Spondylolisthesis

Spondylolisthesis is a condition in which one vertebra slips forward relative to the vertebra below it, which can compress nerves, destabilize the spine, and produce low back pain or symptoms that travel into the legs.

What spondylolisthesis involves and how it affects your spine

Spondylolisthesis most often occurs in the lower lumbar spine, typically at the L4-L5 or L5-S1 levels, where the spine bears the greatest mechanical load. The forward slip can be caused by a stress fracture in a small connecting piece of bone in the vertebra's arch — the pars interarticularis — a form called spondylolytic or isthmic spondylolisthesis — or by degenerative changes in the disc and facet joints that no longer hold the vertebra in place, which is called degenerative spondylolisthesis and is more common in adults over 50.

The degree of slip ranges from mild — barely visible on imaging — to severe, and is measured in grades from I to IV. Many people with low-grade spondylolisthesis have minimal or no symptoms; others experience chronic lower back pain, stiffness, and symptoms that travel into the buttock or legs from nerve involvement.

Why spondylolisthesis is often mismanaged

People with spondylolisthesis are sometimes told to avoid activity broadly or advised toward surgery before conservative rehabilitation has been fully explored. Low to moderate-grade spondylolisthesis in most adults responds well to targeted physical therapy that stabilizes the spine, strengthens the surrounding musculature, and reduces nerve-related symptoms.

Why the grade on imaging doesn't predict how much pain you'll have

A grade I or II slip can produce significant symptoms in one person and none in another. What matters clinically is how well the surrounding muscles are supporting the unstable segment and whether nerve structures are being compressed. A physical therapist can assess functional stability and design a program that addresses the specific demands of your spine.

How Sword Health can help

A physical therapist can assess spondylolisthesis in the context of your movement, identify what's contributing to your symptoms, and guide you through a stabilization-focused rehabilitation program. Sword makes that level of specialized care available from home, with clinical oversight at every stage.