Spondylolysis is a small crack between two vertebrae (the bones in your spine). Spondylolysis usually causes lower back pain. Most people don’t need surgery to treat it. Rest, medication and physical therapy are most successful when started early, so visit a healthcare provider if you or your child have back pain.
“Spondylolysis” is the medical term for a small crack (fracture) between two vertebrae in your spine. Your vertebrae are the 33 bones that make up your spinal column. A single bone in your spine is a vertebra — vertebrae is the plural form.
Healthcare providers sometimes refer to spondylolysis as pars defect or pars fractures because it affects your pars interarticularis — the tiny ridges of bone that link your vertebrae together.
Experts estimate that spondylolysis affects less than 10% of Americans each year. It’s more common in kids and teens, especially children who play contact sports.
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Lower back pain is the most common spondylosis symptom. The pain usually:
Some people with spondylolysis never experience symptoms. These people may only learn they have it when they have an imaging test for another reason later on.
Damage to part of your vertebrae called the pars interarticularis causes spondylolysis.
The pars interarticularis are thin pieces of bone that link your vertebrae directly above and below each other to form a working unit. These links let your spine move and flex. Anything that damages your pars interarticularis can crack them. Providers call these cracks pars fractures.
The most common causes of pars fractures include:
Anyone can experience spondylolysis. Certain groups of people have a higher risk of a pars fracture, including:
The back pain that comes with spondylolysis can also lead to reduced mobility (how well or comfortably you can move).
Untreated spondylolysis can lead to spondylolisthesis. Spondylolisthesis happens when your vertebrae are cracked or weakened enough by spondylolysis to slip out of place. If a slipped vertebra presses on a nerve, you may develop shooting pain in your legs (sciatica). Some people need surgery to relieve spondylolisthesis symptoms and get back to their normal routine.
A healthcare provider will diagnose spondylolysis with a physical exam and imaging tests. They’ll ask you about your symptoms and medical history. Tell your provider when you first noticed pain in your back and what you were doing right before you started feeling it.
Your provider will use imaging tests to take pictures of your vertebrae and the tissue around your spine, including:
Your provider will treat your pain and other symptoms to give the pars fracture time to heal. Depending on which vertebrae are affected and how severe the cracks are, you might need treatment anywhere from a few weeks up to a few months.
The most common spondylolysis treatments include:
It’s rare to need surgery for spondylolysis. Most of the time, people feel better with nonsurgical treatments.
Some people need surgery to stabilize their spine. During a pars repair surgery, your surgeon can usually fix a pars fracture without needing to perform a spinal fusion (fusing two vertebrae together to form one bone). If you need surgery, your provider or surgeon will tell you what to expect and how long it will take to recover.
Pars fractures can take up to six months to heal. Most people with spondylolysis begin feeling better as soon as they start treatment. Follow your treatment plan for as long as your provider or physical therapist suggests, even if your symptoms start to get better sooner. It’s important to give your spine all the time it needs to heal completely.
Ask your provider when you can start playing sports or doing intense physical activity again.
You can’t usually prevent spondylolysis. Follow these general safety tips to reduce your risk of a pars fracture:
If you have spondylolysis, nonsurgical treatments like rest, medication and physical therapy should improve your symptoms. These treatments can’t undo the fracture, but they can help you return to your daily activities without pain as soon as possible.
Talk to your provider before resuming intense physical activity. Even if your pain and other symptoms have improved, your vertebrae need time to heal.
Your provider will monitor your treatment progress. As you start to have less pain and more flexibility, you’ll be able to return to your regular activities gradually. People recovering from spondylolysis usually need at least a few weeks (and up to a few months) of treatment before they can resume intense physical activities like playing sports and working out.
The sooner you see a healthcare provider, the faster they can diagnose and treat spondylolysis. Visit a healthcare provider as soon as you notice low back pain that lasts more than a few days or is severe enough that it makes it hard or impossible to participate in your usual routine.
Go to the emergency room if you experience a trauma like a fall or car accident. Go to the ER if you lose feeling or can’t move a part of your body.
Spondylolysis and spondylolisthesis are related conditions that affect your spine.
Spondylolysis and spondylosis have similar sounding names and are both conditions that affect your spine. They both also cause symptoms like pain and stiffness.
Spondylolysis is a specific injury — having a pars fracture in the pars-interarticularis in your spine.
Spondylosis is a general term that applies to any age-related breakdown (degeneration) in your spine.
Pars fractures involved in spondylolysis usually heal over time. But a healthcare provider should still diagnose and treat them. Visit a provider if you’re experiencing lower back pain that lasts more than a few days or is severe enough to affect your daily routine. They’ll suggest treatments that will make sure your vertebrae heal safely and as fast as possible.
A note from Cleveland Clinic
Spondylolysis is caused by tiny cracks where the bones in your spine link together. It usually causes pain in your lower back. Most people with spondylolysis are able to return to sports and activities as soon as their vertebrae heal and their pain goes away.
Don’t ignore lower back pain — especially if it lasts more than a few days or prevents you from doing your usual activities. A healthcare provider will diagnose the cause of your pain and recommend treatments that protect your spine and help it heal.
Last reviewed by a Cleveland Clinic medical professional on 03/09/2023.
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