On Cervical Mobility

Abstract

The mobility of healthy unfixed specimens of human cervical spines in the sagittal plane varied between 65[degree] and 110[degree] when subjected to a static load of 4 kg. The variation in mobility was attributed to differences in the extensibility of the controlling ligaments. The extensibility of the ligamenta-flava which varied considerably was positively correlated with the overall mobility of the spine from which it was derived. The distribution of cervical movement followed a regular pattern. Disc degeneration was associated with progessive restriction of movement at the affected level. Segmental immobilization was not associated with increased mobility of the unaffected parts but the latter may be exposed to excessive stress through attempts to increase the range because of the overall reduction in the range of movement in the neck.