Fracture FixationFracture Fixation Internal & ExternalInternal & External

Fracture TypesFracture Types

http://health.allrefer.com/health/bone-fracture-repair-fracture-types-1.html

Influencing HealingInfluencing Healing

Systemic FactorsSystemic Factors AgeAge HormonesHormones Functional activityFunctional activity Nerve functionNerve function NutritionNutrition Drugs (NSAID)Drugs (NSAID)

Local FactorsLocal Factors Energy of traumaEnergy of trauma

Degree of bone lossDegree of bone loss Vascular injuryVascular injury InfectionInfection

Type of bone fracturedType of bone fractured Degree of immobilizationDegree of immobilization Pathological conditionPathological condition

http://www.orthoteers.co.uk/Nrujp~ij33lm/Orthbonefracheal.htm

Stages of Fracture HealingStages of Fracture Healing

1.1. Inflammation & Inflammation & HematomaHematoma Osteoprogenitor cells, FibroblastsOsteoprogenitor cells, Fibroblasts

2.2. Callus FormationCallus FormationPeriosteal and EndostealPeriosteal and Endosteal

Fibro-cartilage differentiationFibro-cartilage differentiation

3.3. Woven BoneWoven BoneSubstitution of avascular and necrotic tissue Substitution of avascular and necrotic tissue

Haversian remodelingHaversian remodeling

4.4. RemodelingRemodeling Lamellar or trabecular boneLamellar or trabecular bone

Restoration of continuity and ossificationRestoration of continuity and ossification

Bone unionBone union

**When compression is applied via implant, these stages are minimized****When compression is applied via implant, these stages are minimized**

http://www.orthoteers.co.uk/Nrujp~ij33lm/Orthbonefracheal.htm http://www.ivis.org/special_books/ortho/chapter_03/03mast.asp?Type=IPRP&LA=1

Healing ComplicationsHealing Complications Most often due to severe injuryMost often due to severe injury

Energy dissipation to bone and soft tissue results in Energy dissipation to bone and soft tissue results in damage to blood supplydamage to blood supply

Compartment syndromeCompartment syndrome Severe swelling resulting in decreased blood supply can cause the Severe swelling resulting in decreased blood supply can cause the

muscles around the fracture to diemuscles around the fracture to die Bad osmotic pressure lets blood out instead of across damaged muscleBad osmotic pressure lets blood out instead of across damaged muscle

As pressure remains high, blood cannot get to damaged muscleAs pressure remains high, blood cannot get to damaged muscle

Neurovascular injuryNeurovascular injury Arteries and nerves around the injury site are damagedArteries and nerves around the injury site are damaged

InfectionInfection Imbalance of bacteria and body’s ability to cope with it when amount of Imbalance of bacteria and body’s ability to cope with it when amount of

necrotic tissue and contraction of bacteria are not being cleared (by necrotic tissue and contraction of bacteria are not being cleared (by surgeon or patient) surgeon or patient)

http://www.hughston.com/hha/a.fracture.htm

Healing Complications (Cont’d)Healing Complications (Cont’d) Delayed unionDelayed union

Extended healing timeExtended healing time

NonunionNonunion Failure to healFailure to heal

MalunionMalunion Abnormal alignmentAbnormal alignment

Post-traumatic arthritisPost-traumatic arthritis Fractures that extend into the joints can cause premature arthritis of a Fractures that extend into the joints can cause premature arthritis of a

jointjoint

Growth abnormalitiesGrowth abnormalities A fracture through an open physis, or growth plate, could result in A fracture through an open physis, or growth plate, could result in

premature partial or complete closure of the physis; Part or all of a premature partial or complete closure of the physis; Part or all of a bone will stop growing unnaturally earlybone will stop growing unnaturally early

http://www.hughston.com/hha/a.fracture.htm

TreatmentTreatment When will a cast suffice?When will a cast suffice?

