Cong scoliosis

Congenital ScoliosisA Review and Update

Daniel Hedequist, MD and John Emans, MD

Abstract: Vertebral anomalies causing congenital scoliosis are

classified on the basis of failures of formation, segmentation, or both.

The natural history depends on the type of anomaly and the location

of anomaly. Patient evaluation focuses on the history and physical

examination, followed by appropriate imaging modalities. The

hallmark of surgical treatment is early intervention before the

development of large curvatures. The surgical treatment of a

congenital deformity mandates the use of neurological monitoring to

minimize the risk of perioperative neurological deficit. Modern

surgical techniques have evolved to include the routine use of spinal

instrumentation. Patients with associated chest wall deformities or

large compensatory curves may be candidates for vertical expansion

prosthetic titanium rib placement or growing rods insertion to

maximize growth.

Key Words: congenital scoliosis, surgical treatment, VEPTR

(J Pediatr Orthop 2007;27:106Y116)

The prevalence rate of congenital scoliosis is thought to beapproximately 1 in 1000 live births.1,2 There is currently

no known cause for the development of a congenital vertebralanomaly. Strong evidence based on basic science research inmice suggests that maternal exposure to toxins, such ascarbon monoxide exposure, may cause congenital scolio-sis.3,4 Associations with maternal diabetes and ingestion ofantiepileptic drugs during pregnancy have also been postu-lated as possible causes.5,6 Genetic inheritance has beenshown responsible for some congenital vertebral anomalies;however, there is no clear-cut genetic etiology of congenitalscoliosis to date.2,7,8 Although fetal imaging modalities, suchas magnetic resonance imaging (MRI) and ultrasound, haveimproved our ability to diagnose vertebral anomalies in utero,they do not have any therapeutic role in the clinicalsetting.9,10 The goal of treatment of congenital scoliosis isearly diagnosis and treatment, if indicated. Modern imagingmodalities have improved our diagnostic capabilities and ourability to screen for spinal dysraphism.11,12 Surgical treat-ment revolves around early arthrodesis for progressivedeformities and has evolved to include the routine use ofspinal instrumentation. Patients with congenital rib fusions in

concert with congenital scoliosis are at risk of severerestrictive lung disease and of thoracic insufficiency.13

Expansion thoracoplasty and placement of vertical expansionprosthetic titanium rib (VEPTR) devices have evolved into atreatment option for children with the most difficult problems.The purpose of this article is to serve as a review and updateof congenital scoliosis.

CLASSIFICATIONVertebral anomalies causing congenital scoliosis may

be caused by a failure of formation, by failure of segmenta-tion, or by a combination of these 2 factors, resulting in amixed deformity.14 An incomplete failure of formation leadsto a wedge vertebra (Fig. 1). A wedge vertebra has asymmetryin height, with 1 side being hypoplastic; however, there arebilateral pedicles. Complete failure of formation results in ahemivertebra, with the absence of 1 pedicle and a region ofvertebral body. Hemivertebra may be further classified on thebasis of the presence or the absence of fusion to the vertebralbodies above and/or below.15 An unsegmented hemivertebrais fused to the vertebral body above and below; a partiallysegmented hemivertebra is fused to the vertebral body eitherabove or below; and a fully segmented hemivertebra isseparated from the body above and below by disk space.Hemivertebra may occur at ipsilateral adjacent levels of thespine, which produces significantly asymmetrical spinegrowth, or a hemivertebra may be counterbalanced by ahemivertebra on the contralateral side of the spine in the sameregion, separated by 1 or several healthy vertebrae (this istermed a hemimetameric shift).16

The defects of segmentation are characterized byabnormal bony connections between vertebrae (Fig. 2).These bony connections may be bilateral and symmetrical,resulting in a block vertebra. Segmentation defects caused byunilateral bony fusions are termed bars and may act as aunilateral growth tether. Occasionally, a segmentation defectmay span an ipsilateral formation defect, resulting in aunilateral bar and a contralateral hemivertebra.17

Mixed deformities are common and may be difficult todefine, given the abnormal anatomy and the resultant occa-sionally severe deformity.18 Scoliosis caused by multiplevertebral anomalies may also be associated with rib abnorm-alities; this may be associated with severe stunting of thoracicvolume and a restriction of pulmonary function.13,19

NATURAL HISTORYThe progression of congenital scoliosis depends on both

the type and the location of the vertebral anomaly.18 Curveprogression is caused by unbalanced growth of 1 side of the

CURRENT ISSUES

106 J Pediatr Orthop & Volume 27, Number 1, January/February 2007

From the Childrens Hospital Boston, Harvard Medical School, Boston, MA.The authors state that they no proprietary interest in the products named in

this article.Reprints: Daniel Hedequist, MD, Childrens Hospital Boston, 300 Longwood

Ave, Department of Orthopedics, Hunnewell 2, Boston, MA 02114. E-mail:[email protected].

Copyright * 2007 by Lippincott Williams & Wilkins

Copyr ight © Lippincott Williams & Wilkins. Unauthorized reproduction of this article is prohibited.

spine relative to the other. Radiographically, definable diskssignify the presence of vertebral growth plates and, whenasymmetrical or more present on 1 side of the spine than onthe other, have potential for asymmetrical growth in that areaof the spine. Thus, fully segmented hemivertebra withhealthy, definable disks above and below have much morepotential to cause curvature compared with an unsegmentedhemivertebra, which is fused to the vertebra above andbelow.15 Likewise, the asymmetrical tethering of the spineleads to curvature with growth, as is seen with bars or ribfusions on the concavity of a curve.

The rate of curve progression depends on the type ofanomaly, the age of the patient, and the location of the curve(Fig. 3). Curve progression occurs more rapidly during thefirst 5 years of life and, again, during the adolescent growthperiod of puberty; these 2 periods represent the most rapidstages of spine growth.20 Anomalies at the cervicothoracicand lumbosacral junctions produce more visible deformities

than those seen at other areas of the spine. The anomaly mostprobable to produce the most severe scoliosis is the unilateralbar with contralateral hemivertebra, followed by a unilateralbar, a hemivertebra, a wedge vertebra, and, finally, the mostbenign of all anomaliesVthe block vertebra.18 Mixeddeformities are unpredictable, and their severity depends onthe amount of unbalanced growth potential.

