Surgical Technique Guide - zimmerbiomet.com · treatment and correction of traumatic and pathologic...

Surgical Technique Guide

The following general Surgical Technique Guide is for illustrative purposes only. As with all surgical procedures, the technique used in each case will depend on the surgeon’s medical judgment as to the best treatment for each patient. Only those individuals with specialized training and experience in spinal surgery should attempt to use the Snowcap system. Detailed preoperative clinical and diagnostic evaluation followed by carefully executed surgical technique is required. Detailed preoperative planning is also essential. Refer to the Instructions For Use (IFU) for a complete list of prescribing information.

A low-profile plate with an efficient, secure locking mechanism that reduces retraction and the possibility of dysphagia, while preventing screw back-out.

2 BIOMET SPINE

16 mm

The Snowcap® Anterior Cervical Plate System is designed with smooth contours and flush-fitting locking caps engineered for ease of insertion and placement. Prescribed for the surgical treatment and correction of traumatic and pathologic conditions of the cervical spine, the Snowcap system consists of a wide range of titanium alloy plates, screws (fixed and variable, self-drilling and self-tapping) and locking caps with comprehensive instrumentation.

FEATURES •Lockingcapsystemthatpreventsscrewback-out.

•�1.9mmlow-profile,titaniumalloyplate.

•Largevisualizationwindowforoptimizedplateplacementandfusionverification.

•Pre-contouredplatesaccommodating1,�2,�3and4levels.

•Fixedandvariablescrewsinself-drillingandself-tappingdesignsallowforflexibilityinhybridplateconstructs.

•Simple,intuitiveinstrumentation.+8º+16º

0º

1.9mm

SNOWCAP® ANTERIOR CERVICAL PLATE SYSTEM SURGICAL TECHNIQUE GUIDE 3

PREOPERATIVE PREPARATION •Reviewandinspectallinstrumentationandimplants

priortosterilization.

•Replaceoraddanynecessarycomponentsfortheplannedsurgery.

•Surgeonmustbefullyexperiencedwiththerequiredspinalfusiontechniques.

SURGICAL EXPOSURE •Positionanddrapethepatientintheusualfashion(Figure 1).

•Exposetheaffectedlevelsviaastandardanteriorcervicalapproach.

•Performanynecessaryboneandtissueremoval.

•Attheappropriatelevel,discectomyand/orcorpectomyarecompletedandbonegraftisplaced.

MAYO STAND

C-ARM MONITOR

C-ARM

Figure1

4 BIOMET SPINE

SITE PREPARATION

1.After preparing the intervertebral disc space, the trials are inserted to determine the size of the desired implant.

•Selectanappropriateplateandplaceagainsttheanteriorcervicalspinetodeterminethecorrectlengthandcontour.Ifadditionalplatecontouringisdesired,thecervical plate benderisused.

•Theremovableanvil mustbeattachedtotheplatebenderinthecorrectorientation.Thisallowsthesurgeontoeitherincreaseordecreaselordosisasneeded.

•Ifincreasingthelordosis(addingcurvaturetotheplate),inserttheanvilwith+LORDOSIStowardstheplate.Makesurethearrowontheanvilisinsertedtowardsthearrowontheplatebender.Thehammerisalsomovedsothe“+”istowardstheplatetobebent(Figure 2a).

•Todecreaselordosis(flattentheplate),rotatethehammerwiththe“-”towardstheplateandplacetheanvilwith-LORDOSISfacingupward.

•Thepostontheanvilisalwayspositionedintherearandisusedtoproperlyaligntheplatebetweenthehammerandanvil.Donotplacetheplateoverthepost(Figure 2b).

Note: Bend plates over graft window area. Avoid deforming plate screw holes. Caution: Multiple bends may fatigue the plate. Minimal bending is recommended.

2. •Theplate holdersecuresontotheplateandaidsinpositioning

duringplatesizeselection.

ANVIL

POST

HAMMER

Figure2a

Figure2b


PREPARING SCREW HOLES

3. •Temporaryfixation pinsareinsertedusingthetemporary pin inserter andscrewedintoposition.

•Forassembly,retracttheoutersleeveofthetemporarypininserterwhileinsertingtheshankofthetemporarypinintotheinserter,simultaneouslyaligningthehexdrives.

