Minimal invasive lumbar spine revision surgery at distance from the dura and postsurgical scar tissue: Extraforaminal Lumbar Interbody Fusion (ELIF).

Lumbar spine revision surgery is considered as challenging and related to longer operation time and complications because of the loss of anatomical landmarks and the formation of postoperative epidural fibrosis. Minimal invasive lumbar spinal surgery techniques have been refined over the last 5 years but the reexposure of the dura, the formation of postsurgical scar tissue and related dural tears remain a source of complications. For lumbar spinal revision surgery we advocate the minimal invasive Extraforaminal Lumbar Interbody Fusion (ELIF) technique. It employs a working corridor of 45° relative to the midline. This angle permits bypassing laterally the dural sac and postoperative epidural fibrosis so that dural tears do not occur. ELIF is performed without an expandable tubular retractor system, it is atraumatic following the natural intermuscular cleavage plane between the multifidus muscle and the longissimus thoracis muscle pars lumborum. Postoperatively the muscles do not show signs atrophy or fatty degeneration. In case of discectomy alone there is no need for the removal of the facets, if intracanalar lesions are targeted the partial removal of the superior facet is sufficient. ELIF represents an alternative to posterior lumbar interbody fusion (PLIF), conventional open transforaminal lumbar interbody fusion (TLIF), and minimal invasive (MIS) TLIF for lumbar spinal revision surgery.

Epidural Fibrosis Seen from a Different Angle: Extraforaminal Lumbar Interbody Fusion.

Background Postoperative epidural fibrosis (PEF) localized around the exposed dura and nerve roots is a known radiologic entity seen after lumbar surgery. Although excessive PEF is associated with residual and new lumbar pain and radiculopathy, its role as the generator of the pain is still discussed. Various materials acting as an adhesion barrier have been tested. There is no undebated class I evidence that any one of them is suitable to reduce or avoid PEF and provide a better clinical outcome. In revision surgery, the dissection of epidural scar tissue is time consuming and related to an elevated risk of dural tear and nerve damage. To avoid the formation of posterior PEF, we propose a surgical approach whose working corridor is situated lateral to the dural sac and the nerve roots: the extraforaminal lumbar interbody fusion (ELIF) technique. Methods Description of ELIF surgical technique. Conclusions The ELIF technique is a muscle-sparing approach to the intervertebral disk space and the spinal canal that avoids the formation of posterior PEF. It represents an option to treat various degenerative lumbar spinal diseases as well as offering another approach for revision surgery in patients who have developed PEF.

Extraforaminal Lumbar Interbody Fusion at the L5-S1 Level: Technical Considerations and Feasibility.

Background Extraforaminal lumbar interbody fusion (ELIF) surgery is a muscle-sparing approach that allows the treatment of various degenerative spinal diseases. It is technical challenging to perform the ELIF approach at the L5-S1 level because the sacral ala obstructs the view of the intervertebral disk space. Methods We reported earlier on the ELIF technique in which the intervertebral disk is targeted at an angle of 45 degrees relative to the midline. In this article we describe the technical process we developed to overcome the anatomic relation between the sacral ala and the intervertebral disk space L5-S1 that hinders the ELIF approach at this level. We then report in a retrospective analysis on the short-term clinical and radiologic outcome of 100 consecutive patients with degenerative L5-S1 pathologies who underwent ELIF surgery. Results The L5-S1 ELIF approach could be realized in all patients. The short-term clinical outcome was evaluated 5 months after surgery: 92% of the patients were satisfied with their postoperative result; 8% had a poor result. Overall, 17% of the patients presented light radicular or low back pain not influencing their daily activity, and 82% of the patients working before surgery returned to work 3 to 7 months after surgery. The radiologic outcome was documented by computed tomography at 5 months after surgery and showed fusion in 99% of the patients. Lumbar magnetic resonance imaging performed in 5 patients at 6 months after surgery revealed the integrity of the paraspinal muscles. Conclusions ELIF surgery at the L5-S1 level is technically feasible for various degenerative spinal diseases. Analysis of the clinical and radiologic data in a consecutive retrospective cohort of patients who underwent this surgical procedure showed a good short-term clinical outcome and fusion rate.

Unilateral Extraforaminal Lumbar Interbody Fusion (ELIF): Surgical Technique and Clinical Outcome in 107 Patients.

STUDY DESIGN: Description of the technique and retrospective study of patients treated with unilateral extraforaminal lumbar interbody fusion (ELIF) for degenerative lumbar spinal disorders. OBJECTIVE: To investigate clinical and radiologic outcome of patients treated with unilateral ELIF. SUMMARY OF BACKGROUND DATA: Lumbar interbody fusion is the classic treatment for higher grades of degenerative disk disease or lumbar segment instability and is performed by posterior (PLIF), posterolateral, or anterior (ALIF) approaches. Those techniques are well established with known limitations and complications. Today, minimally invasive procedures generate more interest especially in terms of muscle damage to achieve better functional outcome. We introduce a unilateral extraforaminal fusion technique which respects neural as well as muscle structures aiming to preserve function. METHODS: Intraoperative and perioperative data, neurological status, Oswestry Disability Index, the Visual Analogue Scale for leg and back pain, and patient satisfaction were investigated preoperatively and at latest follow-up. Fusion status was controlled by x-ray and CT scans at a 6 months' follow-up investigation. RESULTS: A total of 107 patients [female/male: 67/40; average age, 52.8 (± 13.8) y] were included at a maximum of 31(± 9.4) months. Complications occurred in 4% of patients. Transient radicular pain was investigated in 16 patients. The Oswestry Disability Index and the Visual Analogue Scale for back and leg pain improved significantly. Patients showed a short hospital stay and high percentage of return to work ratio (70%). Fusion was achieved in 97% of patients. CONCLUSIONS: The unilateral ELIF fusion technique demonstrates encouraging clinical and radiologic midterm outcome that for some indications is comparable with established fusion techniques.