What are the Symptoms of S1 radiculopathy?
Here are the symptoms of S1 radiculopathy
- S1 root compression causes pain to radiate to the posterior buttock, posterior calf, and lateral foot (classic sciatica).
- Sensory loss occurs along the lateral aspect of the foot, especially in the third, fourth, and fifth toes.
- Weakness may occur in the gluteus maximus (hip flexor) and plantar flexors.
- The ankle jerk is usually diminished
Whereas denervation is typically associated with muscle tissue wasting, ipsilateral calf enlargement is an uncommon but well-recognized phenomenon associated with S1 radiculopathy.
The pathophysiology is unclear, but theories include muscle fiber hypertrophy of nondenervated muscle fibers, abnormal stretching of muscle fibers, and abnormal electrical activity.
EMG and lumbar spine imaging are helpful to confirm diagnosis of a radiculopathy. Surgical decompression has not been shown to result in resolution of hypertrophy.
If the first sacral nerve root is being compressed ― S1 radiculopathy ― the pain normally radiates down the back of the leg.
A case report of a 38-year-old woman presented with sudden onset radicular symptoms in her right lower extremity.
Lumbar magnetic resonance imaging demonstrated a right-sided L5-S1 extruded nucleus pulposus.
Her symptoms failed to improve after conservative management so she underwent surgical decompression of L4-S1.
Intraoperatively, it was discovered an extensive, extradural vascular malformation present at the L5-S1 level and believed this to be the true cause of her radiculopathy.
This case represents an atypical cause of lumbar radiculopathy and demonstrates the importance of considering atypical causes during diagnostic workup and preoperative planning.
