Presentation on theme: "Injuries to the Tissues"— Presentation transcript:
1 Injuries to the Tissues Chapter 14Injuries to the Tissues
2 OA 10.21Differentiate between a primary injury and secondary injury
3 ObjectivesIntroduce the terminology associated with injury classificationIntroduce biomechanical forces that cause injuriesExplain biomechanical concepts for various tissues
4 Injury classification IntrinsicInfection (viral, bacterial)ExtrinsicTissue stressed to the point of mechanical failure due to excessive force
5 Extrinsic injury classification Primary InjuryDirect immediate consequence of excessive force (trauma)Secondary InjuryDelayed injury some time after initial traumaAn accommodation to the primary injury
6 Extrinsic injury classification Acute InjuryMechanical failure of soft tissue due to excessive force occurring in a single boutSudden onset of short duration
7 Extrinsic injury classification Chronic InjuryMechanical failure of soft tissue due to repeated micro-trauma occurring over an extended period of timeGradual onset and are of prolonged duration
8 Injury classification MicrotraumaOccurs with repeated submaximal forces over time, and the tissues are unable to adaptMacrotraumaOccurs when a single force exceeds the tissue’s failure point
9 Open vs. closed Open Closed Exposed Breaks the surface of the skin UnexposedAny injury that does not involve disruption of the skin surface
10 Mechanical stresses Load/Stress Deformation/Strain External/internal force acting on the tissueForce = Mass x Acceleration (F=ma)Deformation/StrainExtent of deformation under loading
11 load/deformation Mechanical force causes deformation Degree of deformation depends on:Tissue compositionSpeed of applied loadFrequency of loadingDirection of loadingDeformationLoad
12 Yield point Load is greater than mechanical capabilities of the tissue Elastic limit of the tissue has been reachedMechanical failure occursUltimateFailurePointLoadYieldPointElasticRegionPlasticRegionDeformation
13 Tissue stresses Five primary mechanical forces that cause injury TensionCompressionBendingShearTorsion
14 Tissue stresses Can occur alone or in combination Type of force = Mechanism of Injury (MOI)
15 tension Creates a pulling action trying to elongate the structure Longitudinal “tearing” stressOverstretched tissue (i.e. valgus force)
50 Chain of infection pathogen RESERVOIR HOST PORTAL OF EXIT Infected individualPORTAL OF EXITNose, mouth, eyes, urinary/reproductive system, open woundsROUTE OF TRANSMISSIONDirect or indirect contactPORTAL OF ENTRYSUSCEPTIBLE HOSTVery young and elderly are most susceptiblepathogen
51 Universal Precautions Those in direct contact must use protective equipmentNon-latex gloves, gowns, aprons, masks & face shield, eye protection, CPR barriersEmergency kits should include gloves, CPR barrier, alcohol prep pads at minimum
52 Universal Precautions Doubling gloves is suggested with severe bleeding
53 Universal precautions Use Personal PrecautionsExtreme care must be used with glove removalGlove Removal
54 Universal precautions Use Personal PrecautionsWash hand & skin surfacesProper Hand Washing
55 Supplies to have on hand Non-latex glovesSterile 4”x4” gauze pads/spongesSterile saline solutionNon-adherent padsAntiseptic/antibiotic ointmentNon-adherent cohesive tapeOptional: soap, water, hand sanitizer, hydrogen peroxide, cinder suds, nitrotan
56 bleeding 3 types of external bleeding Venous – dark red blood, slowly flowingCapillary – bright red, seeping/oozingArterial – bright red, spurts or streams
57 Controlling bleedingFor all types of bleeding direct pressure must be applied to the areaBlood takes 4-6 minutes to clot
58 Controlling bleedingUse a sterile gauze pad/compress to collect the bloodIf saturated, add additional gauze as neededNever remove and replace, always add!
59 Controlling bleeding Arterial bleeding is a medical emergency Direct pressure must be applied until EMS arrivesElevation can help slow blood lossBody part placed above level of the heartExceptions: fractures & spinal injuries
60 Controlling bleeding Indirect pressure can slow blood loss Pressure points proximal to the injury must be compressed
62 Wound cleansingDebridement - removal of dead, damaged, or infected tissue to improve the healing potential of the remaining healthy tissue.
