Evaluation of Cervical Spondylosis by Cervical MRI in Patients with Amyotrophic Lateral Sclerosis

ABSTRACT

BACKGROUND: Amyotrophic lateral sclerosis (ALS) is a progressive degenerative disease involving upper and lower motor neurons, which leads to respiratory paralysis and death. Although ALS has been well known to be combined with cervical spondylosis, its frequency has not been established. The purpose of this study is to investigate the frequency of the cervical spondylosis in patients with ALS. METHODS: We evaluated the frequency and degree of spinal stenosis in ALS patients using cervical MRI. The study groups were composed of 30 ALS patients and 30 healthy controls. Using the T2-weighted cervical MRI, we measured the anteroposterior diameters of the cord and canal in the sagittal and axial views at the narrowest and C3-4 levels, and calculated the ratios of cord/canal (CCr). We also measured the areas of the cord and canal in the axial views at the narrowest and C3-4 levels. RESULTS: Of the 30 patients, 20 (66.7%) had cervical spondylosis. On sagittal and axial view, the average CCr at the narrowest / C3-4 level were 71.2 +/- 10.4 / 67.8 +/- 9.6% and 73.1 +/- 9.3 / 71.3 +/- 8.2% in ALS, and 59.2 +/- 4.4 / 56.7 +/- 5.9% and 62.5 +/- 5.6 / 60.4 +/- 6.4% in controls. The area of spinal cord at the narrowest / C3-4 level was 69.1 +/- 9.8 / 70.3 +/- 8.7 mm2 in ALS, and 78.4 +/- 11.3 / 78.9 +/- 10.8 mm2 in controls. The area of canal at the narrowest / C3-4 level was 149.7 +/- 12.5 / 151.5 +/- 7.8 mm2 in ALS, and 172.5 +/- 12.5 / 173.8 +/- 11.6 mm2 in controls. CONCLUSIONS: Our results showed the high frequency of cervical spondylosis and spinal cord atrophy in ALS.