Fracture is stableFracture is stable Patient preferencePatient preference No complications (Ex.-infection, burn)No complications (Ex.-infection, burn)

When is fixation necessary?When is fixation necessary? Fracture is unstableFracture is unstable Quick MobilizationQuick Mobilization OccupationOccupation

AthletesAthletes

http://www.defence.gov.au/dpe/dhs/infocentre/publications/journals/NoIDs/ADFHealthApr01/adfhealthapr01_2_1_24-28.pdf

Principles of fracture fixationPrinciples of fracture fixation

Obtain and maintain alignmentObtain and maintain alignment Reduction Reduction

Transmission of compressive forces Transmission of compressive forces Minimum motion across fracture siteMinimum motion across fracture site Achieve stabilityAchieve stability

Avoid tensile/ shear/torsion forcesAvoid tensile/ shear/torsion forces Across fracture siteAcross fracture site

Prevent motion in most crucial planePrevent motion in most crucial plane

Fixation: Internal vs. ExternalFixation: Internal vs. External

InternalInternal Plates, screws, etc. completely within the bodyPlates, screws, etc. completely within the body Less expensiveLess expensive TypesTypes

Comminuted – nail with interlocking screwComminuted – nail with interlocking screw Transverse or Oblique –plates or screws Transverse or Oblique –plates or screws

ExternalExternal Pins coming through skin interconnected by external Pins coming through skin interconnected by external

frameframe Has complications Has complications

http://www.defence.gov.au/dpe/dhs/infocentre/publications/journals/NoIDs/ADFHealthApr01/adfhealthapr01_2_1_24-28.pdf

Internal Fixation Internal Fixation

http://www.nlm.nih.gov/medlineplus/ency/imagepages/18023.htm

Internal Fixation PriciplesInternal Fixation Priciples

Rigid, anatomic fixationRigid, anatomic fixation Allows an early return to functionAllows an early return to function

Reserved for those cases that cannot be Reserved for those cases that cannot be reduced and immobilized by external reduced and immobilized by external meansmeans

Open reduction of a fracture Open reduction of a fracture Good blood supply to undisturbed tissuesGood blood supply to undisturbed tissues

http://www.umm.edu/ency/article/002966.htm

Physiological Response to IFPhysiological Response to IF

Primary healingPrimary healing Minimal extramedullary callusMinimal extramedullary callus Minimal intra-medullary callusMinimal intra-medullary callus Sub-periostealSub-periosteal RapidRapid

Related to motionRelated to motion Crosses miniature gapsCrosses miniature gaps Depends on soft tissue viability Depends on soft tissue viability

Stress ConcentrationsStress Concentrations

Geometric discontinuities (hole, base of Geometric discontinuities (hole, base of threaded screw, corner)threaded screw, corner) Local disturbance in stress patternLocal disturbance in stress pattern High stresses at site of discontinuityHigh stresses at site of discontinuity

Drilling a hole reduces the bone strength Drilling a hole reduces the bone strength by 10 – 40 %by 10 – 40 %

Types of IF DevicesTypes of IF Devices

Lag screwsLag screws Kirschner wireKirschner wire Wire loopWire loop

Tension band wiringTension band wiring Combination of wire loop and screwCombination of wire loop and screw Combination of Kirschner and wire loopCombination of Kirschner and wire loop

PlatePlate Intramedullary rods and nailsIntramedullary rods and nails

Interlocking screwsInterlocking screws

Hemi-ArthroplastyHemi-Arthroplasty

In the hip, used for In the hip, used for femoral neck fracturesfemoral neck fractures

Avascular necrosisAvascular necrosis Fractures of the proximal Fractures of the proximal

humerushumerus Early mobilization is Early mobilization is

facilitatedfacilitated

http://www.orthogastonia.com/patient_ed/html_pages/hip/hip_hemiarthrooplasty.html

Bilboquet DeviceBilboquet Device

http://www.maitrise-orthop.com/corpusmaitri/orthopaedic/100_bilboquet/bilboquet_us.shtml