PATIENT EVALUATIONThe evaluation of a patient with congenital scoliosis

focuses on the physical examination, the search for otheranomalies, and radiographic evaluation. The physical exam-ination should start with the height and the weight of thepatient, given that growth plays a significant role in curveprogression. The skin needs to be evaluated for any evidenceof spinal dysraphism, such as abnormal pigmentation, hairypatches, or skin tags over the cutaneous region of the spine.Spinal dysraphism may also manifest itself in the lowerextremities, and signs would include asymmetrical calves,cavus feet, clubfeet, vertical tali, and abnormal neurologicalfindings. The spinal examination itself focuses on anyevidence of truncal or pelvic imbalance. Rib cage deformitiesand anomalies need to be evaluated, as does the inspiratoryand expiratory capacity of the chest wall, given the possibilityof any associated restrictive lung disease. Spinal balance inboth the coronal and the sagittal planes needs to be evaluated.Truncal imbalance, head tilt, shoulder inequality, and pelvic

FIGURE 1. Schematic representation of formation failures. A,Wedge vertebra. B, Fully segmented hemivertebra. C, Partiallysegmented hemivertebra. D, Unsegmented hemivertebra.Reproduced with permission from Hedequist and Emans.14

FIGURE 2. Schematic representations of failures ofsegmentation. A, Block vertebra. B, Bar. C, Bar withcontralateral hemivertebra. Reproduced with permissionfrom Hedequist and Emans.14

FIGURE 3. Radiograph, taken from an adolescent patient,of an untreated lumbar hemivertebra causing progressivedeformity.

J Pediatr Orthop & Volume 27, Number 1, January/February 2007 Congenital Scoliosis: A Review and Update

* 2007 Lippincott Williams & Wilkins 107


balance all need to be addressed and recorded. Given theassociation of neural axis abnormalities and the possibility ofneurological compromise in congenital spine deformities, athorough neurological examination of strength, sensation, andreflexes, including abdominal reflexes, becomes mandatory.

ASSOCIATED ANOMALIESNeural axis abnormalities are present in up to 35% of

patients, as detected with MRI.21 These abnormalities include(but are not limited to) diastematomyelia (split cord), cordtethering, Chiari malformations, and intradural lipomas. Theabsence of cutaneous signs of dysraphism and the absence ofneurological deficit do not rule out an intraspinal dysraphism.

Congenital heart disease is observed in up to 25% ofpatients with congenital scoliosis.22 The abnormalities maybe benign and may be detected during a routine preoperativeappointment; however, they may be severe, and the child mayhave an already extensive cardiac history. The cardiac defectsrange from atrial and ventricular septal defects, which are themost common abnormalities, to complex congenital heartdefects, such as tetralogy of Fallot and transposition of thegreat vessels. Patients who are undergoing an operation for acongenital spine deformity need a screening echocardiogram,with referral to a cardiologist if indicated.

Genitourinary anomalies are observed in up to 20% ofpatients with congenital scoliosis.22 The abnormalities maybe asymptomatic and may be detected on a routine screeningtest, or they may be significant enough to have already beendiagnosed and have required treatment. Anomalies mayaffect the kidneys, ureters, bladder, or urethra. These includehorseshoe kidney, renal aplasia, duplicate ureters, andhypospadias. A renal ultrasound remains to be the criterionstandard for urological screening in these patients, and anabnormal ultrasound result demands a referral to a urologist.

Musculoskeletal anomalies occur frequently in associa-tion with congenital spine anomalies. Disorders, such asclubfeet, Sprengel deformity, Klippel-Feil deformity, devel-opmental dysplasia of the hip, and upper and lower limbdeformities, need to be evaluated and treated appropriately ifpresent in these patients.

IMAGINGPlain radiographs remain a reliable standard for

diagnosis of congenital anomalies and for following curveprogression.23 The details of vertebral anomalies may beparticularly evident on plain x-ray results of the infant. Theadvent of computed tomography (CT) and MRI haveimproved our ability to study spinal anatomy and to screenfor spinal dysraphism.11,21,24

We routinely use CT with 3-dimensional reconstruc-tions for preoperative assessment and evaluation of complexdeformities, but not for routine observation or serialdocumentation11 (Fig. 4). Concern exists regarding thesignificant radiation exposure during CT examination.25,26

Tube current (in milliamperes), kilovoltage, and, particularly,slice thickness all contribute to the amount of radiation that apatient receives in the CT scanner.11,25 Most probably,institutions do have written protocols in place to minimize the

radiation that children receive during CT examination, andsurgeons should urge that these protocols be used. The abilityto create 3-dimensional images is software based and does notrequire additional radiation exposure. Hedequist andEmans,11 in a retrospective study comparing the findings atoperation compared with the findings seen on preoperativeradiographs and CT scans, concluded that CT scans were100% accurate in defining the anatomy and the unrecognizedanomalies not seen on plain films. Newton et al27 found thatin 17 of 31 patients with congenital spine deformities, CTscanning with image reformatting allowed for the identifica-tion of unrecognized malformations not seen on plain filmsalone. Preoperative CT scans help in clearly defining theanatomy and avoid any unexpected encounters with posteriorelement deficiencies at the time of surgical intervention.

Computed tomography scans that include the chest andribs are useful for the evaluation of chest wall deformity andlung volume in congenital deformities with chest wall anoma-lies, chest deformity, or thoracic insufficiency. Smith et al61

were able to use 3-dimensional CT data to define lung volumesin patients who were too young for pulmonary function tests;subsequently, they were able to use this data as a measure ofimprovement in lung function after expansion thoracoplasty.Others have used this tool to measure improvements in chestwall, lung volume, and spinal growth measurements afterexpansion thoracoplasty.29,30

Magnetic resonance imaging has replaced myelogramas the procedure of choice in detecting occult spinaldysraphism. The efficacy of MRI has been widely studiedand documented in patients with congenital scoliosis.12,21

The prevalence rate of spinal dysraphism detected using MRIapproaches 30% in patients with congenital spine deformi-ties. We do not routinely instruct to perform an MRI on allpatients with congenital spine deformities; however, patients

FIGURE 4. Three-dimensional CT scan showing the anatomicaldetail of a lumbar partially segmented hemivertebra.

Hedequist and Emans J Pediatr Orthop & Volume 27, Number 1, January/February 2007

108 * 2007 Lippincott Williams & Wilkins


with progressive deformities, major extremity anomalies,abnormal reflexes, or neurological deficits are best evaluatedwith a spinal MRI. We have also found magnetic resonanceimaging helpful in documenting any canal stenosis or cordimpingement in patients with kyphoscoliosis, both as apreoperative and a postoperative measure to determine theefficacy of decompression (Fig. 5).

