Spinal Stenosis, Sciatica and Lower Back Pain

According to the Evening Standard, Queen Elizabeth II was a long term sufferer of sciatica. The Palace said that 'the Queen's chronic back problem was 'a private medical matter', but it is understood that she suffered from sciatica since a 2003 operation on damaged cartilage within a knee' (3). 

As the Standard noted, sciatica within the elderly is often caused from osteoarthritis within the spine which may cause limited walking distance and cause one's leg to seize after having walked 30 to 40 yards (3). 

But, what if sciatica is caused via spinal stenosis? What is the difference between stenosis and osteoarthritis? How can one tell the difference between the two? 

Osteoarthritis is the most common form of arthritis and occurs when cartilage breaks down to create a lack of cushioning between joint surfaces. This may force bones to rub together and can cause pain, stiffness, and swelling. As osteoarthritis symptoms worsen, spinal stenosis can develop.

Spinal stenosis is a condition that can cause narrowing of the neural canal and foramina which can result to the compression of the nerve roots and lead to symptoms such as pain, weakness, and numbness (5). The upper neck (cervical) and lower back (lumbar) areas are most frequently affected, although the thoracic spine also can be compressed most frequently by a disc herniation (5).  The condition can cause symptoms such as pain, numbness, and weakness (5). 

Three different anatomical sites within the vertebral canal can be affected by spinal stenosis (5):

1. The central canal, which houses the spinal cord, can be narrowed and lead to compression of neural elements and reduction of blood supply to the spinal cord in the cervical area of the neck and the cauda equina in the lumbar area. 
2. Secondly, the neural foramen, which are openings through which the nerve roots exit the spinal cord, can be compressed as a result of disk herniation, hypertrophy of the facet joints and ligaments, or unstable slippage of one vertebral body relative to the level below. 
3. Lastly, the lateral recess, which is seen in the lumbar spine only and is defined as the area long the pedicle that a nerve root enters just before its exit through the neural foramen, can be compressed from a facet joint hypertrophy. Depending on the level of the spine affected, each type of compression can lead to different symptoms that warrant a particular treatment modality.
   

Most patients will experience some type of pain associated with the spine but luckily, even without surgery, the majority will have an uneventful recovery (6). Only 1 to 3% will have a herniated disc and less than 2% will have compression of a nerve root (6).

Spinal stenosis is common with ageing but predicting which individual will develop symptoms is not possible. In most cases, the degenerative process can be controlled by changes in lifestyle (6).

LSS is a significant cause of disability in older individuals and a common indicator for spinal surgery in patients older than 65 years. Typical, symptoms of lumbar spinal stenosis include (6):

• Pain at the gluteal muscles and/or lower extremities which may or may not be associated with the lower back.
• Neurogenic claudication is a 'hallmark' symptom and characterised by pain in the lower limbs and the presence of neurological symptoms exacerbated by walking.
• In addition, these symptoms are exacerbated by standing and lumbar extension.

Anterior flexion of the trunk and maintaining a sitting and supine position tends to alleviate symptoms.

Central stenosis arises from anterior ligamentum flavum hypertrophy compounded by posterior disk bulging (4). This condition is more prevalent at the L4 to L5 level than other spinal segments. Meanwhile, lateral recess stenosis can results from facet osteoarthritis (arthropathy) and osteophyte formation that can compress the nerve before it passes the intervertebral foramen. 

Foraminal stenosis can result from: 

• Disc height loss.
• Foraminal disc protrusion.
• Osteophyte formation.

With such changes, impingement on the nerve root inside the intervertebral foramen can be caused. Extraforaminal stenosis is usually due to lateral disc herniation which causes compression on the nerve root after exiting the intervertebral foramen laterally (6).

Physical therapy tends to be recommended for patients with mild to moderate LSS (4). Patients with severe LSS typically undergo a trial of conservative treatment before surgery is proposed (4). 

Most literature supports the notion that exercise therapy should be considered before surgery. Surgery leads to better longer-term (2 years) outcomes for pain and disability (4).  

1. Ciardi, G., Lamberti, G., Casati, V., Paris, E. (2023) Rehabilitation Outcome Measures in Patients with Spinal Stenosis: A Literary Review, Phsysiologia, MDPI; 3: 421-432. 

2. Clark, A., Lucke-Wold, B. P. (2022) Acupuncture and Spinal Stenosis: Considerations for Treatment, HHS Public Access, 1; 1: 23-31. 

3. Evening Standard, The Queen is in great pain but insists she will open Parliament, https://www.standard.co.uk/hp/front/the-queen-is-in-great-pain-but-insists-she-will-open-parliament-... [Online]. 

4.Macedo, L. G., Hum, A., Kuleba, L., Mo, J., Truong, L., Yeung, M., Battie, M. C. (2016) Physical Therapy Interventions for Degenerative Lumbar Spinal Stenosis: A Systematic Review, 93; 12: 1646-1660. 

5. Raja, A., Hoang, S., Patel, P., Mesfin, F. B. (2023) Spinal Stenosis,  StatPearls Publishing LLC, https://www.ncbi.nlm.nih.gov/books/NBK441989/#:~:text=Most%20patients%20will%20experience%20some,com.... [Online]. 

6. Wu, L., Munakomi, S., Cruz, R. (2024) Lumbar Spinal Stenosis, https://www.ncbi.nlm.nih.gov/books/NBK531493/ [Online].