440 - Comparative Effectiveness and Cost-utility of a Novel Annular Closure...

#440 Comparative Effectiveness and Cost-utility of a Novel Annular Closure Device for Prevention of Recurrent Disc Herniation Following Lumbar Discectomy: A Prospective Cohort Study

Oral Posters: Quality of Spine Care

Presented by: S. Parker

Author(s):

S.L. Parker (1)
G. Grahovac (2)
D. Vukas (3)
D. Ledic (3)
M. Vilendecic (2)
M.J. McGirt (1)

(1) Vanderbilt University Medical Center, Neurological Surgery, Nashville, TN, USA
(2) University Hospital, Neurological Surgery, Dubrava, Croatia
(3) University Hospital, Neurological Surgery, Rijeka, Croatia

Abstract

Objective: Same-level recurrent disc herniation, disc height loss, and progressive degeneration are common complications and sequellae after lumbar discectomy. Techniques to reduce these consequences may improve outcomes after lumbar discectomy. In a prospective cohort study, we evaluated if an annular closure device could be implanted safely, reduce same-level recurrent disc herniation, attenuate disc height loss, and/or improve outcome after lumbar discectomy. Additionally, we evaluated the cost-utility of this device.

Methods: Forty-six consecutive patients undergoing lumbar discectomy for single-level herniated disc were prospectively followed with clinical and radiographic evaluations at 6 weeks and 3, 6, 12 and 24 months (control cohort). A second consecutive cohort of 31 lumbar discectomies with implantation of an annular closure device was followed similarly. Incidence of recurrent disc herniation, disc height loss, leg and back pain visual analogue scale (VAS), Oswestry Disability Index (ODI), and SF-6D were assessed at each follow-up. Two-year cost estimates were based on Medicare national allowable payment amounts (direct cost) and patient work-day losses (indirect cost). Difference in mean total cost per QALY gained for annular closure versus control was assessed as incremental cost-effectiveness ratio (ICER).

Results: By two-years follow-up, symptomatic recurrent same-level disc herniation occurred in 3 (6.5%) patients in the control cohort versus 0 (0%) patients in the annular repair cohort (p=0.27). A trend of greater preservation of disc height was observed in the annular repair cohort three months (7.9 vs. 7.27mm, p=0.08), six months (7.81 vs. 7.18mm, p=0.09), and twelve months post-operatively (7.63 vs. 6.9mm, p=0.06). Annular closure cohort reported less leg pain (p< 0.01), back pain (p< 0.05), and disability (p< 0.05) post-operatively, Figure 1. Mean cumulative two-year QALY gain for patients in the annular closure cohort (0.69) was greater than the control cohort (0.39), p< 0.01. Using U.S. private payer cost estimates, the mean total two-year cost for surgical treatment of disc herniation in the annular closure and control cohort was $37,142 vs. $36,474, respectively, Figure 2. ICER associated with use of annular closure device was $2,227 per QALY-gained.

Conclusions: Implantation of a novel annular repair device was associated with greater maintenance of disc height and improved one-year pain, disability, and quality of life. Secondary to the increased cost associated with revision surgery and less SF-6D improvement in the control cohort, the novel annular closure device represented a cost effective advancement in the setting of lumbar discectomy for disc herniation, with an ICER of $2,227 per QALY-gained. Development of novel techniques to prevent recurrent lumbar disc herniation is warranted to decrease the associated morbidity and healthcare costs.

Figure 1

Figure 2