This document discusses common knee injuries, including acute injuries like ACL tears, meniscal tears, and patellar dislocations, as well as overuse injuries. It provides details on mechanisms of injury, symptoms, physical exam findings, imaging, treatment including RICE protocol and possible surgery, and prognosis. Knee injuries are common due to the knee's role in weight bearing and lack of bony and muscular support, making it prone to ligament tears and cartilage damage from sudden movements or repetitive stress.

1. FahadFahad
zakwanzakwan
MD5MD5

2. one of the most commonly injuredone of the most commonly injured
jointsjoints
lack of bony and muscular supportlack of bony and muscular support
positioned between the 2 longestpositioned between the 2 longest
bonesbones
weight bearing and locomotionweight bearing and locomotion
functionsfunctions

3. 1.1. ACUTE KNEEACUTE KNEE
INJURIESINJURIES
2.2. OVERUSE KNEEOVERUSE KNEE
INJURIESINJURIES

4. ACUTE KNEE INJURIESACUTE KNEE INJURIES
1.1. Anterior cruciate ligament (ACL) injuryAnterior cruciate ligament (ACL) injury
2.2. Posterior cruciate ligament (PCL)injuryPosterior cruciate ligament (PCL)injury
3.3. Medial Collateral ligament (MCL) InjuryMedial Collateral ligament (MCL) Injury
4.4. Lateral collateral ligament (LCL) injuryLateral collateral ligament (LCL) injury
5.5. Meniscal injuriesMeniscal injuries
6.6. OSTEOCHONDRAL PROBLEMSOSTEOCHONDRAL PROBLEMS
7.7. Patellar dislocation/instabilityPatellar dislocation/instability

5. 1. Anterior cruciate ligament (ACL)1. Anterior cruciate ligament (ACL)
injuryinjury
Most are non-contactMost are non-contact
injury, 2injury, 2° to° to
deceleration forces ordeceleration forces or
hyperextensionhyperextension
Planted foot & sharplyPlanted foot & sharply
rotatingrotating
If 2° to contact, mayIf 2° to contact, may
have associated injuryhave associated injury
(MCL, meniscus)(MCL, meniscus)

8. FemalesFemales playingplaying soccersoccer,, gymnasticsgymnastics andand
basketballbasketball are at highest riskare at highest risk
Risk of injuryRisk of injury 2 – 8 times2 – 8 times in women↑ in women↑
~250,000 injuries/year in general population~250,000 injuries/year in general population
Gender difference not clearGender difference not clear
Joint laxity, limb alignmentJoint laxity, limb alignment
Neuromuscular activationNeuromuscular activation

9. HxHx::
Hearing or feeling a “pop” & knee gives wayHearing or feeling a “pop” & knee gives way
Significant swelling quickly (< 1 hour)Significant swelling quickly (< 1 hour)
UnstableUnstable
↓↓ range of motion (ROM)range of motion (ROM)
Achy, sharp pain with movementAchy, sharp pain with movement

10. PEPE::
Large effusion,Large effusion, ROM↓ ROM↓
Difficult to bear weightDifficult to bear weight
Positive anterior drawerPositive anterior drawer
Positive Lachman’sPositive Lachman’s

11. Imaging:Imaging:
X-rayX-ray
alwaysalways
MRIMRI
The left ACL has beenThe left ACL has been
torn for over 10 yrs. whiletorn for over 10 yrs. while
the right knee had an ATLthe right knee had an ATL
tear just for one monthtear just for one month

12. MRI

13. TreatmentTreatment::
RICERICE
Hinged knee braceHinged knee brace
CrutchesCrutches
Pain medicationPain medication
RehabilitationRehabilitation
Avoid most activitiesAvoid most activities
(stationary bike o.k.)(stationary bike o.k.)
Surgery (in most cases)Surgery (in most cases)
RICERICE
•RESTREST: reduce/stop using injured: reduce/stop using injured
area for at least 48hrs. If you havearea for at least 48hrs. If you have
leg injury, you may need to stay offleg injury, you may need to stay off
of it completely.of it completely.
•ICEICE: put an ice pack on the injured: put an ice pack on the injured
area for 20 min at a time, 4-8× a day.area for 20 min at a time, 4-8× a day.
•COMPRESSIONCOMPRESSION: compression of: compression of
an injured ankle may help to reducean injured ankle may help to reduce
swelling. These include bandagesswelling. These include bandages
such as elastic wraps or splints.such as elastic wraps or splints.
•ELEVATIONELEVATION: keep the injured: keep the injured
area elevated above the level of thearea elevated above the level of the
heart.heart.

