2. Knee
Related anatomy
Superficial, Uni-axial, load bearing joint
Structures stabilizing the knee
Bone
Soft tissue
Synovium & capsule
Ligaments: Collateral,
ACL and PCL
Menisci : Medial & Lateral
Muscles and tendons
3. Knee
Related anatomy
Structures stabilizing knee
Muscles and tendons
Quadriceps
Gastronemius
Hamstrings
Popliteus
Iliotibial band
Pes anserinus :
Sartorius, Gracilis & Semitendinoses
4. Collateral ligaments
Related Anatomy
Located at the inner and outer side of knee
Connects femur to tibia (MCL) & fibula (LCL)
Injuries by varus /valgus forces on knee
The LCL is rarely injured
6. Collateral ligaments
Clinical features
Pain, swelling over medial / lateral aspect
Inability to walk due to pain : instability: 0
tear
Instability : giving way of the joint
Depending on degree of tear (0 tear):
Effusion : first degree tear
Haemarthrosis : 2nd and 3rd degree tears
Patella tap positive
Varus / valgus stress test positive
Apley’s distraction test
9. Management
Investigations
• Ligament injuries are not visualised on X-rays
• Often associated with Meniscal and ACL tears
• MRI useful to confirm diagnosis
Collateral ligaments
Grade 1 Grade 2 Grade 3
10. Management : Investigations
• Ligament injuries are not visualised on X-rays
• MRI useful to confirm diagnosis
Partial tear
Conservative treatment suffice
RICE : Rest, Ice, Compression, Elevation
Rest the knee to give the ligament time to heal
Ice : 2-3 / days :15 to 20 minutes each
Compress the site to limit swelling
bandage or brace for a while
Elevate the knee whenever possible
Rehabilitation exercises for good healing
Collateral ligaments
11. Management
Complete tear
May need surgery : repair returns stability
Rehabilitation plan necessary
After satisfactory rehabilitation, previous levels
of activity usually regained
Rehabilitation
Passive ROM exercises to restore flexibility
Braces to control joint movement
Exercises : strengthen quadriceps
Collateral ligaments
12. Cruciate ligaments
Derived from “crux”: meaning cross / “crucial”
Criss-cross each other to form an “X"
Intra-articular & connects femur to tibia
Made of many strands & functions like short
ropes holding the knee joint tightly in place
when the leg is bent or straightened
2 cruciates
anterior cruciate ligament (ACL)
posterior cruciate ligament (PCL)
13.
14.
15. ACL function
Prevents tibia from
sliding forwards
beneath the femur
ACL injuries
Injured in several ways :
Changing direction rapidly
Landing: following a jump
(skiing, gymnastics)
Direct contact: football tackle
Anterior cruciate ligaments
16. May be isolated injury-usually combines with
mesiscus & collateral tears
No pain immediately
Knee gives way during
fall - popping sensation
- feel of structure tear
within knee-numbness
Haemarthosis - pain
Anterior cruciate ligaments
Walking or running on an injured ACL, can further
damage the articular cartilage in the knee
17. Haemarthrosis and Effusion
Haemarthrosis Effusion
Swelling seen
immediately after the
injury : 15-20 minutes or
sooner
Swelling comes after >6-
12 hours of injury
Indicates cruciate or
peripheral meniscal lesion
in the absence of a
fracture
Indicates a tear of the
meniscal body or synovial
injury / irritation
Patella tap positive Patella tap positive
18. Diagnosis : Based on
Thorough physical examination of knee
Anterior drawer test
Lachman test
Pivot shift test
Anterior cruciate ligaments
O’Donoghue’s
“unhappy” /
“terrible” triad
21. Pivot shift test
Pivot-shift test
Knee held in extension
Leg internally rotated
Valgus force at knee
Knee slowly flexed
Anteriorly subluxated tibia reduces on flexion
24. Management
Partial tear may or may not require surgery
Complete tears, especially in younger
athletes - may require reconstruction
Conservative
Used in overall low activity level patients
If the overall stability of the knee is good
Involves treatment program
muscle strengthening
use of a brace to provide stability
Anterior cruciate ligaments
25. Management
Operative treatment
Arthroscopic
Open surgery
Combination
Procedure
Strip of tendon, taken from the patient’s knee
patellar tendon
hamstring tendon (semitendinosus)
passed through joint and secured to femur & tibia
Anterior cruciate ligaments
28. Strong ligament
Not frequent as ACL tear
Mechanism of injury
A blow to front of knee
Fall on a bent knee
Dashboard injury
Hyperextension : dislocated knee
PCL injuries disrupt knee joint stability
because the tibia can sag backwards
PCL injuries may be isolated or combined
Posterior cruciate ligament
29. Symptoms
Immediate swelling - haemarthrosis, pain +
Inability to walk : pain, instability
Instability : knee “giving way”
Posterior cruciate ligament
Mechanism of injury : PCL
30. Clinical
Sag test
Posterior drawer test
Quadriceps active test
Reverse pivot shift test
PCL injuries
Sag Sign
33. Management
Isolated PCL injuries
May be either partial or complete tears
Can usually be treated conservatively
Combined PCL injuries
Injury to ligaments, bone, nerves/blood vessels
Usually require surgical repair
Posterior cruciate ligament
34. Structure Physical Test
ACL Anterior drawer, Lachman, Pivot-shift
PCL Posterior drawer, Posterior sag sign,
Quadriceps active test, Reverse pivot
shift test
Fib.col.lig Varus stress
Tib.col.lig Valgus stress
Patella Patellar apprehension for instability
Tests in the diagnosis injuries of ligaments