approach to acute knee injuries include detail history, focused knee exam and imaging/invasive procedure,Diagnosis is made at history most of the times.History should include mechanism of Injury,location of pain, mechanical symptoms like swelling/ effusion...

1. Approach To Acute Knee Injuries
Insp Dr Mahadev Deuja
NPH
Wednesday, April 11, 2018

2. Case
29/M basic technical police trainee
 History
Rt knee injury during shuttle race (frequent change in
direction)
Rt knee pain, swelling, difficultly weight bearing and unable
to extend Rt knee completely
P/H/O recurrent b/l knee joint instablity

3. Examination of Rt knee
 Look
Gait- antalgic, minimal joint effusion
 Feel
Mid-line joint tenderness
 Move
Extension lag and restricted ROM

4.  DNVS-intact
 Special test
Valgus stress test- positive
Lachman test and anterior drawer- doubtful

5. MRI
 Complete ACL tear +
bucket handle MM tear +
MCL sprain Grade-2 of Rt
knee
 Unhappy triad

6. Management
 Arthoscopic ACL reconstruction + MM repair
 Physiotherapy

7. After 9 weeks
Same patient came to opd in wheel chair
 History
Following twisting injury of the next (left) knee
while steeping down from stairs

8. Examination of left knee
 Look
Gait- antalgic, minimal joint effusion
 Feel
Mid - line joint tenderness
 Move
Extension lag and restricted ROM

9.  DNVS-intact
 Special test
Valgus stress test- positive
Lachman test and anterior drawer- doubtful

10. MRI
Complete ACL tear +
bucket handle MM tear-
left knee

11. Management
 Arthoscopic Acl reconstruction + MM repair
 Physiotherapy

12. Knee injuries
 Common injury
Unstable design
Exposure to external environment
Functional demand
 Being major weight bearing joint knee injuries have significant
disability
 Annually >1 million ER visits and 1.9 million OPD visits are of
acute knee injuries.(US)

13. Patients presenting with an acute effusion/hemarthrosis
Diagnosis ?

14. In order to have an acute hemarthrosis IN the
knee, something INSIDE the knee must be
injured
D.D’s
1. Intra-articular Fracture
2. ACL / PCL Tear
3. Patellar Dislocation/ Subluxation
4. Meniscus Tear

15. Remember that MCL and LCL are
EXTRAarticular structures and isolated
collateral ligament injuries donot cause an
acute hemarthrosis

16. Approach to knee injuries
History
Focused knee
exam
Imaging/invasive
procedure
May be difficult in acute setting,
reevaluation can be done once
swelling and pain subsides

17. History
 Diagnosis is made at history most of the times
Mechanism of Injury
Location of Pain
Mechanical Symptoms
Swelling/ Effusion
Past history
Available at: http://www.orthobullets.com/knee-and-sports/3003/history-and-physical-exam-of-the-knee. Accessed February 11,
2018.

18. Mechanism of injury
 Helps predict injured structure
 Contact
 Non contact

19. contusion, fracture
PCL/joint capsule sprain
ACL/joint capsule sprain

20. MCL/ meniscus LCL/ meniscus ACL/ meniscus

21. Location of pain
 Anterior, medial, lateral, posterior
 Over joint line, bone and soft tissue structure

22. Mechanical symptoms
 H/o locking episodes suggests a meniscal tear.
 A sensation of popping at the time of injury suggests
ligamentous injury
 Episodes of giving way are consistent with some degree of
knee instability and may indicate patellar subluxation or
ligamentous rupture.

23. Effusion / swelling
 Rapid onset of a large, tense effusion suggests ACL rupture
or tibial plateau fracture
 Slower onset mild to moderate effusion is consistent with
meniscal injury or ligamentous sprain.
 Recurrent knee effusion after activity is consistent with
meniscal injury

24. Past History
 Knee instability, knee surgery and use of medication for knee
pain

25. Knee examination
 Always compare with normal knee
 Look
abrasions, ecchymosis and localized swelling
provide clues to the magnitude of force and the MOI
 Feel
patella and its supporting structures
Joint lines and collateral ligaments ,bones for tenderness,
crepitus and localized swelling

26.  Move
Assess active and passive ROM
Locking or extension lag may suggest meniscal injury, intra
articular loose bodies
 Assess DNVS

27. Special test
Anterior Drawer Test.
Lachman's Test.
Posterior Drawer Test.
McMurray's Test.
Apley's Test.
Collateral Ligament Stress Test.
Patallo femoral assessment.