14. PrognosisPrognosis::
Usually an isolated injuryUsually an isolated injury
Post-op: 8-12 months until full activityPost-op: 8-12 months until full activity
ReferralReferral::
Almost all young, athletic patients will preferAlmost all young, athletic patients will prefer
surgical reconstructionsurgical reconstruction
?Increased risk of DJD if not treated?Increased risk of DJD if not treated
Can still get DJD if reconstructedCan still get DJD if reconstructed

15. Posterior cruciate ligamentPosterior cruciate ligament
(PCL)injury(PCL)injury
MxnMxn::
hyperflexionhyperflexion
falling on bent knee with foot plantar flexedfalling on bent knee with foot plantar flexed
Hit on fixed anterior tibiaHit on fixed anterior tibia
S/S:S/S:
““pop” at the back of kneepop” at the back of knee
swelling in popliteal fossaswelling in popliteal fossa
+ posterior sag test, +sunrise test, + posterior+ posterior sag test, +sunrise test, + posterior
drawer testdrawer test

16. TxTx::
RICERICE
ImmobilizationImmobilization
CrutchesCrutches
Physician referralPhysician referral
6-8 weeks rest/rehab6-8 weeks rest/rehab
If surgery is elected, 6 weeks immobilizationIf surgery is elected, 6 weeks immobilization

18. Stress testsStress tests
Posterior sagPosterior sag

19. Strest tests
Sunrise orSunrise or
posterior sagposterior sag

20. 3. Medial Collateral ligament (MCL)3. Medial Collateral ligament (MCL)
InjuryInjury
Important in resistingImportant in resisting
valgus movementvalgus movement
Common in contactCommon in contact
sports, i.e. football,sports, i.e. football,
soccersoccer
Hit on outside of kneeHit on outside of knee
while foot plantedwhile foot planted
Associated injuriesAssociated injuries
common, depending oncommon, depending on
severityseverity

21. HxHx::
Immediate pain over medial kneeImmediate pain over medial knee
Worse with flexion/extension of kneeWorse with flexion/extension of knee
Pain may be constant or present withPain may be constant or present with
movement onlymovement only
Knee feels ‘unstable’Knee feels ‘unstable’
Soft tissue swelling, bruisingSoft tissue swelling, bruising

22. PEPE::
no effusionno effusion
medial swellingmedial swelling
pain with flexionpain with flexion
tender over medialtender over medial
femoral condyle,femoral condyle,
proximal tibiaproximal tibia
Valgus stress at 0Valgus stress at 0° &° &
30° PAIN, possible→30° PAIN, possible→
laxitylaxity

23. ImagingImaging::
obtain radiographs to r/o fractureobtain radiographs to r/o fracture
MRI if other structures involved or if unsure ofMRI if other structures involved or if unsure of
diagnosisdiagnosis

24.  TreatmentTreatment: Grade I: Grade I no laxity @ 0°or 30°→no laxity @ 0°or 30°→
Grade IIGrade II no laxity @ 0°,but→no laxity @ 0°,but→
lax @ 30°lax @ 30°
 RICERICE
 Hinged-knee brace (Grade II)Hinged-knee brace (Grade II)
 CrutchesCrutches
 Aggressive rehabilitationAggressive rehabilitation
 NSAIDsNSAIDs
 Treatment:Treatment: Grade IIIGrade III lax @ 0° & 30°→ lax @ 0° & 30°→
 Same as aboveSame as above
 Consider Orthopedic referralConsider Orthopedic referral

25. PrognosisPrognosis::
Grade I -- 10 daysGrade I -- 10 days
Grade II -- 3-4 weeksGrade II -- 3-4 weeks
Grade III -- 6-8 weeksGrade III -- 6-8 weeks
When to refer:When to refer:
Other ligamentous injuries (surgical)Other ligamentous injuries (surgical)
Severe MCL injurySevere MCL injury
Not progressing as expectedNot progressing as expected

