#241 Prevalence of Spondylolisthesis and Concomitant Adolescent Idiopathic Scoliosis: A Matched Cohort Analysis

General Session: What's New in Biologics and Biomechanics

Presented by: R. Tracey

Author(s):

R.A. Lehman (1)
D.G. Kang (1)
L.G. Lenke (2)
K. Blanke (2)
E.E. Transfeldt (3)
H. Labelle (4)
S. Parent (4)
J. Cody (1)
J.-M. Mac-Thiong (4)
R.W. Tracey (1)
Spinal Deformity Study Group

(1) Walter Reed National Military Medical Center, Orthopaedic Surgery, Bethesda, MD, USA
(2) Washington University School of Medicine, Orthopaedic Surgery, St Louis, MO, USA
(3) Twin Cities Spine Center, Minneapolis, MN, USA
(4) CHU Saint-Justine Research Center, Universite de Montreal, Montreal, QC, Canada

Abstract

Introduction: The association of spondylolisthesis and adolescent idiopathic scoliosis (AIS) has never been thoroughly evaluated. Failure to appropriately identify a concomitant spinal disorder may result in inappropriate treatment and suboptimal outcomes. We set out to determine the prevalence of patients with both spondylolisthesis and AIS, and to evaluate clinical outcomes following surgical treatment for only one of the concomitant conditions.

Methods: A prospective, multicenter database of patients evaluated/treated for a primary diagnosis of adolescent idiopathic scoliosis or spondylolisthesis was reviewed. All available pre-operative radiographs were evaluated for the presence of both AIS and spondylolisthesis. In addition to radiographic analysis, SRS-22 questionnaire responses were evaluated at baseline and at 2-year follow-up. Patients were analyzed in three groups, which included: Group I - AIS patients requiring fusion (n=1132); Group II - symptomatic spondylolisthesis requiring fusion (n=66); and Group III - asymptomatic spondylolisthesis (n=149). A matched cohort analysis (Group 1: age, gender, Lenke curve type, curve magnitude and amount of curve correction; Group 2: age, gender, Meyerding slip grade) was performed to evaluate the clinical outcomes of patients without a concomitant spinal disorder.

Results: There were a total of 1,347 patients identified in the database review; however adequate pre-operative radiographs were available for 1,266 patients. In Group I, adequate radiographs were available for 1076 patients, and 47 (4.38%) were found to have concomitant spondylolisthesis. In Group II, adequate radiographs were available for 48 patients, and 14 (29.2%) were found to have concomitant true scoliosis, as well as 9 (13.6%) with sciatic scoliosis. In Group 3, adequate radiographs were available for 142 patients, and 28 (19.7%) were found to have concomitant true scoliosis, as well as 13 (9.2%) with sciatic scoliosis.

There was no difference in demographics between Group 1and 2 and their respective matched cohorts (AIS treated surgically without spondy and spondy treated surgically without AIS, respectively). There was no significant difference in all components and total SRS outcome score between Group 1 and the matched cohort, with similar findings between Group 2 and the matched cohort.

Discussion and Conclusion: Our study found symptomatic and asymptomatic spondylolisthesis are associated with concomitant scoliosis in approximately 20-30% of patients. In contrast, the prevalence of AIS requiring fusion with concomitant spondylolisthesis was relatively uncommon (4.4%). In the presence of coexistent spondylolisthesis and AIS, to achieve similar clinical outcomes, each may be treated independently and according to their individual surgical indications.