The lumbar spine is the lower section of the backbone. Its vertebrae stack around a central canal, with discs between the bones and joints and ligaments helping connect them. Nerve roots travel from the spinal canal towards openings between vertebrae, carrying signals for movement and sensation. In adults the spinal cord ends above the lower lumbar canal; below it, a bundle of nerve roots called the cauda equina continues downwards.

Nerve roots contribute to signals to and from the legs. Roots in the cauda equina also supply bladder and bowel function and feeling around the genitals and bottom. A disc protrusion, thickened tissue or bony change can reduce space in the canal or where a root exits. Pressure or irritation can produce pain, altered sensation or weakness in the area supplied by the affected nerve.

Stenosis means narrowing. Narrowing in the central canal is different from narrowing around a nerve exit, sometimes called a foramen. Imaging can show these changes, but narrowing can also be present without symptoms. The history, examination and scan need to fit together before a surgeon can say which level and side might be responsible.

Sciatica describes pain associated with irritation or compression of the sciatic nerve, usually in the buttock and down one leg, sometimes to the foot and toes. Tingling, numbness or weakness can accompany it. A disc protrusion is one possible cause; stenosis and a slipped vertebra are others. Back pain alone is not usually sciatica, and leg symptoms do not identify their cause without an assessment.

Lumbar stenosis can cause leg pain, numbness or weakness with standing and walking. This pattern is called neurogenic or spinal claudication. The point at which symptoms start, the distance you can walk and what relieves them are useful details to record. Back pain may occur too, but decompression for sciatica or stenosis is generally more reliable for leg pain than for back pain.

A scan showing a disc change does not automatically prove that it is the source of every symptom. Clinicians consider how pain travels, strength, sensation and other examination findings alongside imaging. New or changed symptoms can also have other causes, including infection, injury, inflammatory disease or cancer. Tell the clinician what has changed rather than assuming it is the same back problem.

For planned care, the decision starts with the symptom that matters most: perhaps walking to the shops, sleeping or returning to work. Non-surgical care can include advice to remain active within your capabilities, a tailored exercise programme or physiotherapy, and a review of pain medicines. Some episodes of sciatica improve without surgery. Ask what improvement is realistic, how the plan will be reviewed and what should prompt earlier reassessment.

For sciatica, NICE recommends considering decompression when non-surgical treatment has not improved pain or function and imaging findings match the sciatic symptoms. NICE says an epidural containing local anaesthetic and steroid can be considered for acute severe sciatica, but should not be used for neurogenic claudication from central canal stenosis. An injection and surgery have different aims and risks; neither is suitable for every presentation.

Medicines also need an individual discussion. NICE advises against offering gabapentinoids, other antiepileptics, oral corticosteroids or benzodiazepines for sciatica, and against opioids for chronic sciatica, because of the evidence of benefit and harm. If you already take one, discuss the risks and a safe review with your prescriber. Do not stop a prescribed medicine abruptly on the basis of this guide.

An elective choice is different from suspected cauda equina syndrome, which needs emergency assessment. For a planned operation, ask what can happen with continued non-operative care, how long a decision can reasonably wait in your circumstances and which changes require urgent help. Explain your priorities and ask about benefits and complications in people with a similar diagnosis and health.

The aim is to make more room for the affected nerves. In a laminectomy, a surgeon removes some bone at the back of a vertebra. Depending on where the narrowing is, the surgeon may also remove tissue or undercut part of a facet joint. A discectomy removes a portion of disc material pressing on a nerve, not necessarily the whole disc. Some people need a combination of techniques at one or more levels.

A microdiscectomy uses a microscope to help the surgeon work on a disc; a smaller-incision approach is also possible for some decompressions. Ask which level and side will be treated, which structures will be removed and why that approach fits your scan and symptoms. The operation makes space; it does not replace the spine, reverse all age-related changes or guarantee that an irritated nerve will fully recover.

Fusion is a separate decision: it joins vertebrae, often with bone graft and metal instrumentation, to limit movement at the treated segment. A surgeon may discuss it in selected situations involving a slipped vertebra or concerns about stability. It is not automatically part of decompression. NICE advises against offering fusion for low back pain unless within a randomised controlled trial; that recommendation should not be treated as a rule for every other spinal diagnosis.

A US randomised trial compared decompression with a structured physical therapy programme in surgical candidates aged 50 or over with symptomatic lumbar stenosis. At two years the assigned groups did not show a clear difference in physical function. Many people assigned to physical therapy crossed over to surgery, making the treatments difficult to separate; the study does not prove they are identical or predict an individual outcome.