Problems in IFProblems in IF

InfectionInfection

Delayed unionDelayed union

Non-unionNon-union

External Fixation External Fixation

http://www.nlm.nih.gov/medlineplus/ency/imagepages/18021.htm

External FixationExternal Fixation

Method of immobilizing fracturesMethod of immobilizing fractures Employing percutaneous pins in bone Employing percutaneous pins in bone

attached toattached to Rigid external metalRigid external metal Plastic framePlastic frame

For treatment of For treatment of openopen and infected and infected fracturesfractures

Indications for EFIndications for EF

Open grade III fracturesOpen grade III fractures Compound tibia fracturesCompound tibia fractures

Generally from motorcycle injuries Generally from motorcycle injuries

Gunshot woundsGunshot wounds Major thermal injuriesMajor thermal injuries Open fractures associated with polytraumaOpen fractures associated with polytrauma Management of infected nonunionsManagement of infected nonunions

Forces in an External FixatorForces in an External Fixator

CompressionCompression NeutralizationNeutralization DistractionDistraction AngulationAngulation RotationRotation Translation or displacementTranslation or displacement

CompressionCompression

For transverse For transverse fracturesfractures

Adds stability Adds stability at nonunion at nonunion sitesite

NeutralizationNeutralization

For comminuted For comminuted fracturefracture

Compression may Compression may lead to excessive lead to excessive shorteningshortening

Used to maintain:Used to maintain: LengthLength AlignmentAlignment StabilityStability

DistractionDistraction

For distal For distal metaphyseal or metaphyseal or intra-articular intra-articular injuriesinjuries

Same principle of Same principle of tractiontraction Distraction of Distraction of

fragmentsfragments Alignment of injuryAlignment of injury

AngulationAngulation

A – unacceptable alignment B – loosening clamps; loss of distr. and compr. force C – after frames completely loosened; angulation is corrected D - compression on distraction forces are reapplied

RotationRotation

Exert rotational Exert rotational forceforce Along longitudinal axisAlong longitudinal axis

Release of forces Release of forces first first

Can be done with Can be done with repositioning pinsrepositioning pins

Most of present Most of present frames cannot apply frames cannot apply rotational forcesrotational forces

Translation or DisplacementTranslation or Displacement

Volkov apparatusVolkov apparatus Double ring unitDouble ring unit Moves one ring in Moves one ring in

parallel to otherparallel to other For translationFor translation

Types of EF DevicesTypes of EF Devices

UnilateralUnilateral BilateralBilateral TriangularTriangular QuadrilateralQuadrilateral Semicircular & Circular ringSemicircular & Circular ring

IlizarovIlizarov

http://www.ilizarov.org.uk/content.htmhttp://www.ilizarov.org.uk/content.htm

Unilateral EFUnilateral EF

Bilateral EFBilateral EF

Triangular EFTriangular EF

Quadrilateral EFQuadrilateral EF

Semicircular and Circular EFSemicircular and Circular EF

Advantages of EFAdvantages of EF

Easy applicationEasy application Good stabilityGood stability Excellent pain reliefExcellent pain relief AdjustableAdjustable

Alignment, Angulation, RotationAlignment, Angulation, Rotation Access to open woundsAccess to open wounds

Frequent dressing changeFrequent dressing change Monitoring of damaged tissueMonitoring of damaged tissue

Disadvantages of EFDisadvantages of EF

Application may cause soft tissue damageApplication may cause soft tissue damage Lacks advantages of cyclic loadings as Lacks advantages of cyclic loadings as

seen in castsseen in casts Constrained in timeConstrained in time Pins may drainPins may drain

