[Transplantation of allogeneic bone graft in the therapy of massive post-sternotomy defects - 6 years of experience with the method]

Early complications due to deep sternal wound infection pose a serious problem in cardiac surgery, with an up to 40% risk of mortality. Massive loss of sternum bone tissue and adjacent ribs results in major chest wall instability difficult to resolve using classical AO osteosynthesis procedures, causing respiratory insufficiency making the disconnection from artificial pulmonary ventilation difficult, and additional defects of soft tissue healing. Based on orthopaedic experience with bone defect replacement, we used the allogeneic bone graft method to reconstruct the chest wall.

In the period of 20112015 we performed the transplantation of an allogeneic bone graft in 13 patients. In 10 cases, an allograft of the sternum was used, in one case an allograft of the calva bone and in two cases the crushed spongy bone was used. After primary cardiac surgery, a massive post-sternotomy defect of the chest wall developed in all the 13 patients due to deep sternal infection and osteomyelitis of the sternum and adjacent ribs. Vacuum wound drainage was applied in the treatment of all the patients. To stabilize the chest and the graft, transverse titanium plates were used, fixed using bicortical screws. The bone allograft was prepared by the official Tissue Centre. Crushed allogeneic spongy bone was applied to reinforce the line of contact of the graft and the edges of the residual skeleton. In 12 cases, the soft tissue was closed by direct suture of mobilized pectoral flaps. In one case, V-Y transposition of the pectoral flap was performed.

In 8 cases, healing of the reconstructed chest wall occurred without further complications. In 4 cases, additional re-suture of soft tissues and skin in the lower pole of the wound was needed while the patients were still in the hospital. However, excellent chest wall stability along with adjustment of respiratory insufficiency and a very good cosmetic effect in the wound were achieved in all the 12 cases. In two cases, explantation of the plates was required. In one case, severe concomitant complications and no healing of the wound resulted in death within half a year after the reconstruction. The median follow-up period of all patients in the series was 21 months (136). In 5 cooperating patients, scintigraphy of the chest wall was performed repeatedly during the follow-up period showing a high healing activity of the graft and particularly of the crushed spongy bone.

Our existing results show that allogeneic bone graft transplantation is a promising and easily applied method in the management of serious tissue loss in sternal dehiscence with favourable functional and cosmetic effects.Key words: sternotomy deep sternal wound infection massive post-sternotomy defect allogeneic bone graft.