•Tolock,releasetheoutersleeveofthetemporarypininserter(Figure 3).

4. •Theshieldedvariableawlhasaspring-loadeddistaltipthat

canprotrudeupto10mm.

•Thetrajectoryofthevariableawlshouldbeinlinewiththedesiredscrewangle.

5. •Thefixedawlpenetrates8 mmindepthandisusedwiththe

fixeddrillguides(Figure 4).

Figure3

Figure4

LOCK UNLOCK

Self-drilling and self-tapping screws are available in the set. When using the self-tapping screws, the anterior cortex may be penetrated with either an awl or the drill. There are two awls available in the instrument tray, the shielded variable awl and the fixed awl.

6 BIOMET SPINE

Fixed Screws

End Holes�� 8°Medial8°Caudal/Cephalad

Middle Holes 8°Medial0°Caudal/Cephalad

Fixed screws follow the nominal trajectory ONLY.

Variable Screws

Range of Motion 16°ConeofAngulation

End Holes 0°�–�16°Medial0°�–�16°Caudal/Cephalad

Middle Holes 0°�–�16°Medial-8°to+8°Caudal/Cephalad

SCREW TRAJECTORIES

MEDIAL/LATERAL VIEW

8º

Nominal

0º 16º

CAUDAL/CEPHALAD VIEW

0º+8º -8º8º

Nominal Nominal

0º16º


6. •TheENDfixedangledrillguideisusedfordrillingthecaudaland

cephaladscrewholes.The“pistolgrip”opensandclosestheplateattachmentarm,whichgripstheplate’svisualizationwindow.Itcanonlybeseatedontheplateinoneorientation.TheENDfixedangledrillguidetrajectoryissetat8°caudal/cephaladand8°medial(Figure 5).

7. •TheMIDDLEfixedangledrillguideisusedfordrillingthe

middlescrewholesin2-,�3-�and4-levelplates.The“pistolgrip”opensandclosestheplateattachmentarm,whichgripstheplate’svisualizationwindow.Itcanbeseatedontheplateineitherorientation.TheMIDDLEfixedangleguidedrilltrajectoryissetat�0°caudal/cephaladand8°medial(Figure 6).

8. •A variable angle single barrel drill guideisusedwhenitis

necessarytovarythescrewangleateachhole.

•Thevariableangledrillguideallowsforindividualscrewtrajectorybutshouldbedirectednomorethan8°fromnominal.Thisdrillguidecanonlybeusedwiththedrillbits(Figure 7).

Note: The drill bits are universal for both the fixed drill guides and the variable drill guide.

Figure5

DRILLING FOR FIXED ANGLE SCREWS

DRILLING FOR VARIABLE ANGLE SCREWS

Figure6

Figure7

There are separate fixed angled, double barrel drill guides for either the END or the MIDDLE holes in the plate. The fixed drill guides can be used for holding the plate in position. The use of the fixed awl, drills and fixed tap can be completed through the fixed drill guides for placement of fixed or variable screws.

8 BIOMET SPINE

9. •Theinstrumenttraycontainstwotaps,oneforvariableanglescrewsandtheotherforfixedanglescrews.

•Thevariable tapwillnotpenetratebeyond10mm(Figure 8).

•Thefixed tap,whichfitsdownthefixeddrillguides,willnotpenetratebeyond11mm(Figure 9).

10. •Thesplit hex driverisusedtoinsertthescrewsthrough

theplateandintothevertebralbody.

•Thescrewisheldbyafrictionfitbetweenthehexdriverandthescrewhead(Figure 10).

•Insertthescrewintothepreviouslypreparedscrewhole.

•Advancethescrewfullyintotheplatealternatingproximally,distallyandcontralaterallyuntilallscrewshavebeenplaced.

•Confirmcorrectalignment,placementandtrajectoryofthescrewradiographically.

Tip: If the hex driver sticks in the screw head, gently “wiggle” to disengage.

Figure8 Figure9

Figure10

TAPPING

INSERTING SCREWS

The Snowcap® Anterior Cervical Plate System provides self-tapping and self-drilling screws, which can be used at the discretion of the surgeon.


11.Assemble the locking cap inserter.

•Selectthelockingcapinserter shaftandslidethelockingcap inserter sleeveovertheshaft(Figure 11).

12.Load the locking caps into the locking cap inserter.

