acromion

Impingement syndrome occurs when the rotator cuff tendons become "impinged" between boney anatomical structures of the shoulder, i.e. the coracoid as well as the acromion.

The Tour's medical service described the injury as a right shoulder trauma and a "dislocation between the collarbone and the acromion".

The scapula of the horse has no acromion process, but it is easy, if we compare the human scapula, to judge of the position which this process would occupy if it were present.

The ribs remarkably expanded and flattened; the scapula low and broad, with completely developed acromion and coracoid processes.

The deltoid is usually atrophied, allowing the acromion, coracoid, and great tuberosity of the humerus to stand out prominently beneath the skin.