What is spondylolisthesis?
Spondylolisthesis literally means 'slipped vertebra.' Forward slippage (anterolisthesis) is far more common than backward slippage (retrolisthesis). The slip itself is graded I through V based on how far the upper vertebra has shifted relative to the one below. Many cases are mild, asymptomatic, and discovered incidentally on imaging, and generally not a serious or dangerous condition unless nerve compression or significant instability develops.
Anatomy
Spondylolisthesis is closely related to (and often confused with) spondylolysis, which is a stress fracture of a small piece of bone called the pars interarticularis. A pars defect can predispose the vertebra above to slip forward; that is isthmic spondylolisthesis. In older adults, slippage occurs from progressive arthritis of the facet joints; that is degenerative spondylolisthesis, the most common adult form.
Types
Degenerative
Most common in adults over 50. Caused by arthritic facet joint changes; most often at L4–L5.
Isthmic
Caused by a stress fracture of the pars interarticularis. Often discovered in adolescents or young adults.
Congenital
Abnormal vertebral development present from birth.
Traumatic
Resulting from a high-energy injury.
What are the symptoms of spondylolisthesis?
- Lower back pain, often worse with activity
- Leg pain or numbness (sciatica-like symptoms) when nerves are compressed
- Tight hamstrings or a stiff gait
- Pain relieved by rest or leaning forward
- Sensation of the back giving way
What causes spondylolisthesis?
- Degenerative arthritis of the facet joints (most common in adults)
- Pars stress fracture (isthmic)
- Congenital vertebral developmental abnormalities
- Traumatic injury
Who is at risk?
- Age over 50 for degenerative type
- Female sex (degenerative spondylolisthesis is more common in women)
- Sports involving repetitive lumbar extension (gymnastics, football linemen, weightlifting) for isthmic type
- Family history
How is spondylolisthesis diagnosed?
Diagnosis is confirmed on standing and flexion-extension X-rays, which show the slip itself and whether it changes with motion (a marker of instability). MRI characterizes nerve compression and disc health. CT is helpful for evaluating a pars defect.
When to see a spine surgeon
Evaluation is recommended for persistent back or leg pain, progressive weakness, or imaging showing significant slippage with neurologic symptoms. Most low-grade cases are managed without surgery.
How is spondylolisthesis treated without surgery?
Conservative care includes physical therapy with a focus on core stabilization, activity modification, bracing in select cases, and image-guided injections. The majority of patients with mild slippage are managed effectively without surgery.
When is surgery needed?
Spondylolisthesis is the one condition where the right surgical answer truly depends on the specific pattern. For low-grade, stable slips driven primarily by nerve compression, an endoscopic decompression alone can give excellent relief without ever fusing the segment. For slips that are clearly unstable, stabilization is the right answer, and in those cases I rely on minimally invasive techniques, including endoscopic TLIF, to keep recovery as fast and comfortable as possible. The goal is always the least invasive option that durably solves the problem.
Common questions
Is spondylolisthesis serious?
Usually not. Many cases are mild, asymptomatic, and discovered incidentally on imaging. It becomes a concern when the slip compresses nerves or the segment is genuinely unstable, which is when treatment decisions matter most.
Can spondylolisthesis be treated without surgery?
Yes. The majority of patients with mild slippage do well with core-stabilization physical therapy, activity modification, bracing in select cases, and image-guided injections.
Does spondylolisthesis always require a fusion?
No. For low-grade, stable slips driven primarily by nerve compression, an endoscopic decompression alone can give excellent relief without fusing the segment. When a slip is clearly unstable, stabilization is the right answer, performed with minimally invasive techniques including endoscopic TLIF.
How is spondylolisthesis diagnosed?
Standing and flexion-extension X-rays confirm the slip and show whether it moves with position, which is the marker of instability. MRI characterizes nerve compression, and CT helps evaluate a pars defect.
Related procedures
Endoscopic TLIF
A next-generation lumbar fusion that combines the structural goals of a traditional TLIF with the tissue-sparing advantages of endoscopic surgery.
Lumbar Fusion (PLIF / TLIF)
Permanently joins two or more vertebrae in the lower back to eliminate painful motion and restore spinal stability.
Anterior Lumbar Interbody Fusion (ALIF)
A two-stage spinal surgery that combines an anterior approach through a small abdominal incision with robotic-guided posterior pedicle screw fixation.
Lateral Lumbar Interbody Fusion (LLIF / XLIF / DLIF)
A minimally invasive spine surgery that reaches the damaged disc through a small incision on the side rather than through the back.
Related conditions
Endoscopic treatment options
Many patients with spondylolisthesis can be treated through incisions of about 7 to 10 mm using endoscopic spine surgery. Dr. Kazarian performs the two-portal endoscopic technique, and explains how it compares with uniportal endoscopy. Whether an endoscopic approach fits your case depends on your imaging and symptoms; see the candidacy guide.
This page is for general educational purposes and is not medical advice. Diagnosis and treatment recommendations require an in-person evaluation. To schedule a consultation with Erick R. Kazarian, MD, please book an appointment.