Cauda equina are multiple nerve roots beginning at the level of L1
Most common injury is posterolateral disc herniation.
this causes pressure on the nerve root which can cause changes to sensory, motor and reflexes.
Under these circumstances the straight leg raise will be positive.
In contrast central disc herniation can cause cauda equina syndrome. Compression over the central nerve roots will cause more back pain than leg pain. The bladder and bowel may be affected and this is considered a surgical emergency.
Age is a risk factor as the discs degenerate. A history of trauma or cancers maybe important.
- severe back pain
- saddle anaesthesia
- bladder and bowel dysfunction
- absent anal reflex
- gait disturbance.
- erectile dysfunction
- reduced or absent deep tendon reflexes
- reduced lower extremity strength
- reduced sensation over lower extremities.
- reduced or absent cremasteric reflex.