Other ligament injuries (MCL, LCL, PCL) Flashcards
Where does the PCL attach?
Postero-laterally on the tibial plateau to anterio-medially on the distal femur
What is the function of the collateral ligaments?
Resist valgus (MCL), varus (LCL) and external rotation forces of the tibia in relation to the femur
Why are adults more susceptible to MCL/LCL injuries?
Less elasticity with age
What is a common mechanism of MCL injury?
Blow to the lateral knee
Where does the MCL attach on the tibia in relation to the joint line?
4-5cm below the joint line
What test for the MCL is shown?
Valgus (abduction) stress test
How are MCL/LCL injuries diagnosed?
History and examination usually sufficient. If not:
- MRI
- XR - plain and stress
What are the clinical features of MCL injury?
- Medial knee pain
- Joint effusion usually not present as collateral ligaments are outside of the knee joint
- Tenderness
- Localised oedema
- Medial instability/laxity on valgus stress test- done at 30 degrees
- NB: positive valgus/abduction test in full extension is more indicative of PCL/ACL injury than MCL.
- Ecchymosis - 1-3 days after injury
What is the management of MCL/LCL injury?
RICE + physiotherapy - return to sports once pain free and 80-90% of strength regained
Protective ambulation - hinged knee brace for 4-6 weeks
NSAIDs
+/- MCL/LCL reconstruction repair - usually at 7-10days after injury
What are some complications of MCL injury?
Pellegrini-Stieda’s lesion - calcification adjacent to the adductor tubercle, due to non-healing collateral ligament injury, visible on AP
OA
Knee joint stiffness
Chronic MCL insufficiency
What is shown?
Pellegrini-Steida lesion
Are MCL or LCL injuries more common ?
MCL
When do PCL injuries usually occur?
Uncommon - occur in goalkeepers or dashboard injuries
Which autografts are used for cruciate ligament reconstruction?
Hanstring tendons and patella ligament
