Fenestrated Pedicle Screws in Spinal Oncology: Technique and Comparative Retrospective Analysis.

Abstract

The use of spinal stabilization with decompression has been shown to improve survival, spinal stability, and ambulatory status in patients with metastatic spinal tumors. However, the poor bone quality typically seen in these patients can prevent adequate stabilization. Fenestrated pedicle screws permit augmented fixation via injection of bone cement into the vertebral body upon screw placement, potentially mitigating the difficulties in achieving adequate stabilization in these patients. To compare surgical outcomes of posterior spinal fusion in patients with cancerous spinal lesions between polymethyl methacrylate cement-augmented fenestrated screws and standard pedicle screws. A total of 19 consecutive patients with cancerous spinal lesions receiving posterior spinal fusion (PSF) with pedicle screws from a single surgeon were retrospectively reviewed for demographic information, comorbidities, surgical parameters, and outcomes. Ten patients underwent PSF with cement augmentation, whereas 9 underwent standard PSF. There was no significant difference in demographics, comorbidities, or surgical characteristics. Operative time was significantly greater in the cement-augmented group (302 ± 100 minutes vs 203 ± 55 minutes; P = .015). There was no significant difference in rates of operation or readmission between the cohorts nor was there any significant difference in discharge disposition. There was 1 case of surgical site infection (in a patient with a fenestrated screw) and no cases of cement extravasation. No instances of mechanical hardware failure were recorded. Fenestrated screws confer similar risk profiles as nonfenestrated screws for posterior spinal fusion in patients with spinal cancer. However, fenestrated screws may affect operative time, radiation exposure, and impose risk of cement extravasation. Cement-augmented fenestrated pedicle screws may be a viable option for patients with poor bone quality associated with metastatic disease without significantly increased rates of surgical complications. 3.