What is Laminectomy?

Introduction

In simple terms, a laminectomy is when a small part of one of your spinal bones (vertebra) is removed to relieve pressure on nearby nerves.¹

Often as we age, degenerative changes occur in the spine, leading to a condition known as spinal stenosis (narrowing of the spaces within the vertebrae). Spinal stenosis may also be caused by tumours, injuries or congenital abnormalities at a younger age.¹ 

Symptoms are not always present, however, when the narrowed spaces squeeze the enclosed nerves, you might experience pain, numbness and tingling in the lower back, neck and/or legs. In most cases, non-surgical treatment (e.g. physiotherapy) and medication will improve symptoms. When these treatments have not helped and your quality of life is severely impacted, a laminectomy is then recommended.

The general goal of a laminectomy is to give the compressed nerves extra space so that they no longer feel squeezed whilst maintaining as much strength and flexibility of the spine as possible. By relieving the pressure, pain and other symptoms are drastically reduced and your mobility should also improve. The affected nerves are also provided a better environment to heal from the previous compression.¹ 

Understanding spinal anatomy 

A good grounding of spinal anatomy will set you up well to better understand a laminectomy.^2,4 

Our spine, or backbone, is made up of several small bones (vertebrae) stacked on top of each other – with muscles, ligaments and discs as supporting structures. Its primary function is to enclose and protect the spinal cord, as well as provide postural stability and flexibility.

Vertebrae

Each vertebral bone has the same essential structure (with a few exceptions) consisting of a main body, an arch and seven distinct protrusions (or processes). The space between the main body and the arch is called the spinal canal and is where the spinal cord runs through. 

The laminae are the two flat pieces of bone which join to form the back covering of the spinal canal. The spinous process extends from the lamina; they are the bumps felt when you run your hands down the back of your spine. These two sections are what is typically removed in a laminectomy.

Groups of vertebrae are divided into regions based on where along the spinal column they are found. 

• Cervical (in the neck)
• Thoracic (in your upper back attached to the ribcage)
• Lumbar (in the lower back waist area)
• Sacral (in the pelvis)

It is in the cervical or lumbar vertebrae that a laminectomy will likely take place.¹

Intervertebral discs

The intervertebral discs are flat layers that lie between each spinal bone – they act like cushions to absorb shock, provide flexibility and maintain the strength of the spine. If you have what's called a slipped disc, the inner gel-like substance leaks from its usual position in the spine, which can cause pressure.

Facet joints

These are the joints that help connect each vertebra, aligning your spine and allowing it to bend and rotate as a unit. They have a cartilage surface like the hip and knee joints and can be subject to arthritis leading to spinal stenosis and requiring the need for a laminectomy.

Spinal cord

The spinal cord is the bundle of nerve fibres enclosed within the spine. Its nerves run from the brain to the rest of the body to transfer information between them and conduct reflexes. Here’s an example of how this works: When you accidentally touch a hot stove, pain signals travel from your hands through the spinal cord to the brain to register as pain. The reflex to pull your hand away, in a concept known as the reflex arc, bypasses the brain to produce those movements. Though, to initiate the movements to run your hand under cold water, messages from the brain then travel down the spinal cord to your muscles. 

Indications for laminectomy

Spinal stenosis

The primary reason to undergo a laminectomy is when presenting with spinal stenosis, though the causes may differ. This most commonly affects the lumbar and cervical spine. In the lumbar spine, symptoms usually affect the back and/or one or both legs whereas in the cervical spine, symptoms typically involve the neck and arms.³

In the case of osteoarthritis, a form of degenerative stenosis, bony growths may form on some of the spinal joints, which can compress the nerves.⁶

Herniated disc

Over time the discs between our vertebrae may weaken (e.g. due to normal ageing or exercising and lifting heavy objects with improper posture and form) which can sometimes cause the inner gel-like substance to leak from its usual position and protrude. This is what is known as a slipped or herniated disc and the protruding portion may press on the spinal nerves.⁵ 

Typical symptoms of a herniated disc are a burning and stinging sensation that may radiate to the leg, though symptoms are not always present.

Tumours in the spinal canal

Various tumours that form on the spinal cord, may lead to spinal stenosis. Some tumours may originate in the spine, whereas others may come from cancer in another part of the body and grow to press on the spinal cord. This is known as metastatic spinal cord compression and must be treated promptly to not cause permanent nerve damage.