InfectionInfection

The EndThe End

GranulationGranulation

Tissue damage repair Tissue damage repair begins with growth of begins with growth of new capillariesnew capillaries Red dots are new Red dots are new

clusters of capillariesclusters of capillaries Bleed easilyBleed easily

Bright red tissue of a Bright red tissue of a healing burn is healing burn is granulation tissuegranulation tissue

http://medweb.bham.ac.uk/http/depts/path/Teaching/FOUNDAT/repair/grantiss.html

HematomaHematoma

Blood collection localized to an organ or tissueBlood collection localized to an organ or tissue Usually clottedUsually clotted Example: Contusions (bruises), black eye, blood Example: Contusions (bruises), black eye, blood

collection beneath finger or toenailcollection beneath finger or toenail Almost always present with a fractureAlmost always present with a fracture

http://www.healthscout.com/ency/68/677/main.html

FibrocartilageFibrocartilage Cartilage with a fibrous matrix and approaching Cartilage with a fibrous matrix and approaching

fibrous connective tissue in structurefibrous connective tissue in structure Produced by fibroblastsProduced by fibroblasts

Forms in areas where size of the fracture gap is 1mm Forms in areas where size of the fracture gap is 1mm or greater or greater

Subsequently replaced by boneSubsequently replaced by bone Mechanical properties inferior to other types of Mechanical properties inferior to other types of

cartilagecartilage Contains:Contains:

Large amounts of collagen type ILarge amounts of collagen type I Reduced amounts of proteoglycansReduced amounts of proteoglycans Collagen type II, found only in cartilageCollagen type II, found only in cartilage

http://www.vetmed.ufl.edu/sacs/notes/Cross-Healing/page9.html http://wberesford.hsc.wvu.edu/histolch6.htm http://www.nuigalway.ie/anatomy/wilkins/practicals/bone/html/bone_1.htmlhttp://www.bm.technion.ac.il/courses/336529/web/Cartilage/major%20types.htm

Inflammation & HematomaInflammation & Hematoma

http://www.ivis.org/special_books/ortho/chapter_03/03F2.jpg

Inflammation & HematomaInflammation & Hematoma

Inflammation begins immediately after a fractureInflammation begins immediately after a fracture Initially consists of Initially consists of hematomahematoma and fibrin clot and fibrin clot

Hemorrhage and cell death at location of Hemorrhage and cell death at location of fracture damagefracture damage

Fibroblasts, mesenchymal cells, osteoprogenitor Fibroblasts, mesenchymal cells, osteoprogenitor cells appear nextcells appear next Formation of granulation tissueFormation of granulation tissue Ingrowth of vascular tissueIngrowth of vascular tissue Migration of mesenchymal cellsMigration of mesenchymal cells

http://www.aans.org/education/journal/neurosurgical/apr01/10-4-1.pdf Simon, SR. Simon, SR. Orthopaedic Basic ScienceOrthopaedic Basic Science. Ohio: American Academy of Orthopaedic Surgeons; 1994.. Ohio: American Academy of Orthopaedic Surgeons; 1994.

Inflammation & Hematoma (Cont’d)Inflammation & Hematoma (Cont’d)

http://www.healthscout.com/ency/68/677/main.html

Primary nutrient and oxygen supply provided by Primary nutrient and oxygen supply provided by exposed cancellous bone and muscleexposed cancellous bone and muscle

Use of anti-inflammatory or cytotoxic medication Use of anti-inflammatory or cytotoxic medication during first week may alter the inflammatory during first week may alter the inflammatory response and inhibit bone healingresponse and inhibit bone healing

Callus FormationCallus Formation

http://www.ivis.org/special_books/ortho/chapter_03/03mast.asp?Type=IPRP&LA=1

Callus FormationCallus Formation

Begins when pain and swelling subsideBegins when pain and swelling subside Size inversely dependent on immobilization of Size inversely dependent on immobilization of

fracturefracture Mesenchymal cells form cells which become Mesenchymal cells form cells which become

cartilage, bone, or fibrous tissuecartilage, bone, or fibrous tissue Increase in vascularityIncrease in vascularity

Ends when bone fragments are immobilized by Ends when bone fragments are immobilized by tissuetissue Stable enough to prevent deformityStable enough to prevent deformity

Callus does not appear on x-ray imagesCallus does not appear on x-ray images

http://www.orthoteers.co.uk/Nrujp~ij33lm/Orthbonefracheal.htmSimon, SR. Simon, SR. Orthopaedic Basic ScienceOrthopaedic Basic Science. Ohio: American Academy of Orthopaedic Surgeons; 1994.. Ohio: American Academy of Orthopaedic Surgeons; 1994.