26. ComplicationsComplications
The terrible triad or unhappy triadThe terrible triad or unhappy triad
Torn ACLTorn ACL
Torn MCLTorn MCL
Torn Medial meniscusTorn Medial meniscus

27. 4. Lateral collateral ligament4. Lateral collateral ligament
(LCL) injury(LCL) injury
MxnMxn::
Varus force to medial aspect of kneeVarus force to medial aspect of knee
internal rotation of tibiainternal rotation of tibia
S/SS/S::
POT over LCL,POT over LCL,
pain,pain,
swelling,swelling,
loss of motion,loss of motion,
““+” varus stress at 30 degrees—solid endpoint with 1+” varus stress at 30 degrees—solid endpoint with 1stst
degree, lessdegree, less
stability but solid endpoint with 2stability but solid endpoint with 2ndnd
degree, no endpoint with 3degree, no endpoint with 3rdrd
degreedegree
if “+” varus stress at 0 degrees flexion suspect ACL or PCL injury asif “+” varus stress at 0 degrees flexion suspect ACL or PCL injury as
wellwell

28. Tx:Tx:
RICERICE
CrutchesCrutches
Knee immobilizerKnee immobilizer
Physician referral with 2Physician referral with 2ndnd
or 3or 3rdrd
degreedegree

29. 5. Meniscal injuries5. Meniscal injuries
Meniscus = ‘little moon’Meniscus = ‘little moon’
in greekin greek
Absorbs shock,Absorbs shock,
distributes load,distributes load,
stabilizes jointstabilizes joint
Thick at peripheryThick at periphery →→
thin centrallythin centrally
Lateral Medial

30. CausesCauses::
Sudden twistingSudden twisting
Young athletesYoung athletes
Simple movementsSimple movements
Older kneeOlder knee

31. Hx:Hx:
Clicking, catching or lockingClicking, catching or locking
Worse with activityWorse with activity
Tends to be sharp pain at jointTends to be sharp pain at joint
lineline
EffusionEffusion

32. PEPE::
mild-moderatemild-moderate
effusioneffusion
pain with fullpain with full
flexionflexion
tender at joint linetender at joint line
+ McMurray’s+ McMurray’s
McMurray’s Test

33. Imaging:
MRI

34. TreatmentTreatment::
RICERICE
Surgical repair orSurgical repair or
excision (arthroscopic)excision (arthroscopic)
CrutchesCrutches
NSAIDsNSAIDs
Knee sleeveKnee sleeve
Asymptomatic tears doAsymptomatic tears do
not require treatmentnot require treatment

35. PrognosisPrognosis::
Results of surgical repair/excision areResults of surgical repair/excision are
very goodvery good
Return to full activities 2-4 months afterReturn to full activities 2-4 months after
surgery; tends to be quicker for athletessurgery; tends to be quicker for athletes
When to refer:When to refer:
Most symptomatic meniscal injuriesMost symptomatic meniscal injuries
require surgeryrequire surgery

36. 7. Patellar7. Patellar
dislocation/instabilitydislocation/instability
Patella may dislocate or sublux laterallyPatella may dislocate or sublux laterally
Young, active patients at highest risk (~agesYoung, active patients at highest risk (~ages
13-20)13-20)
Common in football & basketballCommon in football & basketball
♀♀ > ♂> ♂
Recurrence is common, especially if firstRecurrence is common, especially if first
dislocation < 15 yodislocation < 15 yo

37. Indirect traumaIndirect trauma
most commonmost common
mechanismmechanism
Strong quadStrong quad
contraction while legcontraction while leg
is in valgus and footis in valgus and foot
plantedplanted
Other knee ligamentOther knee ligament
injuries can occurinjuries can occur

38. Risk factors:Risk factors:
TraumaTrauma
Pes planusPes planus
Genu valgumGenu valgum
Weak VMOWeak VMO

39. Hx:Hx:
Feel a ‘pop’ and immediate painFeel a ‘pop’ and immediate pain
Obvious knee deformityObvious knee deformity
Painful, difficult to bend kneePainful, difficult to bend knee
May spontaneously relocate, leftMay spontaneously relocate, left
with feelings of instabilitywith feelings of instability

