Purpose of the study: Revision surgery for scoliosis in adults is a technical challenge. Indications include flat back, non-union, and syndromes adjacent to the instrumentation The purpose of this work was to evaluate the pertinence of the transforaminal lumbar interbody fusion (TLIF) method for revision surgery for scoliosis in adults.

Material and methods: In our spinal surgery unit, 23 patients underwent revision surgery for thoracolumbar and lumbar scoliosis. A unique posterior approach was used. The TLIF was performed systematically at the lumbosacral level, at the non-union when it was present, and at the level of the Smith-Petersen osteotomies, as well as the levels above and below a transpedicular osteotomy. Seventeen patients presented flat back, ten non-union, five degenerative disease distal to the instrumentation and one degeneration proximal to the instrumentation. Nine patients had several indications for surgical revision. Five transpedicular osteotomies were performed in five patients.

Results: Mean follow-up was 30 months (range 18–48). On average 2.3 levels (range 1–4) were involved in the TLIF. The fusion was extended to the sacrum in 22 patients. The mean operative time was 5h50m (range 3–8 hours). Mean blood loss was 2100ml (400–4500). Postoperative lumbar lordosis (L1S1) was 53.5°, giving an improvement of 23° copared with the preoperative lordosis. Among the postoperative complications, there was one neurological complications which recovered partially at last follow-up one case of deep infection of the operative site which require partial removal of the implants and one case of recurrent non-union. There was no loss of correction in the frontal or sagittal planes with the exception of one patient who developed an infection. None of the patients in the series required complementary anterior surgery.

Conclusion: For revision surgery of scoliosis in the adult, a circumferential arthrodeis is needed to maintain the fusion. The TLIF method has the advantage of allowing intersomatic fusion via the posterior approach alone without opening the spinal canal. We consider that the TLIF technique is an alternative to two-phase procedures for revision surgery for scoliosis in adults. This method has given a good percentage of fusion in our series with little loss of correction.

Purpose of the study: Multisegmentary pedicle screws are becoming increasingly popular for idiopathic scoliosis in adolescents. For several years correction of the axial deformity has been achieved by vertebral rotation. Use of the EOS radiographic system and the sterEOS software enables a precise calculation of the vertebral rotation in the different plans while exposing the patient to reduced radiation doses. The purpose of this study was to determine the efficacy of the vertebral rotation technique for the correction of axial rotation of the apical vertebra (ARAV).

Material and method: This was a comparative prospective study. Two groups of ten patients underwent surgery for idiopathic scoliosis of the thoracic spine (Lenke 1 and 3). A posterior procedure was performed in all cases to achieve insertion of multiple level pedicle screws. In group 1, the correction was achieved by rotation of the rod and in group 2 by translation and veterbral rotation using the vertebral column manipulation (VCM) technique. Preoperative and 3-month postoperative EOS images were analysed by a radiologist and the spinal surgeon, both blinded to the operative technique. Two radiological parameters were analysed and compared. ARAV was calculated using the pelvic reference; any position error at image acquisition was thus automatically corrected.

Results: Mean age at surgery was 14 years (range 11–19); the two groups were not significantly different for epidemiological parameters, duration of hospital stay, type of curvature, preoperative radiological parameters, axial rotation of the apical vertebra preoperatively, and number of vertebrae instrumented or correction of the curvatures. The postoperative ARAV was significantly greater in group 1 (12.4 vs 4.3, p=0.0005) and the ARAV correction was significantly greater in group 2 (13.7 vs 4.5, p=1.9E-5). There were no early postoperative complications in either group.

Discussion: For posterior surgical correction of thoracic or double major idiopathic scoliosis, the VCM technique allows better correction of the ARAV compared with the rod rotation technique. Use of the EOS and the sterEOS software enabled a better evaluation and comprehension of the 3D correction while exposing the patients to a smaller radiation dose.