Spontaneous improvement of cervical alignment after correction of global sagittal balance following pedicle subtraction osteotomy

Presented at the 2012 Joint Spine Section Meeting 

Restricted access


Sagittal spinopelvic malalignment is a significant cause of pain and disability in patients with adult spinal deformity. Surgical correction of spinopelvic malalignment can result in compensatory changes in spinal alignment outside of the fused spinal segments. These compensatory changes, termed reciprocal changes, have been defined for thoracic and lumbar regions but not for the cervical spine. The object of this study was to evaluate postoperative reciprocal changes within the cervical spine following lumbar pedicle subtraction osteotomy (PSO).


This was a multicenter retrospective radiographic analysis of patients from International Spine Study Group centers. Inclusion criteria were as follows: adults (>18 years old) with spinal deformity treated using lumbar PSO, a preoperative C7–S1 plumb line greater than 5 cm, and availability of pre- and postoperative full-length standing radiographs.


Seventy-five patients (60 women, mean age 59 years) were included. The lumbar PSO significantly improved sagittal alignment, including the C7–S1 plumb line, C7–T12 inclination, and pelvic tilt (p <0.001). After lumbar PSO, reciprocal changes were seen to occur in C2–7 cervical lordosis (from 30.8° to 21.6°, p <0.001), C2–7 plumb line (from 27.0 mm to 22.9 mm), and T-1 slope (from −38.9° to −30.4°, p <0.001). Ideal correction of sagittal malalignment (postoperative sagittal vertical alignment < 50 mm) was associated with the greatest relaxation of cervical hyperlordosis (−12.4° vs −5.7°, p = 0.037). A change in cervical lordosis correlated with changes in T-1 slope (r = −0.621, p <0.001), C7–T12 inclination (r = 0.418, p <0.001), T12–S1 angle (r = −0.339, p = 0.005), and C7–S1 plumb line (r = 0.289, p = 0.018). Radiographic parameters that correlated with changes in cervical lordosis on multivariate linear regression analysis included change in T-1 slope and change in C2–7 plumb line (r2 = 0.53, p <0.001).


Adults with positive sagittal spinopelvic malalignment compensate with abnormally increased cervical lordosis in an effort to maintain horizontal gaze. Surgical correction of sagittal malalignment results in improvement of the abnormal cervical hyperlordosis through reciprocal changes.

Abbreviations used in this paper:ASD = adult spinal deformity; ISSG = International Spine Study Group; LL = lumbar lordosis; PI = pelvic incidence; PSO = pedicle subtraction osteotomy; PT = pelvic tilt; SS = sacral slope; SVA = sagittal vertical alignment; TK = thoracic kyphosis.

Article Information

Address correspondence to: Christopher P. Ames, M.D., Department of Neurosurgery, University of California, San Francisco, 400 Parnassus Avenue, A850, San Francisco, California 94143-0112. email: amesc@neurosurg.ucsf.edu.

Please include this information when citing this paper: published online August 3, 2012; DOI: 10.3171/2012.6.SPINE1250.

© AANS, except where prohibited by US copyright law.



  • View in gallery

    Case example. Preoperative (A and B) and postoperative (C and D) sagittal radiographs showing measurement markup. Note the decrease in cervical lordosis following lumbar PSO. CL = cervical lordosis; PL = plumb line.

  • View in gallery

    Diagrammatic demonstration of the changes in sagittal spinopelvic alignment that occur after lumbar PSO. Left: Depiction of significant positive sagittal malalignment, increased cervical lordosis to maintain horizontal gaze, and a lumbar wedge symbolizing the bone removal for a lumbar PSO. Right: Depiction of corrected sagittal alignment and decrease of cervical lordosis following closure of a lumbar PSO. Printed with permission from Kenneth Xavier Probst.



Blondel BSchwab FAmes CPLeHuec JCSmith JSDemakakos J: The crucial role of cervical alignment in regulating sagittal spino-pelvic alignment in human standing posture. Presented at the 19th International Meeting on Advanced Spine TechniquesIstanbul TurkeyJuly 18–212012


Bridwell KH: Decision making regarding Smith-Petersen vs. pedicle subtraction osteotomy vs vertebral column resection for spinal deformity. Spine (Phila Pa 1976) 31:S171S1782006


Bridwell KHLewis SJLenke LGBaldus CBlanke K: Pedicle subtraction osteotomy for the treatment of fixed sagittal imbalance. J Bone Joint Surg Am 85-A:4544632003


Bridwell KHLewis SJRinella ALenke LGBaldus CBlanke K: Pedicle subtraction osteotomy for the treatment of fixed sagittal imbalance. Surgical technique. J Bone Joint Surg Am 86-A:Suppl 144502004


Canavese FTurcot KDe Rosa Vde Coulon GKaelin A: Cervical spine sagittal alignment variations following posterior spinal fusion and instrumentation for adolescent idiopathic scoliosis. Eur Spine J 20:114111482011


Champain SBenchikh KNogier AMazel CGuise JDSkalli W: Validation of new clinical quantitative analysis software applicable in spine orthopaedic studies. Eur Spine J 15:9829912006


Cho KJBridwell KHLenke LGBerra ABaldus C: Comparison of Smith-Petersen versus pedicle subtraction osteotomy for the correction of fixed sagittal imbalance. Spine (Phila Pa 1976) 30:203020382005


Glassman SDBerven SBridwell KHorton WDimar JR: Correlation of radiographic parameters and clinical symptoms in adult scoliosis. Spine (Phila Pa 1976) 30:6826882005


Gore DRSepic SBGardner GM: Roentgenographic findings of the cervical spine in asymptomatic people. Spine (Phila Pa 1976) 11:5215241986


