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at C2 than is provided by the spinous process at C2, which in many cases may be damaged or not present in the case of Spina Bifida occulta at this level. The posterior arches and the graft may be notched to provide greater stability by preventing slippage of the cables. This method provides much improved rotational stability when compared to the gallie fusion, and the posterior laminar clamps. This technique also simplifies the graft construction when compared to the brooks fusion and also requires ½ the number of sublaminar passes with the cable or wire. The advantage of this technique over the transarticular screws and C1 lateral mass plates is the same as the other laminar techniques, which is to avoid the vascular complications of the lateral mass techniques.
Possible drawbacks to this technique include an increased risk of spinal cord damage by the placement of the sublaminar wires at C2. There also may be increased A-P slippage of C1 on C2 when compared to the gallie and Sonntag techniques due to the lack of the S-shape curve of the cable lying in the sagittal plane at the inferior surface of the graft, however the amount of force required to cause such a slip would be likely to cause damage to any of the constructs described above.
In conclusion, this technique may provide an alternative to the classic methods of posterior fixation of the Atlanto-axial joint. It may prove to be especially useful in the case of damage to the spinous process of C2 or a congenital absence of the C2 spinous process. By placing a notch in the posterior arch of C1 or C2 this technique could also be used in the case of an incomplete arch at C1 or C2. The whole construct can also be enforced with a Hydoxyapetite paste which may also increase the strength and fusion rate of this procedure.
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