Medial Meniscus vs Lateral Meniscus
Medial Meniscus vs Lateral Meniscus
The medial and lateral menisci are fibrocartilage structures that deepen the tibial plateaus and distribute load in the knee. Their different attachments and mobility explain why the medial meniscus is more commonly injured than the lateral meniscus.
Comparison Table
Key Differences
- →Medial meniscus is C-shaped and firmly attached to MCL; lateral is O-shaped and more mobile
- →Medial is more commonly injured due to reduced mobility and MCL attachment
- →Lateral meniscus has meniscofemoral ligaments; medial does not
- →Popliteus tendon separates lateral meniscus from LCL
Clinical Relevance
- •MCL injuries often involve medial meniscus (attached together)
- •Joint line tenderness suggests meniscal pathology (medial or lateral)
- •McMurray test: Positive with click/pain suggests meniscal tear
- •Peripheral tears can heal and should be repaired; central tears often require partial meniscectomy
Study Tips
- ✓Medial Meniscus = More injury, MCL attachment, less Mobile
- ✓Lateral meniscus = Ligaments (meniscofemoral), Loose attachment, Less injury
- ✓Remember the blood supply zones: peripheral (red) heals, central (white) doesn't
- ✓Popliteus tendon creates a "gap" that separates the lateral meniscus from the LCL
FAQs
Common questions about this comparison
The medial meniscus is firmly attached to the MCL and joint capsule, making it less mobile. During rotational stress or valgus force, the medial meniscus cannot move out of the way and gets trapped and torn between the femur and tibia. The lateral meniscus is more mobile and can move with the condyles.
Tear location is critical. Peripheral tears (red zone) have blood supply and can heal with repair. Central tears (white zone) are avascular and won't heal, so they are treated with partial meniscectomy. Tear pattern, patient age, and associated injuries also influence the decision.