Patients undergoing operative treatment of their spinaldeformity may benefit from specialized radiographs beforesurgery to determine the flexibility of the spine. Theseradiographs include traction views, push-prone views, supinebending films, and films over a bolster. These curves helpdetermine flexibility and help determine the stable vertebrafor instrumentation.

SURGICAL PRINCIPLESSurgical treatment of patients with congenital spinal

deformities carry a risk of neurological injury greater thanthat of patients with idiopathic spinal deformity.31 Theoccurrence of a perioperative neurological deficit may beminimized in multiple ways, the first being the routine use ofMRI evaluation of the spinal cord. The risk of neurologicalinjury from surgical manipulation of a congenital spinedeformity with an associated spinal cord anomaly may bereduced by earlier treatment of the spinal cord anomaly.Occasionally, neurosurgical treatment may be performed at

the same time as the deformity surgery; however, thisdepends on the magnitude of each procedure and the opinionof the neurosurgeon.32

Early and aggressive treatment of deformities beforethey become severe helps in minimizing the risk to thepatient. The avoidance of lengthening the spinal cordintraoperatively by avoiding intraoperative distraction andby using shortening procedures during surgery also mini-mizes the chance of a perioperative neurological deficit. Theuse of controlled hypotension to minimize blood loss shouldbe monitored carefully to minimize the occurrence ofunwanted cord ischemia, especially during any correctivemaneuvers.

Motor- and sensory-evoked potential monitoring issuggested whenever possible for any surgical case. There isan increased risk of a perioperative neurological injury whenbaseline monitoring cannot be established.33 The intraopera-tive changes in neurological monitoring that do not return tobaseline may be investigated further by performing a wake-up test.34,35 At our institution, we also perform a wake-up testat the end of each deformity case to minimize any chance of aneurological deficit. The ability to perform wake-up testseven on younger patients has been shown effective.36 Thepostoperative monitoring of a patient`s neurological statusalso remains paramount, given that paraplegia after deformitysurgery may present in a delayed fashion, especially in thefirst 72 hours.35,37

SPINAL INSTRUMENTATIONThe use of spinal instrumentation for congenital spine

deformities has evolved since the description by Hall et al38 in1981. Newer, downsized implants are available, whereastitanium implants have allowed for increased MRI compat-ibility. Hedequist et al39 studied the use of downsizedinstrumentation in patients with congenital spine deformities.In that series, the average patient was aged 3.3 years, with apreoperative Cobb measurement of 41 degrees; all patientswere treated with an instrumented fusion. There were noneurological complications; the implant maintained correc-tion in the coronal plane and, at follow-up after more than2 years, there were no pseudarthroses. They concludedthat instrumentation was safe and effective in congenitalscoliosis even in the youngest of patients. This data wasfurther elucidated in a study of 103 patients with congenitalspine deformities treated with instrumentation at an ageyounger than 18 years. In this series, the pseudarthrosisrate and the curve correction were similar to those in thepreviously described series, with no reported neurologicalabnormalities.40

The efficacy of instrumentation in congenital deformitysurgery was supported by Ruf and Harms41 who studiednewer generation implants in younger patients during poste-rior-only hemivertebra resection. They found that instrumen-tation could be safely used in this population. They furtherstudied spinal implants in younger patients by looking at theefficacy of pedicle screws in patients younger than 2 years.42

Screw insertion was safe and feasible in 1-year-old patients;in addition, they found no instances of canal stenosisassociated with instrumentation crossing the neurocentral

FIGURE 5. A, Preoperative MRI scan taken from a patient withcongenital kyphoscoliosis causing cord compression (arrow)and myelopathy. B, Postoperative MRI scan showing thedecompression of the spinal cord after partial apicalvertebral resection (arrow).




synchondrosis. Kim et al,43 in a study of patients withcongenital kyphosis, found that the use of spinal implantsincreased union rate and maintained curve correction bet-ter than in the case of uninstrumented patients. Thus, werecommend that newer, downsized implants be safely usedin patients with congenital spine deformities. We alsorecommend that implants, if at all possible, should betitanium, given the increased use of MRI for monitoring notonly spinal dysraphism but also cardiac disease andgenitourinary anomalies.44

FUSION IN SITUIn situ fusion is a safe technique and a good choice for

many progressive curves with minimal deformity involving arelatively short section of the spine.45 Prophylactic in situfusion may be justified for fully segmented hemivertebra,given that the rates of progression for these deformities areextremely high.15 In situ arthrodesis over a short segment ofthe spine for these types of deformity is associated with onlylimited loss in spinal height and good long-term results, evenwhen performed in younger children.46 Successful arthrod-esis is based on thorough facet resection, decortication, andplacement of abundant bone graft. The use of spinalinstrumentation has been shown safe and efficacious inyounger children with congenital scoliosis, probablyincreases the fusion rate, and may diminish the time neededin a brace or a cast.39 Given the paucity of graft availablefrom the iliac crest in smaller children, allograft is anattractive alternative and has been shown effective inobtaining fusion.40

The need for an anterior fusion with disk excision and aposterior in situ fusion and arthrodesis depends on the growthpotential of disks viewed anteriorly, the amount of growthremaining, and the magnitude and direction of curvature. Thedisk quality and, by inference, the growth potential of theadjacent vertebral endplates may be evaluated using plainradiographs and preoperative MRI and CT scans. Althoughthe disk spaces are frequently small remnants, the failure toperform an anterior procedure in the face of healthy disksmay lead to the crankshaft phenomena, with progression ofcurvature in the face of a solid posterior arthrodesis.47,48 Inlordotic deformities, anterior-only in situ fusion may bepreferable and sufficient to arrest progression. Kyphoticdeformities may profit most from posterior-only fusion, withanticipated anterior growth and slow deformity improvementoccurring relative to a posteriorly created tether. The anteriorprocedure may be performed either through an anterior, opentechnique, thoracoscopically, or through a posterior approachvia the pedicles, depending on the location of the anomalyand the preference of the surgeon.49,50

CONVEX HEMIEPIPHYSIODESISConvex hemiepiphysiodesis, as the name implies, is a

partial growth arrest procedure. For this procedure to beeffective, little or no concave growth potential. Thus, failuresof segmentation with no little or no growth potential cannotbe successfully treated this way. The most commonindication is a unilateral failure of formation, a hemivertebra.Much of the correction associated with this procedure is

achieved acutely at the time of the initial procedure using acorrective postoperative cast. The total correction obtained byperforming a convex hemiepiphysiodesis varies because theyounger the child at the time of the operation, the morepotential that exists for correction over time. In general, thisprocedure should be reserved for patients younger than 5 yearswho have modest deformity, given that the long-term resultsyield less than 15 degrees of total correction, with somepatients obtaining no correction.51 Possibly more predictablealternatives to convex hemiepiphysiodesis include hemiver-tebra resection or wedge resection, when the deformityinvolves a short segment of spine, and growth-oriented proce-dures, such as VEPTR placement or growing rods insertion,when a longer segment of spine is involved.

HEMIVERTEBRA EXCISIONHemivertebra excision remains a safe and effective tool

for treating an isolated hemivertebra that produces curveprogression and causes truncal imbalance. The options of insitu fusion and convex epiphysiodesis have been shownreliable at obtaining a growth arrest and stopping curveprogression; however, they afford no correction of deformityand truncal imbalance.51,52 The optimal indication forhemivertebra resection remains the same: a patient youngerthan 5 years with a thoracolumbar, lumbar, or lumbosacralhemivertebra and associated truncal imbalance. The surgicaltechnique of hemivertebra excision varies from stagedanterior and posterior procedures to isolated posteriorwedge resections, with the decision based on the experienceand preference of the surgeon.53,54

The excision of a hemivertebra may be performed byusing combined anterior and posterior procedures. Thistechnique allows for the circumferential exposure of thespine, with the ability to obtain a complete excision of thedisks above and below the hemivertebra. Anterior andposterior exposure of the spine may be performed assequential procedures under a single anesthetic. Althoughthis affords excellent visualization, the operative time tendsto be longer, given the magnitude of the surgery and the needto reposition and drape the patient.55 Anterior and posteriorexposure has been shown effective for hemivertebra excisionwhen performed as simultaneous procedures. Hedequist etal56 reported on their series of 18 patients treated by means ofsimultaneous exposures with excision and instrumentation.The average age of the patients was 3 years, with an averagecurve correction of 70%. There were no neurologicalcomplications, and all patients obtained fusion from theindex operation.

Posterior-only hemivertebra excision in growing chil-dren has recently been reported with successful results.54,57

We have found the ideal indication to be the hemivertebralocated at the thoracolumbar junction or in the lumbar spine,with some associated kyphosis. Ruf and Harms54 reportedtheir results on hemivertebra excision using posterior-onlyapproach and segmental transpedicular instrumentation. Theyreported excellent results in patients younger than 6 years,with an average Cobb measurement of 45 degrees. At 3.5 yearsfollow-up, the Cobb measurement had been maintained at14 degrees, with no patient having a neurological complication.




Shono et al58 reported on their experience involving 12 pa-tients treated with hemivertebra excision and segmentalinstrumentation during adolescence. Their correction rate was64%, with all patients obtaining fusion and no patient havinga neurological deficit. The posterior resection of hemivertebrais a demanding procedure that may be performed safely byexperienced hands with good correction rate and minimalneurological risk.

CORRECTION AND FUSION WITHINSTRUMENTATION

Partial or complete correction of a congenital spinedeformity may be possible by means of arthrodesis andinstrumentation. The partial or complete correction of adeformity is based on the congenital anomaly itself, thedegree of deformity, and the magnitude of surgery. The stablezones of operation may be defined by the standing spinalradiographs, with additional information regarding theflexibility of the anomaly and the adjacent spine deemed bybending x-rays or traction x-rays.

Congenital anomalies associated with relatively normalsegmentation, flexibility (as revealed by radiographs), andless severe truncal deformity may be managed by means ofstandard posterior arthrodesis and instrumentation. The useof modern neurological monitoring techniques and goodsurgical technique allows this to be a relatively safe surgicaloption for mild to moderate deformities.39,40 The addition ofanterior surgery in these cases may be done in 2 situations(1) The patient has well-defined disk spaces seen on imaging

studies and has significant remaining growth; this patientmay be at risk of crankshaft and should have either an openor a thoracoscopic anterior release and fusion.47 (2) Thepatient has a moderately sized deformity, has well-defineddisks on imaging studies, and has less flexibility as revealedby bending radiographs. An anterior procedure withdiscectomies and bone grafting performed in these patientsaids in obtaining a well-balanced spine and aids in helpingobtain fusion.

The correction of more severe deformities may besignificantly more challenging with a greater prevalence ofneurological compromise. Osteotomies of vertebral congeni-tal fusions and bars may aid in correction but are also fraughtwith more risks associated with either direct or indirect cordinjury and significant intraoperative hemorrhage.57,59 Thesurgery for these deformities may be either combined anteriorand posterior procedures or posterior-only procedures withinstrumentation (Fig. 6). Anterior surgery for more severedeformities should be performed as an open procedure, withdiscectomies and osteotomies at a single level or multiplelevels being performed, depending on the degree ofdeformity. The addition of anterior surgery to a posteriorprocedure may be conducted at the same anesthetic or as aseparate procedure, depending on the magnitude of surgery.

Posterior-only procedures, such as pedicle subtractionosteotomies or vertebral column resection, offer correction ofsevere deformities without a separate anterior surgicalapproach. These procedures are technically demanding andare associated with significant blood loss and neurologicalrisk. The use of pedicle subtraction techniques as used in

FIGURE 6. A, Plain radiograph depicting significant coronal imbalance in a patient with multiple congenital anomalies(arrows). B and C, Postoperative radiographs depicting coronal and sagittal balance after anteroposterior surgery with osteotomiesand instrumentation.




adults for kyphotic deformity may be beneficial.57,59 Thedisadvantages of posterior-only procedures include thedifficulty with anterior column visualization during anyperiod of significant blood loss, the need for spinal cord anddural manipulation, and the potential for perioperativedisplacement at the osteotomy site. Planning of circumfer-ential osteotomies should be conducted preoperatively byusing 3-dimensional CT to understand the deformity and toanticipate the anomalous anatomy. As with any procedurebeing performed on the spine, the planned osteotomy shouldbe one that shortens the spinal column and relies oncompression rather than on distraction and lengthening.

