The effect of subacromial pain on proprioception
It has been proven that proprioception is diminished in patients with pathologic shoulder conditions, but to date it remains unclear exactly why this is the case. A recent study has found that joint position sense does not change, but that the threshold for movement detection in fact decreases in healthy subjects in which subacromial pain is experimentally induced.
Stability in the glenohumeral joint depends to a large degree on neuromuscular control: sensory and proprioceptive information from the capsuloligamentous complex, surrounding muscles and skin is used to coordinate dynamic muscle activation. Proprioception has been shown to decrease in pathologic shoulder conditions – nevertheless, it is still unclear which underlying mechanism is responsible for this.
Subacromial pain was experimentally induced in twenty healthy subjects. Measures of joint position sense (passive joint replication, PJR) and movement detection threshold (threshold to detection of passive movement direction, TTDMD) were taken in three conditions: 1) baseline control; 2) experimental pain; and 3) recovery control.
In the subacromial pain condition, joint position sense was similar to the control conditions – the movement detection threshold however, was lower when shoulder pain was induced. This indicates the presence of a central protective mechanism that allows possibly harmful to be avoided. This also implicates that diminished proprioception in patients with shoulder pain might be due to tissue damage rather than pain alone.
Do you assess proprioception in patients with shoulder pain? Why (not)?
> From: Sole et al., Man Ther 20 (2015) 166-170. All rights reserved to Elsevier Ltd. Click here for the Pubmed summary.