Which of the following best defines joint instability post-TSA?

Joint instability following Total Shoulder Arthroplasty (TSA) is characterized primarily by frequent dislocations or subluxations. This indicates that the components of the shoulder joint are not properly aligned or secured, leading to a failure of the joint to maintain its normal position during movement. Dislocations refer to the complete displacement of the joint surfaces, while subluxations involve partial displacements, both resulting in significant functional impairment and discomfort.

In the context of TSA, achieving stability is a key goal of the procedure, as instability can severely limit the patient's functional outcomes and overall satisfaction. Other potential signs or symptoms associated with joint instability, such as pain or limited motion, do not define the instability itself but rather its consequences or associated conditions. Thus, recognizing frequent dislocations or subluxations as the hallmark of joint instability is crucial for understanding the complications that can arise postoperatively.