Minimum two-year follow-up of a reverse total shoulder arthroplasty using a wedged baseplate

Background Avoiding inclination of the glenoid baseplate in reverse shoulder arthroplasty often requires considerable glenoid reaming. It is proposed that the use of a metal wedged baseplate in all patients can achieve neutral inclination with reduced glenoid reaming. Materials and Methods A prospective clinical single-centre study with minimum two-year follow-up was carried out. Glenoid deformity was classified on CT and surgery planned using BluePrintTM. The Tornier Perform (R) Reversed Wedged Augmented Glenoid was used in all cases. Clinical outcome scores and radiographs were assessed. Results Seventy-three patients, mean age 76.6 years. Twenty-eight demonstrated no glenoid deformity and 19 demonstrated marked retroversion. Seventy completed two-year follow-up. Mean pain scores fell from 6 to 0.7. All Patient Reported Outcome Meaures (PROMS) were significantly improved. Active elevation increased by 62 degrees and external rotation by 28.7 degrees (p < 0.001). In patients with no glenoid wear (E0/A1), correction of inferior inclination was achievable with a 15 degrees full-wedge baseplate in all cases, reducing the reaming depth by 4.4 mm (p < 0.001). In patients with severe glenoid wear, a 35 degrees half wedge baseplate was often necessary to correct the deformity. The most common complications were stress reactions/fractures. Conclusion A metal wedged baseplate can achieve neutral inclination in all patients, minimising bone reaming and preserving lateralisation with good two-year outcomes. Level of evidence IV (case series with no comparison group).