Risk Factor Analysis of Bone Cement Leakage for Polymethylmethacrylate-Augmented Cannulated Pedicle Screw Fixation in Spinal Degenerative Diseases

Background We investigated the risk factors of cement leakage (CL) for polymethylmethacrylate-augmented cannulated pedicle screw (CPS) in spinal degenerative diseases and provided technical guidance for clinical surgery. Methods This study enrolled 276 patients with spinal degenerative disease and osteoporosis who were augmented using CPSs (835 screws in total) from May 2011 to June 2018 in our hospital. The patients' age, sex, bone mineral density (BMD), diagnosis, augmented positions, number of CPS implanted, and CL during surgery were recorded. CL was observed by postoperative computed tomography (CT) and was classified by Yeom typing. Results A total of 74 (8.9%) CPSs in 64 patients leaked (23.2%), with 65 (87.83%), 3 (4.05%), and 6 (8.11%) screws showing Types S, B, and C leakage, respectively. CL was significantly correlated with the number and position of screws (P < 0.05), but not with sex, age, and BMD (P > 0.05). The position, number of CPSs, fracture, degenerative scoliosis, ankylosing spondylitis, and revision surgery were risk factors for CL (P < 0.05). Augmentation of the thoracic vertebral body, fracture, and ankylosing spondylitis were independent risk factors for Type S. Augmentation of the lumbar vertebral body, lumbar disc herniation, and lumbar spondylolisthesis were independent risk factors for Type B (P < 0.05). Conclusions CL has a high incidence in clinical practice. To avoid serious complications, high-risk factors for leakage should be addressed. Particularly, it is necessary to develop alternative solutions for the lack of holding force of internal fixation caused by CL during surgery.