In a comparative study, mid-term findings after posttraumatic and degenerative hemi-prosthetic shoulder joint replacement were analyzed and compared with current reports in the literature.
The patient sample in the retrospective study consisted of 20 patients with proximal fractures of the humeral head (x = 64 years) and 6 patients (x = 61 years) with degenerative shoulder joint disease. In 14 patients the humeral head was replaced as a primary procedure at < 4 weeks after the trauma and in 6 patients as a secondary treatment at > 4 weeks. The follow-up period was 38-41 months on average. Evaluation was based on the Constant Score, subjective assessment by the patient, and conventional radiographs.
After posttraumatic shoulder replacement, the patients achieved a Constant Score of 65 (+/- 19) and after degenerative replacement 74 (+/- 34) points. In the posttraumatic group, the Constant Score after primary implantation was better than after secondary implantation (68 +/- 16 versus 59 +/- 15 points). After posttraumatic replacement, the only improvement over time was in pain levels (p < 0.05). 92% of all patients were satisfied with the result and would accept the same treatment again. Radiologically, a clinical correlate could be found for the arrosions at the acromion and occasionally for the secondary upwards displacement of the humerus. The results correlated well with data from the literature.
For posttraumatic conditions, hemiarthroplasty led to better results within four weeks and seemed to be a suitable alternative to other procedures, especially in older patients. Patients with primary osteoarthritis and idiopathic humeral head necrosis can expect good to excellent results after hemiarthroplasty. In both groups, the overall results depend mainly upon patient compliance and the state of the rotator cuff.