Sternal fixation and autologous bone grafting for post sternotomy non-union: a case series

Sternal non-union is a rare but serious complication post cardiac surgery. It is defined as sternal pain with clicking, instability or both, lasting for more than 6 months in the absence of infection. It usually presents in an outpatient setting and is confirmed on computed tomography (CT) scanning. Despite many corrective methods described in the literature, there is a lack of consensus amongst cardiac surgeons as to the ideal surgical management of sternal non-union post cardiac surgery. We describe our experience of sternal plating combined with autologous iliac crest bone grafting (AICBG) for sternal fixation and explore its safety and feasibility in patients with non-union post cardiac surgery.

Patients who underwent sternal non-union surgery between 2015 and 2020 were included. Their primary cardiac surgical interventions occurred between 2011-2018. Demographic, clinical and outcome data obtained from a local database was analyzed retrospectively. Surgical procedure: sternal edge debridement, plate fixation with screws, filling with AICBG. Due to variable pathoanatomy of non-union, residual wires and multiple fragments of poor bone quality were cut and the sternal halves were stabilised by titanium plates and screws. These were reinforced with AICBG applied in the residual sternal gap created after debridement. Seven patients were included in the study. Median age was 65 years (54-75 years). Four patients (57.1%) were male. Demographic risk factors for sternal non-union prior to their initial cardiac surgery included diabetes (N=6), smoking history (N=3), and a median body mass index (BMI) of 31.2 kg/m². The median interval between primary surgery and sternal fixation was 2.2 years. There were no perioperative deaths. Complications post sternal plating such as iliac crest pain (n=3) and acute tubular necrosis (n=1) were managed conservatively with long-term resolution. None of the patients required further intervention post sternal fixation after a mean follow-up of 18.0 months.

The use of AICBG in addition to sternal plating is a viable and innovative method of treating sternal non-union post-cardiac surgery with lasting effects and without any serious long-term complications. However, further larger studies are required to validate our results.