63 Wound cleansingCleansing and debriding a wound prevents infections and increases healing time.
64 OA 10.23List in order the four methods for controlling bleeding.
65 Wound cleansingRemove any dirty bandages, clothing, etc. from the woundApply a solution to irrigate the woundSaline, sterile water, etc.Clean the wound with circular motion starting at the center and working outwardsIrrigate the wound once more to remove all dirt & debrisDry the area with sterile gauzeCover the wound with a sterile dressing
67 Applying bandages & dressings Dressing = contact with the woundBandage = holds dressing in place
68 Applying bandages & dressings Bandages and dressings decrease the risk of infection if properly applied and maintainedMust cover the wound entirely and stay in placeAllow for normal movement and activityAbsorb blood and drainageProtect the wound from further injury
75 Wound care management Patient instructions Keep wound clean and dry Change dressings dailyRemove and replace if wetWatch circulation of the limb; seek medical help if circulation is impairedWatch for signs of infection
76 Signs of infection Redness Swelling Increased pain Red streak up the arm or legFoul-smelling odorElevation in temperature over the wound or surrounding tissue
81 Five Major Functions Of The Skeleton Protection of vital soft tissuesSupport human postureMovement by serving as points of attachment for musclesStorage for mineralsHemopoiesis – the process of blood formation that occurs in the red bone marrow
82 Mechanical properties of bone Wolff’s Law: bone will adapt to the loads under which it is placed.
83 Mechanical properties of bone Direction of LoadingStrongest in compressionWeak in tensionWeakest in shearCompression > Tension > Shear
84 Mechanical properties of bone Bone size↑ size of bone (mass) = ↑ bone strengthGreater area to distribute mechanical stresses
85 Mechanical properties of bone Bone shapeSudden shape changes are areas where mechanical stresses are most concentratedWeak points/Stress risers
86 Bone growth Epiphyseal growth plate Cartilaginous disk near the end of each long boneDependent on plateInjury can prematurely close the plate causing loss of length
87 Mechanisms of bone injuries Pure tensile forcesCompression forcesBending
88 Three-point bending ↑ distance from center = ↑ bending moment Tensile ForceCompressive Force
91 Bone injuries Periostitis Bone contusion Inflammation of the periosteum, usually from contusionBone contusionBruising of the bone tissueVery painfulSlow to heal – typically 6-8 weeks
92 Live InjuriesProper Field Set-UpFemurACLKneeBroken Leg
93 OA 10.28Describe the properties of bone that make it strongest, weakest, and most prone to injury.
94 Bone injuries Fracture Any disruption in the continuity of the bone or periosteum
95 Bone injuries Description of Fracture Site Extent – partial, complete, hairlineConfiguration - typeRelationship of fragments – displaced, non-displacedRelationship to external environment – closed, compound
100 Bone trauma classification TypeEtiologyTransverseDirect BlowSpiralRotation on planted footObliqueOne end fixed, other sudden torsionComminutedBlow or fall in awkward positionDepressedFlat bones, direct blow
101 Bone trauma classification TypeEtiologyGreenstickIncomplete Fx, skeletally immature (convex)LongitudinalSplits along length, jumping from heightSerratedDirect blow, jagged edgesContrecoupSide opposite to point of impactImpactedCompressive force on long axis of bone
117 Stress Fractures Also called march, fatigue, & spontaneous fractures Weight bearing bones become weaker before they become stronger
118 Stress Fractures Typical causes in sports: Coming back too soon after injury or illnessChanging events without proper trainingStarting initial training too quicklyChanging habits or the environment
122 Joints (Articulations) All joints are comprised of capsular tissue surrounding the joint itselfStrong, fibrous tissueSynovial jointsCapsular tissueArticular cartilage at ends of bonesSynovial membrane & fluidMuscles affecting the joint
123 Synovial Joints Synovial Membrane & Fluid Membrane made of connective tissue for articular capsuleFluid is secreted & absorbed in membrane; acts as lubricant
124 Synovial Joints Articular Cartilage Connective tissue providing supportHyaline (nasal septum), fibrous (vertebral disks & menisci), & elastic (ear)Aids in motion control, stability, and load transmission for joints
138 Bursitis Fluid filled sac in places where friction occurs Between bony prominences and tendons
