Comparative analysis of clinical factors associated with pedicle screw pull-out during or immediately after surgery between intraoperative cone-beam computed tomography and postoperative computed tomography

• Published in: BMC musculoskeletal disorders 2021-01, Vol.22 (1), p.55-55, Article 55
• Main Authors: Sumiya, Satoshi, Fukushima, Kazuyuki, Kurosa, Yoshiro, Hirai, Takashi, Inose, Hiroyuki, Yoshii, Toshitaka, Okawa, Atsushi
• Format: Article
• Language: English
• Subjects: Aged; Back surgery; Comparative analysis; Computed tomography; Cone-Beam Computed Tomography; Cone‐beam computed tomography (CBCT); Connecting rod; CT imaging; Diffuse idiopathic skeletal hyperostosis (DISH); Humans; Lumbar Vertebrae - diagnostic imaging; Lumbar Vertebrae - surgery; Medical imaging; Metastases; Metastasis; Methods; Musculoskeletal diseases; Orthopedic implants; Osteoporosis; Patient monitoring; Patients; Pedicle screw pull‐out; Pedicle Screws - adverse effects; Retrospective Studies; Risk factors; Sensors; Spinal cord injuries; Spinal Fusion - adverse effects; Spondylitis; Statistical analysis; Surgery; Thorax; Tomography, X-Ray Computed; Vertebrae
• ISSN: 1471-2474; 1471-2474
• DOI: 10.1186/s12891-020-03916-9

No studies to date have elucidated the clinical factors associated with pedicle screw pull-out during or immediately after surgery. The aim of this study was to assess the frequency of pedicle screw pull-out by comparing intraoperative scans obtained using cone-beam computed tomography (CBCT) with postoperative scans obtained using computed tomography (CT). We also sought to determine the incidence of pedicle screw pull-out and identify relevant risk factors. This was a retrospective analysis of prospectively collected data for 742 pedicle screws placed in 76 consecutive patients who underwent at least triple-level posterior fixation for thoracic or lumbar spinal injury, spinal metastasis, or pyogenic spondylitis between April 2014 and July 2020. Pedicle screw pull-out distance in the axial and sagittal planes was compared between CT scans obtained 2 days postoperatively and CBCT images acquired intraoperatively. Risk factors associated with pedicle screw pull-out were investigated by multivariate logistic regression analysis. Pedicle screw pull-out was seen with 58 pedicle screws (7.8%) in 26 patients (34.2%). There were significant differences in age, number of fused segments, frequency of diffuse idiopathic skeletal hyperostosis (DISH), and medical history of osteoporosis for pedicle screw pull-out. Risk factors for pedicle screw pull-out were older age (odds ratio 1.07, 95% confidence interval 1.02-1.130) and a diagnosis of DISH (odds ratio 3.35, 95% confidence interval 1.12-10.00). Several cases suggest that use of connecting rods was an important factor in intraoperative pedicle screw pull-out. Our findings suggest that age, number of fused segments, presence of DISH, and medical history of osteoporosis are risk factors for pedicle screw pull-out, with the greatest being older age and DISH.