Anterior access to the spinal column may be mostreadily managed by using a posterior approach when there isan associated kyphosis or extreme degrees of rotation.57,59Y61

A patient with congenital kyphosis or congenital kyphosco-liosis may require circumferential treatment for curvecorrection and/or decompression. Given the kyphotic natureof some deformities and the posterior positioning of the apex,an anterior surgery may be technically unfeasible, given thedifficulty of access in a thoracotomy (Fig. 7). Access to theanterior column may be provided through a costotransverse-ctomy, which allows access to the anterior portion of thespine through a posterior incision. Smith et al61 reported on a

series of 16 patients treated in this manner for congenitalkyphosis. Vertebral resection or osteotomies were performedusing a costotransversectomy approach, with satisfactoryresults in 13 of 16 patients. In their series, the mean kyphosiswas corrected from 65 to 34 degrees, and instrumentation wasused in all but 1 patient. The authors concluded that forcomplex kyphotic deformities of the thoracic spine, costo-transversectomy should be considered.

TRACTIONCongenital spine deformities occasionally present as

rigid, severe curves, which may be impossible to correctusing standard instrumentation techniques. The safety oftraction in congenital spine deformities, particularly in casesinvolving preexisting neurological deficits, has been ques-tioned in the past reports by MacEwen et al31 with regard tothe risk of traction-induced paraplegia in congenital defor-mities. Recently, the use of traction has been popularized forsevere deformities, including congenital deformities.62,63 Theuse of halo gravity traction has been reported on by Sinket al62 and then expanded on by Rinella et al63; both series hadno permanent neurological deficits. Halo gravity tractionallows patients to have gradual weight applied to the halo ringeither while in bed or while in a wheelchair or walker device.Weight is applied daily until partial curve correction isattained; any evidence of neurological demise calls fordecreasing the traction weight. This technique allows forsome gradual curve correction before an operation. It may beused before or after an associated anterior release.

Halo-femoral traction has recently been described byMehlman et al.64 They used this method of traction after anassociated spinal release and described the technique theyused on 24 patients, with an average pretraction radiograph of95 degrees and a posttraction radiograph of 44 degrees. Thepatients were maintained in traction at an average of 54% ofbody weight. The final curve correction was 71% with nopermanent neurological deficits.

FUSIONLESS SURGERYPatients younger than 5 years who have congenital

deformities involving long sections of the spine or with largecompensatory curves in normally segmented regions present agreat challenge for treatment. In the past, the early arthrodesisof the spine was thought to be beneficial and to have atolerable effect on sitting and trunk height.46 However, recentstudies have shown that early arthrodesis over a section of thethoracic spine before the age of 5 years may be associated witha significant reduction in pulmonary function.65

The growth of the spine is greatest during the first5 years of life as sitting height reaches two thirds of the adultlevel by age 5, whereas the thorax has achieved less of its adultvolume. Congenital scoliosis is associated with short statureand diminished trunk height. Long fusions performed onyounger children may have a further deleterious effect ontrunk height and thoracic volume, leading to thoracicinsufficiency. In the absence of congenital rib fusions, treatingpatients with early progressive deformities may best beconducted by using a growing rod technique.

FIGURE 7. Preoperative 3-dimensional CT scan, taken from apatient with congenital kyphoscoliosis, depicting the potentialdifficulty in obtaining apical access through an anteriorapproach. This patient was treated with a decompressionprocedure via costotransversectomy and fusion with spinalinstrumentation.




Surgically, the treatment of deformity by way ofinstrumentation without fusion was first pioneered by PaulHarrington66 in the 1960s. His experiences led him to believethat a definitive fusion should not be performed before age 10and that instrumentation without fusion should be consideredin younger patients. Moe et al67 then reported their techniqueof limited exposure in the placement of implants, withresultant growth seen in the instrumented areas of the spine.Several authors have continued to study this technique and,recently, Blakemore et al68 reported on the technique theyused on a heterogeneous group of patients with newergeneration implants. They reported improvement on Cobbangles and sagittal contouring in the patients, although thefinal growth measurements were not reported.

The problems associated with a single-rod implant,including hook dislodgement and rod breakage, have ledAkbarnia et al69 to report their series of a dual growing rodconstruct. This is performed by subperiosteal dissection of theanchor sites proximally and distally and by placement of clawconstructs. Rods are then placed subcutaneously on each sideand joined with tandem connectors placed at the thoraco-lumbar junction, where the lengthening may occur. Theirpatients had an average Cobb angle improvement from 82 to38 degrees at follow-up and an average growth of the T1-S1segment of 1.2 cm per year. Thompson et al70 have reportedfurther on this technique, with encouraging results on dualrods without apical fusion. Although these reports have notbeen about homogenous groups of patients and includelimited numbers of patients with congenital scoliosis, theresults are interesting and the technique merits attention.

For patients with congenital deformities involving longregions of the spine, we have thought that this procedure is agood surgical option. At our institution, we place anchors

proximally and distally after subperiosteal dissection and addbone graft to obtain fusion at the anchor sites. Dual rods,connected to the anchor points, are placed deep to themuscular fascia to obtain partial correction, and thenlengthened every 4 to 6 months. We have found this usefulin occasional patients with congenital spine deformities.Preoperative evaluation via plain film and 3-dimensional CTscanning has been useful to determine whether the anatomywill allow for the placement of proximal and distal anchors.In general, the technique is most useful in patients who havecompensatory curves in normally segmented regions aboveand below the congenital anomalies, allowing for anchorplacement and relying on growth through more normallysegmented areas (Fig. 8).

For a patient with progressive curves that either havecongenital anomalies that will not allow for anchor placementor have associated congenital rib fusions that requirethoracostomy, we will choose expansion thoracostomy andVEPTR.

