The Effect of Radial Shockwave Therapy on Iliotibial Band Tendon Thickness, Pain and Knee Function in Runners with Iliotibial Band Syndrome: A Double-blind, Randomized Clinical Trial

Abstract Background: Iliotibial Band Syndrome (ITBS) is a common injury in runners, causing lateral knee pain and functional limitations. Radial Shockwave Therapy (RSWT) is a non-invasive method used to reduce pain and promote tissue healing. However, its effects on iliotibial band (ITB) thickness and knee function in athletes remain unclear. Objective: To evaluate the effects of RSWT on ITB tendon thickness, pain intensity, and knee function in runners with ITBS. Design: Double-blind, sham-controlled, parallel-group randomized clinical trial. Setting: Physiotherapy clinics. Participants: Thirty-two field and track runners (weekly mileage: 20–40 km) with chronic ITBS (15 females, 17 males; aged 18–35) were randomly assigned using block randomization to either an active RSWT group or a sham control group Interventions: The RSWT group received increasing energy pulses to the lateral femoral epicondyle without anesthesia. Both groups underwent a standardized electrotherapy program including infrared, ultrasound, and transcutaneous electrical nerve stimulation, administered three times weekly for four weeks. Main Outcome Measures: Pain was assessed using the Visual Analog Scale (VAS), knee function via the Knee Injury and Osteoarthritis Outcome Score (KOOS), and ITB thickness through ultrasonographic imaging. Assessments were conducted at baseline, post-intervention, and one-month follow-up. Results: Significant time × group interactions were found for pain (VAS), knee function (KOOS), and ITB tendon thickness. The SWT group showed greater improvements than the sham-group across all outcomes. Pain scores decreased substantially (F(2,60) = 126.83, p < .001, partial η² = 0.81), indicating a very large effect size. KOOS scores improved significantly (F(2,60) = 75.59, p < .001, partial η² = 0.76), also reflecting a very large effect. ITB thickness was reduced (F(2,60) = 54.39, p < .001, partial η² = 0.65), demonstrating a large effect size. Conclusion RSWT enhances recovery in ITBS when combined with physiotherapy, offering measurable benefits in pain reduction and knee function.