Cervical spondylosis is defined as chronic disc degeneration and associated facet arthropathy that can lead to the following clinical conditions
cervical radiculopathy
cervical myelopathy
discogenic neck pain
Epidemiology
cervical spondylosis typically begins at age 40-50
most common levels are C5-6 > C6-7 because they are associated with the most flexion and extension in the subaxial spine
more common in men than women
Risk factors include
excessive driving
smoking
lifting
professional athletes
Pathoanatomy
Spondylosis is a natural aging process of the spine
characterized by degeneration of the disc and the four joints of the cervical motion segment which include
two facet joints
two uncovertebral joints of Luschka)
Degenerative cycle includes
disc degeneration
disc dessication, loss of disc height, disc bulging, and possible disc hernaition
joint degeneration
uncinate spurring and facet arthrosis
ligamentous changes
ligamentum flavum thickening and infolding secodary to loss of disc height
deformity
kyphosis secondary to loss of disc height with resulting transfer of load to the facet and uncovertebral joints, leading to further uncinate spurring and facet arthrosis
Mechanism of Neurologic Compression
Nerve root compression (radiculopathy) caused by
foraminal spondylotic changes
secondary to chondrosseous spurs of facet and uncovertebral joints
posterolateral disc herniation
between posterior edge of uncinate and lateral edge of PL
usually affects the nerve root below (C6/7 disease will affect the C7 nerve root)
Central cord compression (myelopathy)
occurs with canal diameter is < 13mm (normal is 17mm)
worse during neck extension whe central cord is pinched between
degenerative disc (anterior)
hypertrophic facets and infolded ligamentum (posterior)
in asians can be caused by ossification of the posterior longitudinal ligament
Evaluation
Radiographs
common radiographic findings include
degenerative changes of uncovertebral and facet joints
osteophyte formation
disc space narrowing
endplate sclerosis
decreased sagital diameter (cord compression occurs with canal diameter is < 13mm)
changes often do not correlate with symptoms
70% of patients by 70 yrs of age will have degenerative changes seen on plain xrays
lateral
important to look for sagital alignment and size of spinal canal
oblique
important to look for foraminal stenosis which often caused by uncovertebral joint arthrosis
flexion and extension views
important to look for angular or translational instability
look for compensatory subluxation above or below the spondylotic/stiff segment
MRI
axial imaging is the modality of choice and gives needed information on the status of the soft tissues. It may show
disc degeneration
spinal cord changes (myelomalacia)
preoperative planning
has high rate of false positive (28% greater than 40 will have findings of HNP or foraminal stenosis)
CT myelography
can give useful information on bony anatomy
most useful when combined with intrathecal injection of contrast (myelography) to see status of neural elements
contrast given via C1-C2 puncture and allowed to diffuse caudally or given via a lumbar puncture and allowed to diffuse proximally by putting patient in trendelenburg position.
paricularly useful in patients that can not have an MRI (pacemaker) or has artifact (local hardware)
Discography
controversial and rarely indicated in cervical spondylosis
approach is similar to that used with ACDF
risks include esophageal puncture and disc infection
Nerve conduction studies
high false negative rate
may be useful to distinguish peripheral from central process (ALS)
(SBQ07.30) Prospective studies have shown professional athletes in which of the following sports have the highest incidence of degenerative changes in the cervical and lumbar spine? Review Topic
Professional horse racers (Jockeys) have the highest incidence of degenerative changes of both the cervical and lumbar spine when compared to age-matched, non-athletes.
There is significant risk of injury when working with horses. The most common acute injuries are extremity fractures from falls off of the horse. Chronic injuries are also well known with a high incidence of degenerative changes of the spine, most commonly in the cervical and lumbar spine.
Tsirikos et al. performed a prospective study analyzing the long-term effects of horse riding on the cervical and lumbar spine in jockeys. A 13-year clinical follow-up of the 32 jockeys revealed the following: 15 (47%) jockeys reported mild to severe limitations of physical activities as a consequence of progressive degenerative changes of the spine. Twenty-four (75%) jockeys had degenerative lesions on the cervical and/or lumbar spine radiographs compared to 6 (18%) in the control group.
Cowley et al. reviewed the workers compensation claims for injuries sustained by horse racing professionals. Of the 358 horse-related injuries sustained by jockeys, 270 (75%) were associated with falls from a horse. They showed that fractures were the most common injury, with the leg and shoulder being the most common sites. There was no comment about long-term chronic injuries.
Illustration A shows a schematic representation of the spinal degenerative process. From left to right there is progressive loss of disc height and osteophyte formation.
Incorrect Answers: Answers 2,3,4,5: None of the sports listed have been shown to have higher rates of degenerative spine problems than jockeys. The sports most commonly cited as having the greatest strain on the spine include: horse-racing, wrestling, rugby, ski-jumping, and gymnastics.
1. Tsirikos A, Papagelopoulos PJ, Giannakopoulos PN, Boscainos PJ, Zoubos AB, Kasseta M, Nikiforidis PA, Korres DS. Degenerative spondyloarthropathy of the cervical and lumbar spine in jockeys. Orthopedics. 2001 Jun;24(6):561-4. PubMed PMID: 11430735. PMID:11430735 (Link to Abstract)
2. Cowley S, Bowman B, Lawrance M. Injuries in the Victorian thoroughbred racing industry. Br J Sports Med. 2007 Oct;41(10):639-43; discussion 643. Epub 2007 May 14. Review PMID:17502333 (Link to Abstract)
Review Topic 
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