•Slidethesleeveofthelockingcapinsertertowardsthehandletotheunlockposition.

•Openthelockingcapcaddytoexposethefirsttwolockingcaps(additionallockingcapscanbeexposedbyincrementallyslidingthecaddylid).

•Inserttipsoflockingcapinserterthroughthetwoholesinthelockingcap.

•Whilethetipsofthelockingcapinserterareengagedinthetwoholesofthelockingcap,slidetheinsertersleevedownwardsintothelockposition.

SECURING LOCKING CAPS INTO THE SNOWCAP ANTERIOR CERVICAL PLATE

Figure11

Both variable and fixed style screws are covered by the locking cap to prevent screw back-out. The locking cap is designed to lock into the plate, and fits flush with the plate surface.

Note: High angle locking caps are available if the standard locking cap does not fit over the screw head.

Precaution: Locking caps are for single insertion and must not be reused after locking into the plate assembly.

10 BIOMET SPINE

Figure12a

Figure12b

Figure13

13.Secure the locking caps.

•Alignandinsertthetabsofthelockingcapwiththerectangularrecessaroundtheplatescrewholes(Figure 12a).

•Rotatethelockingcapclockwiseapproximately30°.�Thelockingcaptabswillrotatearoundtheplate’sscrewholeinanundercut(Figure 12b).

•Atactileclickmaybefeltasthetabsrideoverthelockingdetent,designedtolockthelockingcap,preventingmigration.

•Slidethelockingcapinsertersleeveupwardtowardsthehandletodisengagethelockingcapinserterfromthelockingcap.

•VisuallyconfirmthelockingcapsareintheirfinalsecurepositionbyverifyingthetwoholesinthelockingcapsarehorizontaltothelongitudinalaxisoftheSnowcap®AnteriorCervicalPlate.Additionally,confirmthelockingcaptabsareNOTvisible(Figure 13).

SECURING LOCKING CAPS INTO THE SNOWCAP® ANTERIOR CERVICAL PLATE (CONTINUED)


CLOSURE

REMOVING THE SNOWCAP® PLATE (IF NECESSARY)

1.Usingthelockingcapinserterorthelocking cap removal instrument,removethelockingcapsbyrotatingthemcounterclockwiseapproximately30°.

2.Thelockingcaptabswillrotatearoundtheplate’sscrewholeinanundercut.Atactileclickmaybefeltasthetabspassthelockingdetent.Whenusingthelockingcapremovalinstrument,cautionshouldbeobserved.Whenretrievingthelockingcapfromthewound,forcepsarerecommendedforcapretrieval.

3.Removethescrewsfromtheplateusingthesplit hex driver.

� 4.Onceallthelockingcapsandscrewshavebeenremoved,theSnowcapAnteriorCervicalPlatecanberemovedusingtheplate holder.

14. •Closewoundanddressintheusualfashion.

