Direct Lateral Corpectomy and Reconstruction Using an Expandable Cage Improves Local Kyphosis but Not Global Sagittal Alignment

Recently, an expandable cage equipped with rectangular footplates has been used for anterior vertebral replacement in osteoporotic vertebral fracture (OVF). However, the postoperative changes in global alignment have not been elucidated. The purpose of this study was to evaluate local and global spinal alignment after anterior and posterior spinal fixation (APSF) using an expandable cage in elderly OVF patients. This retrospective multicenter review assessed 54 consecutive patients who underwent APSF for OVF. Clinical outcomes were compared between postoperative sagittal vertical axis (SVA) > 95 mm and ≤95 mm groups to investigate the impact of malalignment. SVA improved by only 18.7 mm (from 111.8 mm to 93.1 mm). VAS score of back pain at final follow-up was significantly higher in patients with SVA > 95 mm than SVA ≤ 95 mm (42.4 vs. 22.6, p = 0.007). Adjacent vertebral fracture after surgery was significantly more frequent in the SVA > 95 mm (37% vs. 11%, p = 0.038). Multiple logistic regression showed significantly increased OR for developing adjacent vertebral fracture (OR = 4.76, 95% CI 1.10–20.58). APSF using the newly developed cage improves local kyphotic angle but not SVA. The main cause for the spinal malalignment after surgery was postoperative development of adjacent vertebral fractures.

Autologous bone graft versus PEKK cage for vertebral replacement after 1- or 2-level anterior median corpectomy

OBJECT Anterior cervical corpectomy with fusion has become the most widely used procedure for the treatment of multilevel cervical stenosis. Although an autologous bone graft is the gold standard for vertebral replacement after corpectomy, industrial implants have become popular because they result in no donor-site morbidity. In this study, the authors compared clinical and radiological results of autologous iliac grafts versus those of bone-filled polyetherketoneketone (PEKK) cage implants. METHODS The clinical and radiological data of 46 patients with degenerative multilevel cervical stenosis and who underwent 1- or 2-level anterior median corpectomy between 2004 and 2012 were analyzed. The patients in Group 1 were treated with vertebral replacement with an autologous iliac graft, and those in Group 2 were treated with a PEKK cage implant. Each patient also underwent osteosynthesis with an anterior plate-screw system. Visual analog scale (VAS) and European Myelopathy Scale scores, loss of height and regional cervical lordosis angle, and complication rates of the 2 groups were compared. RESULTS The mean follow-up time was 20 months. In both groups, the VAS and European Myelopathy Scale scores improved significantly. The loss of height was 3.7% in patients with iliac grafts and 5.3% in patients with PEKK implants. The rates of osseous fusion were similar in Groups 1 and 2 (94.7% and 91.3%, respectively). At the end of the follow-up period, none of the patients complained about donor-site pain. One patient in Group 1 suffered a fracture of the iliac bone that required osteosynthesis. Four patients in Group 2 had to receive revision surgery for cage and/or plate-screw dislocation and new neurological deficit or intractable pain. CONCLUSIONS Preoperative pain and radicularand myelopathic symptoms improve after decompression irrespective of the material used for vertebral replacement. The use of PEKK cages for vertebral replacement seems to result in a higher risk of implant-related complications. A prospective randomized study is necessary to supply evidence for the use of autografts and artificial implants after anterior cervical corpectomy with fusion.

Extracoelomic Mini Approach for Anterior Reconstructive Surgery of the Thoracolumbar Area

OBJECTIVE An extracoelomic mini approach is introduced as a less invasive technique for surgery of the thoracolumbar area performed via the anterior approach. METHODS Twenty-one patients with spinal pathological findings at the thoracolumbar junction were assessed. The reasons for surgery were as follows: burst fracture of the first lumbar vertebra (n = 5), degenerative disc at L1–L2 (n = 4), spondylodiscitis at L1–L2 (n = 8) and at T11–L1 (n = 1), pathological fracture of the first lumbar vertebra (n = 2), and pseudarthrosis at T11–L1 after failed reconstruction (n = 1). The anterior surgical procedure was performed via an extracoelomic mini approach. Intersomatic fusion was performed in 13 patients, corpectomy and bone grafting in 4, corpectomy and vertebral replacement with titanium cage packed with bone cement in 3, and removal of a cage in a failed fusion and bridging the defect with a strut bone graft in 1. Posterior instrumentation of the affected segment was performed in the same sitting. RESULTS The mean ± standard deviation of operative time of the anterior procedure was 101.2 ± 36.5 minutes. The mean blood loss during the anterior procedure was 724 ± 483.5 ml. The procedure was safe. No pseudarthrosis was encountered, and the reconstructed bone was stable in the three patients in whom bone cement was used. CONCLUSION The extracoelomic mini approach is less invasive; it results in less incisional morbidity, and it avoids opening the pleural and peritoneal cavities.