NEER SHOULDER PROSTHESIS - OUTCOME ACCORDING TO THE SHOULDER DISEASE

The outcome of 80 glenohumeral arthroplasties with the Neer prosthesis in 77 patients with degenerative or inflammatory shoulder disease was evaluated after a mean follow-up of three years five months. The arth roplasties were performed because of intractable pain and functional d isability due to destruction of the glenohumeral joint. The postoperat ive rehabilitation program focused on full recovery of joint motion an d function in 65 cases and on joint stability with partial recovery of joint motion and function in 15 cases. According to the criteria deve loped by Neer, the outcome was excellent or satisfactory in 75% of cas es and unsatisfactory in 25%. Constant's scores adjusted for age and g ender varied widely across diagnostic categories, from a high of 76% i n centered glenohumeral osteoarthritis (n=40) to lows of 59% in rheuma toid arthritis (n=21) and 45% in post-traumatic osteoarthritis (n=10) or cuff tear osteoarthritis (n=9). At reevaluation, 70% of patients ha d little or no pain and 90% were satisfied with the outcome. The mean increase in flexion of the arm (39-degrees) was markedly influenced by the diagnosis. The increases in lateral rotation (mean 35-degrees) an d medial rotation (four vertebral levels) of the arm were especially a ppreciated by the patients as having a very beneficial effect on the a bility to perform everyday tasks. Complications included instability i n three cases (two anterior dislocations and one posterior dislocation ), glenoid component loosening in 11 cases (of which only four require d reoperation) and secondary rotator cuff tear in eight cases. Our res ults add to the existing evidence that nonconstrained shoulder implant s, such as the Neer prosthesis, are both safe and effective in allevia ting pain and improving joint function. They should be used in patient s with refractory pain, disability due to restrictions in external and medial rotation of the arm and roentgenographic evidence of glenohume ral joint space loss.