1 Department of Orthopedic Surgery, Taleghani Hospital, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran

2 Department of Orthopedic Surgery, Mofid Children Hospital, School of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran

3 Robert Debre Hospital, Paris 7 University, Paris, France


To determine the most important preoperative factors that affect postoperative coronal parameters of scoliotic curves.
All Adolescent Idiopathic Scoliosis (AIS) patients included in the study were classified according to Lenke and King Classification. The fusion levels were selected according to the rigidity of the existing curves (correction less than 50%), tilt of T1 and shoulders, sagittal angle of the curves and with considering stable and neutral end vertebra. The radiographic coronal parameters: shoulders tilt angle, iliolumbar angle and coronal balance were measured in all patients before, after, and in the last follow- up visit.
One hundred twenty patients after mean of 25 months follow-up (18-40 months) were included in the study. Before operation, abnormal coronal balance (more than 2 cm shift) was noticed in 46 patents (38%) and in the last visit, was noted in 22 patients (18%). Multivariate regression analysis revealed a significant predictive value of the preoperative coronal balance on the last visit coronal balance (P value=0.01).
Preoperative coronal balance is very important to make a balanced spine after surgery. Other parameters like Lenke classification or main thoracic overcorrection did not affect postoperative coronal decompensation.


1. Lenke LG, Bridwell KH, Baldus C, Blanke K.
Preventing decompensation in King type II curves
treated with Cotrel-Dubousset instrumentation.
Strict guidelines for selective thoracic fusion. Spine.
1992; 17(8 Suppl):274-81.
2. Frez R, Cheng JC, Wong EM. Longitudinal changes
in trunkal balance after selective fusion of King II
curves in adolescent idiopathic scoliosis. Spine.
2000; 25(11):1352-9.
3. Lenke CL. SRS Terminology committee and working
group on spinal classification. Revised Glossary of
Terms. Scoliosis Research Society, Milwaukee, US; 2000.
4. Harrington PR. Treatment of scoliosis. Correction
and internal fixation by spine instrumentation. J
Bone Joint Surg Am. 1962; 44(4):591-610.
5. Lenke LG, Betz RR, Harms J, Bridwell KH, Clements DH,
Lowe TG, et al. Adolescent idiopathic scoliosis: a new
classification to determine extent of spinal arthrodesis.
J Bone Joint Surg Am. 2001; 83(8):1169-81.
6. King HA. Selection of fusion levels for posterior
instrumentation and fusion in idiopathic scoliosis.
Orthop Clin North Am. 1988; 19(2):247-55.
7. Richards BS, Scaduto A, Vanderhave K, Browne R.
Assessment of trunk balance in thoracic scoliosis.
Spine. 2005; 30(14):1621-6.
8. Majdouline Y, Aubin CE, Robitaille M, Sarwark
JF, Labelle H. Scoliosis correction objectives in
adolescent idiopathic scoliosis. J Pediatr Orthop.
2007; 27(7):775-81.
9. McCance SE, Denis F, Lonstein JE, Winter RB. Coronal
and sagittal balance in surgically treated adolescent
idiopathic scoliosis with the King II curve pattern:
a review of 67 consecutive cases having selective
thoracic arthrodesis. Spine. 1998; 23(19):2063-73.
10. Demura S, Yaszay B, Bastrom TP, Carreau J, Newton
PO, Harms Study Group. Is decompensation
preoperatively a risk in Lenke 1C curves? Spine.
2013; 38(11):E649-55.
11. Moore MR, Baynham GC, Brown CW, Donaldson DH,
Odom JA Jr. Analysis of factors related to truncal
decompensation following Cotrel-Dubousset
instrumentation. J Spinal Disord. 1991; 4(2):188-92.
12. Gomez JA, Matsumoto H, Colacchio ND, Roye
DP, Sucato DJ, Richards BS, et al. Risk factors for

coronal decompensation after posterior spinal
instrumentation and fusion in adolescent idiopathic
scoliosis. Spine Deform. 2014; 2(5):380-5.
13. Chang KW, Chang KI, Wu CM. Enhanced Capacity
for spontaneous correction of lumbar curve in
the treatment of major thoracic–compensatory
C modifier lumbar curve pattern in idiopathic
scoliosis. Spine. 2007; 32(26):3020-9.
14. Arlet V, Marchesi D, Papin P, Aebi M. Decompensation
following scoliosis surgery: treatment by decreasing
the correction of the main thoracic curve or “letting
the spine go”. Eur Spine J. 2000; 9(2):156-60.
15. Liu Z, Guo J, Zhu Z, Qian B, Sun X, Xu L, et al. Role

of the upper and lowest instrumented vertebrae
in predicting the postoperative coronal balance in
Lenke 5C patients after selective posterior fusion.
Eur Spine J. 2013; 22(11):2392-8.
16. Ishikawa M, Cao K, Pang L, Watanabe K, Yagi M, Hosogane
N, et al. Postoperative behavior of thoracolumbar/
lumbar curve and coronal balance after posterior
thoracic fusion for Lenke 1C and 2C adolescent
idiopathic scoliosis. J Orthop Sci. 2015; 20(1):31-7.
17. Ward WT, Rihn JA, Solic J, Lee JY. A comparison of the
Lenke and King classification systems in the surgical
treatment of idiopathic thoracic scoliosis. Spine.
2008; 33(1):52-60.