Paraspinal-approach transforaminal lumbar interbody fusion for the treatment of lumbar foraminal stenosis

Object. Foraminal stenosis is a common cause of lumbar radicular symptoms. Recognition of the dynamic pathology, as well as the static anatomical changes, is important to achieving successful surgical outcomes. Excessive facet and anulus removal leads to subsequent disc space narrowing and/or segmental instability, which can cause poor results after decompressive surgery. The objective of this study was to evaluate the efficacy of the paraspinal-approach transforaminal lumbar interbody fusion (TLIF) in the treatment of lumbar foraminal stenosis. Methods. Twenty levels of lumbar foraminal stenosis in 16 patients were treated using an instrumented paraspinal-approach TLIF. There were 12 single-level and 4 two-level cases. Pathologies included foraminal stenosis at 13 levels and lateral disc herniation with disc space narrowing at 7. Results. In all patients, preoperative radicular symptoms and mechanical low-back pain were resolved immediately after the operation and leg weakness improved gradually. The recovery rate using the Japanese Orthopaedic Association score was 89.1%. Bony union was achieved within 6 months after the operation in all cases. Postoperative MR imaging showed minimal changes in the paraspinal muscles in the single-level cases. Conclusions. The paraspinal-approach TLIF is a minimally invasive, safe, and secure procedure for treating lumbar foraminal lesions. Direct visualization and decompression for the foraminal lesion, distraction of the collapsed disc space, and stabilization of the unstable segments can be achieved simultaneously through the paraspinal approach, which produces successful clinical and radiological results. (DOI: 10.3171/2010.4.SPINE09691)