The First Grade III Lumbar Spondylolisthesis Treated With the Novel 360° Artificial Disc/Artificial Facet Replacement Solution.

Background: The incidence of spondylolisthesis increases with age and is more prevalent in women. "High-grade" (above grade II) occurs in 10% to 12% of affected individuals. Patients often present with back pain as well as leg pain, numbness, paresthesias, hamstring tightness, radiculopathy, and neurogenic claudication. If conservative therapy fails , the standard of care is fusion. However, despite its effectiveness in stabilizing the spine, fusion causes biomechanical load transfer to adjacent vertebrae, which can increase the risk of adjacent segment disease and reduce range of motion. These drawbacks are especially problematic for younger, more active patients who wish to maintain a high quality of life. In this report, we describe an innovative 360º, motion-preserving surgical approach utilizing 2 FDA-approved devices, the Prodisc L Artificial Disc Replacement and the Total Posterior Spine System, in an "off-label" investigational manner for the treatment of high-grade spondylolisthesis and associated disc space collapse.

Methods: This case report is part of a multi-institution, Institutional Review Board-approved, prospective cohort trial. Subjective and objective outcomes were collected every 6 to 12 weeks. Patient satisfaction scores as well as patient-reported outcomes included neurologic examination, visual analog scale (VAS) back pain, VAS left leg pain, VAS right leg pain, Patient-Reported Outcomes Measurement Information System (PROMIS), PROMIS physical health, PROMIS mental health, 12-item short form (SF-12), need for repeat surgery, patient's recommendations pertaining to their surgery, and postoperative radiographic dynamic x-ray images. A 36-year-old man presented to the clinic with complaints of progressive 7 to 8/10 low back pain with pain radiating down his legs bilaterally. The patient reported years of symptoms, only mildly managed with conservative therapy. He had been offered fusion by multiple surgeons. Imaging demonstrated progression of his known L5 to S1 grade II spondylolisthesis with severe disc space collapse to now grade III.

Results: The patient's Oswestry Disability Index improved from 16 to 2 (87.5%) at 3 months postoperatively. The patient's VAS score for back, left, and right leg pain was 4.87, 2.41, and 1.51 preoperatively. All VAS scores decreased to 0 by 3 months. The PROMIS physical health score of 14 remained relatively stable at 13 at 3 months. The SF-12 physical and mental component scores improved by 16.7% and 21.23%, respectively. By 6 weeks postoperation, the patient expressed high satisfaction of 8 out of 10, improving to 10 out of 10 by 3 months. Results have been maintained at 9 months.

Conclusion: This case illustrates encouraging early data in support of a 360º arthroplasty concept in the treatment of high-grade spondylolisthesis.

Clinical relevance: This cutting-edge motion preservation work has the possibility of changing the landspace of spine surgery. The hope is that the technology and methodology provide an option for patients who would otherwise almost unequivocally undergo fusion.

Level of evidence: 5: