GRAFT PLACEMENT
A 38-year-old male was prepped and anesthetized for an anterior cervical discectomy, fusion and plating at C5-6. The neurotechnologist used somatosensory evoked potentials of the tibial and ulnar nerves and C5 and C6 dermatome evoked potentials. Spontaneous EMG activity was monitored from the biceps brachii and the deltoid muscle groups.

All studies were stable throughout discectomy. Upon graft placement at C5-6 recordings from the left ulnar showed an increase of cortical latency by greater than 10 percent and reduction of amplitude by more than 50 percent. The left C6 dermatome was not obtainable.

These findings were discussed with the surgeon, who promptly removed the bone graft. Subsequent cortical latencies with ulnar nerve stimulation approximated baseline findings. The left C6 dermatome remained unobtainable. Further decompression was performed at the left C5-6 disc space. Subsequent stimulation of the left C6 dermatome identified readable, repeatable cortical wave morphologies. The graft was replaced without further sequel.