Deciding on Surgery for Isthmic Spondylolisthesis

For some people with isthmic spondylolisthesis, the symptoms of pain that radiate down the leg and/or lower back pain can be severe and can adversely impact their ability to participate in everyday activities and simply function well enough to get through the day.

Research has shown that patients with a spondylolisthesis of greater than a 50% slippage, termed a grade 3 spondylolisthesis (50 to 75% slippage), or a grade 4 spondylolisthesis (greater than 75% slippage), generally do not respond to non-surgical treatment and are likely candidates for surgery.1

Slippage that is less severe (less than 50%) is far more common. Lesser slips can be equally painful, however, if associated with significant disc degenerative changes and nerve compression.

When to Consider Fusion for Spondylolisthesis

For patients with a grade 3 or grade 4 spondylolisthesis, as well as for patients with severe pain and inability to function, who have not gotten better after at least 3 to 6 months of nonsurgical treatment, a spinal fusion surgery may be a reasonable option.

Some patients may require immediate medical attention if they experience neurological problems, such as progressive leg numbness or weakness, and/or bowel or bladder dysfunction or incontinence . These situations are rare, however, and the vast majority of time the decision whether or not to have a spinal fusion for isthmic spondylolisthesis symptoms is entirely up to the patient.


Surgical Considerations for Spondylolisthesis

When deciding whether or not to have a spine fusion surgery to treat severe symptoms from spondylolisthesis, there are multiple considerations, including:

  • As a general rule, surgery should not be considered until a concerted effort of 6 to 12 months of non-surgical treatments has been made. The most common treatments include physical therapy, injections, manual manipulations, anti-inflammatory medications, and oral steroids.
  • Surgery may be considered sooner if the patient's spondylolisthesis is getting worse (i.e. the slip is progressing).
  • Surgery may be recommended sooner if the patient experiences pain that is so severe that it inhibits his or her ability to sleep, walk, and/or function in daily activities.
  • Patients who smoke or who have excessive weight may not be ideal candidates for surgery. Some surgeons will require the patient to stop smoking (meaning stop any intake of nicotine) and/or to lose weight prior to surgery in order to improve the probability for the patient to have a safe and successful surgery.
  • There are multiple surgical approaches to consider, including minimally invasive vs open techniques and posterior only vs combined anterior/posterior fusion procedures. Even larger anterior/posterior spinal fusion procedures can often be performed as a single surgery with a short hospital stay. Although surgeon preference may vary, the goals of the spinal fusion surgery are the same: relieve pressure on pinched nerves and obtain spine stability (immediately with spinal implants and permanently with bone fusion).
  • In some cases, repair of the bone defect may be considered without fusion of the motion segment if there is no nerve compression or significant disc degenerative changes.

Read more Spinal Fusion Surgery for Isthmic Spondylolisthesis


Surgeon Skill and Experience

As with most types of spine surgery, the results of surgery for spondylolisthesis are to a certain extent dependent on the skill and experience of the individual spine surgeon.

Patients are well advised to ask questions of their spine surgeon such as:

  • How many isthmic spondylolisthesis surgeries does the surgeon do? As a general rule, more is better, meaning that a surgeon who does 40 fusions to treat isthmic spondylolisthesis each year will likely have better results than a surgeon who only does 2 or 3 of this type of fusion surgery.
  • How long is the typical recovery time after this type of surgery? In general, if the surgeon's patients tend to go home within a day of the surgery, it is better than if most of the surgeon's patients need to recover in the hospital for 3 or 4 days.

Learn more about Guidelines for Evaluating a Spine Surgeon.

At the time of this article, studies have shown that when the indications are met, outcomes from fusion surgery for isthmic spondylolisthesis are generally very good (>85% good-excellent results, >90% fusion rates), with minimal chance for symptomatic adjacent level problems (<4%).2-5


  • 1.Seitsalo S, Osterman K, Hyvarinen H et al. "Severe spondylolisthesis in children and adolescants. A long-term review of fusion in situ.," Journal of Bone and Joint Surgery (British Volume) 72-B, Issue 2 (1990): 259-265.
  • 2.Swan J, Hurwitz E, Malek F, van den Haak E, Cheng I, Alamin T, Carragee E. "Surgical treatment for unstable low-grade isthmic spondylolisthesis in adults: a prospective controlled study of posterior instrumented fusion compared with combined anterior-posterior fusion," Spine Journal 2006 Nov-Dec (6): 606-14
  • 3.Bae JS, Lee SH, Kim JS, Jung B, Choi G. "Adjacent segment degeneration after lumbar interbody fusion with percutaneous pedicle screw fixation for adult low-grade isthmic spondylolisthesis: minimum 3 years of follow-up," Neurosurgery 2010 Dec;67(6):1600-7.
  • 4.Kim JS, Choi WG, Lee SH. "Minimally invasive anterior lumbar interbody fusion followed by percutaneous pedicle screw fixation for isthmic spondylolisthesis: minimum 5-year follow-up," Spine Journal 2010 May;10(5):404-9.
  • 5.Kim JS, Kang BU, Lee SH, Jung B, Choi YG, Jeon SH, Lee HY. "Mini-transforaminal lumbar interbody fusion versus anterior lumbar interbody fusion augmented by percutaneous pedicle screw fixation: a comparison of surgical outcomes in adult low-grade isthmic spondylolisthesis," Journal of Spinal Disorders and Technique 2009 Apr;22(2):114-21.