SpineUniverse Case Study Library

Lumbar Spinal Stenosis with Spondylolisthesis

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Patient History

A 59-year-old female presented with history of chronic bilateral lower extremity radicular pain. The patient reported difficulty walking and inability to exercise due to severe thigh and calf pain after about 5 minutes of exertion. She described the pain as 10 out of 10 and her pain was relieved upon bending forward.

The patient has been diagnosed in the past with lumbar spinal stenosis at L3-L4 and L4-L5 with spondylolisthesis grade 1 at L4-L5.


The patient was an overweight female with a depressed affect. She had:

  • A bilateral positive straight-leg raise and a positive reverse straight-leg raise in prone position
  • 5/5 muscle strength in all major muscles groups in her bilateral lower extremities
  • Bilateral decreased patellar and Achilles reflexes
  • Slight sensory dysthesia in the L5 dermatomal distribution but otherwise intact light touch sensation T2-S2
  • Decreased range of motion slightly secondary to leg pain
  • Able to heel walk and toe walk in the office
  • Full range of motion in the lower extremities

Prior Treatment

Non-operative care for lumbar spinal stenosis during the last 2.5 years included epidural injections that provided limited pain relief.

Pre-treatment Images

pre-operative lumbar saggital MRIFigure 1. Pre-operative sagittal MRI

lumbar axial MRI studies: left is L3-L4; right is L4-L5Figure 2. Axial MRI (Left: L3-L4) (Right: L4-L5)

X-ray: Flexion and extension films of the lumbar spine show a stable spondylolisthesis at L4-L5


  • Lumbar spinal stenosis, L3-L4, L4-L5
  • Spondylolisthesis grade 1, L4-L5

Suggest Treatment

Indicate how you would treat this patient by completing the following brief survey. Your response will be added to our survey results below.

Selected a treatment

The patient underwent an implantation of two 12mm X-STOP® interspinous spacers at L3-L4 and L4-L5 under local anesthesia. There were no intra-operative or post-operative complications.

During the procedure the facet joints were trimmed to allow for optimal placement of the device. The overall blood loss was around 60cc. The patient was stable throughout her hospital stay and was discharged within 24 hours of the operation.

Post-treatment Images

Operative-day radiographs (Figs. 3A, 3B)

operative-day lumbar anteroposterior x-ray, X-STOP Figure 3A. Anteroposterior

operative-day lumbar lateral x-ray, X-STOPFigure 3B. Lateral

Post-operative x-rays at 2 months (Figs. 4A, 4B)

2 months post-operative, lumbar anteroposterior x-ray; X-STOPFigure 4A. Anteroposterior

2 months post-operative, lumbar lateral x-ray; X-STOPFigure 4B. Lateral

Medtronic Technology Featured
X-STOP® Interspinous Process Decompression (IPD®) System


Pre-operatively, the patient reported severe pain (10 out of 10). A week after the operation, the patient reported that she was able to walk, and that her pre-operative symptoms (bilateral lower extremities numbness and cramping) had been resolved. She did report some residual pain in the L5 distribution on the right side, but overall was very happy with her post-operative course. At the 2 year follow-up the patient remained symptom-free other than the residual pain in the L5 distribution on the right side.

Pain relief following X-STOP® spacer implantation remained stable in this patient during the intermediate term (2 years).

Results for This Patient

Zurich Claudication Questionnaire (ZCQ)
    Pre-op      1 Year Post-op
2 Years Post-op
Symptom Severity
(Scale of 1 to 5;
1 being no symptoms)
4.9 1.6 1.6
Physical Function
(Scale 1 to 4;
1 being functioning comfortably)
3.2 1 1
Patient Satisfaction
(Scale 1 to 4; 1 being very satisfied)
- 1.8 1


Indications for Use: The X-STOP® Interspinous Process Decompression (IPD®) System is indicated for treatment of patients aged 50 or older suffering from neurogenic intermittent claudication secondary to a confirmed diagnosis of lumbar spinal stenosis (with X-Ray, MRI and/or CT evidence of thickened ligamentum flavum, narrowed lateral recess and/or central canal narrowing). The X-STOP® device is indicated for those patients with moderately impaired physical function who experience relief in flexion from their symptoms of leg/buttock/groin pain, with or without back pain, and have undergone a regimen of at least 6 months of non-operative treatment. The X-STOP® device may be implanted at one or two lumbar levels in patients in whom operative treatment is indicated at no more than two levels.

Note to patients: This treatment is prescribed by your doctor. It is not for everyone. Please talk with your doctor and see if it is right for you. Your doctor should discuss all potential benefits and risks with you. Although many patients benefit from the use of this treatment, approximately half of the patients who received the X-STOP® device in the 2-year study experienced a degree of pain relief and ability to increase their activity levels that was sufficient to be considered a successful outcome at 2 years after surgery. This compares with the control group treated with non-surgical care that had a 6% successful outcome treatment success rate. (X STOP® IPD® System Summary of Safety and Effectiveness, 2005.)

As you read this, please keep in mind that all treatment and outcome results are specific to the individual patient. Results may vary. Complications, such as improper implant positioning, dislodgement or failure, fracture of the spinous process, or the need for additional surgery are some of the potential adverse risks. Medication or additional surgery may be necessary to correct some of these potential adverse events. Please consult with your physician for a complete list of indications, warnings, precautions, adverse events, clinical results, and other important medical information. Also refer to the Important Safety Information at www.xstop.com [http://xstopspacer.com/important.aspx].

A prescription is required. For further information, please call Medtronic at (800) 876-3133. Dr. Shamie is a consultant for Medtronic, but has not been compensated for this case study.

Case Discussion

The case above presents an appropriately selected patient with painful neurogenic claudication due to two-level lumbar spinal stenosis, who had a favorable outcome following implantation of two X-STOP® interspinous spacer devices. In general, the implantation of this relatively new device is indicated as a less invasive alternative to more extensive decompressive laminectomy and fusion surgery in selected patients with documented one or two-level spinal stenosis.

It is important to demonstrate pre-operatively in patients for whom the X-STOP® device implant is proposed that their painful neurogenic claudication symptoms are precipitated by standing and walking, but relieved by sitting, or assuming a forward flexion posture. Properly inserted, the X-STOP® implant device slightly distracts the vertebral segment. It works to bring about a slight enlargement of the neural foramina and central spinal canal at the insertion level and is similar to what occurs naturally when the patient with spinal stenosis assumes forward flexion posture. Therefore, screening patients who may be appropriate for this procedure requires careful pre-operative history, physical examination, and x-ray films.

The device is relatively contraindicated in patients with severe osteoporosis that is documented to be greater than two standard deviations from the norm on bone densitometry, since fracture of the posterior spinous process/es may occur during surgery. For this reason, the surgeon may discuss and request consent for traditional laminectomy and/or fusion if inadvertent spinous fracture occurs during device implantation.

That being said, it is very gratifying to learn about successful outcomes using the X-STOP® implant device for lumbar spinal stenosis. Lumbar spinal stenosis can be a disabling condition and it appears to be on the rise in our aging and overweight populations.

Author's Response

I wish to thank Dr. Kamhi his insightful commentary. Patient selection is a key to improved outcome. Relief of neurogenic claudication when sitting or during lumbar flexion is the most important consideration for patient selection. Others include patients over age 50, one- or two-level pathology, absence of severe osteoporosis, grade 1 or less spondylolisthesis.


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