EXPANSION THORACOPLASTY AND VEPTRCongenital spine deformities with rib fusions may be

associated with a constricted thorax, leading to poor thoracicand lung parenchymal growth and to thoracic insufficiency.This term has been coined by Dr Robert Campbell to describea continuum of problems associated with spine and chestgrowth that lead to the inability to support normal lungfunction and growth.13 The tethering effect of congenital ribfusions add to the scoliotic effect of the spine to produce aconcave, constricted hemithorax, which is diminished inheight and function.19 Campbell has also described theBwindswept thorax,[ in which progressive thoracic scoliosisand rotation lead to a foreshortened hemithorax on theconcave side and a collapsed hemithorax on the convex sideof the severe scoliosis. The growth of the lung, respiratorybranches, and alveoli is greatest in the first 8 years of life.Fifty percent of the thoracic volume is obtained by age 10;thus, early fusions may have an even more profound effect onthoracic development than on spine height.20 The possibleeffect of early spinal fusion on thoracic development maycompound the preexisting thoracic insufficiency associatedwith congenital scoliosis and fused ribs.13 This interdepen-dent relationship of the spine and the chest wall has led to thedevelopment of expansion thoracoplasty and VEPTR place-ment as a possible treatment of congenital spine deformitieswith associated chest wall anomalies.71,72

The evaluation of these patients is similar to that of allpatients with congenital spine deformities; however, theyneed additional studies to document lung volumes andpulmonary function tests. Younger children are not able toreliably perform pulmonary function tests; however, theirpulmonary function can be gleamed from the data obtained by3-dimensional CT scanning.28,73 Gollogly et al28 published aseries on younger patients with thoracic insufficiency whowere being treated with expansion thoracoplasty. Theirresults indicated that measurements of lung volumes couldpredictably be performed using data obtained from the 3-dimensional reconstruction of CT scan data. These studiescould also be conducted postoperatively to quantify an

FIGURE 8. A, Preoperative radiograph taken from a 2-year-oldpatient with congenital scoliosis and rib fusions (arrows). Notethe hypoplastic right hemithorax, B, Postoperative radiographfrom the same patient after expansion thoracoplastyand VEPTR placement. Note the improvement in the volumeof the right hemithorax.




increase in the volume of lung parenchyma after expansionthoracoplasty.

Expansion thoracoplasty is a technique that involvesthe expansion of the hemithorax by osteotomizing thesegments of congenitally fused ribs or the areas of ribadhesions between anomalous sections of ribs.72 The surgicaltechnique involves a standard thoracotomy incision withdivision of the latissimus and the serratus. Once exposed, theareas on constriction may be isolated and then osteotomizedby using a rongeur and a craniotome. Once the osteotomy orlysis of adhesions is done, the area may be opened withlamina spreaders. The expansion of the chest and the ribseparation are performed by using VEPTR (Fig. 9). TheVEPTR devices can be attached spanning the ribs (rib to ribdevices) or as hybrid devices (rib to spine, rib to pelvis).Multiple devices may be used depending on the chestexpansion and the spine control needed.

Campbell et al71 have reported their results on usingthis technique in patients with congenital scoliosis and fusedribs. They found that the patients showed significantimprovement in Cobb measurement of the spine from 74 to49 degrees. The patients also had an average increase of 8 mmper year in the length of both the convex and the concavesides of the spine compared with baseline; the patients alsohad an increase in vital capacity. Most complications treatedin the series of Campbell et al were device related and readilytreatable. Emans et al29 reviewed their series on 31 patientswith thoracic insufficiency and fused ribs; they found that thegrowth of the thoracic spine after expansion was similar tothat in healthy controls. They also found that the increasedvolume of the constricted hemithorax and the total lungvolumes obtained during expansion were maintained atfollow-up. In general, we have found this treatment beneficial

to those patients with congenital scoliosis and chest walldeformities that require surgical intervention to control bothdeformities and to allow growth.

SUMMARYThe treatment of congenital scoliosis focuses on early

diagnosis and appropriate surgical management before thedevelopment of large curves. Vertebral anomalies that have anatural history of progression need to be managed aggres-sively. All patients with the diagnosis of congenital scoliosisneed a preoperative screening MRI of the spinal axis and ascreening evaluation for renal and cardiac anomalies. Thehallmark of treatment remains to be the early diagnosis beforethe development of a large curve. The surgical treatmentoptions include in situ fusion procedures and convexhemiepiphysiodesis in those cases where a progressivecurve is present in the face of minimal or no deformity.Moderate deformities may be partially corrected throughinstrumentation and arthrodesis, whereas more severedeformities may be managed by corresponding osteotomiesor vertebrectomies. Surgical correction of congenital spinaldeformity carries significant risk of neurological injury,making early, simple treatment preferable. Thoracic insuffi-ciency syndrome associated with congenital scoliosis andfused ribs is perhaps best managed during growth byexpansion thoracostomy and insertion of expandableVEPTR devices. Growing rods may be used in youngerpatients with severe curves involving long areas of normallysegmented spine. The use of neurological monitoring isparamount during any surgical procedure because the goalremains the same: to achieve a balanced spine with noresultant neurological deficit.

REFERENCES1. Shands AR Jr, Bundens WD. Congenital deformities of the spine: an

analysis of the roentgenograms of 700 children. Bull Hosp Jt Dis.1956;17:110Y133.

2. Giampietro PF, Blank RD, Raggio CL, et al. Congenital andidiopathic scoliosis: clinical and genetic aspects. Clin Med Res.2003;1:125Y136.

3. Farley FA, Hall J, Goldstein SA. Characteristics of congenital scoliosisin a mouse model. J Pediatr Orthop. 2006;26:341Y346.

4. Loder RT, Hernandez MJ, Lerner AL, et al. The induction of congenitalspinal deformities in mice by maternal carbon monoxide exposure.J Pediatr Orthop. 2000;20:662Y666.

5. Aberg A, Westbom L, Kallen B. Congenital malformations amonginfants whose mothers had gestational diabetes or preexisting diabetes.Early Hum Dev. 2001;61:85Y95.

6. Wide K, Winbladh B, Kallen B. Major malformations in infants exposedto antiepileptic drugs in utero, with emphasis on carbamazepine andvalproic acid: a nation-wide, population-based register study.Acta Paediatr. 2004;93:174Y176.

7. Erol B, Tracy MR, Dormans JP, et al. Congenital scoliosis and vertebralmalformations: characterization of segmental defects for geneticanalysis. J Pediatr Orthop. 2004;24:674Y682.

8. Maisenbacher MK, Han JS, O`Brien ML, et al. Molecular analysis ofcongenital scoliosis: a candidate gene approach. Hum Genet. 2005;116:416Y419.

9. von Koch CS, Glenn OA, Goldstein RB, et al. Fetal magnetic resonanceimaging enhances detection of spinal cord anomalies in patients withsonographically detected bony anomalies of the spine. J UltrasoundMed. 2005;24:781Y789.

10. Griffiths PD, Paley MN, Widjaja E, et al. In utero magnetic resonance

FIGURE 9. A, Radiograph taken from a 4-year-old patient witha lumbosacral hemivertebra and lumbar congenital vertebralanomalies (arrows). Note the large amount of curvaturethrough normally segmented spine. B, Postoperativeradiograph from the same patient after the insertion of bilateralgrowing rods with upper thoracic and pelvic anchors.




imaging for brain and spinal abnormalities in fetuses. BMJ. 2005;331:562Y565.