Cauda equina syndrome

This is an extreme form of spinal stenosis where all the nerves at the end of the spinal cord (the cauda equina) are severely compressed and can also be caused by a slipped disc or tumours as well as other conditions.⁷ The characterising symptoms of cauda equina syndrome are:

• Suddenly not feeling the need to pee or poop, or finding it hard to pee even when the bladder is full
• Urinary and/or faecal incontinence
• Pain that radiates from the lower back, down the buttocks to the calf on both sides
• Severe or worsening weakness or numbness in both legs
• ​​Saddle anaesthesia – which can involve numbness around your genitals and anus

This condition requires immediate medical attention (within 24 hours) to prevent the condition from progressing and leaving you with permanent paralysis or incontinence. In this case, though other treatments exist, an emergency laminectomy may be carried out. 

Traumatic injuries

Certain traumatic injuries may also require the need for a laminectomy, for example, due to swelling tissues around the spine or to ensure the complete removal of foreign objects.⁸

Procedure of laminectomy

Preparation

Once you have the date set for your laminectomy, try to be as healthy as you can through exercising, eating well and stopping smoking if you can as this can have a huge impact on the overall success of the surgery.

Pre-operative assessments

Before surgery, you will have a pre-operative assessment to ensure the operation goes as smoothly as possible. This appointment typically involves a general health check, blood tests and medical imaging of your spine; they assess your unique situation, making sure you are fit enough for the operation and allowing surgeons to prepare. You will also receive further information about how to best prepare for the surgery and you may want to discuss any concerns or questions you may have at the time.

Surgical process

Even on the day of the surgery, medical professionals will need to make sure that you know what the surgery entails and the potential risks so that you can consent for them to proceed.^9,10

During the procedure, you will be put to sleep under general anaesthesia so that you remain still and don't feel pain during the surgery. You will typically lie face down on a special mattress and it takes approximately one and three hours to complete.

Here are the major steps of the operation:

• A small incision(cut) is made down the middle of your back (or neck for a cervical laminectomy) over the affected area of your spine
• Muscle and other soft tissue over your spine is pulled away to expose the vertebrae
• The lamina, along with the spinous process is removed
• Muscles and soft tissue are realigned and any incisions are closed and stitched up

Depending on the source of spinal cord compression, a laminectomy may also be combined with another procedure to treat your condition better and maintain the function of the spine. These include:

• Trimming any protruding discs or bony growths on arthritic joints to further reduce the likelihood of nerve compression
• Spinal fusion – joining 2 or more vertebrae together to maintain the strength and stability of the spine

Risks and complications

Though the NHS does not consider a laminectomy to be a risky surgery, we still need to consider any risks and complications. These include:

Infection

This is one of the most common associated with this surgery, however it is usually successfully treated with antibiotics. 

Continuing symptoms

Though laminectomy is very effective at improving symptoms short term, symptoms may continue even after the operation or develop again later on. Factors such as another slipped disc, a weakened spine or post-operative scarring may cause symptoms to not improve or come back later on. 

Accidental tear of thin tissues surrounding the spinal nerves

This may cause the cerebrospinal fluid (the fluid that runs down the middle of your spine) to leak. If not resolved in the initial surgery, it will need another surgery to repair.

• Nerve damage and paralysis
• Blood clots 
• Bowel and bladder problems
• Spinal instability
• Bleeding

Recovery and rehabilitation

Immediately after the surgery, it is normal to experience some pain around the operation site, so painkillers will be given. However, the nerve compression symptoms should resolve immediately. Pain can last up to 6 weeks but should gradually reduce. 

To ensure optimal recovery, it is important to keep moving, even from the day after the surgery. This helps prevent blood clots and aids the recovery process. You will also be assigned a physiotherapist to help you regain strength and mobility and improve your recovery.

Though it can sometimes be hard, adhering to the programme suggested by your physiotherapist is vital to getting the best possible outcome from your laminectomy. Physiotherapy after the operation reduces the risk of scarring and other complications that may cause symptoms to resurface.

Summary

Compressed spinal nerves can be debilitating and have a huge impact on your daily life and without effective treatment, permanent damage and loss of function may occur. A laminectomy can be an excellent surgery to treat these conditions when non-surgical treatment has been ineffective. However, long-term improvement can be tricky as it heavily relies on how well the root cause can be fixed and how well you care for your spine afterwards.