Five pairs of lumbar nerve roots (L1–L5) exit through the intervertebral foramina at each level. These nerve roots join with the sacral nerve roots to form the lumbar plexus and sacral plexus, which supply the hips, thighs, knees, calves, feet, and toes. When a lumbar disc herniates or bone spurs narrow the foramen, nerve root compression causes lumbar radiculopathy — radiating pain, tingling, or weakness along the nerve’s distribution.

The most clinically significant is compression of the L4, L5, or S1 nerve roots, which form the sciatic nerve. Irritation of these roots causes the characteristic shooting pain from the lower back through the buttock and down the leg known as sciatica. At The Spine and Performance Institute in Edison, NJ, Dr. Sharan evaluates each patient’s specific nerve involvement to guide targeted treatment.

Dr. Alok Sharan is a Castle Connolly Top Doctor and NY Magazine Best Doctor with 20+ years of experience and 201 five-star Google reviews. Fellowship-trained at NYU Hospital for Joint Diseases and Deputy Editor of Clinical Spine Surgery, he has authored over 100 peer-reviewed publications on lumbar spine surgery outcomes. His practice at 35-37 Progress St., Suite B5, Edison, NJ 08820 serves patients throughout New Jersey and New York City.

Surgical options for lumbar spine conditions include:

Lumbar Spinal Fusion — stabilizes an unstable or painful lumbar segment by fusing adjacent vertebrae. Dr. Sharan performs lumbar fusion using his signature awake technique under regional anesthesia, enabling same-day discharge and a 2–4 week recovery for most patients versus the traditional 6–12 weeks.

Laminectomy / Discectomy — decompression surgery removing a herniated disc fragment or lamina pressing on nerve roots. Minimally invasive approaches use small incisions to preserve surrounding muscle and speed recovery.

Minimally Invasive TLIF / XLIF / ALIF — advanced fusion techniques accessing the disc from the side (XLIF/ALIF) or back (TLIF), offering less tissue disruption. Dr. Sharan evaluates each patient’s anatomy to determine the optimal approach.

Why is L4–L5 and L5–S1 so commonly affected?

These two levels account for the vast majority of lumbar disc herniations and stenosis because they bear the greatest mechanical load and experience the most motion. L4–L5 compression typically affects the L4 or L5 nerve root, causing pain into the foot or big toe. L5–S1 compression often involves the S1 nerve root, causing pain into the heel and outer foot.

What is the difference between a bulging disc and a herniated disc?

A bulging disc extends beyond the normal disc boundary but the outer layer (annulus fibrosus) remains intact. A herniated disc involves a tear or rupture in the outer layer, allowing the inner nucleus pulposus to protrude and potentially contact nearby nerves. Both can cause sciatica or a pinched nerve, but herniations often cause more acute symptoms.

What is spinal stenosis and what causes it?

Lumbar spinal stenosis is a narrowing of the spinal canal that compresses the nerve roots running through it. It is most commonly caused by degenerative changes: bulging discs, thickened ligamentum flavum, and enlarged facet joints. Symptoms include leg pain, numbness, and weakness that worsens with walking and improves with sitting (neurogenic claudication).

Is awake lumbar fusion really possible?

Yes — Dr. Sharan has pioneered awake lumbar spinal fusion using regional anesthesia, meaning many patients are conscious or lightly sedated rather than under general anesthesia. This reduces anesthesia risk, speeds recovery to 2–4 weeks, allows same-day discharge, and minimizes opioid use. Call (732) 898-3950 to find out if you’re a candidate.