Trabecular metal backed glenoids in anatomic total shoulder arthroplasty: outcomes after a decade on average

Background

First-generation trabecular metal (TM) backed glenoids reported poor implant survival and were recalled from the market. Second generation TM glenoids have demonstrated promising findings at short- and mid-term follow-up. In our study, we report on clinical and radiographic outcomes of TM glenoids with an average of 10 years of clinical and radiographic follow-up.

Methods

The charts of 14 TM glenoid patients with minimum 5 years follow-up were retrospectively analyzed. The primary end points included implant survival, range of motion, and patient-reported outcomes. Additionally, radiographic data (metal debris, lateral humeral offset (LHO), acromiohumeral interval (AHI)) were studied.

Results

The mean age at surgery was 52 ± 11 years and the mean follow-up time was 10 ± 3 years. Implant survivorship was 100%. Range of motion improved significantly following surgery. Forward elevation changed from 120 ± 22º preoperatively to 155 ± 13º postoperatively (P < .01). The mean external rotation showed a statistically significant increase from 19 ± 30º preoperatively to 54 ± 13º postoperatively (P < .01). Internal rotation improved six vertebral levels on average (P < .01). Pain levels decreased significantly from 7 ± 1 to 2 ± 2 (P < .01) while American Shoulder and Elbow Surgeons Shoulder scores increased from 35 ± 10 to 83 ± 21 (P < .01). Simple Shoulder Test scores demonstrated an improvement from 5 ± 3 to 10 ± 3 (P < .01). No patients had glenoid loosening, metal debris, or radioluency on radiographic imaging. The immediate LHO was 18 (standard deviation [SD] ± 9) and final LHO of 16 (SD ± 8) (P value = .01). The immediate AHI was 12 (SD ± 3) and final AHI was 11 (SD ± 3) (P value = .01).

Conclusion

TM backed glenoids should remain in the modern orthopedic surgeon’s armamentarium of procedures. This particular glenoid design showed 100% implant survival at a decade following surgery, and provided sustained improvements in range of motion and shoulder function in osteoarthritic patients.