Purpose: The purpose of this study was to assess the efficacy and safety of treating extra-foramen discal herniation via a microsurgical extra-foramen approach.

Material and methods: Fourteen patients underwent this surgical procedure which enables release of the roots outside the foramen while preserving the vertebral isthma. The technique is described in detail together with the postoperative period. All patients were reviewed clinically and radiologically at at least one year. The PROLO score was used to assess results.

Results: Among the 14 operated patients, good or excellent results were obtained in 13, fair results in one. There was no postoperative neurological deficit. The small number of cases in this series did not allow a statistical analysis of this uncommon clinical presentation.

Discussion: The extra-formamen approach is an interesting alternative to isthmic resection requiring fixation for the treatment of disc-root conflicts in the extra-foramen position. With appropriate surgical skill, the technique is safe.