2Anatomy The bones that comprise the knee joint: Tibia Fibula Femur PatellaThere are two joints in the knee:Tibiofemoral jointPatellafemoral joint
3AnatomyThe medial and lateral meniscus rest between the femur and tibia.They are responsible for shock absorption, improved bony correlation, joint lubrication, improved weight distribution, and decreased friction.The patella guides the quadriceps, decreases friction during movement, and protects the femoral condyles.
4Anatomy of the Knee Knee is a hinge joint Articulation (point of contact)Consists of 3 bonesStabilized byFour major ligamentsCartilageStrong musculatureKnee is able to rotate
5Cartilage Ends of the tibia and femur Top of tibia End of femur Covered/cushioned byPieces of tough cartilage tissueCalled menisciHelp to stabilize the knee jointWithout bones would rub & wear down quicklyTop of tibiaFlat like a tabletopEnd of femurRounded (called condyles)Without stabilization, femur would move a lot on the tibia
6Cartilage-Menisci Lateral & Medial Thicker on sides Thinner in the middleForm a dish-shaped hollowAttached to the top of the tibiaProvide a seat for the femoral condyles to sit inFemur moves but will not roll off
7Ligaments 4 primary knee ligaments ACL & PCL Medial collateral (MCL) Helps provide stability to inside of kneeLateral collateral (LCL)Helps provide stability to outside of kneeAnterior cruciate ligament (ACL)Keeps tibia from moving forward on the femurPosterior cruciate ligament (PCL)Prevents tibia from moving backward on the femurACL & PCLpass through the middle of the knee jointCross each other (i.e cruciate means “cross-shaped”)
8Ligaments of the Knee Anterior cruciate ligament (ACL) Posterior cruciate ligament (PCL)Medial collateral ligament (MCL)Lateral collateral ligament (LCL)
9Anatomy Muscles of the Knee Quadriceps muscles Responsible for knee extensionHamstring musclesResponsible for knee flexionCalf musclesAssist in knee flexionOther muscles that act at the kneeSartoriusPopliteusPlantarisGracilis
10Muscles of the Knee Provide Primary muscles spanning the knee Movement StabilityPrimary muscles spanning the kneeQuadriceps group (perform knee extension)Vastus medialis, vastus lateralis, vastus intermedius & rectus femorisHamstring group (perform knee flexion)Biceps femoris, semimembranosus & semitendinosusHelp prevent forward movement of the tibia on the femurBy the location of their attachments
12Primary Muscles Spanning the Knee Hamstring groupBiceps femoris, semimembranosus & semitendinosusPerform knee flexionHelp prevent forward movement of the tibia on the femurBy the location of their attachments
13Knee Alignment Concerns Genu valgum (knock-knees)Genu varum (bow legs)Genu recurvatum (hyperextension)Q-angleGreater than 20 increases risk for injuryLeg length discrepancy
14Preventing Knee Injuries Ligament sprainsMost common injuries seen at the kneeMuscles provide stability to the kneeHelp resist abnormal bony movementAthletes should develop strength in the muscles (quads, hams, gastrocnemius/calf, hip abductors & hip adductors)Gastrocnemius-heel raisesSome trainers & athletes use preventative knee bracesDesigned to protect medial collateral ligamentTearing can result from a blow to the lateral side
15Treating Knee Injuries & Conditions Knee is exposed to many forcesMakes it vulnerable to injuriesEspecially the ligamentsTendon & bone injuries also occurPatella & menisci are subject to unique types of athletics-related injuries
16Ligament Injuries Ligament sprains of the knee Can be Mild Moderate Severe
19Patellar Fracture Signs & Symptoms: Pain directly over bone Slight to moderate swellingPain, especially in the first 30º of movementTreatment:Immobilize and refer to a physician for x-raysRequires lengthy immobilization during recovery
20Patellar Dislocation Signs & Symptoms: Moderate to extreme pain Moderate swellingComplete loss of ROM in kneeObvious deformity laterallyTreatment:Refer to physician for reductionRICE therapyProgressive strengthening program
21Patella Dislocation Patella forced to lateral aspect of the knee Often occurs when the knee is bent and forced to twist inwardSigns & symptomsObvious deformityAthlete is often in distressEMS must be calledUnless team physician is presentonly a physician should reduce a dislocated patellaComplications may resultPosterior aspect of patella may be injured further
23Patella-Femoral Stress Syndrome Signs & Symptoms:Pain and tenderness in lateral aspect of patellaSlight swellingCrepitus or popping with extensionTreatment:RICE therapyClosed kinetic chain exercises 0-40
24Patellar Femoral Syndrome Fancy name for a set of symptoms that include pain/discomfort around patellaOften caused by patellar tracking problemsKnee bendsPatella is grated across the femurCausing cartilage on back of patella to soften or wear awayKnown as chondromalacia
25Chondromalacia Signs & Symptoms: Pain underneath the patella Grinding or popping during motionSlight chronic swellingSpecial Tests: Clarke’s SignTreatment:RICE TherapyQuadriceps strengthening
26Patellar Femoral Syndrome Chondromalacia Characterized by achiness around the patellaEspecially with prolonged sitting in the same positionAthlete reports a grinding sensation with flexion/extensionGrinding can be felt by placing hand over knee
28Osgood-Schlatter’s Disease Signs & Symptoms:Pain at insertion of patella tendonTenderness to palpationEnlarged tibial tuberosityPain with jumping or runningTreatment:RICE therapyDecrease activity or cross-train
29Osgood-Schlatter Disorder Irritation at the site of the patellar tendon attachmentTo front of the tibiaCalled tibial turberosityRepeated stress causes the patellar tendon to partially pull away from the boneCalled Osgood-Schlatter’s disorder
30Osgood-Schlatter Disorder Signs & symptomsDiscomfort of the kneeSwellingTendernessPain during activityPossible bump below knee cap (bony growth at the top of the tibia)Can remain even after symptoms have disappearedCareRestrict activity until resolvedStationary bicyclingUse pain as a guideModify activities based on pain level reported by athleteIce before & after activitySpecial pad made to fit over front of tibiaOften improves by age 16 or 17 (but known to last into early 20’s)
31Patellar Tendinitis Signs & Symptoms: Pain in patella tendon or at inferior pole of patellaPain increases with activitySqueaking noise with motionSlight swellingTreatment:Modality treatmentIce or ice massageUltrasound
32Muscle & Tendon Injuries Patellar tendinitisOveruse disorderCharacterized by quadriceps weaknessTenderness over the patellar tendonMinimal swellingCondition is also called jumper's kneeAthletes that do lots of jumping often get this condition (basketball, volleyball)Early stagesAthlete typically has pain after activityTreatmentTrainer attempts to control inflammationApply iceModify athlete’s activity levelRestricting running & jumpingRehabilitation programAddress any flexibility problems or weakness of the leg
33Patella Tendon Rupture Signs & Symptoms:Extreme pain with an immediate drop in painSignificant swellingWindow shade effectComplete loss of knee extensionPrevious history of chronic tendinitisTreatment:Surgical repair is the only treatment option6-8 months minimum recovery
35Knee Dislocation Signs & Symptoms: Immediate pain that may decrease dramaticallyObvious deformity (usually anteriorly)Significant swellingDecreased blood flow and neural sensationTreatment:Splinted and transported to hospital immediatelySurgical intervention is often required for neurovascular and ligament repair
36Knee Contusion Signs & Symptoms: Pain at affected site Moderate swelling and discolorationLoss of ROMDecreased weight bearingTreatment:RICE therapy
37Patella Injuries (Bursitis) Prepatellar bursitis is the inflammation of a small sac of fluid located in front of the kneecap. This inflammation can cause many problems in the knee.
38CausesBursitis is the inflammation of a bursa. The prepatellar bursa can become irritated and inflamed in a number of ways.A direct blow or a fall onto the knee can damage the bursa.
39Meniscus Contusion Signs & Symptoms: Pain, especially at full extensionLoss of ROM in extensionSlight swellingTreatment:RICE therapy
40Meniscus Tears Signs & Symptoms: Pain, especially when moved similarly to the mechanism of injuryPain with full extension or flexionDiffuse swelling in the joint (effusion)Pain along the line of the jointSensation of locking or giving outClicking or popping sound with movement
41Meniscal InjuriesMeniscal injuries damage the cushioning tissue between the tibia and the femur, inside the knee joint, on both sides (medial and lateral) of the knee.
42CausesThey are highly vulnerable to injury from abrupt rotations of the knee while it is bearing weight, for example, when you turn to hit a tennis ball, rotating your thigh (femur) while leaving your foot stationary.
48Meniscus Tears Special Tests: McMurray’s Test Apley’s Compression Test Bounce Home TestTreatment:Referral to a physicianSurgery is often required for full recovery.RTP depends on surgical option selected.