In the Norwegian Nordsten-DS trial, adults with symptomatic stenosis and degenerative spondylolisthesis were assigned decompression alone or decompression plus instrumented fusion. At five years, decompression alone met the trial’s predefined non-inferiority criterion for improvement in a disability score. This applies to the studied group and outcome, not every cause of instability or every person considering spine surgery. Discuss why fusion is or is not proposed for your particular spine.

Pre-operative assessment checks your health, medicines and fitness for anaesthesia; blood tests or other checks may be needed. Bring a complete list of prescribed medicines, over-the-counter products and supplements, and mention blood thinners, allergies, previous operations and any previous anaesthetic problems. Ask exactly what to continue, pause and restart. Follow your hospital’s own eating and drinking instructions.

Discuss realistic steps to prepare, such as activity within your ability, nutrition and support to stop smoking. Plan transport home, help with shopping and personal care, and a way to manage stairs or caring duties. Ask what to do if you become unwell or your neurological symptoms change while waiting. You should have a chance to understand the proposed benefits, risks and alternatives before consenting.

Lumbar decompression is usually performed under general anaesthetic, so you are asleep. The team positions you face down on a special support and monitors you throughout. The surgeon makes an incision or, for some approaches, smaller cuts in the back, reaches the planned level and removes the bone or tissue causing compression. X-rays may be used during the operation to check the level.

The wound is closed with stitches or clips, which may be dissolvable or need removal later. In recovery, staff monitor you and give pain relief. A drip, a temporary bladder catheter or a wound drain may be used. Ask afterwards what was done, whether the planned level was treated and whether anything occurred that changes your recovery instructions.

The intended benefit is relief of nerve-related leg symptoms or improvement in walking and function. Leg pain may improve, but numbness or weakness can persist, and back pain may not improve. Recovery is not always immediate. Surgery cannot guarantee a particular result, and symptoms may return. Ask the surgeon which of your symptoms are likely to respond and which may have another cause.

A dural tear is an opening in the membrane around the nerves and spinal fluid. It can cause spinal fluid to leak. Depending on the tear, the surgeon may repair it with stitches or a patch or use another approach; persistent leakage may need further treatment or surgery. A leaking wound, especially with headache or temperature, needs urgent assessment as described above.

Other risks include infection, bleeding, blood clots in a leg or lung, and nerve injury that can cause pain, weakness or numbness. Rare serious harm can include cauda equina syndrome or paralysis. A vertebra may become unstable after decompression, and further surgery can sometimes be needed. Anaesthetic and general medical complications also depend on your health and the planned operation.

A return of symptoms can have different explanations, including further narrowing, a recurrent disc problem or scar tissue. It does not automatically mean that another operation is needed. Ask for assessment of the new pattern and compare it with your symptoms before surgery. The cause, your examination and any appropriate imaging guide what happens next.

The team usually helps you get up and move as soon as possible, sometimes on the day of surgery or the next day. Physiotherapists may check walking, stairs and exercises before discharge. Hospital stay depends on the procedure and your health. Before leaving, ask for written guidance on wound care, medicines, activity restrictions, follow-up and a contact number for concerns.

Expect some wound and back soreness and fatigue. Take pain relief as prescribed and discuss constipation or side effects with the team or pharmacist. Follow your own dressing and washing instructions, because local plans vary. Increasing walking gradually and taking regular rests can help you rebuild activity; follow the team’s advice about bending, twisting, heavy lifting and more strenuous exercise.

NHS England says some people can return to work in around four to six weeks, depending on the job and clinical advice; usual activities may take up to 12 weeks. Physical work, a more complex operation or complications can take longer. Driving requires being free of medicines that make you drowsy, being comfortable in the driving position and able to perform an emergency stop safely. Check your team’s advice and your insurer.

Leg pain and walking may improve gradually over the first few months, and some improvement can continue longer. Follow-up arrangements vary: confirm the date, who to contact if it does not arrive and whether physiotherapy or occupational therapy is appropriate. Describe any remaining weakness, numbness, bladder or bowel symptoms, and whether everyday activities have improved. Do not wait for routine follow-up if urgent warning signs occur.

Longer term, ask for an activity and exercise plan that fits your capacity and goals. Ongoing or returning pain should be assessed rather than assumed to mean the operation has failed. If leg weakness, walking difficulty or uncertainty about movement continues, ask whether rehabilitation or another review would help. Your surgical report and discharge letter can help future clinicians understand what was done.