Effects of Isotonic Strength Training with and Without Electrical Muscle Stimulation in Patients with Knee Osteoarthritis

Abstract

Background: Knee osteoarthritis is a common degenerative joint disorder associated with pain, quadriceps weakness, and functional limitation, and exercise-based rehabilitation remains a principal component of conservative management. Electrical muscle stimulation is frequently used as an adjunct to improve muscle activation, but its short-term additive value when combined with isotonic strengthening remains uncertain. Objective: To compare the short-term effectiveness of isotonic quadriceps strength training with and without electrical muscle stimulation in patients with knee osteoarthritis. Methods: This experimental pretest-posttest randomized clinical study was conducted in a physiotherapy outpatient department and included 35 patients aged 40 to 65 years with unilateral knee osteoarthritis. Group A (n=18) received isotonic quadriceps strengthening alone, while Group B (n=17) received electrical muscle stimulation followed by the same strengthening protocol. Treatment was delivered three times per week on alternate days for one week. Pain was assessed using the Visual Analogue Scale, and functional status was evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index. Independent and paired t-tests were applied using SPSS version 20. Results: Both groups improved after intervention, but not statistically significant between-group difference was found for WOMAC (p=0.887) or VAS (p=0.109). Conclusion: Isotonic quadriceps strengthening with and without electrical muscle stimulation demonstrated comparable short-term effectiveness in reducing pain and improving function in patients with knee osteoarthritis, and the addition of electrical muscle stimulation did not show superior benefit over exercise alone during the study period.