Anatomic Study of the Coracoid Process: Safety Margin for Osteotomy for Shoulder Surgery

Abstract

Background: Surgical procedures as coracoid osteotomy, transfer, and fixation are used for management of recurrent anterior shoulder instability. However, the peculiar anatomy of bony and soft tissue footprints of the coracoid, as they relate to these surgical procedures, need further detailed studies owing to its clinical importance.Aim of the work: to obtain safety margin for osteotomy of the coracoid process. Materials and methods:The material of this work included twenty upper limbs of formalin preserved specimens obtained from the dissecting room of anatomy department, faculty of medicine, Alexandria University. Dimensions of the coracoid process were recorded. Anatomical measurements between the tip of the coracoid process to the anterior and posterior margins of the tendon of pectoralis minor were recorded. Distances between the tip of the coracoid process and the anterior and posterior margins of coracoacromial ligament, coracohumeral ligament, and the most distal point of conoid and trapezoid ligaments were recorded.Results: The mean length, width, and height of the coracoid were 4.25, 1.4, 1.16 cm respectively. The mean distance between the tip of the coracoid process to the anterior and posterior margins of pectoralis minor were 1.07 and 2.04 cm respectively. The mean distance between tip of coracoid process and coracoacromial ligament (anterior and posterior margins), coracohumeral, conoid and trapezoid ligaments were 1.32, 2.19, 1.11, 3.70 and 2.73 cm respectively. Conclusion:A safety margin of 2.35 cm from the tip of the coracoid process is recommended to avoid injury of coracoclavicular ligament. This distance was correlated with the distance between the tip and the posterior margin of pectoralis minor muscle.