Metaphyseal Reverse Total Shoulder Arthroplasty - Long-Term Results With 5 - 11 Years Follow-Up

Aim: To evaluate the 5 -11 years long-term clinical and radiological outcomes using a short metaphyseal reverse total shoulder arthroplasty (rTSA) without a diaphyseal stem.

Background: rTSA are increasingly used in recent years. Metaphyseal humeral components without a stem were developed to minimise bone resection and preserve bone.

Methods: 185 consecutive shoulders underwent rTSA between 2005 to December 2011, 159 with stemless implant and 26 with stemmed implant.
Mean follow-up 89 months (7 years & 5 months) (range 60 - 138 months). There were 141 females and 44 males; Mean age at surgery 74.8y (range 38-93y). Aetiology: 108 cuff arthropathy, 22 fracture sequelae, 24 rheumatoid arthritis, 14 failed RC repair or massive irreparable cuff tear, 3 osteoarthritis with cuff deficiency or eroded glenoid, 8 failed anatomical prosthesis with cuff deficiency, and 6 for acute trauma. 14 patients underwent bilateral (staged) rTSA at that period.
50 patients were operated as revision arthroplasty.

Results: Patients’ satisfaction (SSV) improved from 0.8/10 to 8.2/10. Mean Constant Score (for all diagnoses) improved from 15.6±8.6 preop to 59.0±20.4 (Age/sex adjusted 86.8±30.3) at the last follow-up (p<0.0001). Mean active range of movement improved from 53° to 129.5° elevation, 10° to 50.6° active external rotation and 24° to 67.2° active internal rotation. Radiographic analysis showed no lucencies, subsidence or stress shielding around the humeral or glenoid components.
Glenoid notching was found in 38 patients (20.5%) (36 grade 1-2, 6 grade 3).

Conclusions: The short metaphyseal rTSA (without a diaphyseal stem) shows encouraging long-term results with excellent pain relief and shoulder function, restoration of good active range of motion and high patients’ satisfaction scores. The design of this implant seems to result in improved rotational movements, low incidence of glenoid notching and no implant loosening, subsidence or stress shielding.