[Music] the knee joint the knee joint is a complex joint that includes a hinge type of sinovial joint between the femur and tibia as well as a plain gliding joint between the patella and the femur the following bones take part in the formation of the joint Condes of the female both bult backwards and are separated by an interc condill Notch anterior surfaces articulate with the patella rest of the surfaces articulate with the tibial Condes and minisi conds of the tibia both are concave and are situated on the upper end of the tibia the concavity is deepened by the minisi in interc cond area of the tibia it intervenes between the articular surfaces of the condil it is wide in front and behind with a central constriction anterior part gives attachment to the anterior Horn of the medial miniscus anterior cruciate ligament anterior Horn of the lateral miniscus the posterior part gives attachment to the posterior horn the lateral miniscus the posterior horn of the medial miniscus and the posterior cruciate ligament articular surface of the patella the patella is a large seso bone held completely within the patella ligament and quadriceps femoris tendon the posterior surface of the patella is mostly articular except a small area close to the Apex where the ligamentum patella is attached ligaments capsular ligament a fibrous capsule surrounds the knee joint to add to its stability medially the capsule is attached to the medial meniscus and is strengthened by the tibial collateral ligament however laterly the capsule does not attach to the lateral meniscus posteriorly it is strengthened by the oblique poal ligament anteriorly it blends with the ligamentum patella it is deficient above the patella where it is pierced by the super patellar Bersa and behind the lateral condal of the tibia where it is pierced by the tendon of the popus anterior cruciate ligament it is an intracapsular ligament it is attached to the medial aspect of the superior surface of the tibia and the lateral aspect of the inferior surface of the femur it is tightest when the knee is extended and limits hyperextension of the knee it prevents forward displacement of the tibial condil it is weaker than the posterior cruciate ligament and is more frequently damaged injury to the ligament is often associated with damage to the tibial collateral ligament and the medial meniscus posterior cruciate ligament it is also an intracapsular ligament but it's stronger than the anterior cruciate Li it is attached to the lateral aspect of the superior surface of the tibia and the medial aspect of the inferior surface of the femur it is tightest to when the knee is flexed and therefore limits flexion it also prevents backward displacement of the tibial Condes medial collateral ligament or tibial collateral ligament morphologically it is the detached ishkal part of the adductor Magnus it is attached above the medial epicondilite divides into superficial and deep Parts The Superficial part is attached below to the medial cile and the shaft of the tibia the Deep part is attached to the medial tibial cond and medial meniscus and blends in with the capsule of the knee joint it resists excessive Abduction of the leg at the knee also known as valgus stress lateral collateral ligament or fibular collateral ligament this ligament is attached to the lateral cile of the femmer and lateral surface of the head of the fibula it supports the lateral aspect of the knee joint and is very strong and hence isn't commonly injured it resists excessive adduction of the leg at the knee also known as ver stress patellar ligament the patellar ligament is a continuation of the quadri femoris tendon inferior to the patella tension from the quadriceps femoris muscles is transferred to the tibia through the patella ligament to extend the leg at the knee a point to be noted the patellar tendon reflex or knee-jerk reflex is tested by tapping the patellar tendon or ligament with a reflex Hammer to elicit extension at the knee joint both afren and ephr limbs of the reflex arc are in the femoral nerve oblique poal ligament it is an expansion of the inserted fibers of the semimembranosus it extends Superior laterally and blends with the posterior part of the capsule arq ligament it is y-shaped the stem is attached to the styloid process of the fibula the anterior band is attached to the lateral cile of the femur the posterior band is attached to the medial cile of the tibia coronary ligaments these are parts of the fibers capsule which provide attachment to the minisi transverse ligaments these ligaments are present in 40% of individuals they extend from the Horn of the medial meniscus to the anterior margin of the lateral meniscus meniscal femoral ligaments it connects the posterior horn of the latal meniscus to the medial cile of the