Torg Ratio In Normal Ageing Population: No Risk of Stenosis

Canal/body or Torg’s ratio has been agreed as a reliable method to detect cervical spinal stenosis. Age changes of cervical canal diameter and the ratio have been seldom analyzed in the cohort of normal adults. Our objective is to undertake the age changes in decades from healthy young to the elderly subjects. Sagittal diameter (SD) of the spinal canal and anteroposterior diameter of the vertebral body (VB) were taken on the lateral cervical radiographs consisting of normal appearance from 104 males and 102 females. SD showed significant gender differences and insignificant age changes. VB changed with age significantly in both sex, and showed sex difference. Torg ratio was found above 0.9 and changed with age. The ratio also indicated no difference between sexes. The male/female difference declared previously might not be a consistent finding. The present study suggested that bone cervical canal might diminish in normal ageing persons without existence of the cervical stenosis and/or risk of myelopathy. Our findings might be peculiar to our subject group, which need to be confirmed by the further studies.

PDF

___

1. Tierney RT, Maldjian C, Mattacola CG, Straub SJ, Sitler MR. Cervical Spine Stenosis Measures in Normal Subjects. J Athl Train. 2002; 37: 190–193.
2. Torg JS, Corcoran TA, Thibault LE, et al. Cervical cord neurapraxia:classification, pathomechanics, morbidity, and management guidelines.Neurosurg. 1997; 87: 843-850.
3. Inoue H, Ohmori K, Takatsu T, Teramoto T, Ishida Y, Suzuki K. Morphological analysis of the cervical spinal canal, dural tube and spinal cord in normal individuals using CT myelography. Neuroradiology 1996; 38: 148-151.
4. asaki T, Kadoya S, Iizuka H. Roentgenological study of the sagittal diameter of the cervical spinal canal in normal adult Japanese. Neurol Med Chir (Tokyo) 1998; 38: 83-89.
5. Senol U, Cubuk M, Sindel M, et al. Anteroposterior diameter of the vertebral canal in cervical region: comparison of anatomical, computed tomographic, and plain film measurements. Clin Anat 2001; 14: 15-18.
6. Stanley JH, Schabel SI, Frey GD, Hungerford GD. Quantitative analysis of the cervical spinal canal by computed tomography. Neuroradiology 1986; 28: 139-143.
7. Torg JS, Pavlov H, Genuario SE, et al. Neurapraxia of the cervical spinal cord with transient quadriplegia. J Bone Joint Surg (Am) 1986; 68: 1354-1370.
8. Lim JK, Wong HK. Variation of the cervical spinal Torg ratio with gender and ethnicity. Spine. J 2004; 4: 396-401.
9. Torg JS, Naranja RJ Jr, Pavlov H, Galinat BJ, Warren R, Stine RA. The relationship of developmental narrowing of the cervical spinal canal to reversible and irreversible injury of the cervical spinal cord in football players. J Bone Joint Surg (Am) 1996; 78: 1308-1314.
10. Tanaka Y. Morphological changes of the cervical spinal canal and cord due to aging. J Jpn Orthop Assoc 1984; 58: 873-886.
11. Lee HM, Kim NH, Kim HJ, Chung IH. Midsagittal canal diameter and vertebral body/canal ratio of the cervical spine in Koreans. Yonsei Med J 1994; 35: 446-452.
12. Ishikawa M, Matsumoto M, Fujimura Y, Chiba K, Toyama Y. Changes of cervical spinal cord and cervical spinal canal with age in asymptomatic subjects. Spinal Cord 2003; 41: 159-163.
13. Eismont FJ, Clifford S, Goldberg M, Green B. Cervical sagittal spinal canal size in spine injury. Spine 1984; 9: 663-666.
14. Gore DR, Sepic SB, Gardner GM. Roentgenographic findings of the cervical spine in asymptomatic people. Spine 1986; 11: 521-524.
15. Herzog RJ, Wiens JJ, Dillingham MF, Sontag MJ. Normal cervical spine morphometry and cervical spinal stenosis in asymptomatic professional football players. Plain film radiography, multiplanar computed tomography, and magnetic resonance imaging. Spine 1991; 16: 178-186.
16. Ezra D, Slon V, Kedar E, et al. The Torg Ratio of C3-C7 in African Americans and European Americans: A Skeletal Study. Clinical Anatomy 2019; 32: 84-89.
17. Robinson MD, Northrup B, Sabo R. Cervical spinal canal plasticity in children as determined by the vertebral body ratio technique. Spine. 1990; 15: 1003-1005.
18. Kar M, Bhaumik D, Ishore K, Saha PK. MRI Study on Spinal Canal Morphometry: An Indian Study. Journal of clinical and Diagnostic Research 2017; 11: 8-11.
19. Pavlov H, Torg JS, Robie B, Jahre C. Cervical spinal stenosis: determination with vertebral body ratio method. Radiology 1987; 164: 771-775.
20. Hukuda S, Kojima Y. Sex discrepancy in the canal/body ratio of the cervical spine implicating the prevalence of cervical myelopathy in men. Spine 2002; 27: 250-253.
21. Rijal B, Pokharel RK, Paudel S, Shah LL. Torg’s Ratio in Normal Adult Nepalese Population. Journal of Society of Surgeons of Nepal 2015; 18: 5-9.