Gore DRSepic SBGardner GMMurray MP: Neck pain: a long-term follow-up of 205 patients. Spine (Phila Pa 1976) 12:151987


Grob DFrauenfelder HMannion AF: The association between cervical spine curvature and neck pain. Eur Spine J 16:6696782007


Guo QNi BYang JLiu KSun ZZhou F: Relation between alignments of upper and subaxial cervical spine: a radiological study. Arch Orthop Trauma Surg 131:8578622011


Gwinn DEIannotti CABenzel ECSteinmetz MP: Effective lordosis: analysis of sagittal spinal canal alignment in cervical spondylotic myelopathy. Clinical article. J Neurosurg Spine 11:6676722009


Hardacker JWShuford RFCapicotto PNPryor PW: Radiographic standing cervical segmental alignment in adult volunteers without neck symptoms. Spine (Phila Pa 1976) 22:147214801997


Klineberg ESchwab FJAmes CPHostin RBess SSmith JS: Acute reciprocal changes distant from the site of spinal osteotomies affect global postoperative alignment. Adv Orthop 21:6987042012


Knott PTMardjetko SMTechy F: The use of the T1 sagittal angle in predicting overall sagittal balance of the spine. Spine J 10:9949982010


Kuntz C IVLevin LSOndra SLShaffrey CIMorgan CJ: Neutral upright sagittal spinal alignment from the occiput to the pelvis in asymptomatic adults: a review and resynthesis of the literature. J Neurosurg Spine 6:1041122007


Lafage VAmes CSchwab FKlineberg EAkbarnia BSmith J: Changes in thoracic kyphosis negatively impact sagittal alignment following lumbar pedicle subtraction osteotomy. Spine (Phila Pa 1976) 37:E180E1872012


Lafage VBharucha NJSchwab FHart RABurton DBoachie-Adjei O: Multicenter validation of a formula predicting postoperative spinopelvic alignment. Clinical article. J Neurosurg Spine 16:15212012


Lafage VSchwab FPatel AHawkinson NFarcy JP: Pelvic tilt and truncal inclination: two key radiographic parameters in the setting of adults with spinal deformity. Spine (Phila Pa 1976) 34:E599E6062009


Lafage VSchwab FSkalli WHawkinson NGagey PMOndra S: Standing balance and sagittal plane spinal deformity: analysis of spinopelvic and gravity line parameters. Spine (Phila Pa 1976) 33:157215782008


Lafage VSchwab FVira SHart RBurton DSmith JS: Does vertebral level of pedicle subtraction osteotomy correlate with degree of spinopelvic parameter correction? Clinical article. J Neurosurg Spine 14:1841912011


Lafage VSchwab FVira SPatel AUngar BFarcy JP: Spino-pelvic parameters after surgery can be predicted: a preliminary formula and validation of standing alignment. Spine (Phila Pa 1976) 36:103710452011


Lafage VSmith JSBess SSchwab FAmes CPKlineberg E: Sagittal spino-pelvic alignment failures following three column thoracic osteotomy for adult spinal deformity. Eur Spine J 21:2987942012


Nojiri KMatsumoto MChiba KMaruiwa HNakamura MNishizawa T: Relationship between alignment of upper and lower cervical spine in asymptomatic individuals. J Neurosurg 99:1 Suppl80832003


Rillardon LLevassor NGuigui PWodecki PCardinne LTemplier A: [Validation of a tool to measure pelvic and spinal parameters of sagittal balance.]. Rev Chir Orthop Repar Appar Mot 89:2182272003. (Fr)


Rose PSBridwell KHLenke LGCronen GAMulconrey DSBuchowski JM: Role of pelvic incidence, thoracic kyphosis, and patient factors on sagittal plane correction following pedicle subtraction osteotomy. Spine (Phila Pa 1976) 34:7857912009


Schwab FFarcy JPBridwell KBerven SGlassman SHarrast J: A clinical impact classification of scoliosis in the adult. Spine (Phila Pa 1976) 31:210921142006


Schwab FLafage VBoyce RSkalli WFarcy JP: Gravity line analysis in adult volunteers: age-related correlation with spinal parameters, pelvic parameters, and foot position. Spine (Phila Pa 1976) 31:E959E9672006


Schwab FLafage VPatel AFarcy JP: Sagittal plane considerations and the pelvis in the adult patient. Spine (Phila Pa 1976) 34:182818332009


Schwab FPatel AUngar BFarcy JPLafage V: Adult spinal deformity-postoperative standing imbalance: how much can you tolerate? An overview of key parameters in assessing alignment and planning corrective surgery. Spine (Phila Pa 1976) 35:222422312010


Schwab FUngar BBlondel BBuchowski JCoe JDeinlein D: Scoliosis Research Society–Schwab adult spinal deformity classification: a validation study. Spine (Phila Pa 1976) 37:107710822012


Sherekar SKYadav YRBasoor ASBaghel AAdam N: Clinical implications of alignment of upper and lower cervical spine. Neurol India 54:2642672006


Tang JAScheer JKSmith JSDeviren VBess SHart RA: Positive cervical sagittal alignment negatively impacts outcomes following adult posteruior cervical fusion procedures. Neurosurgery [epub ahead of print]2011


Villavicencio ATBabuska JMAshton ABusch ERoeca CNelson EL: Prospective, randomized, double-blind clinical study evaluating the correlation of clinical outcomes and cervical sagittal alignment. Neurosurgery 68:130913162011




All Time Past Year Past 30 Days
Abstract Views 79 79 26
Full Text Views 79 79 13
PDF Downloads 149 149 19
EPUB Downloads 0 0 0


Google Scholar