Influence of age on cervicothoracic spinal curvature: an ex vivo radiographic survey.

OBJECTIVE

To define the post-mortem cervicothoracic spinal curvature relative to age.

DESIGN

Spinal curvature assessment of lateral cervicothoracic radiographs.

BACKGROUND

A late consequence of age is the progressive accentuation of spinal curvatures, particularly the thoracic kyphosis. Little is known about the influence of the kyphosis on the alignment of the cervical spine.

METHOD

One hundred and seventy two lateral spinal radiographs (113 males, 59 females) were analysed using two procedures: (1) sagittal curve deformation angles were derived, according to the method of Cobb, for thoracic (T1-T12), cervical (C2-C7) and cervicothoracic junctional regions (C6-T4); and (2) the cervicothoracic curvatures were digitised (C2-T12), to derive the apex of both curves and the inflexion point.

RESULTS

A significantly increasing thoracic spinal curvature was determined for both genders, with the mean apex of the kyphosis close to T6. The cervical lordosis tended to flatten with increasing age, particularly in males, with the cervical apex location shifting cranially. This association was significant in older males and females. The mean location of the cervicothoracic curve inflexion point moved from T3 towards C7-T1 with increasing age.

CONCLUSION

The cervicothoracic spinal curvature undergoes progressive change through the lifespan with a subsequent cranial migration of the inflexion point between the thoracic kyphosis and cervical lordosis, accompanied by a similar shift in the cervical apex.

RELEVANCE

Sensitive measures of spinal curvature have utility in determining changes attributed to age, deformity or trauma on cervicothoracic spinal alignment. The value of assessing the location of curve inflexion lies in the ability to quantify changes in the relationship between different regions of the human spine without problems associated with identifying specific vertebral landmarks.