Purpose or Case Report: To evaluate inter observer and intra observer variations for vertebral pedicle morphometeric measurements in pediatric scoliosis patients using non contrast computed tomographic (NCCT) scan.
Methods & Materials: This was a prospective observational study conducted in a tertiary care teaching hospital from January 2023 to June 2024 after obtaining approval from the institutional ethics committee. Informed written consent was recorded in all the cases. Children (age < 15 years) with scoliosis requiring surgery underwent a preoperative NCCT scan of spine on a 192 detector dual source scanner from cranio-vertebral junction to coccyx. The pedicle measurements performed for dorsal and lumbar vertebra and included Inner Pedicle Width (IPW), Outer Pedicle Width (OPW), Transverse Pedicle Angle (TPA) and Chord Length (CL. The measurements were done in accordance with previously published definitions by two experienced pediatric radiologists. One of the observers (observer 2) evaluated the scan twice after a minimum gap of 15 days for the purpose of evaluating intra observer variation. Pearsons’s correlation coefficient (r) was used to assess Inter observer and intra observer variations.
Results: 27 patients were enrolled in the study. However, one patient was excluded due to motion artifacts while another patient was excluded due to difficulty in ascertaining vertebral levels. Thus, 25 patients were included for statistical analysis.)The mean age of patients included was 11.28 ±2.82 years. Girls constituted 68% of the patient population. IPW measurements showed very strong positive correlation (r >0.9) for inter observer as well as intra observer variation. Similarly, OPW and TPA measurements showed very strong positive correlation for intra observer readings (r >0.9). For the inter observer variation, OPW and TPA showed strong to very strong correlation r value varying from >0.8 to >0.9. CL measurements showed very strong positive correlation for intra observer readings (r >0.9) and strong positive correlation (r >0.8) for inter observer readings.
Conclusions: The clinically relevant pedicle morphometric measurements on preoperative computed tomographic scan in children with scoliosis have strong to very strong inter observer and intra observer correlation. The study establishes reliability of such measurements using CT scan.