11. Hedequist DJ, Emans JB. The correlation of preoperativethree-dimensional computed tomography reconstructions with operativefindings in congenital scoliosis. Spine. 2003;28:2531Y2534.Discussion 1.

12. Belmont PJ Jr, Kuklo TR, Taylor KF, et al. Intraspinal anomaliesassociated with isolated congenital hemivertebra: the role of routinemagnetic resonance imaging. J Bone Joint Surg Am. 2004;86-A:1704Y1710.

13. Campbell RM Jr, Smith MD, Mayes TC, et al. The characteristics ofthoracic insufficiency syndrome associated with fused ribs andcongenital scoliosis. J Bone Joint Surg Am. 2003;85-A:399Y408.

14. Hedequist D, Emans J. Congenital scoliosis. J Am Acad Orthop Surg.2004;12:266Y275.

15. McMaster MJ, David CV. Hemivertebra as a cause of scoliosis. A studyof 104 patients. J Bone Joint Surg Br. 1986;68:588Y595.

16. Shawen SB, Belmont PJ Jr, Kuklo TR, et al. Hemimetameric segmentalshift: a case series and review. Spine. 2002;27:E539YE544.

17. McMaster MJ. Congenital scoliosis caused by a unilateral failure ofvertebral segmentation with contralateral hemivertebrae. Spine.1998;23:998Y1005.

18. McMaster MJ, Ohtsuka K. The natural history of congenital scoliosis. Astudy of two hundred and fifty-one patients. J Bone Joint Surg Am.1982;64:1128Y1147.

19. Tsirikos AI, McMaster MJ. Congenital anomalies of the ribs and chestwall associated with congenital deformities of the spine. J Bone JointSurg Am. 2005;87:2523Y2536.

20. Dimeglio A. Growth in pediatric orthopaedics. J Pediatr Orthop.2001;21:549Y555.

21. Prahinski JR, Polly DW Jr, McHale KA, et al. Occult intraspinalanomalies in congenital scoliosis. J Pediatr Orthop. 2000;20:59Y63.

22. Basu PS, Elsebaie H, Noordeen MH. Congenital spinal deformity: acomprehensive assessment at presentation. Spine. 2002;27:2255Y2259.

23. Facanha-Filho FA, Winter RB, Lonstein JE, et al. Measurement accuracyin congenital scoliosis. J Bone Joint Surg Am. 2001;83-A:42Y45.

24. Suh SW, Sarwark JF, Vora A, et al. Evaluating congenital spinedeformities for intraspinal anomalies with magnetic resonance imaging.J Pediatr Orthop. 2001;21:525Y531.

25. Paterson A, Frush DP, Donnelly LF. Helical CT of the body: are settingsadjusted for pediatric patients? AJR Am J Roentgenol. 2001;176:297Y301.

26. Brenner D, Elliston C, Hall E, et al. Estimated risks of radiation-inducedfatal cancer from pediatric CT. AJR Am J Roentgenol. 2001;176:289Y296.

27. Newton PO, Hahn GW, Fricka KB, et al. Utility of three-dimensional andmultiplanar reformatted computed tomography for evaluation ofpediatric congenital spine abnormalities. Spine. 2002;27:844Y850.

28. Gollogly S, Smith JT, Campbell RM. Determining lung volume withthree-dimensional reconstructions of CT scan data: a pilot study toevaluate the effects of expansion thoracoplasty on children with severespinal deformities. J Pediatr Orthop. 2004;24:323Y328.

29. Emans JB, Caubet JF, Ordonez CL, et al. The treatment of spine andchest wall deformities with fused ribs by expansion thoracostomy andinsertion of vertical expandable prosthetic titanium rib: growth ofthoracic spine and improvement of lung volumes. Spine. 2005;30:S58YS68.

30. Campbell RM Jr, Hell-Vocke AK. Growth of the thoracic spine incongenital scoliosis after expansion thoracoplasty. J Bone Joint Surg Am.2003;85-A:409Y420.

31. MacEwen GD, Bunnell WP, Sriram K. Acute neurological complicationsin the treatment of scoliosis. A report of the Scoliosis Research Society.J Bone Joint Surg Am. 1975;57:404Y408.

32. Talu U, Gogus A, Tezer M, et al. Simultaneous surgical treatment forcongenital scoliosis or kyphosis and intramedullary abnormalities [paper68]. Presented at: Scoliosis Research Society Annual Meeting;September 10Y13, 2003; Quebec City, Canada.

33. Thuet ED, Padberg AM, Raynor BL, et al. Increased risk of postoperativeneurologic deficit for spinal surgery patients with unobtainableintraoperative evoked potential data. Spine. 2005;30:2094Y2103.

34. Brustowicz RM, Hall JE. In defense of the wake-up test. Anesth Analg.1988;67:1019.

35. Mooney JF, III, Bernstein R, Hennrikus WL Jr, et al. Neurologic riskmanagement in scoliosis surgery. J Pediatr Orthop. 2002;22:683Y689.

36. Polly DW Jr, Klemme WR, Fontana JL, et al. A modified wake-up testfor use in very young children undergoing spinal surgery. J PediatrOrthop. 2000;20:64Y65.

37. Moroz P, Emans JB, Hedequist DJ, et al. Outcomes of majorperi-operative neurologic complications in paediatric spine deformity[paper 60]. Presented at: Scoliosis Research Society Annual Meeting;September 10Y13, 2003; Quebec City, Canada.

38. Hall JE, Herndon WA, Levine CR. Surgical treatment of congenitalscoliosis with or without Harrington instrumentation. J Bone Joint SurgAm. 1981;63:608Y619.

39. Hedequist DJ, Hall JE, Emans JB. The safety and efficacy of spinalinstrumentation in children with congenital spine deformities.Spine. 2004;29:2081Y2086. Discussion 7.

40. Hedequist DJ, Yeon H, Emans JB. The use of allograft as a bone graftsubstitute in patients with congenital spine deformities. Presented at:The 40th Annual Meeting of the Scoliosis Research Society; 2005;Miami, FL.

41. Ruf M, Harms J. Hemivertebra resection by a posterior approach:innovative operative technique and first results. Spine. 2002;27:1116Y1123.

