To graft or not to graft: rationalizing choice in anterior cervical discectomy

Anterior cervical discectomy has been performed for almost 50 years. Initially, bone grafts were used routinely, but soon their necessity was questioned. It remains disputed to this day. The aim was to establish whether there are grounds for basing choice of technique on individual patient data. The cervical spine radiographs of 148 patients who had undergone grafted or ungrafted anterior cervical discectomy were reviewed and changes in geometry at the operated level were measured. These data were then examined for any correlation between preoperative geometry, choice of operative technique and adverse clinical outcome. Disturbances to spinal geometry after ungrafted discectomy are minimal at disc heights below 4 mm. At and above 4 mm significant settlement and angulation occur. Complications in our series were fewer where small disc spaces were left ungrafted and larger ones grafted. Disc spaces below 4 mm should not be grafted, but spaces of 4 mm or more should.