12 BIOMET SPINE

Plate Holder • 4434-0010

Cervical Plate Bender • 4404-1020 Plate Bender Anvil • 4434-0022

Variable, Single Barrel Drill Guide • 4434-0014

Fixed, End, Double Barrel Drill Guide • 4434-0020

Fixed, Middle, Double Barrel Drill Guide • 4434-0021

SNOWCAP® INSTRUMENTS

Plate Assembly Driver • 4404-1017

Locking Cap Slide Inserter • 4434-0002

Locking Cap Slide Inserter Shaft • 4434-0002-001

Locking Cap Slide Inserter Sleeve • 4434-0002-002

Locking Cap Removal Instrument • 4434-0003

Drill Handle, Manual • 4404-1007

Temporary Pin Inserter • 4404-1016

Variable Tap • 4404-1003

Split Hex Driver • 4434-0028

Fixed Awl • 4404-0013

Fixed Tap • 4404-0012

Shielded Variable Awl • 4434-0001

Drill Bit

10mm 4434-0210

12mm 4434-0212

14mm 4434-0214

16mm 4434-0216


1 Level Plates

Part # Length

4431-1018 18mm

4431-1020 20mm

4431-1022 22mm

4431-1024 24mm

4431-1026 26mm

4431-1028 28mm

4431-1030 30mm

Self-Drilling Screws — Fixed

Part # Diameter Length

4432-1410 4mm 10mm

4432-1412 4mm 12mm

4432-1414 4mm 14mm

4432-1416 4mm 16mm

Locking Cap

Part # Description Color

4433-2001 Standard Gold Locking Cap

4433-2106 High Angle Green Locking Cap 1.5mm

4433-2104 High Angle Grey Locking Cap 2.0mm

Self-Tapping Screws — Fixed


4432-2410 4mm 10mm

4432-2412 4mm 12mm

4432-2414 4mm 14mm

4432-2416 4mm 16mm

4432-2512 4.35mm 12mm

4432-2514 4.35mm 14mm

4432-2516 4.35mm 16mm

Self-Tapping Screws — Variable


4432-4410 4mm 10mm

4432-4412 4mm 12mm

4432-4414 4mm 14mm

4432-4416 4mm 16mm

4432-4512 4.35mm 12mm

4432-4514 4.35mm 14mm

4432-4516 4.35mm 16mm

Self-Drilling Screws — Variable


4432-3410 4mm 10mm

4432-3412 4mm 12mm

4432-3414 4mm 14mm

4432-3416 4mm 16mm

3 Level Plates

Part # Length

4431-3050* 50mm

4431-3053 53mm

4431-3056 56mm

4431-3059 59mm

4431-3062 62mm

4431-3065 65mm

4431-3068 68mm

4431-3071 71mm

4431-3074 74mm

4431-3077 77mm

2 Level Plates

Part # Length

4431-2032 32mm

4431-2034 34mm

4431-2036 36mm

4431-2038 38mm

4431-2041 41mm

4431-2044 44mm

4431-2047 47mm

4431-2050 50mm

4431-2053 53mm

4 Level Plates*

Part # Length

4431-4068 68mm

4431-4072 72mm

4431-4076 76mm

4431-4080 80mm

4431-4084 84mm

4431-4088 88mm

4431-4092 92mm

SELF- DRILLING

Screw length is measured from underside of plate to tip of screw (Bone Purchase)

SELF- TAPPING

SCR

EW L

ENG

TH

MEA

SUR

EMEN

T

* Special Order

SNOWCAP® MEASUREMENTS

Plates

Screws

• Plate Profile: 1.9mm• Plates are sized by the overall length• Screw hole distance is the overall plate length

minus 8mm

SCREW HOLE

DISTANCE

PLATE WIDTH 16 MM

PLATE LENGTH MEASUREMENT

14 BIOMET SPINE

IMPORTANT INFORMATION ON THE SNOWCAP® ANTERIOR CERVICAL PLATE SYSTEM

DEVICE DESCRIPTIONTheSnowcap®systemisaspinalintervertebralbodyfixationorthosis.TheSnowcapsystemismadeupofmetallicplatesfixedtotheanteriorcervicalspinewithscrews.Thedeviceconsistsofthefollowingmajorcomponentsandaccessories:anteriorcervicalplates,bonescrewsandlockingcaps,aswellasassociatedinstrumentsforsitepreparationandimplantinsertion,andsterilizationcases.

INDICATIONS FOR USETheSnowcapsystemisintendedforanteriorinterbodyfixationofthecervicalspine.Thesystemissuitableforusetoprovidetemporarystabilizationoftheanteriorspinewhileawaitingbonyfusion(healing)inskeletallymaturepatientswithdegenerativediscdisease(neckorradicularpainofdiscogenicorigindegenerationofthediscconfirmedbypatienthistoryandradiographicstudies),trauma(includingfractures),tumors,deformity(kyphosis,lordosisorscoliosis),orpseudoarthrosisand/orfailedpreviousfusionbetweenandincludingcervicallevelsC2andC7.

Warning:Thisdeviceisnotclearedforscrewattachmenttotheposteriorelements(pedicles)ofthecervical,thoracicorlumbarspine.

CONTRAINDICATIONSContraindicationsmayberelativeorabsolute.Thechoiceofaparticulardevicemustbecarefullyweighedagainstthepatient’soverallevaluation.Circumstanceslistedbelowmayreducethechanceofasuccessfuloutcome.Contraindicationsinclude,butarenotlimitedto:

•Allergytotitanium,orforeignbodysensitivity.Wherematerialsensitivityissuspected,appropriatetestsshouldbemadepriortoimplantation.

