We describe a modified fulcrum design to overcome limitations of a traditional fulcrum. The modified fulcrum is a triangular prism–shaped foam with rounded and padded edges. The 3 faces of the fulcrum represent 3 different heights (17.0 cm, 17.5 cm, and 21.0 cm). For fulcrum bending radiographs of the thoracic curve, the patient is placed on an X-ray table in a lateral decubitus position over the fulcrum. The apex of the appropriate height of the fulcrum is positioned under the rib corresponding to the apex of the curve, such that the ipsilateral shoulder is lifted off the X-ray table for maximum passive bending force to the curve. For fulcrum bending radiographs of the lumbar curve, the fulcrum is positioned directly under the apex of the curve such that the ipsilateral iliac crest is lifted off the X-ray table.
CheungKMLukKD. Prediction of correction of scoliosis with use of the fulcrum bending radiograph. J Bone Joint Surg Am1997;79:1144–50.
2.
HamzaogluATaluUTezerMMirzanliCDomanicUGoksanSB. Assessment of curve flexibility in adolescent idiopathic scoliosis. Spine (Phila Pa 1976)2005;30:1637–42.
3.
ByrdJA3rdScolesPVWinterRBBradfordDSLonsteinJEMoeJH. Adult idiopathic scoliosis treated by anterior and posterior spinal fusion. J Bone Joint Surg Am1987;69:843–50.
4.
LargeDFDoigWGDickensDRTorodeIPColeWG. Surgical treatment of double major scoliosis. Improvement of the lumbar curve after fusion of the thoracic curve. J Bone Joint Surg Br1991;73:121–4.
5.
McCallREBronsonW. Criteria for selective fusion in idiopathic scoliosis using Cotrel-Dubousset instrumentation. J Pediatr Orthop1992;12:475–9.
6.
VaughanJJWinterRBLonsteinJE. Comparison of the use of supine bending and traction radiographs in the selection of the fusion area in adolescent idiopathic scoliosis. Spine (Phila Pa 1976)1996;21:2469–73.
7.
KleinmanRGCsongradiJJRinksyLABleckEE. The radiographic assessment of spinal flexibility in scoliosis: A study of the efficacy of the prone push film. Clin Orthop Relat Res1982;162:47–53.
8.
VedantamRLenkeLGBridwellKHLinvilleDL. Comparison of push-prone and lateral-bending radiographs for predicting postoperative coronal alignment in thoracolumbar and lumbar scoliotic curves. Spine (Phila Pa 1976)2000;25:76–81.
9.
Duval-BeaupereGLespargotAGrossiordA. Flexibility of scoliosis. What does it mean? Is this terminology appropriate?Spine (Phila Pa 1976)1985;10:428–32.
10.
PollyDWJrSturmPF. Traction versus supine side bending. Which technique best determines curve flexibility?Spine (Phila Pa 1976)1998;23:804–8.
11.
CheungKMLuDSZhangHLukKD. In-vivo demonstration of the effectiveness of thoracoscopic anterior release using the fulcrum-bending radiograph: A report of five cases. Eur Spine J2006;15(Suppl 5):578–82.
12.
CheungKMNatarajanDSamartzisDWongYWCheungWYLukKD. Predictability of the fulcrum bending radiograph in scoliosis correction with alternate-level pedicle screw fixation. J Bone Joint Surg Am2010;92:169–76.
13.
CheungKMWuJPChengQHMaBSGaoJCLukKD. Treatment of stiff thoracic scoliosis by thoracoscopic anterior release combined with posterior instrumentation and fusion. J Orthop Surg Res2007;2:16.
14.
CheungWYLenkeLGLukKD. Prediction of scoliosis correction with thoracic segmental pedicle screw constructs using fulcrum bending radiographs. Spine (Phila Pa 1976)2010;35:557–61.
15.
LiJDumonskiMLSamartzisDHongJHeSZhuX. Coronal deformity correction in adolescent idiopathic scoliosis patients using the fulcrum-bending radiograph: A prospective comparative analysis of the proximal thoracic, main thoracic, and thoracolumbar/lumbar curves. Eur Spine J2011;20:105–11.
16.
LukKDCheungKMLuDSLeongJC. Assessment of scoliosis correction in relation to flexibility using the fulcrum bending correction index. Spine (Phila Pa 1976)1998;23:2303–7.
17.
LukKDDonASChongCSWongYWCheungKM. Selection of fusion levels in adolescent idiopathic scoliosis using fulcrum bending prediction: A prospective study. Spine (Phila Pa 1976)2008;33:2192–8.
18.
LukKDLuDSCheungKMWongYW. A prospective comparison of the coronal deformity correction in thoracic scoliosis using four different instrumentations and the fulcrum-bending radiograph. Spine (Phila Pa 1976)2004;29:560–3.
19.
LukKDVidyadharaSLuDSWongYWCheungWYCheungKM. Coupling between sagittal and frontal plane deformity correction in idiopathic thoracic scoliosis and its relationship with postoperative sagittal alignment. Spine (Phila Pa 1976)2010;35:1158–64.
20.
SunYQSamartzisDCheungKMWongYWLukKD. The “X-Factor” index: A new parameter for the assessment of adolescent idiopathic scoliosis correction. Eur Spine J2011;20:144–50.
21.
FeiQWangYPQiuGXZhaoYShenJXZhangJG. Assessment of curve flexibility in adolescent idiopathic scoliosis before operation [in Chinese]. Zhonghua Yi Xue Za Zhi2007;87:2484–8.
22.
HayDIzattMTAdamCJLabromRDAskinGN. The use of fulcrum bending radiographs in anterior thoracic scoliosis correction: A consecutive series of 90 patients. Spine (Phila Pa 1976)2008;33:999–1005.
23.
IbrahimTGabbarOAEl-AbedKHutchinsonMJNelsonIW. The value of radiographs obtained during forced traction under general anaesthesia in predicting flexibility in idiopathic scoliosis with Cobb angles exceeding 60 degree. J Bone Joint Surg Br2008;90:1473–6.
24.
KleppsSJLenkeLGBridwellKHBassettGSWhortonJ. Prospective comparison of flexibility radiographs in adolescent idiopathic scoliosis. Spine (Phila Pa 1976)2001;26:E74–9.
25.
LittleJPAdamC. Towards determining soft tissue properties for modelling spine surgery: Current progress and challenges. Med Biol Eng Comput2012;50:199–209.
26.
LittleJPAdamCJ. The effect of soft tissue properties on spinal flexibility in scoliosis: Biomechanical simulation of fulcrum bending. Spine (Phila Pa 1976)2009;34:E76–82.
27.
LoweTGAlongiPRSmithDAO'BrienMFMitchellSLPintericRJ. Anterior single rod instrumentation for thoracolumbar adolescent idiopathic scoliosis with and without the use of structural interbody support. Spine (Phila Pa 1976)2003;28:2232–42.
