Percutaneous transforaminal lumbar interbody fusion for the treatment of degenerative lumbar instability

OBJECTIVE: Percutaneous spinal instrumentation techniques may be helpful to reduce approach-related morbidity inherent to conventional open surgery. This article reports technique, clinical outcomes, and fusion rates of percutaneous transforaminal lumbar interbody fixation (pTLIF). Results are compared with those of mini-open transforaminal lumbar interbody fixation (oTLIF) using a muscle splitting (Wiltse) approach. METHODS: pTLIF was performed in 43 patients with single-level and 10 patients with bi- or multilevel lumbar discopathy or degenerative pseudolisthesis resulting in axial back pain and claudication, pseudoradicular, or radicular symptoms. Decompression, discectomy, and interbody cage insertion were performed through 18-mm tubular retractors followed by percutaneous pedicle screw-rod fixation. Clinical outcome was assessed by early postoperative pain scores (visual analog,score) and standardized functional outcome questionnaires (American Academy of Orthopedic Surgeons lumbar spine and Roland-Morris low back pain score). Fusion rates were assessed by thin-slice computed tomographic scan at 16 months. Clinical outcome, time in the operating room, intraoperative blood loss, and postoperative access-site pain were compared with an institutional reference series of 67 oTLIF procedures. RESULTS: Excellent and good clinical results were obtained in 46 (87%) out of 53 patients at 16 months. The time spent in the operating room was equivalent and the blood loss reduced compared with oTLIF (P < 0.01). There was no morbidity related to instrumentation. Postoperative pain was significantly lower after pTLIF after the second postoperative day (P < 0.01). The overall clinical outcome was not different from oTLIF at 8 and 16 months. CONCLUSION: pTLIF allows for safe and efficient minimally invasive treatment of single and multilevel degenerative lumbar instability with good clinical results. Further prospective studies investigating long-term functional results are required to assess the definitive merits of percutaneous instrumentation of the lumbar spine.