What is a Spinal Decompression?
The “spinal decompression” is one of the most common procedures done in spine surgery, with over 600,000 performed in the U.S. per year (1). The goal of this post is to understand their utility, purpose, types and the risks.
In general, the term spinal decompression refers to removing any tissue which is compressing a nerve in or around the spinal canal. The spinal column is composed of discs and vertebrae that are connected by ligaments and muscle. Inside the spinal column is the spinal canal where the nerves and spinal cord reside. There are several types of tissues which can compress nerves in the spinal canal, including common sources such as herniated discs, bone spurs from arthritis, or thickening of the ligaments surrounding the spine. Other causes such as tumor and infection which can also cause compression are less common.
The most common need for a spinal decompression however is degenerative stenosis which has a very high prevalence in the US population at 11% or over 100 million people (2). Stenosis is a term which comes from the Greek stenos, which means narrowing. Stenosis occurs when bone spurs and thickened worn out ligaments around the spine enlarge crowding the nerves and spinal cord. Stenosis can also occur with disc degeneration that can either cause a collapse of the spinal canal, or protrusions into the spinal canal that narrow the space. When the spinal nerves and cord become damaged it causes pain numbness, and weakness. Stenosis can be functionally limiting, and depending on its location make activities of daily living painful, and difficult.
Stenosis can occur anywhere in the spinal column however, the lumbar spine or low back is the most common location. Lumbar stenosis results in back pain, difficulty walking, numbness and weakness of the legs (3). The diagnosis of stenosis is confirmed by a physical examination performed by your doctor and some type of advanced spine imaging such as magnetic resonance imaging (MRI) or computer tomography (CT). However, just because you have stenosis on your MRI scan does not mean you need treatment. Although stenosis is typically progressive, you should only be treated if you are symptomatic.
Stenosis can unfortunately not be definitively treated by over the counter non-steroidal anti-inflammatory drugs (NSAIDs) or physical therapy, which only offer temporary relief from pain (4). Other medical treatments such as gabapentin, opioids, and serotonin reuptake inhibitors have been poorly studied in the treatment of lumbar stenosis. These medications may provide temporary relief from pain, but also do not offer long term solutions to lumbar stenosis. Even epidural steroid injections—injections which are performed directly into the spine— offer very limited benefit for the treatment of lumbar stenosis (5). Relief from injections can be expected to last for 6 weeks and may be reasonable for short term relief (such as if you need to attend a wedding). The reason these treatments are ineffective, is because they do nothing to change the mechanical compression of nerves ongoing in the back. The North American Spine Society (NASS) does not recommend physical therapy, NSAIDS or epidural steroid injections for the long term treatment of stenosis (2).
If non-invasive treatments don’t work for stenosis, what does? The answer is the spinal decompression procedure. Decompression surgeries are typically performed through a procedure called a laminectomy and partial facetectomy. The term laminectomy is a combination of words Lamina and -ectomy which is Greek for removal. The lamina is the part of the bone which covers the back of the spinal canal. Removing part or all of the lamina gives the surgeon access to the spinal canal to decompress the nerves. The lamina can be totally removed without ill effects. The facets are small paired joints on either side of the spine from which bone spurs can grow. The process of removing these bone spurs is known as a partial facetectomy, but in generally only a small portion is removed because total removal of a facet will result in instability.
Just because you have spinal stenosis on MRI does not mean you need to rush into surgery. Surgery is generally only performed for 1 in 10 patients with symptomatic spinal stenosis and in fact many patient’s symptoms remain stable for years before they get worse (6). Nonetheless, surgical decompression is the standard treatment for spinal stenosis with symptoms that are progressive or not tolerable. Randomized controlled studies comparing non-operative treatment (exercise, PT and medication) to decompressive surgery have shown that surgery offers better improvement in pain and functional disability over the long term (3,7). The North American spine society, as well as several other spine authorities recommends surgical decompression for spinal stenosis (2).
What are the types of spinal decompression procedures?
So lets now talk more in-depth about the spinal decompression procedure and the ways in which it can be performed. There are several styles of spinal decompression procedure. A direct spinal decompression is done when the surgeon actually opens the spinal canal and removes tissue.
