Cost-Effectiveness of Corrective Fusion Surgeries for Adult Spinal Deformities

A Comparison by Operative Method

Hideyuki Arima, MD, PhD; Tomohiko Hasegawa, MD, PhD; Yu Yamato, MD, PhD; Masashi Kato, BS; Go Yoshida, MD, PhD; Tomohiro Banno, MD, PhD; Shin Oe, MD, PhD; Yuki Mihara, MD, PhD; Hiroki Ushirozako, MD, PhD; Tomohiro Yamada, MD; Yuh Watanabe, MD; Koichiro Ide, MD; Keiichi Nakai, MD; Kenta Kurosu, MD; Yukihiro Matsuyama, MD, PhD


Spine. 2021;46(18):1249-1257. 

In This Article

Abstract and Introduction


Study Design: Retrospective cohort study.

Objective: The aim of this study was to summarize the cost-effectiveness of surgical treatment for adult spinal deformity (ASD) according to the operative method over 2 years postoperatively.

Summary of Background Data: Extensive corrective fusion surgery for ASD requires numerous expensive implants, greatly contributing toward the national medical expenses. Previous national studies reported high complication rates in spinal surgeries using instrumentation. However, the cost-effectiveness of such procedures has not been scrutinized.

Methods: In total, 173 ASD patients (151 women; mean age 69.1 years) who underwent corrective fusion between 2010 and 2017 were included. Cost-effectiveness was evaluated according to the cost of obtaining 1 quality-adjusted life year (QALY). Patients were divided into three groups: the "corrective fusion surgery using multiple Grade 2 osteotomy" (Grade-2) group, three-column osteotomy group (three-column), and lateral lumbar interbody fusion (LLIF) group.

Results: The average medical cost for the initial surgery was USD 72,240, and that during the 2 years after the initial surgery was USD 76,294. The medical expenses for the initial surgery and those over the 2 years were higher in the LLIF group. The cumulative improvement in QALY over the 2 years did not significantly differ among the groups (0.13, 0.15, and 0.18 in the Grade-2, three-column, and LLIF groups, respectively). Cost/QALY 2 years after the surgery was USD 509,370, 518,406, and 463,798 in the Grade-2, three-column, and LLIF groups, respectively.

Conclusion: We summarized the medical costs and cost-effectiveness of three different surgical methods for ASD in patients with different backgrounds over 2 years postoperatively. The medical expense for the initial surgery was highest in the LLIF group, and the cumulative improvement in QALY over the 2 years tended to be higher in the LLIF group, but the difference was not significant; the overall cost-effectiveness was lowest in the LLIF group.

Level of Evidence: 3


Adult spinal deformity (ASD) includes pathological conditions such as remnants of idiopathic scoliosis, de novo kyphoscoliosis associated with disc degeneration, kyphosis after vertebral body fracture, and iatrogenic kyphosis after spinal fusion.[1,2] Associated symptoms include gait disorder, back pain, leg pain, visceral disorders, and psychological disorders.[1,3–5] Conservative treatments for moderate to severe ASD show poor efficacy, and surgical treatment is required to improve health-related quality of life (HRQOL) and gait disturbance.[6,7] Surgical treatment improves HRQOL more than conservative treatments.[8] Surgical treatment for ASD requires posterior spinal fusion from the thoracic spine to the pelvis.[9] This extensive posterior corrective fusion may provide treatment, but the financial burden is comparable to implants. Previous national surveys reported a high incidence of complications in spinal surgeries using spinal instrumentation.[10] Therefore, it is important to clarify the cost-effectiveness of the expensive and extensive corrective fusion surgeries for ASD. Recently, ASD surgical treatments are reported as more cost-effective than conservative treatments 4 and 5 years postoperatively.[11] Corrective fusion using multiple Grade 2 osteotomy or three-column osteotomy (Grade 4 or 5) may be used depending on the pathological condition.[12] The usefulness of staged surgeries using lateral lumbar interbody fusion (LLIF) has also been reported.[13] The cost-effectiveness of each procedure has not yet been scrutinized. This study summarizes the cost-effectiveness of surgical treatment for ASD by operative method over 2 years postoperatively.