Microsurgical interlaminary vertebro- and kyphoplasty for severe osteoporotic fractures

Object. Percutaneous vertebro- and kyphoplasty have become established methods for the treatment of uncomplicated osteoporotic vertebral fractures. In the setting of severe fractures involving fragmentation of the posterior wall and neural compromise, however, decompressive surgery cannot be performed and epidural cement leakage is poorly controlled. A microsurgical interlaminary approach for venebro- and kyphoplasty was developed to allow spinal decompression and control of the spinal canal during augmentation. Methods. Interlaminary vertebro- or kyphoplasty was performed in 24 patients with osteoporotic fractures involving neural compression or posterior wall fragmentation. After unilateral microsurgical fenestration, decompression of the spine, and gentle mobilization of the thecal sac, vertebro- or kyphoplasty was performed directly through the posterior wall of the fractured vertebral body. Cement was injected under microscopic and fluoroscopic control, with the option of immediate exploration of the exposed spinal canal. Thirty-four levels (T-8 to L-5) were treated. Mean blood loss was less than 100 ml and augmentation added 10 to 40 minutes to the entire procedure. Cement leakage associated with the kyphoplasty procedure was less than that in vertebroplasty. There were no major complications. One patient was lost to follow up. Clinical outcome was good or excellent in 17 of the 23 patients available for follow-up (1 to 31-month) evaluation. Conclusions. The present microsurgical interlaminary approach for vertebro- and kyphoplasty enables treatment of severe osteoporotic fractures involving fragmentation of the posterior wall and neural compromise. Decompressive surgery is possible and the risk of epidural cement leakage is controlled intraoperatively. This technique can be regarded as a procedure on the treatment continuum between percutaneous augmentation and conventional open reconstruction.