Ligaments of knee joint

Middle genicular artery

-Middle genicular artery is a branch of popliteal artery and supplies the cruciate ligaments & the synovial

membrane of knee joint.

-lt reaches the interior of knee by piercing the oblique popliteal ligament of the knee.

-Fibular head artery (A) is the circumflex fibular branch given by the posterior tibial artery, which contributes towards the anastomosis around the knee joint.

-Descending genicular artery (B) is a branch of femoral artery and also contributes to the knee joint anastomosis.

-Superior genicular artery (C) is a branch of popliteal artery and is an important branch in the anastomosis around the knee joint.

Cruciate ligaments are found in the knee and not ankle. Cruciate ligaments are pairs of ligaments arranged like a letter X. They are the anterior cruciate ligament (ACL) and the posterior cruciate ligament (PCL). They maintain anteroposterior stability of the knee joint.

Posterior cruciate ligament is stronger than the ACL and attaches to the posterior intercondylar area of the tibia. The posterior cruciate ligament ascends in an anteromedial direction to attach on the lateral surface of the medial femoral condyle.The posterior cruciate ligament resists posterior translation of the tibia on the femur or anterior translation of the femur on the tibia.

Functions of posterior cruciate ligament:

• Stabilises knee
• Prevents posterior dislocation of the tibia on femur
• Limits hyper extension of knee only if the anterior cruciate is ruptured

A i.e. Anterior dislocation of tibia

A i.e. Posterior cruicate ligament

 Middle genicular

• Oblique popliteal ligament is an expansion from the tendon of semimembranosus attachment to intercondylar line of femur.
• It is closely related to popliteal artery and is pierced by middle genicular vessels and nerve and the terminal part of the posterior division of the obturator nerve.

Ans. is ‘b’ i.e., Posterior cruciate ligament

Posterior cruciate ligament

• PCL begins from posterior part of intercondylar area of tibia and runs upwards, forwards and medially to attach the anterior part of the lateral surface of medial condyle of femur.
• PCL is extrasynovial but intracapsular, i.e., lies between synovium and capsule of the knee joint.
• It provides antero-posterior stability and prevents posterior gliding of tibia on femur.
• It is taut in flexion.
• Blood supply of cruciate (anterior & posterior) ligaments is from : –

1. Middle genicular artery (major supply)
2. Inferior genicular (medial & lateral) artery (less important).

• Nerve supply of cruciate ligaments (ACL & PCL) is from posterior articular branch of tibial nerve.

Posterior cruciate ligament (PCL)

• PC L begins from posterior part of intercondylar area of tibia and runs upwards, forwards and medially to attach the anterior part of the lateral surface of medial condyle of femur.
• PCL is extrasynovial but intracapsular, i.e. lies between synovium and capsule of the knee joint.
• It provides antero-posterior stability and prevents posterior gliding of tibia on femur.
• It is taut in flexion.
• Blood supply of cruciate (anterior & posterior) ligaments is from :-

1. Middle genicular artery (major supply).
2. Inferior genicular (medial & lateral) artery (less important).
3. Nerve supply of cruciate ligaments (ACL & PCL) is from posterior articular branch of tibial nerve.