A hemiarthroplasty is a partial shoulder replacement where only the humeral head (ball of the joint) is resurfaced or a replaced. The glenoid is not replaced or resurfaced and thus it is essential that the glenoid is in a relatively healthy state if a hemiarthroplasty is being considered. The operation is performed for conditions where the humeral head is worn or damaged such as osteonecrosis (bone death), large Hill-Sachs lesion (a defect in the head resulting from the impact of a dislocation) or fracture. When performed for arthritic joints, a hemiarthroplasty may not provide as good pain relief as a total shoulder replacement.

A shoulder resurfacing is a procedure where either one or both surfaces of the joint are resurfaced. If only the ball of the joint is resurfaced, the procedure is referred to as a Humeral head resurfacing or hemiresurfacing. If both surfaces of the joint are resurfaced, the procedure is called a total shoulder resurfacing. A hemiresurfacing is appropriate in conditions where only the ball of the joint is damaged such as osteonecrosis. A total resurfacing is performed most commonly for arthritis where both sides of the joint are worn or damaged.

A Total shoulder replacement is a complete shoulder replacement where both sides of the joint are replaced or resurfaced. A prosthetic glenoid component is fixed to the shoulder blade and the humeral head is resurfaced or replaced. The operation is performed most commonly for arthritis where both sides of the joint are worn or damaged. 

A bone conserving shoulder replacement is one where a minimal amount of native bone is removed prior to implanting the prosthetic components and thereby conserves more bone. As the technology of shoulder replacements has improved, the operation is being increasingly considered in relatively younger individuals with damaged joints.  Shoulder replacements, like most other joint replacements, have a limited life span as the artificial bearings wear out over time and may need to be revised or exchanged later on in life. In such instances revision surgery is more likely to be feasible if the bone stock around the joint is reasonably preserved. 

On average a shoulder replacement would be expected to offer good function for at least 10 years, provided that the soft tissues such as the muscles and tendons around the joint are healthy. Shoulder replacements, like most other joint replacements, will demonstrate signs of wear or loosening over time, which in turn may lead to symptoms such as pain or deterioration of function. It is not uncommon for the tendons around the joint (the rotator cuff) to wear out and fail over time and this is turn may lead to deterioration of function.