3 The procedure
3.1 The aim of lateral interbody fusion in the lumbar spine is to achieve spinal fusion by a side or lateral approach, to avoid the major muscle groups in the back (posterior approach) or the organs and blood vessels in the abdomen (anterior approach).
3.2 The procedure is done with the patient under general anaesthesia. A probe is inserted laterally through the psoas muscle, under fluoroscopic guidance, to lie alongside the affected disc. A posterior incision is also sometimes made, to allow access for manipulation of the probe. Nerve monitoring is recommended by many specialists. Dilators are inserted around the probe and a retractor is positioned to give the surgeon direct access to the spine. A discectomy is carried out and a cage implant inserted to hold the vertebrae in position. A bone graft (usually from the hip) is inserted between the 2 vertebrae, sometimes with additional support from screws, plates or rods. The procedure may be done at more than 1 level during the same operation. A recent variation of this procedure is oblique lateral interbody fusion, which involves retroperitoneal access anterior to the psoas. It may take a few months before patients are able to return to their normal activities after the procedure.
3.3 There are a number of different devices used for this procedure.