Calcium sulfate paste graft with locking plate for proximal humeral fractures: no functional benefit

BACKGROUND: Osteosynthesis of proximal humeral fractures (PHFs) using locking plates (LPs) is associated with a high complication rate, and graft augmentation aims to reduce it. Our study compared clinical and radiographic outcomes as well as complications in older patients with 3- or 4-part PHFs operated with an LP with or without synthetic bone graft. METHODS: A prospective, randomized controlled trial included 70 patients with 3- or 4-part PHFs that were randomly assigned to osteosynthesis using an LP with calcium sulfate paste bone graft (Graft Group) or without graft (Control Group). The primary outcome was the 12-month Constant-Murley score. The secondary outcomes included the 3- and 6-month Constant-Murley score; the 3-, 6-, and 12-month University of California at Los Angeles score; American Shoulder and Elbow Surgeons score; visual analog scale for pain; Disabilities of the Arm, Shoulder, and Hand score; active range of motion; the 12-month Individual Relative Constant, patient satisfaction; abduction strength, head-shaft angle, and humeral height; and consolidation and complications on the first postoperative day and at 6 weeks, 3 months, 6 months, and 12 months. RESULTS: No differences were evidenced at 12 months between the Graft Group and Control Group, respectively, on the Constant-Murley score (67.7 ± 13.0 vs. 70.3 ± 9.4 points, P = .328), Individual Relative Constant (79.3 ± 9.7% and 81.6 ± 6.3%, P = .227), University of California at Los Angeles, American Shoulder and Elbow Surgeons, visual analog scale, Disabilities of the Arm, Shoulder, and Hand scores, active range of motion, and satisfaction rate (97.2% and 100%, P = .328). The abduction strength was significantly higher in the Graft Group (5.5 ± 1.8 vs. 3.7 ± 0.9 N, P < .001). No differences were shown between the mean head-shaft angle of healthy and operated shoulders in the groups on the first day (P = .455) and at 12 months (P = .671), likewise between the groups' mean humeral height on the first day (P = .298) and at 12 months (P = .354). There was a 100% consolidation with a mean of 7.7 and 8.3 weeks, respectively (P = .347) without any osteonecrosis in the Graft Group. There were no differences in patients with complications (13.9% vs. 29.4%, P = .111) or those who underwent reoperations (5.5% vs. 11.8%, P = .325). However, the total number of complications was significantly lower in the Graft Group (50.0% vs. 16.7%, P = .007). CONCLUSION: Our study confirms that calcium sulfate synthetic bone substitute augmentation did not alter the Constant-Murley score or most secondary clinical and radiographic outcomes in older patients with 3- or 4-part PHFs. However, overall complications were reduced, and the abduction strength was higher in the Graft Group.