In order to evaluate the effectiveness of the Mobi-C implant
in cervical disc degeneration, a randomised study was conducted,
comparing the Mobi-C prosthesis arthroplasty with anterior cervical
disc fusion (ACDF) in patients with single level cervical spondylosis. From January 2008 to July 2009, 99 patients were enrolled and
randomly divided into two groups, those having a Mobi-C implant
(n = 51; 30 men, 21 women) and those undergoing ACDF (n = 48; 28
men, 20 women).The patients were followed up for five years, with
the primary outcomes being the Japanese Orthopaedic Association
score, visual analogue scale for pain and the incidence of further
surgery. The secondary outcomes were the Neck Disability Index and
range of movement (ROM) of the treated segment.Aims
Patients and Methods
Discogenic low back pain is a common cause of disability, but its pathogenesis is poorly understood. We collected 19 specimens of lumbar intervertebral discs from 17 patients with discogenic low back pain during posterior lumbar interbody fusion, 12 from physiologically ageing discs and ten from normal control discs. We investigated the histological features and assessed the immunoreactive activity of neurofilament (NF200) and neuropeptides such as substance P (SP) and vasoactive-intestinal peptide (VIP) in the nerve fibres. The distinct histological characteristic of the painful disc was the formation of a zone of vascularised granulation tissue from the nucleus pulposus to the outer part of the annulus fibrosus along the edges of the fissures. SP-, NF- and VIP-immunoreactive nerve fibres in the painful discs were more extensive than in the control discs. Growth of nerves deep into the annulus fibrosus and nucleus pulposus was observed mainly along the zone of granulation tissue in the painful discs. This suggests that the zone of granulation tissue with extensive innervation along the tears in the posterior part of the painful disc may be responsible for causing the pain of discography and of discogenic low back pain.