THE EFFECT OF SINGLE-STAGE PERTURBATION EXERCISE ON THE SHOULDER JOINT POSITION SENSE AND TRAPEZIUS MUSCLE ACTIVATION IN PATIENTS WITH ARTHROSCOPIC ROTATOR CUFF REPAIR

Abstract

Objective: Perturbation exercises conducted on mobile surfaces in the latter period of the rehabilitation increase the neuromuscular control. The purpose of the study was to investigate the effects of single session perturbation exercises’ on active joint position sense and on the electromyography activation of the trapezius muscle in patients who underwent arthroscopic rotator cuff repair in the previous 6 months.
 Method: 12 individuals who underwent arthroscopic rotator cuff repair were included in the study as the study group (age: 54.83±3.5), and 13 individuals with in an asymptomatic shoulder joint were included as the control group (age: 49.07±4.5). All subjects were evaluated before and after single-session perturbation exercise. Active joint position sense at 90° shoulder flexion and abduction was assessed using a laser pointer-assisted angle reproduction test. The activation of the trapezius muscles during this test was recorded by the superficial electromyography tool. The pre-exercise and post-exercise values were analyzed using an in-group Wilcoxon signed-rank test. The Mann–Whitney U test was used for group comparisons.
 Results: There was no difference between groups in the active angle reproduction test before and after the perturbation exercise (flexion p:0.124; abduction p:0.421). When electromyography activations after the exercise were compared, the activation of the operated upper trapezius (p:0.01) and the non-operated lower trapezius decreased (p:0.024). There was no correlation between the electromyography activation of the trapezius muscle and active joint position sense (flexion p:0.657; abduction p:0.662).