•Knownorsuspectedinfection/immunesystemincompetence.Acuteorchronicinfectiousdiseasesofanyetiologyorlocalization.

•Anyabnormalitypresentwhichaffectsthenormalprocessofboneremodelingincluding,butnotlimitedto,severeosteoporosisinvolvingthespine,boneabsorption,osteopenia,activeinfectionatthesiteorcertainmetabolicdisordersaffectingosteogenesis.

•MorbidObesity.Anoverweightorobesepatientcanproduceloadsonthespinalsystem,whichcanleadtofailureofthefixationofthedeviceorfailureofthedeviceitself.

•Anyneuromusculardeficitwhichplacesanunusuallyheavyloadonthedeviceduringthehealingperiod.

•OpenWounds.

•Pregnancy.

•Anyothermedicalorsurgicalconditionwhichwouldprecludethepotentialbenefitofspinalsurgery,suchasthepresenceofcongenitalabnormalities,elevationofsedimentationrateunexplainedbyotherdiseases,elevationofthewhitebloodcell(WBC)count,oramarkedleftshiftintheWBCdifferentialcount.

•Anycaserequiringthemixingofcomponentsfromothermanufacturers’systems.

•Anycaserequiringthemixtureofstainlesssteelwithtitaniumorstainlesssteelwithcobaltchromeimplantcomponents.

•Feverorleukocytosis.

•Signsoflocalinfectionorinflammation.

•Previoushistoryofinfection.

•Alcoholismorheavysmoking.

•Senility,mentalillnessorsubstanceabuse,ofaseveritythatthepatientmayignorecertainnecessarylimitationsandprecautionsintheuseoftheimplant,leadingtofailureorothercomplications.

•Anypatientunwillingtofollowpostoperativeinstructions.

•Inadequatetissuecoverageovertheoperativesite.

POSSIBLE COMPLICATIONSPossiblecomplicationsspecifictothedevicemayinclude:

•Earlyorlateimplantbending,breakage,failure,looseningormovement/migration.

•Bonefracture.

•Allergicreactiontoimplantmaterial.

•Othergeneralcomplicationsassociatedwithanyspinalsurgicalproceduremayinclude:Non-unionordelayedunion,pseudoarthrosis;pain;secondsurgery;bleeding;infection,earlyandlate;tissueornervedamage,includingduraltearsorotherneurologicalproblems;incisionalcomplications;scarformation;damagetobloodvesselsandcardiovascularsystemcompromise;changesinmentalstatus;damagetointernalorgansandconnectivetissue;complicationsduetotheuseofbonegrafting,includinggraftdonorsitecomplications;respiratoryproblems;reactionstoanesthesiaand/ordeath.


WARNINGSAsuccessfulresultisnotalwaysachievedineverysurgicalcase.Thisfactisespeciallytrueinspinalsurgery,wheremanyextenuatingcircumstancesmaycompromisetheresults.

PRECAUTIONS •TheSnowcapimplantsareforsingleuseonly.Neverreuseany

implantevenifitappearsunmarkedorundamaged.Reuseoftheimplantcomponentsmayresultinreducedmechanicalperformance,malfunctionorfailureofthedevice.Anyimplantimplantedandthenremovedmustbediscarded.Useonlynewimplantsforeachcase.

•Theimplantationofanteriorcervicalspinalinstrumentationshouldbeperformedonlybyexperiencedspinalsurgeonswithspecifictrainingintheuseofsuchspinalsystems.Thisisatechnicallydemandingprocedurepresentingariskofseriousinjurytothepatient.

•Basedonthefatiguetestingresults,thephysician/surgeonmustconsiderthelevelsofimplantation,patientweight,patientactivitylevel,otherpatientconditions,etc.whichmayimpactontheperformanceofthesystem.

•Tohelpensureasuccessfulimplantation,properhandlingoftheimplantbeforeandduringtheoperationiscrucial.

•Preoperatively:Thesurgeonmustbefullyconversantwithallaspectsofthesurgicaltechniqueandknowtheindicationsandcontraindicationsofthistypeofimplant.Thesurgeonmusthaveacquaintedthemselvesbeforetheoperationwiththespecifictechniqueforinsertionoftheproduct,whichisavailablefromthemanufacturer.Aspartofthepreoperativeexamination,thesurgeonmustcheckthatnobiological,biomechanicalorotherfactorswillaffectthecorrectconductoftheoperationandthepostoperativeperiod.Anappropriaterangeofsizesmustbeavailableatthetimeoftheoperation.

