Intervertebral disc herniation lateral to the intervertebral foramen (far lateral disc herniation, FLH) usually causes compression of the neural root superior to the respective intervertebral space. Insufficient diagnosis and localization of this specific type of herniation may lead to inadequate surgical treatment. If FLH is found to be the cause of neural compression, it seems obvious that it cannot be reached from an interlaminar approach. Facetectomy is occasionaly used in surgical treatment of FLH by many surgeons, often resulting in segmental instability. Thirty patients with FLH were operated by the authors in two neurosurgical institutions during a two and half-year period (1/98-6/00). Microsur- gical, either paramedian intermuscular or paramuscular approaches were used, thus avoiding the need for a significant interference with articular connections and stability. Very good results were achived in twenty-four patients with a follow-up period longer than six months. Two patients were reoperated for reasons not directly related to the previous procedure. Careful evaluation of clinical signs as well as CT or MRI findings are crucial for disclosing the diagnosis of FLH. The success of a microsurgical paramedian approach is conditioned by perfect anatomical knowledge of the extarforaminal region.

        Key words: far-lateral disc herniation, paramedian approach, disc herniation