28. Anterior Drawer
Test
Supine and knee
flexed to 90
Sit on the
patient's foot and grasp
around the calf
Anterior force
Tibial glide > 5mm –
ACL laxity
•Least reilable-
influenced by hamstring
spasm

29. Lachman test Flex knee 20-30
Stabilize thigh
Tibia is pulled
forward
>3mm displacement
& soft end point- +ve
lachman
•Most sensitive test

30. Posterior drawer test
Supine and knee
flexed to 90
Sit on the
patient's foot and grasp
around the calf
Posterior force
Tibial glide is compared

31. McMurray’s test
Knee joint –completely
flexed
Foot is rotated externally
and leg abducted
Knee is slowly extended
keeping leg externally
rotated and abducted
Patient may experience
pain or a click may be
heard- MM tear
Posterior tear – pain at more
flexed position
Similar test with foot internally
rotated and leg adducted is
carried out – LM tear

32. Collateral Ligament
Stress Test
Pain at ligament – partial tear
Minimal pain at ligament with
wide joint opening- complete
tear
Knee is flexed to
20-30·
Gently
abducted(test MCL)
and adducted (test
LCL)
Look for pain and
use finger at joint
line for joint
opening

33. Clinical evaluation clues to ACL injury
History
• Non-contact
injury
• Landed awkwardly
• Felt "pop”
• Immediate
swelling
PE
• Large
hemarthrosis
• Lachman
• Anterior drawer
positive

34. Clues to PCL injury
History
• Struck
dashboard
• Fall with PF
foot
• Posterior knee
pain
PE
• Posterior sag
sign
• Posterior
drawer

35. Clues to meniscal injury
History
• Mechanical
symptoms
(catching,
locking),
• Pain at joint line
• Delayed swelling
PE
• Joint line
tenderness
• McMurray
positive

36. Clues to patellar injury
History
• Fall with DF foot
• May feel 2 "pops“
• Swelling
• Anterior pain, Pain
with stairs
PE
• Patellar
apprehension
• Tender over MPFL
• Effusion, Patellar
crepitus
• Pain with active
compression

37. Clues to fracture
History
• High velocity
injury
• Inability to
bear weight
immediately
PE
• Abrasion
• Ecchymosis
• Deformity
• Crepitus

38. Imaging
 Plain radiograph
 MRI
 CT scan
 USG

39. Plain radiography
 Initial imaging modality of choice
 Baseline views are anteroposterior (AP) and lateral
 If the lateral view is normal in the setting of acute trauma a
fracture is unlikely

40. MRI
 If examination and initial imaging studies are inconclusive or
intra-articular and ligamentous injuries are suspected
 Significantly affects the clinical decision-making process
 Often prevent unnecessary knee arthroscopy

41. CT-scan
Useful in
Complex knee injuries to reveal fracture anatomy
Cases where fracture is suspected but radiographs are
negative
Assessment of tibial plateau fractures (comparable
accuracy to MRI)
Along with MRI can improve surgical planning

42. USG
 Quick and inexpensive
 Useful in dynamic evaluation of superficial soft tissue
structures
tendon lesions, joint effusions, bursitis, and cysts

43. ACL injury
 US statics
 200,000 ACL-related injuries
100,000 ACL reconstructions each year.
 Incidence is higher among basketball, football, skiing, and
soccer player.
 Females >> males
1.6-fold greater rate of ACL tears per athletic exposure in
high school female athletes than males.
 A study by Gornitzky

44.  Associated with meniscal tears in up to 50% of patients
Acute >> Lateral
Chronic >> Medial
 Risk of reinjury is 15 times higher than general population
 Don’t miss the diagnosis - consequences can be devastating
Medial meniscus injury (Bucket Handle Tear)
Articular cartilage injury

45. Anatomy
 Fibrous collagenous connective
tissue that attaches the femur to
the tibia.
 Primary (85%) restraint to anterior
translation of the tibia.
 Secondary restraint to tibial rotation
and varus/valgus angulation at full
extension.

46. Mechanism of injury
 Noncontact injury (80%)
Deceleration, changing
direction, cutting injuries, or
landing from a jump
 Contact and high-energy
traumatic injuries (20%)
With other ligamentous and
meniscal injuries.