Mechanical RoleMechanical Role

Enlarge diameter at fracture siteEnlarge diameter at fracture site Reduces mobilityReduces mobility Reduces resulting strain Reduces resulting strain

GranulationGranulation Replaces Hematoma Replaces Hematoma Granulation differentiates intoGranulation differentiates into

Connective tissueConnective tissue Random orientation of collagen fibrilsRandom orientation of collagen fibrils

Their direction reflects the direction of tensile forcesTheir direction reflects the direction of tensile forces

FibrocartilageFibrocartilage

Deformation of CallusDeformation of Callus

Strength of initial Strength of initial reparative tissue is lowreparative tissue is low

If forces surpass the If forces surpass the strength of callusstrength of callus Unstable fractureUnstable fracture Functional load deforms Functional load deforms

fracturefracture Fracture fixation is Fracture fixation is

recommendedrecommended

Woven BoneWoven Bone

Woven BoneWoven Bone Callus changes from cartilaginous tissue to Callus changes from cartilaginous tissue to

woven bonewoven bone Callus mineralized but internal architecture is not Callus mineralized but internal architecture is not

fully matured/arrangedfully matured/arranged Osteon organization is not completeOsteon organization is not complete

Connective tissues and fibrocartilage thickensConnective tissues and fibrocartilage thickens Fracture becomes increasingly stableFracture becomes increasingly stable Mineralization is sensitive to strainMineralization is sensitive to strain Mechanically stable scaffoldMechanically stable scaffold

Increased strength and stiffness with increase of Increased strength and stiffness with increase of new bone joining fragmentsnew bone joining fragments

Simon, SR. Simon, SR. Orthopaedic Basic ScienceOrthopaedic Basic Science. Ohio: American Academy of Orthopaedic Surgeons; 1994.. Ohio: American Academy of Orthopaedic Surgeons; 1994.

Bone RemodelingBone Remodeling

Woven bone becomes lamellar boneWoven bone becomes lamellar bone Bone union occurs at fracture gapBone union occurs at fracture gap

Callus gradually reabsorbed by osteoclasts Callus gradually reabsorbed by osteoclasts Replaced by boneReplaced by bone

Medullary canal reconstitutesMedullary canal reconstitutes Begins within 12 weeks after injuryBegins within 12 weeks after injury May last several yearsMay last several years

http://www.glaciermedicaled.com/bone/bonesc3p2.htmlSimon, SR. Simon, SR. Orthopaedic Basic ScienceOrthopaedic Basic Science. Ohio: American Academy of Orthopaedic Surgeons; 1994.. Ohio: American Academy of Orthopaedic Surgeons; 1994.

Mesenchymal CellsMesenchymal Cells Source of cells for new bone productionSource of cells for new bone production

Derived from bone marrow cellsDerived from bone marrow cells

Intramembranous bone formation Intramembranous bone formation Formation of bone directly from mesenchymal cellsFormation of bone directly from mesenchymal cells

Cells become osteoprogenitor cells then osteoblasts.Cells become osteoprogenitor cells then osteoblasts.

