Lumbar Radiculaopathy (Sciatica)
What is it: Herniation of the nucleus pulposus from a lumbar disk into the lumbar canal adjacent to an exiting lumbar nerve root resulting in compression and chemical irritation of the nerve. Most herniations occur at the L4-L5 and L5-S1 nerve levels.
How does it present: Patients will often present with an abrupt or insidious onset of low back pain associated with unilateral radiating leg pain or numbness or occasionally weakness. Pain is typically exacerbated by coughing and sneezing. In evaluating low back pain always look for red flag symptoms such as bowel or bladder incontinence, perineal anesthesia, unexplained weight loss or constitutional symptoms.
Common exam findings: Evaluate for limitations in trunk range of motion and spasm of lumbar paraspinous muscles. Straight Leg Raise is typically positive. Document motor/sensory function of the lumbosacral nerve roots as well as deep tendon reflexes.
Tests and treatment: L-S spine radiographs may show a decrease in the intervertebral spaces. MRI should be considered immediately if a neurologic deficit is identified or if further evaluation is needed due to persisting or unusual symptoms. Most symptoms from a lumber radiculopathy improve within the first six weeks with or without specific treatment. Treatment options include modification of aggravating activity, pain medications, ice/heat and physical therapy or home exercises for trunk strengthening. Suspected cauda equina syndrome necessitates emergent neurosurgical evaluation. Persistent radicular symptoms lasting longer than 6 weeks should also prompt further evaluation.