Intraoperative Radiation Exposure in Adolescent Idiopathic and Neuromuscular Scoliosis.

BACKGROUND: Intraoperative imaging is often used to aid pedicle screw placement during scoliosis operations. Higher rates of cancer and death have been observed in orthopaedic surgeons and radiation technologists, including a fourfold higher rate of breast cancer in female orthopaedic surgeons. The purpose of this study was to evaluate variability in intraoperative radiation during spinal fusions for both adolescent idiopathic scoliosis (AIS) and neuromuscular scoliosis (NMS). METHODS: A retrospective review of posterior spinal fusion and segmental spinal instrumentation for scoliosis performed by pediatric orthopaedic surgeons from 2017 to 2019 at a single institution was performed. Inclusion criteria included: a diagnosis of AIS or NMS and patients between 8 and 18 years of age. Exclusion criteria included: revision surgery, use of intraoperative navigation, and patients younger than 10 at the time of scoliosis onset within the AIS cohort. Data collected included: preoperative curve, body mass index (BMI), number of levels fused, number of Ponte osteotomies, and fluoroscopy time. One-way analysis of variance tests, Bonferroni post hoc tests, independent t tests, and Pearson correlations were utilized with significance determined at the 95% confidence level ( a = 0.05). RESULTS: A total of 148 patients were included in the study. The average fluoroscopy time was 143 ± 67 seconds. Patients with NMS had higher average fluoroscopy times (193 ± 75 s) compared with patients with AIS (129 ± 58 s, P < 0.001). In patients with AIS, fluoroscopy time correlated to the patient's preoperative curve ( r = 0.182, P = 0.050). Patients with AIS with fewer than 12 levels fused had significantly less radiation exposure than those with 12 or more levels fused ( P = 0.01). When controlling for the number of levels fused, patients with AIS with higher BMIs had significantly greater fluoroscopy times ( P = 0.001). In patients with NMS, fluoroscopy time negatively correlated with BMI ( r = -0.459, P = 0.009) and positively correlated with a preoperative curve ( r = 0.475, P = 0.007). CONCLUSION: Fluoroscopy times vary greatly during adolescent spinal fusions for scoliosis. Longer fluoroscopy times are correlated with: NMS diagnosis, larger preoperative curve, BMI, and number of levels fused. Surgeons' knowledge of factors affecting fluoroscopy time will increase awareness and may be the first step in decreasing intraoperative radiation risks. LEVEL OF EVIDENCE: Level III; Therapeutic-a retrospective study.

Mechanical Failure of 2 Cannulated Screw Fixation for Unstable SCFE: A Case Report.

CASE: A 13-year-old obese boy presented with an acute-on-chronic unstable left slipped capital femoral epiphysis (SCFE). He underwent in situ surgical fixation with two 6.5-mm fully threaded cannulated screws. At 6 months, he presented with mechanical failure of both screws. He underwent screw removal, revision in situ fixation, a peritrochanteric flexion and internal rotational osteotomy, and an open femoroplasty. The osteotomy healed at 6 weeks. The femoral physis took an additional year to close. CONCLUSION: This case highlights an uncommon complication of in situ pinning of SCFE, discusses revision fixation options, and suggests possible prolonged physeal closure in severe slips.