The disabled throwing shoulder: spectrum of pathology-10-year update. [Part 1]
The term kinetic chain entails the manner in which the body meets the requirements of the overhead throwing motion most effectively; there are several sites at which deficits can occur that cause injury to the shoulder. An extensive evaluation of both shoulder as well as non-shoulder deficits contributing to the injury is necessary to identify the components that should be restored in order to achieve optimal functioning of the kinetic chain.
There has been a lot of research on the role of the scapula and effective methods of evaluation and specific effective rehabilitation protocols have been developed. It is however unclear whether the scapular position and dynamics are a causative factor or resultant with respect to injury and if identification and correction of dyskinesis is an adequate preventative measure to avoid injury.
Glenohumeral rotation is essential to overhead throwing. The condition known as a GIRD and a total range of motion deficit (TROMD) have been related to the onset of injury; both of these are dose and exposure dependent and can originate from the capsule and muscular structures. Specific intervention strategies include stretching, tissue mobilization and eccentric strengthening and endurance exercises – there is however still no consensus on the optimal composition. > From: Kibler et al., Arthroscopy 29 (2013) 141-161. All rights reserved to the Arthroscopy Association of North America.
The second part of this summary by Willem-Paul can be read on July 17.
The Pubmed summary of the article can be found here.
See the excessive external rotation / abduction stress on the shoulder joint during throwing in the slow motion YouTube clip below.