466 - Does Treatment with the ACADIA® Facet Replacement System Provide Susta...

#466 Does Treatment with the ACADIA® Facet Replacement System Provide Sustained Relief of Symptomatic Lumbar Spinal Stenosis?

Lumbar Therapies and Outcomes

Poster Presented by: J. Regan


J. Regan (1)
F. Siddiqi (2)
M. Lorio (3)
B. Sachs (4)
K. Baker (5)
J. Myer (5)

(1) Spine Group Beverly Hills, Beverly Hills, CA, United States
(2) Trinity Spine Center, Tampa, FL, United States
(3) Neuro Spine Solutions, Bristol, TN, United States
(4) Medical University of South Carolina, Charleston, SC, United States
(5) Globus Medical, Inc., Audubon, PA, United States


Purpose: A common and potentially disabling cause of pain in the lower back and legs is lumbar spinal stenosis (LSS). Facet arthroplasty may offer patients suffering from neurogenic intermittent claudication secondary to LSS the potential benefits of pain relief while preserving stability and motion.

Methods: A prospective, randomized, multi-center IDE study evaluating the ACADIA® Facet Replacement System (Globus Medical, Audubon, PA) is being conducted at up to 30 sites across the U.S. Patients are randomized 2:1 to treatment using either the investigational ACADIA® or control instrumented posterolateral fusion (PLF). Candidates for inclusion must have degenerative lateral, lateral recess and/or central canal stenosis at a single level from L3 to S1 that requires decompression and facetectomy, failed to improve with at least six cumulative months of conservative treatment, scored greater than 2 on the ZCQ Symptom Severity (SS) score and scored greater than or equal to 2 on the ZCQ Physical Function (PF) score. Primary endpoint success criteria include: improvement in ZCQ (>0.5); no subsequent surgical intervention; maintenance or improvement in neurological status at 24 months; and no serious device-related adverse events. The ZCQ patient questionnaire is completed at pre-op, 6 weeks, 3, 6, 12, 24 months and annually thereafter. Data are presented from 213 randomized patients: 141 ACADIA® and 72 PLF patients.

Results: Both cohorts demonstrated improvement in mean ZCQ scores for SS, PF and satisfaction. In patients treated with ACADIA®, the average ZCQ SS score improved from 3.6 at pre-op to 1.9, 2.1 and 1.5 at 24mo, 36mo and 48mo, respectively, as compared PLF patients from 3.7 at pre-op to 2.1, 2.1 and 1.2 at 24mo, 36mo and 48mo, respectively. Mean ZCQ PF scores improved from 2.8 at pre-op to 1.5, 1.7 and 1.3 at 24mo, 36mo and 48mo, respectively, for the ACADIA® cohort, versus PLF patients who improved from 2.8 pre-op to 1.7, 1.7 and 1.1 at 24mo, 36mo, and 48mo post-op, respectively. ZCQ satisfaction scores suggest that patients treated with ACADIA® are satisfied with the results of their surgery. The ACADIA® cohort showed mean ZCQ satisfaction scores of 1.4 at 24mo, 1.6 at 36mo, and 1.2 at 48mo as compared to the PLF cohort with 1.6 at 24mo, 1.6 at 36mo, and 1.3 at 48mo post-op. Subsequent surgical intervention has occurred in 7.1% of ACADIA® and 6.9% of PLF patients.

Conclusion: Improvement in ZCQ SS and PF scores was observed in both treatment cohorts. These preliminary results indicate that both groups show similar functional improvement with respect to the ZCQ, a measure of pain, function, and satisfaction. These study results also suggest that facet arthroplasty using the ACADIA® Facet Replacement System may be a viable alternative to an instrumented posterolateral fusion for the treatment of symptomatic lumbar spinal stenosis.