Evaluation of the results of closed kinetic chain exercises applied in the conservative treatment of patellofemoral pain syndrome by means of shear wave elastography: A randomized controlled trial.

Purpose: Non-selective closed kinetic chain exercises (NSKCE) and or selective closed kinetic chain exercises (SCKCE) has been shown to increase Vastus medialis obliquus (VMO) muscle power in patellofemoral pain syndrome (PFPS). However, the superiority of the exercises to each other has not been shown. This study aimed to evaluating the effects of different exercises on the stiffness of the VMO and vastus lateralis (VL) muscles, pain management, functional scores, and thigh circumferences.

Methods: One hundred 60 knees of 80 patients followed up in our outpatient clinic between December 2016 and February 2018 were included in the study. Patients were divided into two groups as 40 patients with single-sided PFPS (20 male and 20 female patients) and 40 healthy controls (20 male and 20 female patients). The patients in each group were divided into subgroups according to NSCKCE or SCKCE. VMO and VL muscles were measured by shear wave elastography (SWE) before and after a 6-weeks therapy.

Results: There was a significant decrease in Visual Analog Scale (VAS) score while a significant increase was found in Lysholm Knee Scale (LKS), however, no statistically difference was found between the two exercise groups in PFPS patients. The effect of both exercises on pain and functional improvement was similar.

Conclusion: Decrease in VAS scores, increase in LKS scores, increase in thigh circumference measurements, and increase in the stiffness of VMO and VL muscles were observed in both groups who received SCKCE and NSCKCE on PFPS patients.

Trial registration: Study registered at ClinicalTrials.gov (registration number: NCT05427357).

Design: Randomized controlled trial.