MCL Sprain Flashcards
What, epidemiology, aetiology, pathophysiology, grades
What is a MCL Sprain?
A tear to the Medial collateral ligament.
Epidemiology of MCL injury
Male higher
Sporting injury
Aetiology of MCL Injury
Lateral force to the knee while the foot is fixed
Places an increased valgus or abduction and rotational stress in the knee resulting in overstretching.
Repeated stress to the knee, causes ligament to loose elasticity
Clinical features of MCL injury
- Severe pain
- Excessive swelling
- Difficulty moving
- Difficulty weight baring
- Stiffness
What are the grade of tears?
Grades 1, 2 and 3
What is grade 1?
Mild strain Tenderness over medial tibial/femoral condyle No swelling Pain No laxity
What is grade 2?
Moderate Marked tenderness Maybe swelling Some laxity- distinct end point Stable in full extension
What is grade 3?
Severe Compete tear Feeling of instability Pain is variable Gross laxity- no distinct end point Instability in extension
What is the pathophysiology of a MCL sprain?
A disruption of the connection between the medial femur and medial tibia -> valgus instability.
What is the healing process?
Hemostatsis- bleeding. Platelets in contact eith collagen results in activation. Prothrombin is converted to thrombin and fibrrinogen is converted to fibrin. Form fibrin cross-linking to strengthen the platelet clumps into a stable clot coagulation. 4-6hrs.
Inflammation- focuses on destroying bacteria/removing debris. White blood cells (neutrophils) enter the wound and destroy bacteria. An inflammatory response releases inflammatory cytokines e.g serotonin , bradykinin, histamine. Onve neutophils leaves macrophages enter clear debris. Secrete growth factors/proteins to facilitate repair. 5 cardinal signs of inflammation.
Proliferation- distinct stages with stage.
1. Filling wound - shiny, deel, red granulation tissue fills the wound bed with connective tissueand new blood vessels are formed
2. Contraction of wound margins- wound margins pull towards the centre if wound.
3. Covering the wound (epithelialisation)-> epithelial cells arise from the wound bed it margins and migrate across the wound until completely covered
4 - 24 days
Remodeling- new tissue slowly gains strength/flexibility. Collagen fibres reorganise the tissue remodels/matures. Increase in tensile strength (max strength limited to 80% of preinjured strength) 21 days - 2 years
What is the MCL?
Band of tissues on the inside of the knee.
Connective tissue from the medial epicondyle of the femur to the medial condyle of the tibia.
What does the MCL do?
Provides valgus stability to knee
Most common ligament injury
