Sciatica

Sciatica refers to leg pain of a neuropathic origin, from the back down the posterior thigh and possible into the ankle.

MRI showing degenerative disc space at L5/S1

Subjective History:

Bilateral/ unilateral leg pain or paresthesia, in the posterior aspect of the leg. Buttock pain could also indicate nerve root pain.
It is essential to rule out symptoms of cauda equina syndrome -saddle anastheisa /paraesthesia and bladder bowel disturbance (loss of control, retention, hesitancy, urgency or a sense of incomplete evacuation)
Objective Examination:

Lumbar range of movement, reflexes, dermatomes, myotomes, straight leg raise.
Important to rule out other causes of leg symptoms e.g hip joint, vascular, spinal cord compression. Objective assessment to include hip rotation, Babinski, foot and ankle pulses.
References

Image from OpenI – Licensed by CC

Reassurance to patients that approximately 60% sciatica resolve < 6/52.
Prescribe Anti-neuropathic medications.
Physiotherapy for exercise, advice and guidance
If leg symptoms remain unchanged after 6/52, may be appropriate for BANS referral. Referrals BANS < 6/52 may be necessary for patients with h/o cancer or foot drop.
Patients with likely spinal central canal stenosis should usually undergo conservative treatment (physiotherapy and medications) prior to BANS pathway. Central canal stenosis usually found in older age groups with pain worsened by walking and standing, eased by leaning forwards, shopping trolley and sitting.
For sciatica which remains unchanged, nerve root block injections benefit the majority of patients with sciatica. For patients that do not improve following injections, surgery might be considered.
Injections are unlikely to benefit patients with central canal stenosis.
Injections/ operations are likely to improve buttock/ leg pain but may not improve low back pain
References

Image from OpenI – Licensed by CC