369 - Evaluating the Need for Non-randomized Training Cases: Experience from...

#369 Evaluating the Need for Non-randomized Training Cases: Experience from Patients Treated with the Investigational ACADIA® Device in a Clinical Trial

Oral Posters: Lumbar

Presented by: M.P. Lorio


J. Youssef (1)
J.J. Regan (2)
T. Briggs (3)
M.P. Lorio (4)
A.D. Tahernia (5)
D. Whiting (6)
S. Webb (7)
K. Baker (8)
J. Myer (9)

(1) Durango Orthopedic Associates/Spine Colorado, Durango, CO, USA
(2) DISC, Beverly Hills, CA, USA
(3) Springfield Neurological and Spine Institute, Springfield, MO, USA
(4) Neuro-Spine Solutions, Bristol, TN, USA
(5) Desert Orthopedic Center, Rancho Mirage, CA, USA
(6) Allegheny General Hospital, Pittsburgh, PA, USA
(7) Florida Spine Institute, Clearwater, FL, USA
(8) Globus Medical, Inc., Audubon, PA, USA
(9) Globus Medical, Inc., Clinical Affairs, Audubon, PA, USA


Purpose: An analysis of the preliminary outcomes in the ACADIA® clinical trial for the randomized and non-randomized investigational treatment cohorts at 24 months postoperative.

Methods: The ACADIA® Facet Replacement System (Globus Medical, Audubon, PA) is being evaluated in a randomized, prospective Investigational Device Exemption (IDE) pivotal study conducted at up to thirty sites across the U.S. Enrolled patients are randomized 2:1 to either the investigational ACADIA® system or the control PLF, with the option for two patients at each site treated as non-randomized training cases, receiving ACADIA®. Qualifying subjects must have degenerative lateral, lateral recess and/or central canal stenosis at a single level from L3 to S1 that requires decompression and facetectomy, and failed to improve with at least six cumulative months of conservative treatment. Outcome measures and radiographic evaluations are collected pre-operatively and at 6 weeks, 3, 6, 12 and 24 months post-operative. Individual success criteria include: improvement in ZCQ score by a minimum decrease of 0.5 versus baseline for both Symptom Severity (SS) and Physical Function (PF) scores; no subsequent surgical intervention at the level of treatment; maintenance or improvement in neurological outcome at 24 months; and no serious device-related adverse events. Outcomes are presented on 133 patients treated with ACADIA®, 109 randomized patients and 24 non-randomized patients.

Results: Both groups demonstrate improvement in mean VAS back and leg pain scores and mean ZCQ symptom severity and physical function scores at 24 months. The average VAS back pain score for randomized patients at 24 months was 20 ±23 as compared to 21 ±27 for non-randomized patients. Average VAS left leg pain for randomized patients was 13 ±22 versus 14 ±22 for non-randomized patients at 24 months. For the randomized patients, average VAS right leg pain was 14 ±23 at 24 months whereas the score for the non-randomized was 19 ±28. The average ZCQ SS score for randomized patients at 24 months is 1.9 ±0.7 as compared to 2.1 ±0.9 for non-randomized patients. In the randomized cohort, the average ZCQ PF is 1.6 ±0.6 versus 1.7 ±0.8 for non-randomized patients at 24 months. Average ZCQ satisfaction score for randomized patients is 1.5 ±0.7 as compared to 1.4 ±0.6 for non-randomized patients at 24 months. There was no substantial disparity in operative time and blood loss between the randomized and non-randomized cohorts. Average operative time was 138.1 ±73.0 minutes and 168.9 ±99.8 minutes, respectively. Average blood loss was 374.8 ±358.5 ml for randomized patients and 432.3 ±376.1 ml for non-randomized patients.

Conclusion: Preliminary 24 month outcomes and perioperative data are similar for the randomized and non-randomized groups. These data suggest that there may not be a significant learning curve associated with the utilization of the ACADIA® Facet Replacement System. However, there may be a benefit for surgeons to become familiar with the unique aspects of the investigational facet arthroplasty system.