Bone Graft Choices for Cervical Spine Fusion
Using Autograft v. Allograft for Fusion
There are different risks and advantages for using either your own bone (autograft) or cadaver bone (allograft). The things to consider are fusion rate and healing time, graft collapse, infection and donor site issues.
Fusion rate is the percentage of full incorporation of the graft bone into your native vertebra. With autograft (your own bone) for a single level, the rate is 95-98% With allograft (cadaver bone), it is 92-95%.
Healing time is how long it takes for the bone to become fully incorporated. With autograft, it takes about 6 weeks. With allograft, it takes 3-4 months.
Graft collapse is the narrowing of the graft placed in between the vertebra because of collapse of the internal architecture of the graft. The graft still will go on to fusion most of the time but with a loss of the original intended positioning. It is rare with autograft but with allograft, it can occur in the 5-10% range. This may be insignificant or lead to a failure of fusion.
Infection is rare in neck surgery but can occur. There are extremely rare cases of infection being transmitted by an allograft (cadaver bone). There are also two separate incisions with autograft usage which theoretically can increase the risk of infection but this is also rare.
With allograft, there is no donor site obviously as the graft comes from a cadaver. With autograft, the graft comes from a small one inch incision made over the pelvis at approximately the belt level. There can be some residual discomfort from this incision.
Using Instumentation in the Neck (Cervical Plate)
Using a plate during surgery helps to stabilize the placement of the graft and make it heal faster. It also eliminates the need for a neck collar after the initial seven days post-op.
If a plate is used to stabilize the graft, the neck collar can normally be taken off in one week. Exercises should be done after one week post op to keep the neck muscles from becoming deconditioned. These are “around the worlds” and “yes- nos”.