Abstract
Shoulder apprehension is more complex than a pure mechanical problem of the shoulder, creating a scar at the brain level that prevents the performance of specific movements. Surgery corrects for shoulder instability at the physical level, but a re-dislocation within the first year is rather common. Predicting which patient will be likely to have re-dislocation is therefore crucial. We hypothesized that the assessment of neural activity at baseline and follow-up is the key factor to predict the post-operatory outcome. 13 patients with shoulder apprehension (30.03 ± 7.64 years) underwent clinical and fMRI examination before and one year after surgery for shoulder dislocation contrasting apprehension cue videos and control videos. Data analyses included task-related general linear model (GLM) and correlations imaging results with clinical scores. Clinical examination showed decreased pain and increased shoulder functions for post-op vs. pre-op. Coherently, GLM results show decreased activation of the left pre-motor cortex for post-surgery vs. pre-surgery. Right-frontal pole and right-occipital cortex activity predicts good recovery of shoulder function measured by STT. Our findings demonstrate that beside physical changes, changes at the brain level also occur one year after surgery. In particular, decreased activity in pre-motor and orbito-frontal cortex is key factor for a successful post-operatory outcome.
Highlights
Combining modern advances in functional neuroimaging and shoulder surgery has highlighted and defined the complex neural mechanisms behind shoulder apprehension in patients with glenohumeral instability
In particular an increased shoulder performance was found for Rowe, Simple Shoulder Test (SST), Subjective Shoulder Value (SSV) and Western Ontario Shoulder Instability (WOSI), while decreased pain levels was found for pain Visual Analog Scale (Fig. 1)
Our findings suggest that after seeing potential apprehension situations, the right–frontal pole (RFP) does a fast evaluation of the shoulder function and it decides if the movement can be performed or if pain sensations have to be elicited[2]
Summary
Combining modern advances in functional neuroimaging and shoulder surgery has highlighted and defined the complex neural mechanisms behind shoulder apprehension in patients with glenohumeral instability. Recent works have proven that this previously presumed peripheral pathology induces significant cerebral alterations, the complexity of which cannot be comprehensively measured by clinical scores[1, 2]. These results are based on a single observation in a preoperative cohort of unstable patients. The aim of the present study was to compare the cerebral mapping of shoulder apprehension in patients with glenohumeral instability before and one year after surgical stabilization and correlate them with clinical scores. They represented activities potentially triggering apprehension, such as putting the right shoulder at risk for antero-inferior dislocation or arming the shoulder with a javelin, quickly reaching backwards for a seatbelt, and so forth (created by C.G.)[2]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
