were found by Wright et al (1.8%) and Worland et al (2.38%).10,11 In the study by Singh et al, 43 (36 humerus, 5 glenoid, 2 unspecified) postoperative humeral fractures occurred in 4019 primary shoulder arthroplasties (0.9%).5 Chin et al reported on only 1 postoperative fracture in 431 patients (0.2%) with a mean follow-up of 4.2 years, whereas Atoun et al reported four fractures in a series of 31 short-stemmed reverse total shoulder arthroplasty (RTSA) implants (12.9%).8,12 In summary, the postoperative incidence varies between 0.2% and 12.9% (TABLE 40.2).
TABLE 40.1 Summary of Reported Intraoperative Incidences of Periprosthetic Fractures in Both Primary and Revision Shoulder Arthroplasty
to surgeon differences and the rationale of using the superior approach in less-complicated cases than to the approach itself. Higher incidences of intraoperative fractures were also found for RTSA and stemmed HAs compared to those for anatomical and resurfacing arthroplasties. This trend correlated to a relative risk of 1.4 for RTSA and 1.9 for HA compared to TSA in a multivariable analysis adjusting for age, sex, indication for surgery, and American Society of Anesthesiologists grade. Taking into consideration that the former two implant types will more often be utilized in acute or trauma settings and for patients with a larger inherent risk for fractures, it remains difficult to directly attribute the higher risk solely to the implant type when different implants would have been selected based upon the operative indications.3 While revision arthroplasty itself is a significant risk factor for intraoperative periprosthetic humeral fractures, subgroup analysis of revision cases showed that female sex, history of prior instability, and prior HA are also risk factors with an
odds ratio of 2.41 (P = 0.03), 2.65 (P = 0.02), and 2.34 (P = 0.03), respectively.7 Interestingly, a history of a prior cemented primary arthroplasty did not significantly increase the risk of intraoperative fractures in this study.
TABLE 40.2 Summary of Reported Postoperative Incidences of Periprosthetic Fractures in Both Primary and Revision Shoulder Arthroplasty