Shoulder proprioception in partial and full thickness supraspinatus tears

This study was planned to evaluate shoulder proprioception in partial and full-thickness supraspinatus tears which is frequently encountered in clinic. The study was conducted on 21 partial supraspinatus tears (53.7±12.7 years, 26.6±2.9 kg/m2), 20 full-thickness supraspinatus tears (57.2±5.6 years, 27.6±1.9 kg/m2) and 20 asymptomatic individuals without any shoulder problems (19.5±0.9 years, 22.7±3.2 kg/m2) as control group. The shoulder proprioception was assessed with an Isomed 2000 isokinetic dynamometer using an active position repeat test at 40° and 100° target angles during scapular planar elevation. The actual angular value and deviation from the target angle as absolute error were recorded as degree. At rest, night and activity during the test pain were evaluated with visual analogue scale. The American Shoulder and Elbow Surgeons (ASES) form was used to determine functional activity level of the tear shoulder. Kruskall Wallis and Mann-Whitney U test were used for comparison of groups for nonparametric data and One-way ANOVA tests were used for parametric data. Spearman correlation analysis was used to assess the relationship between active joint position sensation with pain and functional activity. At the end of the study, it was seen that absolute value of the active joint position sense decreased during the 40° and 100° elevation on the the individuals with partial and full-thickness supraspinatus tears compared to the control group (p<0.05). Similarly, active joint position sensation during the 40° and 100° elevation was decreased in the partial and full-thickness supraspinatus tearing of the contralateral shoulder compared to the asymptomatic group (p<0.05). Compared to the actual value of the active joint position sensation, it was found to be deficit in partial tear and tear on the contralateral side at 100 degrees elevation compared to the partial tear and asymptomatic group (p <0.05). Compared to the actual value of the active joint position sense, it was found to be deficit in fulthickness tears both tear and contralateral side at 100° degrees elevation compared to the partial tear and asymptomatic group (p <0.05). It was found a positive correlation between active joint position sense at 40° target angle and resting pain (p<0.05, r=0.31), night pain (p<0.001, r=0.37), activity pain (p<0.05, r=0.32) and pain during 40°elevation (p<0.001; r=0.48). Similarly, it was found a positive correlation between active joint position sense at 100° target angle and resting pain (p<0.001, r=0.47), night pain (p<0.05, r=0.35), activity pain (p<0.05, r=0.41) and pain during 40°elevation (p<0.001; r=0.50). There was no correlation between shoulder functional activity level and active joint position sensation (p>0.05). It was seen that individuals with partial and full-thickness supraspinatus tears in terms of absolute value had decreased active joint position sense in both affected and contralateral shoulders and proprioceptive deficit in both shoulders. In actual value, it was determined that the individuals who were ripping full-fold were affected both on the tear and contralateral side. As a result, this deficit recorded according to asymptomatic individuals has to be improved in rehabilitation programs. Considering that special treatment of the affected extremity was frequently performed in rehabilitation programs, contralateral training was considered not to be neglected. However, the reduction of pain are thought to contribute to the development of the proprioceptive sense because of the effect of pain on the joint position sense.