Sternal cancellous bone graft harvest for anterior cervical discectomy and fusion with interbody cage devices

Abstract 

Study design

Retrospective chart review, technical note, cohort study.

Objective

To describe the clinical outcome of a modified method of obtaining cancellous autograft from the manubrium of the sternum for use in interbody cages during anterior cervical fusions.

Summary of background data

Harvest of structural grafts from the anterior iliac crest (AIC) for anterior cervical fusion has well-established morbidities. In an effort to minimize morbidity and maximize fusion, we utilized interbody cages filled with autologous cancellous bone. In cases needing corpectomy, local bone graft from the corpectomy is used to fill the cage. In cases needing discectomy alone, no local bone is resected and therefore alternative donor sources must be used if autograft is to be used and the complications of AIC harvest are to be avoided. This technique is especially useful in countries where allograft is either not available or available in limited quantity.

Methods

We have developed a modified technique for the harvest of autologous cancellous graft from the sternum which can be used as a fusion substrate with cervical interbody cages. This technique incorporates either a small incision just above the sternal notch or subcutaneous tunneling from the discectomy incision and use of a bone graft harvester. We retrospectively analyze the clinical outcome and fusion rates.

Results

Using the described technique, one-hundred sternal graft harvests (n=100) have resulted in three minor complications: one wound hematoma which resolved with observation, and two superficial wound infections which required treatment with oral antibiotics. All the patients were satisfied by the cosmetic appearance of the incision. Spinal fusion was achieved in all patients at the end of 12 months.

Conclusions

We describe a modified technique of harvesting the sternal graft and also for the first time describe the long-term clinical outcome of using sternal autograft for ACDF. The sternal manubrium provides a viable alternative to AIC grafting. It confers the advantages of autograft fusion without the complications associated with AIC graft harvesting.

Keywords: Sternal graft, Autograft, Iliac crest graft, Spinal fusion, Cervical fusion