Frequency and specific surgical management of far lateral lumbar disc herniations

Abstract

The analysis of pre-operative computer-assisted tomograms and myelograms in a series of 694 operated lumbar disc herniations showed that a far lateral disc prolapse occured in 7% of the cases. Within the group of those far laterally herniated discs 3% of the herniations were predominantly located in the intervertebral foramen, whereas 4% of the protruded discs were mainly situated extraforaminally compressing the spinal nerve in its paravertebral course. By March 1988 40 patients had been operated on for an extraforaminal disc protrusion making use of an external microsurgical exposure (in two cases by a transmuscular approach and in 38 cases via an enlarged midline approach). A medium-term follow-up of these 40 patients revealed a substantial clinical relief of pain in 34 cases (85%). Based on these gratifying results we regard the external exposure of the extraforaminally protruded disc as the treatment of choice.