Lumbar Radiculopathy: Symptoms by Nerve Root, Causes and Treatment

01What

What is lumbar radiculopathy?

Radiculopathy means a problem with a nerve root. In the lumbar spine, the nerve roots L1 to L5 and the sacral roots S1 to S5 leave the spinal canal and form nerves that supply the legs. When a root is compressed or inflamed, people feel symptoms along its path, often more in the leg than the back. Sciatica is a common name for pain that follows the sciatic nerve, which is formed mainly from the L4 to S3 roots, so most cases of sciatica are lumbar radiculopathy.

02Roots

Symptoms by nerve root

• L4: pain in the front of the thigh, knee and inner shin; weakness straightening the knee; reduced knee reflex.
• L5: pain down the side of the leg to the top of the foot and big toe; numbness on top of the foot; weakness lifting the foot or big toe (foot drop in severe cases); difficulty walking on heels.
• S1: pain down the back of the thigh and calf to the sole and outer edge of the foot; weakness pushing up onto tiptoes; reduced ankle reflex.
• Symptoms often overlap, and imaging findings do not always match the pattern exactly.

03Causes

Causes

• Disc herniation: the most common cause, especially in people under 50.
• Foraminal stenosis: narrowing of the openings where nerve roots leave the spine.
• Lumbar spinal stenosis: narrowing of the central canal, causing leg symptoms on walking.
• Spondylolisthesis: one vertebra slipping forward on another.
• Degenerative changes such as bone spurs and thickened ligaments.
• Rarely: infection, tumours or cysts.

04Diagnosis

How it is diagnosed

Diagnosis is usually based on symptoms and examination, including testing strength, sensation and reflexes, and the straight leg raise test, in which lifting the straight leg reproduces leg pain. Imaging, usually MRI, is not needed for most people in the early weeks but is arranged if there are red flags, progressive weakness, or if symptoms persist and injections or surgery are being considered. Nerve conduction studies are sometimes used to clarify the diagnosis.

05Course

Natural course

For most people, radicular pain improves substantially over weeks to a few months. Many disc herniations shrink on their own. Numbness may take longer to resolve than pain, and some people have mild lasting sensory changes. Weakness usually improves as the nerve recovers, but progressive or severe weakness should be assessed quickly. Exercises suitable for disc-related radiculopathy are covered in herniated disc exercises.

06Treatment

Treatment

• Stay active: walking and gentle movement within comfort.
• Physiotherapy: exercises, nerve mobilisation and advice, as part of a package of care.
• Pain relief: NSAIDs where suitable; NICE advises against routinely using gabapentinoids, other antiepileptics, oral corticosteroids, benzodiazepines or opioids for chronic sciatica.
• Epidural steroid injections: may be considered for acute and severe sciatica.
• Surgery: decompression, such as microdiscectomy, for persistent severe symptoms or significant weakness.
• Psychological approaches as part of combined programmes for persistent pain.

07Exercises

Exercises that may help

• Walking, gradually increasing time.
• Prone lying and press-ups if they ease leg symptoms.
• Sciatic nerve glides, slow and gentle.
• Pelvic tilts and knee rocking.
• Glute bridges and core exercises as pain settles.
• Stretches for the buttocks and hamstrings if comfortable; see sciatica stretches.

08Stenosis

Radiculopathy from spinal stenosis

In older adults, nerve root symptoms are often caused by narrowing of the spine rather than a disc herniation. Symptoms typically come on with standing or walking and ease with sitting or bending forward, such as leaning on a shopping trolley. Treatment includes exercise, especially flexion-based exercises and cycling, physiotherapy, pain relief and, for severe cases, decompression surgery.

09Mimics

Conditions that can mimic radiculopathy

• Piriformis syndrome: buttock pain with leg symptoms; see piriformis syndrome.
• Hip joint problems, with groin pain.
• Peripheral neuropathy, usually affecting both feet.
• Peripheral arterial disease, with calf pain on walking.
• Sacroiliac joint pain.

10Cases

Three common situations

• Leg pain to the big toe after lifting: likely L5 radiculopathy from a disc; stay active and see a physiotherapist.
• New difficulty lifting the front of the foot: see a doctor promptly.
• Leg pain on walking that eases when sitting, in an older adult: may be spinal stenosis.

11Daily

Managing daily life with radiculopathy

• Change position often; avoid sitting for more than 20–30 minutes at a time.
• Use a pillow between the knees when sleeping on your side.
• Bend the knees and keep loads close when lifting.
• Return to work gradually, with adjustments if needed.
• Use heat or cold for comfort.
• Keep a simple diary of symptoms and activity to track progress.

12Summary

Key points to remember

• Lumbar radiculopathy is nerve root irritation in the lower back.
• Symptoms follow the nerve root pattern, such as L5 or S1.
• Most cases improve with activity and physiotherapy.
• Saddle numbness or bladder changes need emergency care.