The Acute Facilitation Effects of General and Local, Muscular-Articular Interventions in Physical Therapy on Shoulder Proprioception
Özet
Various exercise interventions applied as a course lasting for several weeks have been reported to be effective on improving proprioception. The underlying causes are only hypothesized about. This study aimed to investigate the acute effects of one time intervention derived from different aspects of exercises on shoulder proprioception of healthy subjects. Both the magnitude and the duration of effect were aimed to measured. 55 female and 50 male, a total of 105 sedentary healthy subjects aged between 19 and 37 years old, were randomly divided into 6 intervention and a control group (n=15). The groups were: Active Movement Group (active movement at predetermined speed), Passive Movement Group (passive movements), Manual Therapy Group (joint play of glenohumeral joint), Stabilization Group (shoulder stabilization exercises), Plyometric Exercise Group (shoulder plyometrics) and General Warm Up Group (warm up through jogging). Each group received single intervention. Shoulder proprioception has been assessed as Joint position sense, and kinesthesia using original proprioception testing device version 2.0. Dominant shoulder at 70% internal rotation, 90% external rotation and 50% of ROM were measured in sitting position on first day, pre, post, 30 minute, 1 hour and 1 day post interventions. Increased variability of proprioception in control group necessitated use of baseline proprioception values of all 105 subjects as comparison reference. In active movement group there was a decrease in kinesthetic sense compared to baseline after intervention (p<0.05). Subjects in both passive movement and manual therapy group showed improvements in proprioception mainly at the extremes of ROM, either within group or against baseline (p<0.05). Single session of intervention was not sufficient to change proprioception in stabilization and plyometric groups (p>0.05). Inconclusive results were seen in warm up group (p>0.05). Additionally the direction of movement during testing of threshold to passive movement detection was found to affect proprioception measurements (p<0.05). Furthermore, kinesthesia testing might be more sensitive test for proprioception then joint position sense test. In conclusion, one time intervention might not be sufficient to significantly affect proprioception in healthy subjects. Although some improvements may be seen with passive exercises and manual therapy, cortical adaptation and learning rather than local stimulation of mechanoreceptors might be more critical to increase proprioception with the other exercises. Clinicians should be aware of possible decrease in proprioceptive acuity with repetitive active movements due to muscle fatigue.