Clinical Effect of Transverse Process Hook with K-Means Clustering-Based Stratification of Computed Tomography Hounsfield Unit at Upper Instrumented Vertebra Level in Adult Spinal Deformity Patients

• Published in: Journal of Korean Neurosurgical Society 2023, Vol.66 (1), p.44-52
• Main Authors: Jongwon, Cho, Seungjun, Ryu, Hyun-Jun, Jang, Jeong-Yoon, Park, Yoon, Ha, Sung-Uk, Kuh, Dong-Kyu, Chin, Keun-Su, Kim, Yong-Eun, Cho, Kyung-Hyun, Kim
• Format: Article
• Language: Korean
• ISSN: 2005-3711; 1598-7876

Objective : This study aimed to investigate the efficacy of transverse process (TP) hook system at the upper instrumented vertebra (UIV) for preventing screw pullout in adult spinal deformity surgery using the pedicle Hounsfield unit (HU) stratification based on K-means clustering. Methods : We retrospectively reviewed 74 patients who underwent deformity correction surgery between 2011 and 2020 and were followed up for >12 months. Pre- and post-operative data were used to determine the incidence of screw pullout, UIV TP hook implementation, vertebral body HU, pedicle HU, and patient outcomes. Data was then statistically analyzed for assessment of efficacy and risk prediction using stratified HU at UIV level alongside the effect of the TP hook system. Results : The screw pullout rate was 36.4% (27/74). Perioperative radiographic parameters were not significantly different between the pullout and non-pullout groups. The vertebral body HU and pedicle HU were significantly lower in the pullout group. K-means clustering stratified the vertebral body HU ≥205.3,