An extreme lateral access for the surgery of lumbar disc herniations inside the spinal canal using the full-endoscopic uniportal transforaminal approach-technique and prospective results of 463 patients

Study Design. Prospective study of patients with lumbar disc herniations who were operated on with a full-endoscopic uniportal transforaminal approach using an extreme lateral access. Objectives. To examine the technical possibilities of an extreme lateral access for full-endoscopic uniportal transforaminal surgery of lumbar disc herniations within the spinal canal. Also, to assess sufficient decompression, and the advantages and disadvantages of the minimally invasive procedure. Summary of Background Data. Conventional prolapsed disc operations can result in consecutive damage as a result of traumatization. The usual transforaminal access is posterolateral, and is associated with problems in reaching the epidural space directly with unhindered vision and, thus, with problems of sufficient decompression in lumbar disc herniations within the spinal canal. Methods. A total of 463 patients were observed for 1 year. In addition to general and specific parameters, the following measuring instruments were used: visual analog scale, German version North American Spine Society Instrumentarium, Oswestry low back pain disability questionnaire. Results. There were no complications. Of the patients, 81% reported no longer having leg pain, and 14% had occasional pain. There was no worsening. The results were constant and are equal to those of conventional procedures. No patients presented with neural scarring; 7% had recurrence of the prolapse. The extreme lateral access was necessary to reach the sequestered material. Conclusions. The technique presented is an adequate and safe alternative to conventional procedures, and has the advantages of a truly minimally invasive procedure. The extreme lateral access is required for the indications described. There are clear limitations outside these indications. The possibility of selecting an access from posterolateral to extreme lateral now enables surgery of lumbar disc herniations inside and outside the spinal canal.