Final answer:
A deficiency of the glenohumeral ligaments along with a deficient rotator cuff is a contraindication to shoulder hemiarthroplasty because both structures are crucial for joint stability and support. Hemiarthroplasty requires healthy surrounding tissues to ensure the stability and proper function of the shoulder.
Step-by-step explanation:
The deficiency of the glenohumeral ligaments in combination with a deficient rotator cuff is a contraindication to shoulder hemiarthroplasty. The rotator cuff is a critical structure for shoulder stability and includes the tendons of the subscapularis, supraspinatus, infraspinatus, and teres minor muscles. These tendons connect the scapula to the humerus, forming a cuff around the shoulder joint.
The rotator cuff when intact and strong stabilizes the shoulder by holding the head of the humerus in the glenoid cavity of the scapula during motion. The glenohumeral ligaments are part of the capsule of the shoulder joint and provide support to the anterior side, reinforcing the stability of the joint. In the setting of a deficient rotator cuff these ligaments become even more important for maintaining the integrity of the shoulder joint. However if the glenohumeral ligaments are also deficient or compromised, the joint becomes significantly destabilized, making it inappropriate for shoulder hemiarthroplasty. This procedure relies on the surrounding soft tissues such as the rotator cuff and ligaments to provide stability to the new prosthetic joint component.