•Explaintherisksassociatedwithneurosurgery,generalsurgery,orthopedicsurgeryandtheuseofgeneralanesthesiatothepatientbeforesurgery.Itisrecommendedthattheadvantagesanddisadvantagesofusingimplants,aswellasalternativetreatmentmethods,areexplainedtothepatient.

•Intraoperatively:Thecorrectselectionofthetypeandsizeofimplantappropriatetothepatientandthepositioningoftheimplantareextremelyimportant.

•Beforeuse,inspectallinstrumentationforpossibledamage,wearornon-function.Donotuseorprocessdamagedordefectiveinstruments.ContactyourlocalBIOMETSPINErepresentativeforrepairorreplacement.

•Theuseofaninstrumentfortasksotherthanthoseforwhichtheyareindicatedmayresultindamagedorbrokeninstrumentsandunpredictablesurgicaloutcomes.

•Donotapplyexcessiveforceorstress.Misusecandamageinstrumentsorimplants.

•TheSnowcapdevicehasnotbeentestedforsafetyandcompatibilityinthemagneticresonance(MR)environment.TheSnowcapdevicehasnotbeentestedforheatingormigrationintheMRenvironment.

•Mixingofdissimilarmetalscanaccelerateorinitiatethecorrosionprocess.TitaniumcomponentsmustNOTbeusedtogetherinbuildingaconstructthatinvolvesotherimplantmaterials.Titaniumandcobaltchromemaybeusedtogetherwithinthesameconstruct.

STERILIZATION •TheSnowcapsystemimplantsandinstrumentsaresupplied

non-sterileandmustbecleanedandsterilizedpriortouse.Therecommendedsterilizationprocessissteamautoclavesterilization,usingtheparameterslistedinthetablesbelow.

•UseofaFDA-clearedwrapisrecommendedtomaintainsterilitypriortouse.

WhereImmediateUseSteamSterilization(IUSS)isneeded,eachoftheSnowcapManualSurgicalInstrumentsmaybesterilizedindividuallyusingthefollowingsterilizationparameters.

TherecommendedsterilizationcycleshavebeenvalidatedtoassureaSterilityAssuranceLevel(SAL)ofatleast10-6.

Method Cycle Temperature Exposure Time Minimum Drying Time

Steam Prevacuum 132˚ C (270˚ F) 4 minutes 30 minutes

Steam Gravity 132˚ C (270˚ F) 30 minutes 40 minutes

Snowcap® System Instrument and Implant Sterilization Parameters

Method Cycle Temperature Exposure Time

Steam Prevacuum 132˚ C (270˚ F) 3 minutes

Snowcap® System Single Instrument IUSS Parameters

IMPORTANT INFORMATION ON THE SNOWCAP® ANTERIOR CERVICAL PLATE SYSTEM

PRODUCT COMPLAINTS — Communicate suspected deficiencies in product quality, identity, durability, reliability, safety, effectiveness and/or performance directly to BIOMET SPINE by email: [email protected] or phone: 866.956.7579. When filing a complaint, please provide the component name(s), part number(s), lot number(s), your name and address, the nature of the complaint, surgeon name and the date you became aware of the complaint. Sterilize and return all component(s) to your local BIOMET SPINE representative. Notify BIOMET SPINE immediately of an incident resulting in patient death or serious injury.

If further directions for use of this system are needed, contact BIOMET SPINE Customer Service by email: [email protected], phone: 866.378.4195 or fax: 303.443.7501.

At BIOMET, engineering excellence is our heritage and our passion. For over 25 years, through various divisions worldwide, we have applied the most advanced engineering and manufacturing technology to the development of highly durable systems for a wide variety of surgical applications.

To learn more about this product, contact your local BIOMET Sales Representative today.

Broomfield, CO • 800.447.3625www.biomet.com • LIT9900-46.08

©2014 BIOMET SPINE, LLC. All rights reserved. All trademarks are the property of BIOMET, Inc. or one of its subsidiaries, unless otherwise indicated. Rx Only.

Surgical Technique Guide - zimmerbiomet.com · treatment and correction of traumatic and pathologic...

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