Cervical vertebrae measurements in syringomyelia.

Lateral X-rays of the cervical spine taken under standard conditions in 69 cases of syringomyelia have been measured to assess the relative sizes of the canals and bodies. One hundred and five cases without cervical spine abnormality provided controls. The expected expansion has been observed in males from C5 to C7 and in females from C3 to C7. The oddity that the expansive process seemed to come higher in females than in males has been noted by other workers. In both sexes it has been found that diminution of vertebral body size is a more consistent finding than enlargement of the canals and correlation coefficients have confirmed that enlargement of the canal appears to take place at least in part at the expense of the body. Possible factors in the enlargement are discussed. Oblique measurements taken in 57 syrinx cases and 89 controls showed the expected change caused by the view of the lower cervical vertebrae being closer to AP and pictures of the upper vertebrae being progressively closer to lateral views. There was a tendency for the bigger oblique diameters to occur in these cases with the biggest sagittal diameters and an insignificant tendency for the biggest canals to have a diminished difference between the two oblique measurements. There was no evidence that oblique measurements could be used to detect slight degrees of enlargement in cases of syringomyelia.