Purpose: Circumferential arthrodesis of the lumbar spine is necessary in certain selected situations (lumbar stenosis with instability and preserved disc height or spondylolisthesis). Posterior lumbar interbody fusion (PLIF) raises the risk of significant bleeding and fibrosis around the roots as well as neurological complications. Transforaminal lumbar interbody fusion (TLIF) can avoid excessive bleeding and root displacement. The cages are inserted via a unilateral approach.

Material and methods: This prospective single-centre study included twenty patients (nine men and eleven women), mean age 49 years. Indications for lumbar surgery were degenerative spondylolisthesis in nine patients and discal lumbar pain with foraminal stenosis in five. The clinical status was assessed with the Oswestry score, SF-36 and a visual analogue scale (VAS). Radiological assessment was based on inter-body fusion, segmentary lordosis, and lumbopelvic parameters. TLIF was associated with a posterior approach for insertion of titanium pedicular screws (CDH, Medtronic Sofamor Danek). Temporary unilateral distraction opened the foramen. Unilateral arthrectomy enabled a lateral approach to the disc without involving the roots and avoiding any movement of the dural sac. The disc was resected and the body endplates were prepared before introducing two cages (pyramesh) filled with macroporous ceramic granules (BCP) mixed with autologous bone marrow. Installation to two contourned rods enabled segmentary compression to stabilise the cages in association with posterolateral fusion.

Results: Mean operative time was three hours. Mean blood loss was 400 ml. The patients were verticalised on day three without a corset. Mean follow-up was six months with retrospective evaluation of the Oswestry score, SF-36, and VAS. Postoperative pain resolved rapidly. Two patients developed transient incomplete L5 deficit. Bony bridges around the cases and posterolaterally were identified on the six-month x-rays. Spine view confirmed the quality of the fusion and lumbopelvic parameters revealed restoration of segmentary lordosis.

Conclusion: The unilateral approach for TLIF is a reliable technique which does not compromise the roots. It enables very reliable primary stability and recovery of local segmentary lordosis. We are developing a minimally invasive percutaneous technique for this procedure.

Purpose: Indications for anterior release associated with posterior release for stiff idiopathic scoliosis in adults has varied from institution to institution. The traction view is taken as a useful tool to determine whether anterior release is necessary. The purpose of this study was to validate this hypothesis in a homogeneous group of patients with specifically defined idiopathic scoliosis and to determine predictive value of the traction view. Based on this prediction, we then compared postoperative frontal correction in patients with and without anterior release, performed thoracoscopically.

Material and methods: All patients had idiopathic thoracic scoliosis with a Cobb angle greater than 60° and less than 35% reduction on the standard traction view. Cotrel-Dubousset instrumentation was used for release/posterior fusion procedures. A posterior approach was used alone in group 1 patients (n = 46). Group 2 patients (n = 10) underwent thoracoscopic first intention anterior release/fusion.

Results: The postoperative Cobb angle was strongly correlated with the preoperative angle on the traction view (r = 0.86, p < 0.001). The traction view predicted the postoperative Cobb angle actually achieved rather than the degree of correction of the Cobb angle. The severity of the curvature, 81.5° and 83.3° in groups 1 and 2 respectively, and reducibility on the traction view, 61.6° and 62.1° in groups 1 and 2 respectively, were not different. Likewise the postoperative angles were not significantly different between the two groups (47.4° and 45.4° respectively).

Discussion: The traction views were found to predict reduction of the thoracic curvature even for stiff scoliosis but with a wide error. The two groups were comparable since there was no difference in the mean degree of reducibility under traction. Consequently, anterior release did not appear to improve the postoperative correction in the frontal plane.

Conclusion: The traction view does not appear to be sufficiently discriminating to determine the usefulness of anterior release associated with posterior release for the treatment of stiff idiopathic thoracic scoliosis.