What is spinal stenosis?

Spinal stenosis occurs when there is an abnormal narrowing of the spinal column. There are numerous possible causes, but essentially they lead to pressure on the spinal cord and/or the nerves that branch out from it.

Nerves

One or more fibres that transmit signals of sensation and motion between the brain or spinal cord and other parts of the body.

Spinal cord

A bundle of nerve tissue that runs from the brain through the spinal column and connects the brain to the body, transmitting sensory and motor signals.

Spinal column

The bony structure that comprises the individual vertebrae that enclose and protect the spinal cord and nerves located in the middle.

What is the spinal column?

The spinal column is made up of 24 articulated and 10 fused bones (vertebrae). The vertebrae are linked by discs that act as shock absorbers for the spine.

The spinal column plays a vital role in the support of the upper body. It allows us to keep an upright posture, bend and twist. It also protects the spinal cord.

Within the spinal column is the spinal canal. Spinal stenosis occurs when there is an abnormal narrowing of this canal. The spine can narrow at one or more of the following parts:

  • The space in the centre of the spine;
  • The canals where the nerves branch out from the spine, or;
  • The space between the vertebrae.

 

Nerves

One or more fibres that transmit signals of sensation and motion between the brain or spinal cord and other parts of the body.

Spinal cord

A bundle of nerve tissue that runs from the brain through the spinal column and connects the brain to the body, transmitting sensory and motor signals.

Spinal column

The bony structure that comprises the individual vertebrae that enclose and protect the spinal cord and nerves located in the middle.

Spinal canal

The cavity running through the middle of each vertabrae of the spine that contains the spinal cord.

Causes

Spinal stenosis can occur due to a variety of causes, including the following:

Acromegaly

A long-term disease characterised by excessive growth of the head, feet, hands and sometimes the chest, extremities and other structures, due to oversecretion of growth hormone from the pituitary gland.

Ankylosing spondylitis

A type of inflammatory arthritis that affects the joints of the spine, particularly where the spine attaches to the pelvis.

Congenital

Present from birth.

Disc

Intervertebral discs - layers of cartilaginous material that act as cushions between the vertebrae and the joints in the spine, enabling the spine to bend and twist.

Fractures

A complete or incomplete break in a bone.

Ligaments

Short, flexible fibrous tissue that connects the bones and cartilage of joints.

Herniation

Abnormal protrusion of tissue through an opening.

Spinal canal

The cavity running through the middle of each vertabrae of the spine that contains the spinal cord.

Paget's disease

A chronic condition that causes the abnormal enlargement and weakening of bones.

Types

The spine is made up of three regions - the cervical, thoracic and lumbosacral spine.

Lumbar stenosis is the most common, with around 75% of cases of stenosis occurring in this region. Lumbar stenosis commonly involves compression of the nerve roots of the lower back, leading to sciatica.

Cervical stenosis is less common, but is potentially more serious, as it can affect the muscles that help with breathing.

Thoracic stenosis is the least common type and can be associated with pain in the ribs.

Lumbar

Sometimes referred to as the lower spine, but is also the abdominal section of the torso, located between the diaphragm and pelvis.

Signs and symptoms

Some people with spinal stenosis may not experience any symptoms. For others, if the narrowing puts pressure on the nerves or spinal cord, there may be symptoms such as:

  • Numbness or weakness in the arms or legs;
  • Cramping and pain in the arms or legs;
  • Sciatica, or pain that radiates down the back of one leg;
  • Foot disorders, and;
  • Loss of bladder or bowel control.

Bladder

An organ in the lower abdomen that stores urine for excretion.

Nerves

One or more fibres that transmit signals of sensation and motion between the brain or spinal cord and other parts of the body.

Spinal cord

A bundle of nerve tissue that runs from the brain through the spinal column and connects the brain to the body, transmitting sensory and motor signals.

Bowel

The part of the digestive tract that comprises the small and large intestines.

