Back Pain after a Road Traffic Accident

Normal looking disc with Low Back Pain

History

• 38 year old involved in a car accident 3 years ago• Hit from behind.• Gradual onset Low Back Pain- no leg pain• Got progressively worse• Not working for 2 years – senior managment position• Tried phsyio and exercise- made it worse• Depressed• Litigation ongoing.• Pain worse on sitting. Sleep disturbed.• On regular opiate pain killers

Examination

• Tender L5-S1 segment• Flexion- limited by 50%. Extension normal.• No sacro-iliac joint tenderness• SLR normal• No neurodeficit in legs• Looks depressed

Narrowed disc height L5/S1. No degeneration on MRI scan. Tender L5/S1.

What is the cause of her pain?MRI reported as showing a normal signal at the L5/S1 level

Initial Rx: Facet Joint injections

Had 3 sets of lumbar facet joint injections. Each provided pain relief for 2-3 months only.Also had physiotherapy for 12 months.No better. Still off work, in pain and depressed. Job under threat.

What should we do now?

Discogram L5/S1- painful disc- reproduced concordant back pain

Needle inserted into the disc under sedationInjected with onmipaque dye and local anesthetic

L5/S1 Posterior Lumbar interbody fusion 12m ago

Pain free 12m from surgeryNo more pain killersDepression goneBack to work full time

Claim not yet settled

Learning Points

• MRI scans do not show internal tears in disc or small haematomas. They also do not reveal concentration of inflammatory chemicals in the disc space

• A normal MRI scan does not equal a normal or ‘lying’ patient

• Patients with ongoing litigation are usually honest and in genuine pain

ANNULAR TEARAT L4.MRI HERE MAY LOOK NORMAL

Learning points

• Road traffic accidents can cause muscular strains, sacro-iliac sprains or disc and facet injuries

• Principle of surgery is to remove the pain source( disc, facet joint), and restore normal loading across the disc

• Important to chase the pain generator and treat patients and not write them off if investigations are ‘Normal’