TY - JOUR
T1 - Risk factors for the development of DJK in AIS patients undergoing posterior spinal instrumentation and fusion
AU - Harms Study Group
AU - Segal, Dale N.
AU - Ball, Jacob
AU - Fletcher, Nicholas D.
AU - Yoon, Eric
AU - Bastrom, Tracey
AU - Vitale, Michael G.
AU - Buckland, Aaron
AU - Samdani, Amer
AU - Jain, Amit
AU - Lonner, Baron
AU - Roye, Benjamin
AU - Yaszay, Burt
AU - Reilly, Chris
AU - Hedequist, Daniel
AU - Sucato, Daniel
AU - Clements, David
AU - Miyanji, Firoz
AU - Shufflebarger, Harry
AU - Flynn, Jack
AU - Asghar, John
AU - Thiong, Jean Marc Mac
AU - Pahys, Joshua
AU - Harms, Juergen
AU - Bachmann, Keith
AU - Lenke, Lawrence
AU - Karol, Lori
AU - Abel, Mark
AU - Erickson, Mark
AU - Glotzbecker, Michael
AU - Kelly, Michael
AU - Marks, Michelle
AU - Gupta, Munish
AU - Fletcher, Nicholas
AU - Larson, Noelle
AU - Cahill, Patrick
AU - Sponseller, Paul
AU - Gabos, Peter
AU - Newton, Peter
AU - Betz, Randal
AU - Parent, Stefan
AU - George, Stephen
AU - Hwang, Steven
AU - Shah, Suken
AU - Garg, Sumeet
AU - Errico, Tom
AU - Upasani, Vidyadhar
N1 - Publisher Copyright:
© 2021, Scoliosis Research Society.
PY - 2022/3
Y1 - 2022/3
N2 - Purpose: Typically, selection of lowest instrumented vertebra (LIV) in Adolescent Idiopathic Scoliosis (AIS) is based on the coronal radiograph; however, increasing evidence suggests that fusions proximal to the stable sagittal vertebrae (SSV) on the lateral radiograph can result in distal junctional kyphosis (DJK). The purpose of this study is to compare rates of DJK in patients with AIS that have a discordance between the Lowest Touched Vertebra (LTV) and the SSV and to identify risk factors for developing DJK. Methods: Patients with AIS Lenke type 1, 2 and 3 curves treated with a posterior spinal fusion were separated into two groups. Group 1 had SSV that was proximal to the LTV whereas group 2 had SSV that was distal to the LTV. Comparisons were made for patients that were fused to the SSV(a), LTV(b) or between(c). Distal junctional angle (DJA) > 5° and increasing kyphosis at the end of the fusion construct were evaluated as risk factors for DJK. Results: The rate of DJK was 0.0% in group 1a, 1b, and 1c compared to 4.3%, 18.5% and 10.0% in groups 2a, 2b and 2c, respectively(p < 0.001). The rate of DJK was 22.9% when the distal junctional angle(DJA) > 5° versus 1.4% when the DJA < 5°(p < 0.001). Conclusion: There was a low risk for progression of DJK when the SSV was proximal to the LTV, however, those with SSV distal to the LTV represent a high-risk group. Importantly, the development of DJK occurred almost exclusively in patients with LIV at the thoracolumbar junction which demonstrates that surgeons need to be cautious when ending fusions at T11, T12, and L1 in patients at high risk for DJK. Furthermore, having a distal junctional angle 5° or greater increased the risk of developing DJK by roughly 16-fold. At a minimum of 5-year follow-up, the development of DJK did not appear to adversely impact SRS outcomes or revision rates.
AB - Purpose: Typically, selection of lowest instrumented vertebra (LIV) in Adolescent Idiopathic Scoliosis (AIS) is based on the coronal radiograph; however, increasing evidence suggests that fusions proximal to the stable sagittal vertebrae (SSV) on the lateral radiograph can result in distal junctional kyphosis (DJK). The purpose of this study is to compare rates of DJK in patients with AIS that have a discordance between the Lowest Touched Vertebra (LTV) and the SSV and to identify risk factors for developing DJK. Methods: Patients with AIS Lenke type 1, 2 and 3 curves treated with a posterior spinal fusion were separated into two groups. Group 1 had SSV that was proximal to the LTV whereas group 2 had SSV that was distal to the LTV. Comparisons were made for patients that were fused to the SSV(a), LTV(b) or between(c). Distal junctional angle (DJA) > 5° and increasing kyphosis at the end of the fusion construct were evaluated as risk factors for DJK. Results: The rate of DJK was 0.0% in group 1a, 1b, and 1c compared to 4.3%, 18.5% and 10.0% in groups 2a, 2b and 2c, respectively(p < 0.001). The rate of DJK was 22.9% when the distal junctional angle(DJA) > 5° versus 1.4% when the DJA < 5°(p < 0.001). Conclusion: There was a low risk for progression of DJK when the SSV was proximal to the LTV, however, those with SSV distal to the LTV represent a high-risk group. Importantly, the development of DJK occurred almost exclusively in patients with LIV at the thoracolumbar junction which demonstrates that surgeons need to be cautious when ending fusions at T11, T12, and L1 in patients at high risk for DJK. Furthermore, having a distal junctional angle 5° or greater increased the risk of developing DJK by roughly 16-fold. At a minimum of 5-year follow-up, the development of DJK did not appear to adversely impact SRS outcomes or revision rates.
KW - Adolescent idiopathic scoliosis
KW - Distal junctional kyphosis
KW - Posterior spinal fusion
KW - Stable sagittal vertebra
UR - http://www.scopus.com/inward/record.url?scp=85124578347&partnerID=8YFLogxK
U2 - 10.1007/s43390-021-00413-4
DO - 10.1007/s43390-021-00413-4
M3 - Article
C2 - 34529249
AN - SCOPUS:85124578347
SN - 2212-134X
VL - 10
SP - 377
EP - 385
JO - Spine Deformity
JF - Spine Deformity
IS - 2
ER -