40. dislocation

41. PEPE::
LaterallyLaterally
shifted patellashifted patella
PatellarPatellar
apprehensionapprehension
SwellingSwelling

42. ImagingImaging::
Standard knee x-Standard knee x-
rays a good startrays a good start
Likely need an MRILikely need an MRI
if injury seemsif injury seems
significant orsignificant or
associated injuriesassociated injuries
seem possibleseem possible
MRI

43. Treatment:Treatment:
NSAIDSNSAIDS
IceIce
Patellofemoral kneePatellofemoral knee
brace/rigid bracebrace/rigid brace
PTPT
ROM quickly (~ 2week)ROM quickly (~ 2week)
Quad strengtheningQuad strengthening
Elec. StimElec. Stim
SurgerySurgery
Recurrent instabilityRecurrent instability

44. PrognosisPrognosis
Recurrent instability is common, butRecurrent instability is common, but
rehab is mainstay and very usefulrehab is mainstay and very useful
When to referWhen to refer
Associated fractureAssociated fracture
Poor response to rehabPoor response to rehab
Multiple dislocations (#?) & skill levelMultiple dislocations (#?) & skill level

45. Patella fracturePatella fracture
MxnMxn::
direct impact or trauma to patelladirect impact or trauma to patella
Indirect trauma in which a severe pull of the patellar tendon occursIndirect trauma in which a severe pull of the patellar tendon occurs
against the femur when the knee if semi-flexedagainst the femur when the knee if semi-flexed
S/SS/S::
hemorrhage which results in significant swellinghemorrhage which results in significant swelling
painpain
POT over PatellaPOT over Patella
extreme pain with weight bearing/movementextreme pain with weight bearing/movement

46. Patella Fracture

47. Tx:Tx:
RICERICE
ImmobilizeImmobilize
CrutchesCrutches
Possible surgery depending on type ofPossible surgery depending on type of
fracturefracture

48. OVERUSE KNEEOVERUSE KNEE
INJURIESINJURIES
1. Iliotibial band tendonitis1. Iliotibial band tendonitis
2. Popliteus tendinitis2. Popliteus tendinitis
3. Patellofemoral pain syndrome3. Patellofemoral pain syndrome
4. Patellofemoral synovial plica4. Patellofemoral synovial plica
5. Infrapatellar fat pad syndrome5. Infrapatellar fat pad syndrome
6. Patellar tendonitis6. Patellar tendonitis
7. Bursitis7. Bursitis

49. 1. Iliotibial band tendonitis1. Iliotibial band tendonitis
Excessive frictionExcessive friction
between iliotibial bandbetween iliotibial band
(ITB) & lateral femoral(ITB) & lateral femoral
condylecondyle

50. Iliotibial band tendonitis
Common in runnersCommon in runners
and cyclistsand cyclists
foot pronation, genufoot pronation, genu
varum are riskvarum are risk
factorsfactors

51. HxHx::
Pain at lateral kneePain at lateral knee
At first, sxs only after a certainAt first, sxs only after a certain
period of activityperiod of activity
Progresses to pain immediatelyProgresses to pain immediately
with activitywith activity

52. PE:PE:
Tender at lateralTender at lateral
femoralfemoral
epicondyle, ~3cmepicondyle, ~3cm
proximal to jointproximal to joint
lineline
Soft tissueSoft tissue
swelling & crepitusswelling & crepitus
No joint effusionNo joint effusion

53. PE:PE:
Ober’s testOber’s test
Noble’s testNoble’s test
Noble’s test

54. Iliotibial band tendonitis
Tx:Tx:
Relative restRelative rest
IceIce
NSAIDSNSAIDS
StretchingStretching
CortisoneCortisone
Platelet-RichPlatelet-Rich
PlasmaPlasma

55. Iliotibial band tendonitis
Prognosis:Prognosis:
Improves with restImproves with rest
Expect long recovery timeExpect long recovery time
When to refer:When to refer:
Intractable painIntractable pain
Surgery = releaseSurgery = release