47. Hx:
 Hearing or feeling a “pop” & knee gives way
 Significant swelling quickly (< 1 hour)
 Unable to continue play or activities due to pain, swelling and
instability or giving away
 ↓ range of motion (ROM)
 Achy, sharp pain with movement

48. Physical examination
 Look
Immediate effusion = significant intra-articular trauma.
 Feel
Joint line and bony tenderness- associated injury
 Assess ROM:
Lack of complete extension- bucket handle MM tear/
associated loose fragments
 Special tests- lachman and anterior drawer test positive

49. Xray
Segond Fracture
- Rarely seen
- Pathognomonic
for ACL tear
- Avulsion #
Most x-rays
will be NORMAL

50. Mri
 Gold standard
 Sensitivity -90 to 98%.
 Fiber discontinuity, altered
course, abnormal signal of
ligament- acl tear
 Bone bruising- 90%
 Also helps to identifying
associated ligament,
meniscal, or articular cartilage
injury
Normal ACL Torn ACL
Bone bruising

51. Treatment
Surgical/conservative?
Physiotherapy

52. Surgical
 Replacing torn ACL with a tendon graft
 2 most common grafts are
Patellar tendon graft
Hamstring graft
 Goal
Prevent further damage to meniscus &cartilage and osteoarthritis.

53. The ACL reconstruction with a bone-
patellar-tendon-bone auto graft
Passed drill
Section of patella and
tendon removed
Patella tendon inserted

54. ACL reconstruction with a semitendinosis and/or
gracilis- tendon auto graft
Passage drilledHamstring graft prepared
Hamstring graft
inserted

55.  the expected long-term success rate of ACL reconstruction is
between 75-95%.
 Upto 80% of people return to pre injury state
 Failure is mainly due to: recurrent instability, graft failure, or
arthrofibrosis.
 Return to all sports activity may take 6-9 months

56. Meniscus injury
 most common indication for knee surgery
 higher risk in ACL deficient knees

57.  Medial tears
more common - less
mobile
 Lateral tears
more common in acute
ACL tears

58. Causes:
 Sudden twisting
 Young athletes
 Simple movements
 Older knee

59. Hx:
 Clicking, catching or locking
 Worse with activity
 Tends to be sharp pain at joint line
 Effusion

60. PE:
 mild-moderate effusion
 pain with full flexion
 tender at joint line
 + McMurray’s

61. Mri
 Low-signal intensity
black triangle =normal
White interruption =lesion

62. Take home message
 Think of 4 things when faced with a traumatic large acute hemarthrosis:
1. Fracture 2. ACL /PCL Tear
3. Patellar Dislocation 4.Quadriceps/Patellar Tendon rupture
 Clinical evaluation gives diagnosis most of the times
 MRI are helpful in diagnosing doubtful cases of ligament and meniscal
injuries
 Fractures can be easily diagnosed on X-ray
 Ct scan is helpful for suspected cases of intra articular fractures
 ACL Tears and meniscal injuries are very common

63. Mcq
 Most sensitive test to diagnose ACL tear is
1. Anterior drawer test
2. Lachman test
3. Posterior drawer test
4. McMurray test

64.  Unhappy triad in knee injury is combination of
1. ACL + MCL+ LM injury
2. ACL + MCL + MM injury
3. ACL + LCL + LM injury
4. ACL + PCL + MM injury

65.  Medial meniscus tear is more common than lateral because it
is
1. Larger in size
2. Less mobile
3. Medial rotation is more than lateral rotation
4. Fibroelastic

66. Refrences
 Available at: http://bestpractice.bmj.com/topics/en-gb/575. Accessed
February 11, 2018.
 Available at:
http://caep.ca/sites/caep.ca/files/caep/CAEP2015/Presentations/hui_caep
_2015. Accessed February 16, 2018.
 Campbell's Operative Orthopaedics International Edition. 2016.
 http://www.imagingpathways.health.wa.gov/index.php/imaging-
pathways/musculoskeletal-trauma/bone-and-joint-trauma/post-traumatic-
knee-pain. Accessed February 11, 2018.
 http://www.orthobullets.com/knee-and-sports/3003/history-and-physical-
exam-of-the-knee. Accessed February 11, 2018.

67. Thank you