AN ASSESSMENT OF THE RELIABILITY OF THE SCOLIOMETER

Accurate noninvasive measurements of spinal curvature are crucial in p lanning treatment and assessing curve progression in adolescent idiopa thic scoliosis. An inter-rater agreement trial and an intrarater agree ment trial were undertaken to estimate the reliability of axial rotati on measurement using the Scoliometer (Orthopedic Systems, Inc., Haywoo d, California). In the inter-rater trial, two orthopedic surgeons and two orthopedic surgery residents independently measured the thoracic a nd lumbar axial rotations of 22 patients with idiopathic scoliosis usi ng the Scoliometer. In the intrarater, trial a single orthopedic surge on measured the thoracic and lumbar axial rotations of 25 patients on four separate occasions with the Scoliometer. Inter-rater agreement us ing the Scoliometer to estimate the magnitude of the hump (in centimet ers) in the thoracic and lumbar regions was poor (intraclass correlati on coefficient, Rho = 0.57 and Rho = 0.76 for the thoracic and lumbar regions, respectively). Inter-rater agreement using the Scoliometer to estimate the degree of axial trunk rotation was better (Rho = 0.81 an d Rho = 0.82 for the thoracic and lumbar regions, respectively). Intra rater agreement using this device to estimate the magnitude of the hum p (in centimeters) in the thoracic and lumbar regions was good (Rho = 0,90 and Rho = 0.84 for the thoracic and lumbar regions, respectively) . Intrarater agreement using the Scoliometer to estimate the degrees o f curvature was outstanding (Rho = 0.995 and Rho = 0.998 for the thora cic and lumbar regions, respectively). These results indicate that the Scoliometer can be a reliable noninvasive method for repetitively ass essing spinal axial rotation when used by a single trained observer.