56. 2. Popliteus tendinitis2. Popliteus tendinitis
surrounds posterolateral aspect ofsurrounds posterolateral aspect of
knee, stabilizer in flexion by resistingknee, stabilizer in flexion by resisting
forward displacement of the femur onforward displacement of the femur on
the tibiathe tibia
less common but same causes as itbless common but same causes as itb
(d/d)(d/d)

57. discomfort on anterior or superiordiscomfort on anterior or superior
lat.collateral ligament and withlat.collateral ligament and with
resisted knee flexion with tibia held inresisted knee flexion with tibia held in
external rotationexternal rotation
- treatment: reduction training- treatment: reduction training
distance, NSAIDS, stretching kneedistance, NSAIDS, stretching knee
flexors, electrotherapy. corticosteroidflexors, electrotherapy. corticosteroid
injectioninjection

58. 3. Patellofemoral pain3. Patellofemoral pain
syndromesyndrome
Retropatellar orRetropatellar or
peripatellar painperipatellar pain
resulting from physicalresulting from physical
or biomechanicalor biomechanical
changes in thechanges in the
patellofemoral jointpatellofemoral joint
Many forces interact toMany forces interact to
keep the patella alignedkeep the patella aligned

59. Patellofemoral pain syndrome
Patella not onlyPatella not only
moves up and down,moves up and down,
but rotates and tiltsbut rotates and tilts
Many points ofMany points of
contact betweencontact between
patella and femoralpatella and femoral
structuresstructures

60. Patellofemoral pain syndrome
Hx:Hx:
Vague anterior knee pain with insidious onsetVague anterior knee pain with insidious onset
Common cause of anterior knee pain in womenCommon cause of anterior knee pain in women
Tend to point to front of knee when asked toTend to point to front of knee when asked to
localize painlocalize pain
Worse with certain activities, i.e. ascending orWorse with certain activities, i.e. ascending or
descending hills & stairsdescending hills & stairs
Pain with prolonged sittingPain with prolonged sitting theater sign→ theater sign→
No meniscal or ligamentous sxsNo meniscal or ligamentous sxs

61. Patellofemoral pain syndrome
PE:PE:
Positive compression testPositive compression test
Patellar crepitus with ROMPatellar crepitus with ROM
Mild effusion possibleMild effusion possible
May see tenderness withMay see tenderness with
patella facet palpationpatella facet palpation →→
medial, lateral, superior,medial, lateral, superior,
inferiorinferior
Remainder of knee examRemainder of knee exam
unremarkableunremarkable

62. Patellofemoral pain syndrome
PE:PE:
CheckCheck
hamstringhamstring
flexibilityflexibility

63. Patellofemoral pain syndrome
PE:PE:
Check for flat feet (pes planus) or high-arch feet (pesCheck for flat feet (pes planus) or high-arch feet (pes
cavus)cavus)
Pes Planus Pes Cavus

64. Patellofemoral pain syndrome
PE:PE:
Check heel cord (achilles) flexibilityCheck heel cord (achilles) flexibility
Check for a tight iliotibial band (ober’s test)Check for a tight iliotibial band (ober’s test)
Ober’s test
Achilles stretch

65. Patellofemoral pain syndrome
Tx:Tx:
Physical therapyPhysical therapy
Improve flexibilityImprove flexibility
Quad strengthening,Quad strengthening,
especially VMOespecially VMO
Other modalities, i.e.Other modalities, i.e.
soft tissue release, U/Ssoft tissue release, U/S
Patellar tapingPatellar taping

66. Patellofemoral pain syndrome
Tx:Tx:
Relative rest/ModificationRelative rest/Modification
of activitiesof activities
IcingIcing
NSAIDSNSAIDS
Patellar bracesPatellar braces
Addressing foot problemsAddressing foot problems
with foot wear andwith foot wear and
orthoticsorthotics
SurgerySurgery

67. 4. Patellofemoral synovial4. Patellofemoral synovial
plicaplica
- REMNANTS OF THE SEPTA OF EMBRYONIC JOINT. USUALLY
PRESENT BUT ASYMPTOMATIC
- SYMTOMATIC PLICA: MEDIAL PATELLAR PLICA RUNS FROM
SUPRAPATELLAR POUCH TO THE INFRAPATELLAR FAT PAD
MAY IMPINGE OF THE MEDIAL FEMORAL CONDYLE AND PFJ
IN FLEXION

