Use of freeze-dried bone allografts in osteoporotic patients undergoing median sternotomy

Osteoporosis is a major risk factor for deep sternal wound infection, which is a rare but serious complication after median sternotomy. We investigated the incidence of deep sternal wound infection and the protective effect of bone allografts in osteoporotic patients after sternal approximation. Data were collected retrospectively from consecutive osteoporotic patients who underwent cardiac surgery via median sternotomy. Sternal approximation in the historical control group was performed with conventional steel wire sutures. Subsequent patients underwent conventional wire suturing plus bone allografting to reinforce the sternum. Perioperative management was standardized between groups. Demographics, risk factors, and postoperative outcomes were analyzed. Between January 2010 and March 2017, 284 patients underwent sternal approximation after sternotomy at our hospital. Sternal closure was completed with conventional wire sutures in the first 148 patients (Group A) and with conventional wire sutures plus bone allografting in the subsequent 136 patients (Group B). Baseline characteristics were comparable, with no significant differences between groups. Bone allografting was associated with less postoperative drainage and shorter duration of chest pain. The incidence of deep sternal wound infection was significantly lower in Group B than Group A (0.7 vs. 4.7%, P = 0.042), as was the incidence of sternal instability (0.7 vs. 7.4%, P = 0.043). Bone allografting was a reliable adjuvant method for sternal closure, associated with reduced risk of deep sternal wound infection among osteoporotic patients. Its benefits should be confirmed in larger studies.