Table II.
Rates of instability according to (1) publication date (2010-2016 vs. 2017-2020), (2) revision status (primary vs. revision arthroplasty vs. failed ORIF PHF), and (3) center of rotation
| Studies included | Shoulders | Instability present | Rate, % | P value | |
|---|---|---|---|---|---|
| Year published | |||||
| 2010-2016 | 68 | 4638 | 165 | 3.6 | .18 |
| 2017-2020 | 69 | 4668 | 143 | 3.1 | — |
| Primary vs. revision | |||||
| Primary RSA | 86 | 6607 | 168 | 2.5 | <.001 vs. revision; .01 vs. ORIF |
| Revision arthroplasty | 37 | 1404 | 80 | 5.7 | .81 vs. ORIF |
| Failed ORIF PHF | 9 | 226 | 12 | 5.3 | — |
| Center of rotation | |||||
| Medialized | 88 | 4950 | 141 | 2.8 | .15 |
| Lateralized | 22 | 1065 | 22 | 2.1 | — |
ORIF, open reduction internal fixation; PHF, proximal humerus fracture; RSA, reverse shoulder arthroplasty.
Primary RSA had significantly lower instability rates compared to both revision and failed ORIF PHF.