68. 4) PF SYNOVIAL PLICA
- ACHING ON SITTING DOWN ANTERIORLY, INTENSE THE
FIRST WALKING STEPS IN THE MORNING
O/E: FELT BANDS, MEDIALLY, MILD EFFUSION, PAIN ON
RESISTED KNEE EXTENSION MADE WORSE BY GLIDING
PATELLA MEDIALLY
- TREATMENT: REST, NSAIDS, CORTICOSTEROID INJECTION IF
MEDIAL PLICA PALPABLE. ARTHRO. EXCISION

69. 5. Infrapatellar fat pad5. Infrapatellar fat pad
syndromesyndrome
repetitive hyperextention injuries,repetitive hyperextention injuries,
surgical interventionsurgical intervention
pain on hyperextention over anteriorpain on hyperextention over anterior
knee regionknee region
part of patella baja: shorter patellarpart of patella baja: shorter patellar
tendon from fibrosis (? previoustendon from fibrosis (? previous
surgery) blocking knee flexionsurgery) blocking knee flexion

70. 5) INFRAPATELLAR FAT PAD SYNDROME
treatment:treatment:
rest from hyperextention (martial arts )rest from hyperextention (martial arts )
, NSAIDS, electrotherapy., NSAIDS, electrotherapy.
significant fibrosis: arthroscopicsignificant fibrosis: arthroscopic
excisionexcision

71. 6. Patellar tendonitis6. Patellar tendonitis
Also called “jumper’s knee”Also called “jumper’s knee”
Mxn:Mxn:
excessive running, jumping or kicking causing extremeexcessive running, jumping or kicking causing extreme
tension of the knee extensor muscle complextension of the knee extensor muscle complex
S/S:S/S:
Pain at the patellar tendonPain at the patellar tendon
POT over the distal pole of patellaPOT over the distal pole of patella
Pain increases with activityPain increases with activity
Thickening of tendonThickening of tendon
crepituscrepitus

72. TXTX::
RestRest
IceIce
HeatHeat
UltrasoundUltrasound
Cross-friction massageCross-friction massage
NSAIDSNSAIDS
Patellar tendon strap/tapingPatellar tendon strap/taping
Modify activityModify activity

73. 7. Bursitis7. Bursitis
Can be acute, chronic, orCan be acute, chronic, or
recurrentrecurrent
Numerous bursae involved butNumerous bursae involved but
most commonly injured are themost commonly injured are the
prepatellar or the deepprepatellar or the deep
infrapatellarinfrapatellar

74. Bursitis
Mxn:Mxn:
falling directly on kneefalling directly on knee
Continuous kneelingContinuous kneeling
Overuse of patellar tendonOveruse of patellar tendon

75. Bursitis
S/S:S/S:
Localized swelling that is similarLocalized swelling that is similar
to a water balloon and is outsideto a water balloon and is outside
the knee jointthe knee joint
Pain especially with pressurePain especially with pressure

76. Bursitis

77. Bursitis

78. Bursitis
Tx:Tx:
RestRest
IceIce
CompressionCompression
NSAIDSNSAIDS
Padding for protection when returning toPadding for protection when returning to
activityactivity

79. Vascular InjuryVascular Injury
~20% (5-30%) of all~20% (5-30%) of all
dislocationsdislocations
EMERGENCY if NO distalEMERGENCY if NO distal
perfusionperfusion
Patterns of Vascular injuryPatterns of Vascular injury
• rupturerupture
• incomplete tearincomplete tear
• intimal injury (may causeintimal injury (may cause
thrombosis)thrombosis)

80. Neurologic InjuryNeurologic Injury
CommonCommon peroneal nerveperoneal nerve
palsypalsy
Incidence ~20% (10-40%)Incidence ~20% (10-40%)
Most Common with varusMost Common with varus
injuryinjury
PROGNOSIS is POORPROGNOSIS is POOR
Complete recovery ~ 20%Complete recovery ~ 20%