Which is Better-Autograft or Allograft?

Bone grafting is one of the surgical considerations that the surgeon and patient need to consider pre-operatively.  Bone grafting is used to prevent deformity and hasten recovery/stabilization at the surgical site.  The bone grafts help preserve disc height during the healing process. 

The two options to consider are allograft and autografts.  Autografts, harvesting tricortical piece of bone from the patient's own iliac crest bone requires a second incision over the anterior superior iliac crest.

An alternate site for harvesting bone is the patient's fibula.  The advantages to using autografts include biocompatibility.  The endogenous bone morphogenic proteins (BMPs), help recruit osteoprogenitor cells to differentiate into osteoblasts.  There is an average of 20% loss in height at each interspace level with autograft fusions.  Research has demonstrated that the autograft is superior in maintaining disk height and graft incorporation.

Allografts are used more frequently today and research has demonstrated that the arthrodesis rates are excellent with ventral cervical procedures.  The reason for the shift includes:  cost/availability, graft harvest morbidity and clinical efficacy.  While the host immune system sometimes adversely affects allograft use when fresh-frozen allografts are used, most surgeons have moved away from fresh-frozen grafts because alternative bone treament methods have resulted in products that don't require refrigeration and are essentially inert from an immunity point of view.

Clinical studies have shown that the autograft is superior to the allograft in both grant incorporation and maintenance of disk height.
However, since surgeons have begun using ventral cervical plating, in combination with allografts, the results surpass the autograft procedures.  Smoking adversely affects the allografts more so than an autograft.  Patients are more likely to prefer the allograft to avoid graft morbidity associated with graft harvesting, such as pain at the harvest site, infection, hematomas, or nerve injury.

Cost comparisons have demonstrated that the processing costs for allografts may be higher but the operation room time for harvesting autografts, as well as treating morbidity associated with autografts also increases the cost of the surgery.  Allograft use in two or more level surgeries needs to be supplemented with ventral instrumentation.

High-risk patients, such as smokers, end-stage renal disease and undergoing three or more levels of arthrodesis are candidates for autografts.  Autografts are more likely to be used in posterior surgical approaches.  The choice between autograft and allograft is just one of the many decisions that impact on the success of cervical fusion surgeries.

If you have any questions regarding the use of grafts during surgical spine or neck procedures, please contact one of the neurosurgeons listed below.

summon.bhattacharjee@neurosciencegroup.com
randall.johnson@neurosciencegroup.com
philip.yazbak@neurosciencegroup.com