Methods for diagnosis

Medical history

To help diagnose the cause of your symptoms, your doctor will take a detailed medical history, including your symptoms and past injuries, and ask questions about your overall health.

Physical examination

Your doctor will perform a physical examination to assess your strength, sensation and reflexes.

Imaging tests

X-rays

X-rays can be used to show any bone-related causes of spinal stenosis, such as osteoarthritis and bone spurs.

Computerised tomography (CT)

CT scans can provide detailed images of the spinal column to help better diagnose bone-related causes.

Magnetic resonance imaging (MRI)

MRI scans can be used to detect injury or disease of the soft tissue, such as disc herniation and tumours of the spine.

Bone scan

Bone scans can be useful in detecting fractures, infection or arthritis, but because they cannot differentiate between disorders, they are most commonly used alongside other imaging tests.

Bone scans

A nuclear scan used to detect abnormalities in the bone caused by cancer, arthritis, infection or injury.

Disc

Intervertebral discs - layers of cartilaginous material that act as cushions between the vertebrae and the joints in the spine, enabling the spine to bend and twist.

Fractures

A complete or incomplete break in a bone.

X-rays

A scan that uses ionising radiation beams to create an image of the body’s internal structures.

Spinal column

The bony structure that comprises the individual vertebrae that enclose and protect the spinal cord and nerves located in the middle.

Herniation

Abnormal protrusion of tissue through an opening.

Bone spurs

An abnormal growth extending from a bone such as a heel or knee.

Types of treatment

Non-surgical

Exercise

Exercise can be used to build up strength in the muscles of your arms and legs. Exercise can improve your balance, ability to walk, bend, move about and control pain.

Medications

Over-the-counter medications, such as paracetamol and ibuprofen, may provide relief from pain. Some people may be prescribed specific medication to ease muscular spasms.

Corticosteroid injection

Corticosteroids may be injected directly into the affected area around the spinal cord to provide temporary, or sometimes permanent, pain relief. These injections are not for regular use and are generally limited to only a few times each year.

Acupuncture

Acupuncture may prove effective in treating symptoms of mild to moderate cases of lumbar stenosis.

Surgery

When non-surgical treatment has not provided effective relief from symptoms, surgical treatment may be an option for some people. There are different procedures that can be used to alleviate the symptoms, including:

  • Decompression laminectomy - to remove the bony spurs in the spinal canal and free up space for the nerves and spinal cord, or;
  • Spinal fusion - in which additional bone is used to fuse two vertebrae together, which stops movement at the painful segment.

Surgical risks may include blood clots, infection, failure to provide relief and nerve injury.

Acupuncture

A form of complementary therapy that involves fine sterilised needles being inserted into the skin at specific points to treat medical conditions.

Lumbar

Sometimes referred to as the lower spine, but is also the abdominal section of the torso, located between the diaphragm and pelvis.

Nerves

One or more fibres that transmit signals of sensation and motion between the brain or spinal cord and other parts of the body.

Spinal cord

A bundle of nerve tissue that runs from the brain through the spinal column and connects the brain to the body, transmitting sensory and motor signals.

Clots

The thickened or solid mass formed from a liquid, such as blood. Blood clots normally form at an injury site to prevent further blood loss.

Spinal canal

The cavity running through the middle of each vertabrae of the spine that contains the spinal cord.

Potential complications

Severe cases of spinal stenosis may lead to chronic pain, paralysis, or faecal and urinary incontinence, which can be disruptive to normal life.

Paralysis

An inability to move or feel; a loss of muscle function or sensation.

Prognosis

For most people, there is good relief from symptoms without surgery. However, for others, non-surgical treatment may prove ineffective and surgery will be a good option.

Prevention

You may be able to lower the likelihood of spinal stenosis by:

  • Keeping your back healthy by engaging in regular exercise;
  • Maintaining a healthy weight;
  • Having good posture, and;
  • Not smoking.