Development of Cartilage modelDevelopment of Cartilage model Mesenchymal cells form a cartilage model of the bone Mesenchymal cells form a cartilage model of the bone

during developmentduring development

http://www.grossmont.edu/shina.alagia/lectures/144/Bone%20physiology.ppthttp://www.ecmjournal.org/journal/supplements/vol005supp02/pdf/vol005supp02a07.pdf

Fracture StabilityFracture Stability Direction of fracture & material (type of bone) Direction of fracture & material (type of bone)

define stabilitydefine stability Definition of direction of force importantDefinition of direction of force important

StableStable Fissure (Hairline) – not complete break, minimal Fissure (Hairline) – not complete break, minimal

traumatrauma Greenstick – crack on outside of “bend”Greenstick – crack on outside of “bend”

UnstableUnstable Comminuted – many bone fragmentsComminuted – many bone fragments Oblique – break at an angleOblique – break at an angle Spiral – corkscrew-like crack patternSpiral – corkscrew-like crack pattern

http://pain.health-info.org/Pain%20Pages/fractures.htm

Lag ScrewLag Screw

Lag ScrewLag Screw

Stability Stability Exerts inter-fragmentary Exerts inter-fragmentary

compressioncompression Static compressionStatic compression

Distal head must be Distal head must be engagedengaged

Screw Holding ForceScrew Holding Force

Increase in area of bone Increase in area of bone within screw threadswithin screw threads

Decrease in pilot hole Decrease in pilot hole sizesize

Increase in length of Increase in length of engaged threaded engaged threaded portionportion Area available to resist Area available to resist

shearshear

Kirschner WireKirschner Wire

Kirschner Wire (Cont’d)Kirschner Wire (Cont’d)

Rotational stabilityRotational stability May be a problemMay be a problem

Anchorage to tension bandAnchorage to tension band Twisting of wires on both sides Twisting of wires on both sides

Almost equally distributed compressionAlmost equally distributed compression

Tension BandTension Band

Tension Band (Cont’d)Tension Band (Cont’d) Dynamic compressionDynamic compression

When tension appliedWhen tension applied Compressive forces are at the fracture siteCompressive forces are at the fracture site

UsedUsed Substitutes torn ligaments & tendonsSubstitutes torn ligaments & tendons Allows injured ligaments to healAllows injured ligaments to heal When fragments too small to be screwedWhen fragments too small to be screwed

http://www.wheelessonline.com/o2/1536.htm

Tension band & ScrewTension band & Screw

Tension Band & ScrewTension Band & Screw

Plating of Vertebral ColumnPlating of Vertebral Column

Vertebral ColumnVertebral Column

Intramedullary PinIntramedullary Pin

TypesTypes Open Open ClosedClosed

3-point fixation3-point fixation End fixed in epiphysesEnd fixed in epiphyses

Intramedullary Pin (Cont’d)Intramedullary Pin (Cont’d)

Stability is dependant Stability is dependant onon Friction / pressure Friction / pressure

between between Deformable nail (elastic Deformable nail (elastic

recoil)recoil) Endosteal surface of Endosteal surface of

medullary canalmedullary canal Fracture “personality”Fracture “personality”

Intramedullary Pin (Cont’d)Intramedullary Pin (Cont’d)

Blood supply is from the medullary canalBlood supply is from the medullary canalCompromised by intramedullary fixationCompromised by intramedullary fixation

More care has to be takenMore care has to be taken

Open FractureOpen Fracture

Bone ends have penetrated through and Bone ends have penetrated through and outside skinoutside skin

Important featuresImportant features Polytrauma victimsPolytrauma victims Varying soft tissue damageVarying soft tissue damage Contaminated woundContaminated wound Requires emergency treatmentRequires emergency treatment

Types of Open FractureTypes of Open Fracture Type I – Low EnergyType I – Low Energy

Puncture wound (1 cm dia. or lesser)Puncture wound (1 cm dia. or lesser) Not much soft tissue contusionNot much soft tissue contusion Usually simple transverse, short oblique fractureUsually simple transverse, short oblique fracture No crushing componentNo crushing component

Type II Type II Laceration (more than 1 cm long )Laceration (more than 1 cm long ) Not extensive soft tissue damageNot extensive soft tissue damage Not severe crushing componentNot severe crushing component

Type III – High EnergyType III – High Energy Extensive damage to soft tissueExtensive damage to soft tissue High velocity injury or severe crushing componentHigh velocity injury or severe crushing component

Type IType I

Type IIType II

Type IIIType III