Changes in the cervical foraminal area after anterior discectomy with and without a graft

A controversial point in the management of patients undergoing anterior cervical discectomy is whether an interbody bone graft should be used. Proponents of interbody grafting claim that without a graft, the disc height and the area of the foramina at that level will decrease postoperatively with the potential for persistent symptoms and/or the development of a radiculopathy. Using a two-dimensional digital planimeter, we measured the cross-sectional area (cm2) of cervical foramina on preoperative and postoperative oblique films in patients undergoing anterior cervical discectomy. Group A patients underwent the insertion of an interbody graft after the discectomy; Group B patients did not. Our results indicate that in all the patients in Group A, there was a statistically significant increase in the area of the foramina (P < 0.001) and in Group B, a statistically significant decrease (P = 0.0005). However, when the absolute change in magnitude of the foramina was measured, without respect to an increase or decrease, there was no statistically significant difference (P > 0.8). There was no statistically significant difference (P = 1.000) in the outcome between the two groups. From an anatomical standpoint, our data support the insertion of an interbody graft if the surgeon wishes to increase the area of the foramen. However, the overall magnitude of change is not significant, which may be a factor in why the clinical outcome is similar in both groups.