femur the anterior ligament is also called the ligament of Humphrey the posterior ligament is also called the ligament of risberg miniscus the minisi are fibrocartilagenous structures that provide padding to the articulating surfaces of the tibia and femur they increase the concavity of the tibial Condes they are malleable enough to accommodate the change in shape of the knee joint during flexion and extension they also act as shock absorbers due to the medial miniscus attachment to the fibers capsule of the knee and medial collateral ligament damage to either will often damage the medial miniscus as well the medial miniscus is shaped like the letter c it is firmly attached to the tibial collateral ligament and is more frequently damaged in the lateral miniscus the lateral miniscus is almost circular it is not fused to the lateral collateral ligament and floats more freely in the joint movements at the Joint extension range beyond the vertical axis is 5 to 10° flexion the range is 120° and 140° with a flexed hip medial rotation conjunct or adjunct lateral rotation conjunct or adjunct conjunct this takes place automatically during flexion or extension a a junct this takes place in a semiflex knee by active contraction bers at the Joint anterior bers prepatellar Bersa this lies between the skin and the anterior surface of the patella subcutaneous infra patellar Bersa this lies between the skin and the tubercle of the tibia deep infrapatellar Bersa this lies behind the patellar ligament super patellar Bersa this lies between the quadriceps femor tendon and the lower end of the femur lateral bers a Bersa between the fibular collateral ligament and tendon of the biceps femoris a BSA between the fibular collateral ligament and tendon of the popus and a Bersa between the tendon of the popus and latal femoral cile medial bers a Bersa which separates the tendons of the Sartorius gillus and semitendinosis from each other a Bersa between the tendon of the semimembranosus and medial collateral ligament and a Bersa between the tendon of the semimembranosus and medial tibial cile posterior B aersa between the lateral head of the gastrus and join capsule and a BSA between the medial head of the gastrus Ando capsule this is known as brois Bersa the following nerves inate the knee joint femoral nerve posterior division of the operator nerve sciatic nerve through the tibial and common peronal nerves the knee joint is supplied by the following arteries via the genicular an asmosis poal artery femoral artery and anterior tibular artery clinical correlation minuscal tear the medial meniscus is 20 times more prone to injury than the lateral meniscus it is firmly adherent to the Deep part of the tibial collateral ligament in forceful strains as an adduction and lateral rotation of the femur over the tibia with the foot firmly placed on the ground the medial meniscus gets torn this is because the medial collateral ligament does not allow the meniscus to move away from under the femoral cile it gets compressed and crushed between the femoral and tibial condal which are moving with great force part of the torn cartilage make get displaced this small piece floats in the D cavity and may get lodged between femoral and tibal condil causing locking of the knee joint in a flex position only the periphery of the miniscus has the potential to heal as it is vascular rupture of the cruciate ligaments rupture of the anterior cruciate ligament is more common than the posterior drawer sign is used to determine the Integrity of the ligaments anterior drawer sign this is the exessive forward movement of the tibia over the femur due to damage to the anterior cruciate ligament posterior draw sign this is the excessive backward movement of the tibia over the femur due to damage to the posterior cruciate ligament unhappy triad this is an injury to the knee joint which occurs when there's force from the lateral side of the knee with the foot firm on the ground it results in rupture of the tibial collateral ligament medial miniscus and the anterior cruciate ligament housemaid's knee this is prepatellar btis inflammation of the Bersa is often seen in housemates as they used to often kneel down for long periods of time clergyman's knee this is inflammation and swelling of the subcutaneous infrapatellar Bersa knee deformities these are common in young children and automatically get corrected as a child grows it is considered pathological when seen in teenagers or adults genu valgum or nocne here the tibia deviated laterally at the knee stretching the medial side of the joint and compressing the lateral side it predisposes to the latal dislocation of the patella genu varum or ble here the tibas deviated medially at the knee stretching the lateral side and compressing the medial side of the knee