42. Ruf M, Harms J. Pedicle screws in 1- and 2-year-old children: technique,complications, and effect on further growth. Spine. 2002;27:E460YE466.

43. Kim YJ, Otsuka NY, Flynn JM, et al. Surgical treatment of congenitalkyphosis. Spine. 2001;26:2251Y2257.

44. Reddy GP, Higgins CB. Magnetic resonance imaging of congenital heartdisease: evaluation of morphology and function. Semin Roentgenol.2003;38:342Y351.

45. Winter RB. Congenital spine deformity. Natural history and treatment.Isr J Med Sci. 1973;9:719Y727.

46. Winter RB, Moe JH. The results of spinal arthrodesis for congenitalspinal deformity in patients younger than five years old. J Bone JointSurg Am. 1982;64:419Y432.

47. Kesling KL, Lonstein JE, Denis F, et al. The crankshaft phenomenonafter posterior spinal arthrodesis for congenital scoliosis: a reviewof 54 patients. Spine. 2003;28:267Y271.

48. Terek RM, Wehner J, Lubicky JP. Crankshaft phenomenon in congenitalscoliosis: a preliminary report. J Pediatr Orthop. 1991;11:527Y532.

49. Al-Sayyad MJ, Crawford AH, Wolf RK. Early experiences withvideo-assisted thoracoscopic surgery: our first 70 cases. Spine.2004;29:1945Y1951. Discussion 52.

50. Newton PO, White KK, Faro F, et al. The success of thoracoscopicanterior fusion in a consecutive series of 112 pediatric spinal deformitycases. Spine. 2005;30:392Y398.

51. Thompson AG, Marks DS, Sayampanathan SR, et al. Long-term resultsof combined anterior and posterior convex epiphysiodesis for congenitalscoliosis due to hemivertebrae. Spine. 1995;20:1380Y1385.

52. Winter RB, Lonstein JE, Denis F, et al. Convex growth arrest forprogressive congenital scoliosis due to hemivertebrae. J Pediatr Orthop.1988;8:633Y638.

53. Klemme WR, Polly DW Jr, Orchowski JR. Hemivertebral excision forcongenital scoliosis in very young children. J Pediatr Orthop.2001;21:761Y764.

54. Ruf M, Harms J. Posterior hemivertebra resection with transpedicularinstrumentation: early correction in children aged 1 to 6 years. Spine.2003;28:2132Y2138.

55. Bollini G, Docquier PL, Viehweger E, et al. Lumbar hemivertebraresection. J Bone Joint Surg Am. 2006;88:1043Y1052.

56. Hedequist DJ, Hall JE, Emans JB. Hemivertebra excision in children viasimultaneous anterior and posterior exposures. J Pediatr Orthop.2005;25:60Y63.

57. Shimode M, Kojima T, Sowa K. Spinal wedge osteotomy by a singleposterior approach for correction of severe and rigid kyphosis orkyphoscoliosis. Spine. 2002;27:2260Y2267.

58. Shono Y, Abumi K, Kaneda K. One-stage posterior hemivertebraresection and correction using segmental posterior instrumentation.Spine. 2001;26:752Y757.

59. Suk SI, Kim JH, Kim WJ, et al. Posterior vertebral column resection forsevere spinal deformities. Spine. 2002;27:2374Y2382.

60. Nakamura H, Matsuda H, Konishi S, et al. Single-stage excision ofhemivertebrae via the posterior approach alone for congenital spine




deformity: follow-up period longer than ten years. Spine. 2002;27:110Y115.

61. Smith JT, Gollogly S, Dunn HK. Simultaneous anterior-posteriorapproach through a costotransversectomy for the treatment of congenitalkyphosis and acquired kyphoscoliotic deformities. J Bone Joint Surg Am.2005;87:2281Y2289.

62. Sink EL, Karol LA, Sanders J, et al. Efficacy of perioperativehalo-gravity traction in the treatment of severe scoliosis in children.J Pediatr Orthop. 2001;21:519Y524.

63. Rinella A, Lenke L, Whitaker C, et al. Perioperative halo-gravity traction inthe treatment of severe scoliosis and kyphosis. Spine. 2005;30:475Y482.

64. Mehlman CT, Al-Sayyad MJ, Crawford AH. Effectiveness of spinalrelease and halo-femoral traction in the management of severe spinaldeformity. J Pediatr Orthop. 2004;24:667Y673.

65. Emans JB, Kassab F, Caubet JF, et al. Earlier and more extensivethoracic fusion is associated with diminished pulmonary function.Outcome after spinal fusion of 4 or more thoracic spinal segments beforeage 5 [paper 101]. Presented at: Scoliosis Research Society AnnualMeeting; September 6Y9, 2004; Buenos Aires, Argentina.

66. Harrington PR. Scoliosis in the growing spine. Pediatr Clin North Am.1963;10:225Y245.

67. Moe JH, Kharrat K, Winter RB, et al. Harrington instrumentation withoutfusion plus external orthotic support for the treatment of difficult

curvature problems in young children. Clin Orthop Relat Res. 1984:35Y45.

68. Blakemore LC, Scoles PV, Poe-Kochert C, et al. Submuscular Isolarod with or without limited apical fusion in the management of severespinal deformities in young children: preliminary report. Spine. 2001;26:2044Y2048.

69. Akbarnia BA, Marks DS, Boachie-Adjei O, et al. Dual growing rodtechnique for the treatment of progressive early-onset scoliosis: amulticenter study. Spine. 2005;30:S46YS57.

70. Thompson GH, Akbarnia BA, Kostial P, et al. Comparison of single anddual growing rod techniques followed through definitive surgery: apreliminary study. Spine. 2005;30:2039Y2044.

71. Campbell RM Jr, Smith MD, Mayes TC, et al. The effect of openingwedge thoracostomy on thoracic insufficiency syndrome associated withfused ribs and congenital scoliosis. J Bone Joint Surg Am. 2004;86-A:1659Y1674.

72. Campbell RM Jr, Smith MD, Hell-Vocke AK. Expansion thoracoplasty:the surgical technique of opening-wedge thoracostomy. Surgicaltechnique. J Bone Joint Surg Am. 2004;86-A(suppl 1):51Y64.

73. Gollogly S, Smith JT, White SK, et al. The volume of lung parenchymaas a function of age: a review of 1050 normal CT scans of the chest withthree-dimensional volumetric reconstruction of the pulmonary system.Spine. 2004;29:2061Y2066.




Cong scoliosis

Education

Transcript of Cong scoliosis