139 Tendons and Ligaments Functions Inert Structures Tendons Ligaments Execute joint motion by transmitting mechanical forces from muscles to bonesLigamentsJoin bones and provide stability to jointsInert StructuresNon-contractile structures (passive tissues)Unable to actively generate forces
140 Mechanical Properties of Tendon Composed of mostly collagen fibersHigh resistance to tensile forcesLocationStrongest in mid-pointWeakest at myo-tendinous and osteo-tendinous junctionsDue to changes in tissue composition
141 Tendon Injuries Tendinitis – inflammation of the tendon Chronic injury due to repetitive motion or overuseAppears as dull, aching pain before/during/after exerciseOccurs with crepitus
142 Tendon Injuries Tenosynovitis – inflammation of the synovial sheath More severe form of “-itis” injury
143 Tendon Injuries Strain / Rupture – overload of the tendinous junction Contusion
144 Tendon Injury Attaches muscle to bone Usually double the strength of the muscle it servesAcute strainTendonitis
145 Mechanisms of Tendon Injuries High magnitude, single load, tensile forcesAcute strain or ruptureLow magnitude, repetitive load, tensile forcesTendinitis or tenosynovitisDynamite vs. Axe
146 Mechanical Properties of Ligaments Greater proportion of elastic collagen fibers than in tendonLess resistant to tensile forcesGreater deformation occurs prior to mechanical failure
147 Mechanical Properties of Ligaments Frequency of LoadingRepeated loading Mechanical Weakening instabilityDirection of LoadingResists tensile forces
148 Mechanisms of Ligament Injuries High magnitude, single load, tensile forcesAcute sprain or ruptureLow magnitude, repetitive load, tensile forcesConstant tensile forces lead to ligamentous deteriorationChronic instability
150 Grades of Ligamentous Injury DegreeEtiologyEnd FeelInstabilityFirstMild overstretching, no tissue disruptionFirmNoneSecondPartial disruption or macrotearing of the ligamentDefinite (soft)Slight to ModerateThirdComplete disruptionSevere
151 Skeletal Muscle Composed of contractile cells Function Generates force to drive motionDynamic stability of joints
152 Skeletal Muscle Tensile Forces Produces active and passive tensile forcesActive tension contractionPassive tension stretched past resting length
153 Skeletal Muscle Injuries StrainsContusionsMuscle lacerationsMyositisAtrophyContractureDOMSSpasmContractureShortening of the muscle
154 Muscle Injury Acute Contusions Sudden traumatic blow with compressive forceSuperficial or deep tissue affectedRated by the ability of muscle to produce ROM
155 Muscle Injury Acute Strains Stretch or tear in muscle Abnormal muscle contractionMineral imbalance or dehydrationFatigueStrength imbalance
156 Muscle Injury Acute Muscle spams (cramps) Clonic - intermittent Tonic – constantContractureMay lead to strainsDOMS
157 Muscle Injury Chronic Myositis Fasciitis Myositis ossificans Inflammation of muscleFasciitisInflammation of fascia within the muscleMyositis ossificansRepeat traumaCalcium deposits within the muscleCan resorb in 9-12 months
158 Mechanisms of Muscle Injuries High magnitude, single load, tensile forcesAcute strains or rupturesLow magnitude, repetitive load, tensile forcesDegenerative effectDynamite vs. Axe
159 Grades of Muscle Injuries DegreeEtiologySigns/SymptomsFirstOverstretching or microtearing of muscle or tendonMild loss of strength, swelling, ecchymosis, point tendernessSecondFurther stretching and partial tearing of muscle or tendon fibersSymptoms are more severe, greater function lossThirdComplete ruptureSevere symptoms, loss of muscle function, possible palpable defect
160 Nerve Injuries Compression or tensioning of neural structure Secondary to direct blowAcute swelling in enclosed spacePathology which compromises space for nerveAnesthesiano sensationParesthesiatingling, burning, numbnessHyperesthesiahypersensitivity
162 Neuropraxia “Burners” or “stingers” Transient and reversible loss in nerve functionSecondary to trauma or irritationMechanical deformation of the nerveDisruption of nerve fibers & signalsShort-lived sensory and motor deficits (seconds-two weeks)
163 A shortstop is hit in the shin by a batted ball that took a bad hop What kind of force is involved?What type of injury is likely to have occurred?
164 A football player sustains repeated blows to his left quadriceps muscle What type of injury could be sustained from repeated compressive forces to the muscle?
165 A basketball player steps on another player’s foot and sustains a lateral ankle injury What forces are applied?What type of injury has occurred?
166 An alpine skier catches his right ski tip and severely twists the lower leg What type of serious injury could be created by this mechanism?