L-Spine

Question 1

You suspect a sero-negative inflammatory arthritic condition which may present in young males. Name the condition you suspect.

Answer 1

Ankylosing Spondylitis

Question 2

State the distinguishing pathological features of Ankylosing Spondylitis.

Answer 2

Bilateral sacroilitis. Ascending spinal involvement. Thoraco-lumbar region. Lumbo-sacral region. Costo-vertebral joints. Large synovial joints maybe involved. Not well understood. Immune response. HLA-B27 antigen present in 90%. Increase in susceptibility following infection. Involves the synovium, cartilage and entheses (bone-ligament or bone-tendon junction).

Question 3

You are required to x ray the lumbar spine and pelvis. Describe the radiographic findings you might expect to see in the sacro iliac joints and spine if Akylosing Spondylitis is present.

Answer 3

SACROILIAC JOINT: Bilateral and Symmetrical. Lower 2/3 of joint involved. Reactive sclerosis mainly on the ilium side of the joint. SPINE: Discovertebral junction. “Squared” vertebra on lateral film. “Barrel shaped” on lateral film. “Bamboo spine” on AP film.

Question 4

Differentiate Ankylosing Spondylitis from a degenerative condition by describing the radiographic features of osteoarthritis in the vertebral bodies and articular facet joints of the spine.

Answer 4

IVD/Vertebral body: Asymmetrical distribution. loss of height. Osteophytes. Subchondral sclerosis. Canal stenosis. Articular facet joint: Deformity/osteophytes. Subluxation. IVF encroachment & Sclerosis.

Question 5

Outline the structure of an intervertebral disc.

Answer 5

Annulus Fibrosis (AF). Nucleus Pulposus (NP). Connects vertebral bodies.

Question 6

Describe the aetiological pathology of a prolapsed disc.

Answer 6

Degenerative changes trauma or increased pressure may rupture the annulus fibrosus - usually at its weakest spot - the posterior aspect where it is the thinnest and where the posterior longitudinal ligament is the weakest. With increased pressure transmitted through the spine the nucleus pulposus will then herniate postero-lateral or posteriorly. Compressing on the roots of the spinal nerves or directly on the spinal cord.