Glenoid cementing may generate sufficient heat to endanger the surrounding bone

Glenoid loosening is a common complication of shoulder arthroplasty. One possible cause is bone necrosis from the exothermic reaction of polymethylmethacrylate. The relationship between the amount of cement used in glenoid fixation and the risk of thermal injury to bone was examined. Glenoid arthroplasty was done on 17 fresh cadaver scapulas, recording the amount of cement used. The bone surface temperature during cement curing was measured using infrared thermography. Using these data and published thresholds for thermal necrosis, the frontal plane area of bone that would be at risk for necrosis in vivo was estimated. The average weight of cement implanted was 5.35 g (2.65-8.08 g). The maximum temperature recorded averaged 64.7 degree C (48.2 degree-76.8 degree C). The area of bone at risk correlated with the amount of cement used. This study indicates that potentially dangerous amounts of heat may be generated during cementing of glenoid components.