Intermediate to long term results of stemless metaphyseal reverse shoulder arthroplasty: A five to nine year follow-up

Background: Shoulder arthroplasty incidence is increasing as is the volume of revision surgeries. Revision surgery is easier if humeral bone stock is preserved with minimal bone defects and osteolysis. This has led to an increased focus on the development of various short stemmed and stemless implants which provides stable fixation whilst preserving humeral bone stock.

Purpose: To review the medium to long term clinical and radiological outcomes, complications and survival rates of a stemless reverse shoulder prosthesis.

Patients and method: Patients with a minimum follow-up of 60 months following a reverse stemless shoulder arthroplasty were deemed eligible. Clinical and radiological data on twenty-one patients operated between 2009 and 2014 were recorded prospectively. Survivorship and patient recorded symptoms with the end point of revision surgery were recorded.

Results: Mean follow-up of 78 months (60-114 months). Mean range of active elevation was 136° (80-170°). Mean range of active abduction and active external rotation was 122° (70-170°) and 47° (10-75°) respectively. Mean Oxford score improved from 12 pre-operatively to 44 at final follow up (p < 0.0001). Mean Constant Murley Score improved from 18 to 72 (p < 0.0001). Mean ADLEIR score of 13 pre-operatively increased to 32 post-operatively (p < 0.0001). Notching was seen in 23.5% of cases and no radiolucent areas were observed around the glenoid component. There were two cases of post traumatic peri-prosthetic fractures that were managed conservatively and one case of deep-seated infection that required a washout. The survivorship at the most recent follow-up was 100%.

Conclusion: The advantages of bone preservation with the stemless metaphyseal prosthesis combined with encouraging medium to long term clinical and radiological results are very promising, particularly with the improved post-operative patient satisfaction scores. This is the first study that reports the results with a minimum of 5 year follow-up and has the longest mean follow-up period.

Clinical relevance: The reverse stemless shoulder prosthesis is an effective and reliable option for elective shoulder arthroplasty.