OBJECTIVE: Cervical spondylotic myelopathy (SCM) is a dysfunction related to spinal cord degeneration typical of aging. In the imaging studies can achieve a measure of the Torg index to estimate cervical stenosis. We aim therefore to measure the Torg index in X-rays and Magnetic Resonance (MR), to investigate possible discrepancies between the methods of measurement. METHODS: The Torg Index was measured on radiographs and MR of the cervical spine, obtained by determining the relationship between the posterior surface of the vertebral body and the nearest point to the corresponding laminar line, divided by the sagittal diameter of vertebral body. RESULTS: A total 29 patients has participated, 10 women and 19 men, with mean age of 48.1 ± 11 years, weight 68.7 ± 5kg and height 1.68 ± 0.6m. There were significant differences between the Torg Index calculated by radiography and MR, and lower rates observed on MR (radiography: 0.73 ± 0.17 vs. RM: 0.48 ± 0.14, p <0.05). However, both measurements reflect the same result: absolute cervical stenosis (Torg index < 0.8). CONCLUSIONS: Our results confirm reports by other authors who believe that the Torg Index measured by radiography, as recommended, minimizes the actual cervical canal stenosis. Our study suggests that MRI allows better estimate of the degree of stenosis, although our results regarding the degree of cervical stenosis were statistically similar.
Spine; Spinal diseases; Radiology; Radiography; Magnetic resonance imaging