Modular total shoulder: early experience and impressions.

All design considerations in shoulder arthroplasty are based on reconstructing normal anatomy and enhancing prosthetic fixation, particularly on the glenoid side. These goals are further enhanced by meticulous attention to detail in placement of the component parts relative to the bony anatomy. In addition, great attention must be paid to management of the soft tissue tensions and placement of the component parts relative to soft tissue origins and insertions so that asymmetric overloading of the components can be avoided and loosening and wear can be minimized. The problem of management of prosthetic replacement with associated massive rotator cuff tears continues to be a dilemma. Use of an oversized humeral head articulating with the acromion can offer a compromise solution to the problem. This technique can be combined with altered glenoid component placement or reshaping of the bony glenoid to accommodate its altered relationship with the humeral articular surface. Future design changes are needed to deal with this complex problem.