Knee Capsule — Medial (Midportion)

capsula articularis medialis genus (portio media)

The mid-third medial capsular ligament runs between the superficial MCL and the coronary ligament layers, tethering the medial meniscal body to the tibial and femoral surfaces at the mid-joint line. Its disruption produces the mid-body meniscal tear pattern and medial capsular sprain. Combined MCL-medial capsular tears produce the valgus instability of Grade III MCL injuries.

Region: Knee

Anatomical Data

Origin, Insertion & Supply

Origin	Medial femoral condyle mid-portion
Insertion	Medial tibial condyle and medial meniscal body periphery

Biomechanics

Function & Actions

Actions	Mid-third medial knee stability; tethers the medial meniscal body to the tibia and femur

Clinical Relevance

Clinical Notes

Mid-third medial capsular ligament injuries present as medial joint line tenderness at the level of the meniscal body (as opposed to the coronary ligament at the tibia or the superficial MCL at the femur). MRI demonstrates the capsular disruption as soft tissue oedema medially at the joint line level. Isolated medial capsular injuries heal with conservative management.

Pathology

Common Injuries & Conditions

Medial Capsular Ligament Sprain

Mid-third medial knee capsular tear producing medial joint line pain managed conservatively with functional bracing.