Paraspinal approach to the far lateral disc herniations: retrospective study on 42 cases.

Forty-two patients underwent surgery for far-lateral disc herniations. Average patient age was 45.1 years, 28 patients were male and 14 female. The level concerned most was L4-5 disc (55%). A paramedian muscle-splitting intertransverse approach is described for this type of disc herniation. This method allows direct visualization of the disc and root involved and does not provide bone resection and important surgical manipulation. Ninety-one percent of the patients reported excellent or good results according to Macnab outcome criteria with an average follow-up of 32.5 months (range 1-5 years). Twelve patients (28.6%) developed postoperative transient radicular pain that disappeared in 15-21 days after analgesic therapy. There were no recurrences or spinal instability. The paramedian muscle-splitting intertransverse approach is a rational technique. Its advantages are that the spine is not opened and spinal stability is maintained. It requires minimal soft-tissue and bone resection and the herniated disc is directly visualized. Moreover, it contains minimal manipulation of the neuro-vascular structures and avoids significant muscle retraction. However, it requires an adequate learning curve and good familiarity with microsurgical techniques.