Analysis of Cost Utility of Distal Junctional Kyphosis Occurrence after Adult Cervical Deformity Surgery: The Benefit of Prophylaxis and Preoperative Optimization

Thursday, June 1, 2023

8:30 AM – 6:15 PM

Location: Salons 7-8

Co-Author(s)

PD

Pooja R. Dave

Miami, Florida, United States
JM

Jamshaid M. Mir, MD

Research Fellow
NYU Langone Health | NY Spine Institute, United States
PT

Peter S. Tretiakov, BS

United States
OO

Oluwatobi Onafowokan

United Kingdom
MJ

M. Burhan Janjua

United States
SV

Shaleen Vira, MD

Assistant Professor, Orthopaedic Surgery & Neurosurgery
UT Southwestern Medical Center
Dallas, Texas, United States
AS

Andrew Schoenfeld

United States
TR

Timothy Roberts

Orthopaedic Spine Surgeon
Westbury, New York, United States
AM

Angel Macagno

United States
AD

Alexandre Demoura

United States

Presenting Author (Person doing the Podium Present(s)

PP

Peter G. Passias, M.D.

Spine Surgeon
NYU Langone Orthopedic Hospital
New York, New York, United States

View E-Poster

Submitter(s)

PP

Peter G. Passias, M.D.

Spine Surgeon
NYU Langone Orthopedic Hospital
New York, New York, United States

View E-Poster

Disclosure(s):

Peter G. Passias, MD: No relevant disclosure to display

Introduction: Prior studies have analyzed the predictive presence of distal junctional kyphosis and failure after adult spinal deformity surgery. However, there remains a gap in the cost utility of DJK and prophylactic efficacy in prevention.

Methods: Operative CD patients with up to 2Y data included. Preoperative optimization for osteoporosis was assessed by treatment with an FDA approved drug prior to surgery (OptO). Preoperative rehabilitation (Prehab) was also assessed. Cost analysis was based on average Medicare reimbursement while accounting for surgical approach and revision status. Reimbursement consisted of a standardized estimate using regression analysis of Medicare pay-scales for services within a 30 day window. All costs were inflation adjusted to 2022. For QALY analysis, utility was calculated using EQ-5D as previously published. Multivariate regression analysis noted predictive factors to development of DJK related to prophylaxis, adjusting for covariates including age, baseline deformity, and baseline EQ5D.

Results: 136 met inclusion (57.1±9.5yrs, 60%F, BMI 28.6±6.7kg/m2, CCI: .58±1.0). 24 (22%) developed DJK within 2Y postoperatively, with 6 patients (6%) undergoing revision surgery. Multivariate analysis confirmed Prehab patients more likely to improve in ODI (OR .055 [CI .006-.476], p=.008) at 2Y. However, Prehab and no Prehab patients exhibited similar ODI IHS recovery rates from BL to 2Y, P<.05. Total cost for Prehab patients was $59,272 compared to $72,878 for not Prehab, P<.05. Cost effectiveness was determined via cost per QALY: Prehab = $14,463 and not Prehab = $45,515, P<.05. For osteoporosis (85.4% Opt), Opt patients had lower odds of 2Y complications (OR: 0.207 [.086, .498],p <.001) and lower cost ($28,053 vs. $33,171,p=.002) compared to non-optimized patients. Average cost of revision surgery due to DJK within 2Y of index surgery was $50,736 ± 31,467, and average cost of index surgery was $44,418. By 2Y, the NDI for DJK patients was (48 vs 37, p=.026) showing a greater improvement in disability for non-DJK patients. When factoring in the improvement and looking at additional cost of QALY by 2Y, the total cost for DJK patients was $89,259 vs $64,973 compared to those optimized.

Conclusion: The presence of DJK after adult spinal deformity surgery leads to greater surgical cost with lower patient-reported outcomes and greater odds of revision surgery. Although preoperative optimization may increase upfront costs to primary surgery, it presents greater cost utility benefit to prevent the development of DJK and later revision surgery.