49ACL Sprain Signs & Symptoms: Pain in the joint Athlete hears ‘pop’ at time of injurySense of looseness in joint, giving away, or shiftingSwelling that increases rapidly post-injury
50Anterior Cruciate Ligament Injuries Keeps tibia from moving forward on the femurIf ligament is injuredAthlete is often disabledComplaining of the knee “giving away”, collapsing & poppingMost serious of all knee ligament injuriesMost frequently surgically reconstructed
51Anterior Cruciate Ligament Injuries Often injured as the athlete is attempting to change directions quicklyTwists the lower legMay hear a popping sound during the twistingAlso injured during excessive hyperextension
52Anterior Cruciate Ligament Injuries Signs & symptomsRapid swellingLoss of knee functionImmediate treatmentPRICEKnee immobilizerCrutchesFollow up with an orthopedist is necessaryAthlete rarely can continue a high level of function with a torn ACL
53Anterior Cruciate Ligament Injuries Often needs to be surgically reconstructedDetermination that must be made by the athlete, surgeon & athlete’s familyDepends on the amount of instability that existsLevel of function desired by the athleteAge of the athlete
64Anterior Cruciate Ligament Injuries Rehabilitation Focuses on strengthening the hamstringsHelps stabilize the tibiaHelps regain full functionEven with aggressive ACL rehabMay be six months before athlete can return to participation
65ACL Sprain, cont. Special Tests: Anterior Drawer Test Lachman’s Test Pivot Shift TestTreatment:Grade 1 or 2 may be treated conservatively.Grade 3 tear will require surgery.
66PCL Sprain Signs & Symptoms: Pain in posterior aspect of knee Slight swellingJoint laxityLoose feeling with walkingSpecial Tests:Posterior Sag TestPosterior Drawer TestTreatment:Grade 1 or 2 may be treated conservativelyGrade 3 tear will require surgery
67Posterior Cruciate Ligament Injuries Prevents posterior tibial movement on the femurFrequently injured whenathlete falls and a bent knee bears full weightKnee is forcefully hyperflexedBlow delivered to the front of the tibia
70Posterior Cruciate Ligament Injuries AssessmentTrainer determines mechanism of injuryAthlete reports having heard a popOften little swelling with PCL injuryInitial treatmentPRICEReferral to a physician
71Posterior Cruciate Ligament Injuries Physicians disagree about whether or not surgery should be performed on a severe PCL injuryEven complete PCL tears can be rehabilitated without surgeryRehabilitation programs for mild/moderate PCL sprainsFocus on strengthening the quadricepsRegaining full functionMany athletes can become functional againAfter initial pain & swelling are controlledAfter knee is strengthened
72MCL Sprain Signs & Symptoms: Pain increasing with severity Joint stiffnessSlight to moderate swellingDecreased ROMJoint laxity medially
73Medial Collateral Ligament Sprains Frequently injured when an athlete receives a blow to the outside of the kneeCauses knee to bend inward (valgus stress)Stresses the MCLMild sprainMedial joint line painLittle if any swellingNo joint laxity when stressed by trainer during assessmentFull knee flexion & extension
74Medial Collateral Ligament Sprains Moderate MCL sprainMild swellingDiscomfortSome joint laxity when stressed by the trainer during assessmentSevere MCL injuryModerate or severe amount of swellingLoss of functionGreat deal of joint laxity when stressed by the trainer during assessment
75Medial Collateral Ligament Sprains Treated with PRICEMild injuryElastic wrap for compression/supportModerate/severe injuryKnee put in an immobilizerTrainer should consider possibility of damage to the menisci or an ACL injuryRehabilitationFocuses on strengthening the muscles that cross the medial aspect of the knee
76MCL Sprain, Cont. Special Tests: Valgus Stress Test Apley’s Distraction TestTreatment:RICE TherapyImmobilizationProgressive strengthening program
77LCL Sprain Signs & Symptoms: Pain over lateral aspect of knee Slight to moderate swellingJoint laxity laterallyJoint stiffnessDecreased ROM
78Lateral Collateral Ligament Injuries Occur less frequently than MCL injuriesSigns & symptoms are similar to MCLExcept discomfort is at the lateral aspect of the kneeTreatmentSame as MCLRehabilitation (regaining joint stability)Strengthening exercises focus on the lateral thigh muscles & hamstrings
79LCL Sprain, cont. Special Tests: Varus Stress Test Apley’s Distraction TestTreatment:RICE TherapyImmobilizationProgressive strengthening program
80Discussion QuestionsWhat would be your response to an athlete who wants to play with an ACL tear?How would you react on the field if an athlete dislocated their knee?