Computed tomographic evaluation of C5 root exit foramen in patients with cervical spondylotic myelopathy.

BACKGROUND

Narrowing of the intervertebral foramen for C5 root and a larger superior articular process in myelopathic patients with postlaminoplasty motor dominant C5 radiculopathy has been reported. We investigated whether the C4-5 foraminal dimensions and surface area in patients with cervical spondylotic myelopathy are universally smaller than the intervertebral foramina at other cervical levels.

METHODS

The study population consisted of 44 consecutive patients (sex: 24 males and 20 females), averaging 55.7 years of age (range 42-84) years who presented with clinical features suggestive of cervical spondylotic myelopathy. Using computed tomography (CT) imaging, we prospectively compared height, transverse diameter, and surface area of the C4-5 foramen to those of C3-4, C5-6 and C6-7 foramina of the same side in the whole study population as well as in male and female patients.

RESULTS

In the whole study population at C4-5 intervertebral foramen the mean foraminal height was 8.37 ± 1.3 mm on the right and 8.85 ± 1.16 mm on the left; and the mean foraminal transverse diameter on the right was 4.97 ± 1.35 mm and 5.14 ± 1.16 mm on the left. No statistically significant difference was found between the measurements in the whole study population at various levels, between or within male and female patient groups.

CONCLUSION

C4-5 intervertebral foramen is not uniformly smaller in patients with cervical spondylotic myelopathy.