Abstract
Introduction: Titanium mesh cages (TMC) for the reconstruction of thoracolumbar vertebral body defects offer an alternative to structural iliac crest autograft or allograft. The stability and safety of these cages has not been addressed.
Aim: To assess the stability and safety of titanium mesh cages in the reconstruction of thoracolumbar vertebral body defects.
Method: Independent radiological review before and after surgery, and at follow-up was performed for 27 patients having implantation of TMCs. Measurements of thoracolumbar kyphosis, cage settling, translational deformities and any evidence of implant failure were recorded.
Results: Indications for reconstruction with TMC included burst fracture (13), post-traumatic kyphosis (8), primary tumour resection (3), debridement of infection (1) and stabilisation of severe kyphotic deformity in achondroplasia with spinal stenosis (2). Kyphoses were corrected by a mean of 12 degrees (61%, range: zero degrees to 38 degrees, 0% to 85%). No cage moved. One patient had a recurrence of the kyphosis of more than five degrees (12 degrees). Five patients demonstrated some settling of the cage within adjacent vertebral bodies (1% to 8%, mean = 3.4% of height loss over length). Translational malposition of three cages occurred. One of these cases demonstrated the maximum settling and another was associated with the only case of instrumentation failure. Spinal canal intrusion did not occur.
Conclusions: We found that the use of TMCs was safe when managing vertebral body reconstruction. Significant kyphosis or translational deformity did not occur, however minor cage settling within adjacent vertebra did. The fusion rate is unknown as the mesh cage obscured graft maturation. Construct failure only occurred after pre-operative translational malalignment could not be corrected. This demanding procedure offers a reconstructive option with superior structural stability and reduced bone grafting morbidity.
The abstracts were prepared by Professor Alan Thurston. Correspondence should be addressed to him at the New Zealand Orthopaedic Association, PO Box 7451, Wellington, New Zealand.