Types of direct spinal decompressions include the dome laminectomy where the bottom portion of the lamina is shaved off, leaving most of the lamina intact. A hemilaminectomy is another direct spinal decompression and means only a small opening is produced on one side of the lamina. A complete laminectomy means the entire lamina is removed. Nowadays, a laminectomy can be performed from the inside of the spinal canal thus limiting tissue trauma. What this means is that a complete laminectomy may be unnecessary, a small opening (hemilaminectomy) can be made on one side of the spinal canal to get access and the canal can be cleaned from the inside with minimal tissue resection.
When your spine can also become kinked or crushed down because of degeneration, a procedure called the spinal fusion can be performed to realign the broken down segment. When a spinal fusion is used to realign the spine, an “indirect decompression” is performed, because the nerves were compressed simply because the vertebrae were not in alignment. A direct Spinal decompression can also be performed along with a spinal fusion procedure. To learn more about spinal fusion please also see my blog post on spinal fusion.
What are Some problems with Spinal Decompression?
By far the most common complication with spinal decompression is a spinal fluid leak. The nerves in the spine are contained in a sausage like lining called the dura that can become thinned—almost like a thin sheet of tissue paper-- in cases of severe stenosis making it vulnerable to rupture. If a spinal fluid leak occurs, it can usually easily be repaired and most people will not notice any ill effects. Spinal fluid leaks are very common occurring in about 10% of cases (3).
In a laminectomy you are also not stopping motion of the spine (unlike a spinal fusion), arthritic joints can continue to be inflamed and produce tons of joint fluid that can cause cyst formation. Stenosis can reoccur from these cysts or from continued wear of the spine. If stenosis reoccurs, it again must be removed and sometimes it requires a fusion (joining the vertebrae together with rods and screws). Recurrent stenosis tends to occur at a rate of around 4% for surgically treated stenosis patients (3).
In general, some portion of bone must be removed to perform spinal decompression. If too much bone is removed this can result in destabilization of the spine which is a painful condition. When the spine is destabilized, the vertebrae are no longer linked to one another. Think of it as a broken link in a chain that hinges open every time its pulled. Spinal instability is painful, can cause stenosis to reoccur and typically requires a surgical fusion to treat. This complication is thankfully very rare.
Who should have a spinal decompression?
Anyone who has symptomatic spinal stenosis (back pain, leg pain, numbness, weakness or difficulty walking) that has been confirmed by a surgeon is a possible candidate for spinal decompression. Although non-operative treatments are typically not helpful for spinal stenosis, they should still be attempted for at least 6 weeks to see if time makes the symptoms better. If you try an epidural steroid injection and the pain gets better temporarily, this is also a great sign that surgery is right for you, as you can expect similar relief albeit on a more permanent basis.
Talk with your surgeon and see if spinal decompression is the right choice for you.
References:
1. Agency for Healthcare Research and Quality. Overview of the National Inpatient Sample, (NIS). Health care cost and utilization project (H-CUP) [Internet]. [cited 2025 Feb 13]. Available from: https://hcup-us.ahrq.gov/nisoverview.jsp
2. Katz JN, Zimmerman ZE, Mass H, Makhni MC. Diagnosis and Management of Lumbar Spinal Stenosis: A Review. JAMA. 2022 May 3;327(17):1688.
3. Weinstein JN, Tosteson TD, Lurie JD, Tosteson ANA, Blood E, Hanscom B, et al. Surgical versus nonsurgical therapy for lumbar spinal stenosis. N Engl J Med. 2008 Feb 21;358(8):794–810.
4. Cashin AG, Wand BM, O’Connell NE, Lee H, Rizzo RR, Bagg MK, et al. Pharmacological treatments for low back pain in adults: an overview of Cochrane Reviews. Cochrane Database Syst Rev. 2023 Apr 4;4(4):CD013815.
5. Friedly JL, Comstock BA, Turner JA, Heagerty PJ, Deyo RA, Bauer Z, et al. Long-Term Effects of Repeated Injections of Local Anesthetic With or Without Corticosteroid for Lumbar Spinal Stenosis: A Randomized Trial. Arch Phys Med Rehabil. 2017 Aug;98(8):1499-1507.e2.
6. Wessberg P, Frennered K. Central lumbar spinal stenosis: natural history of non-surgical patients. Eur Spine J. 2017 Oct;26(10):2536–42.
7. Malmivaara A, Slätis P, Heliövaara M, Sainio P, Kinnunen H, Kankare J, et al. Surgical or Nonoperative Treatment for Lumbar Spinal Stenosis?: A Randomized Controlled Trial. Spine. 2007 Jan;32(1):1–8.