury and Osteoarthritis Outcome scores were also higher in Group A (74.8±9.3 vs 66.5±8.8), indicating better functional recovery compared to Group B. Conclusion: Both continuous passive motion and passive range of motion with joint mobilization improved post-operative knee stiffness, but continuous passive motion produced greater reductions in pain and better gains in range of motion and function.