471 - Comparative Effectiveness between Laminectomy with Fusion and Laminopl...

#471 Comparative Effectiveness between Laminectomy with Fusion and Laminoplasty for the Treatment of Multilevel Cervical Spondylotic Myelopathy

Value and Outcomes in Spine Surgery

Poster Presented by: H. Gould

Author(s):

H. Gould (1)
C. Haines (1)
E. Hu (1)
J. Miller (1)
R. Xiao (1)
T. Mroz (1)
D. Moore (1)

(1) Cleveland Clinic, Cleveland, OH, United States

Abstract

Introduction: The optimal management of multilevel cervical spondylotic myelopathy (CSM) remains unknown. Both laminectomy with fusion and laminoplasty have been demonstrated to offer a clinical benefit in small retrospective investigations. However, given the cost of spinal fusion, laminoplasty may represent a more cost-effective alternative that is equally efficacious.

Methods: A retrospective cohort study was conducted among patients undergoing cervical decompression for the treatment of multilevel CSM. The EQ-5D, PDQ, and PHQ-9 instruments were prospectively-collected between 2008 and 2015. These instruments served as measures of overall quality of life (QOL), pain-related disability, and depression. Postoperative QOL improvement exceeding the EQ-5D minimum clinically important difference (MCID) was the primary outcome. Secondary outcomes included the total surgical episode of care cost, PDQ MCID, and PHQ-9 MCID.
The surgical episode of care was defined in three periods: 30 days prior to admission, the index admission, and discharge to 365 days after admission. To present costs from the payer's perspective, costs were normalized to national Medicare reimbursement and presented in 2014 USD. Unpaired continuous and categorical data were compared via Wilcoxon rank-sum and Fisher's exact tests, while paired data were compared with Wilcoxon signed-rank tests. Multivariable logistic and log-transformed linear regression were used to model EQ-5D MCID and total episode of care costs.

Results: 186 patients were eligible for inclusion; among these, 142 (76%) underwent laminectomy with fusion, while 44 (24%) underwent laminoplasty. No significant differences in demographic or comorbid characteristics were observed. Preoperatively, the mean EQ-5D index was marginally greater in the laminoplasty cohort (0.530 vs. 0.581, p=0.17). Similarly, mean EQ-5D perceived health (41 vs. 50, p=0.06), PHQ-9 (4.7 vs. 2.9, p=0.20), and total PDQ (41 vs. 31, p=0.47) demonstrated poorer preoperative QOL in the laminectomy cohort. Within 30 days prior to admission, median disease-specific costs were not significantly different between cohorts ($818 vs. $716, p=0.21). However, median costs for the index admission were significantly greater among patients undergoing laminectomy ($25,888 vs. $19,427, p< 0.001).
Postoperatively, mean EQ-5D index improved to 0.592 (p=0.02) and 0.664 (p=0.01) in the laminectomy and laminoplasty cohorts, respectively. The proportion of patients achieving an EQ-5D MCID did not significantly differ between cohorts (36% vs. 30%, p=0.47). Following multivariable logistic regression, surgical type was not significantly associated with EQ-5D MCID (laminectomy vs. laminoplasty: OR 0.86, p=0.70). In the period following discharge, costs were not significantly different between cohorts ($3,450 vs. $3,424, p=0.46). However, total episode of care costs were greater in the laminectomy with fusion cohort ($34,718 vs. $25,260, p< 0.001). Following multivariable linear regression, total episode of care costs remained significantly greater in the laminectomy cohort (β = 0.572, p< 0.001), corresponding to a mean difference of $16,392.

Conclusions: Poorer preoperative QOL was observed among patients undergoing laminectomy with fusion relative to laminoplasty, and therefore these populations may differ with respect to expected surgical benefit. However, the proportion of patients achieving a clinically-relevant QOL improvement did not significantly differ, suggesting similar efficacy. After controlling for differences in baseline characteristics, laminoplasty appeared to be more cost-effective relative to laminectomy with fusion.