Thigh and Knee Joint

Question 1

Midshaft femoral fracture

Answer 1

Called a spiral fracture. Not as common as femoral head fractures since the femoral shaft is large and strong. However, these fractures can occur following a car accident, when the blow to the bone is substantial.

Question 2

Genu Varum

Answer 2

A varus deformity of the knee joint; the femur is abnormally vertical and the resulting Q angle is small. In these situations, unequal, medially directed weight-bearing results in damage to the menisci and joint cartilage, often leading to osteoarthritis (arthrosis). In addition, there is an excessive amount of stress placed on the lateral (fibular) collateral ligament. The individual is said to have a “bow leg”.

Question 3

Genu valgum

Answer 3

A valgus deformity of the knee joint; the femur is abnormally oblique and the resulting Q angle is greater than normal. In these situations, unequal, laterally directed weight distribution produces undue stress on the medial (tibial) collateral ligament and the lateral meniscus, as well as the articular surfaces of the lateral femoral and tibial condyles. The individual is said to have a “knock knee”

Question 4

Unhappy Triad

Answer 4

Three structures that are often injured simultaneously are the anterior cruciate ligament, the medial collateral ligament and the medial meniscus. Injury often results when a postero lateral force is applied to the knee, as occurs during a clip in football. A lateral/valgus force applied to the knee stresses the medial collateral ligament. If the force is to great, the ligament tears. Since the MCL and the medial meniscus are attached to each other, a medial meniscus tear ensues. The posterior component of the applied force drives the tibia forward on the femur, stressing the ACL. If the force is too great, the ACL also tears.

Question 5

Bursitis

Answer 5

commonly associated with inflammation of the numerous bursae associated with the patella. Bursae are closed fluid-filled sacs that act to reduce friction between gliding surfaces (e.g. between to bones, at a joint).

Question 6

Femoral n. damage (L2-L4) –

Answer 6

Damage to this nerve may result in wasting of the quadriceps femoris muscles. The individual has difficulty extending the knee; rising from a sitting position requires assistance; the patient has an abnormal gait characterized by planting the foot and flexing the trunk in order to maintain adequate balance.

Question 7

Sciatic n. lesion (“sciatica”) or radiculopathy of the L5 root –

Answer 7

may result in weakness of the hamstring muscles.

Question 8

Popliteal (Baker’s) Cyst

Answer 8

A synovial lined pouch within the popliteal fossa, formed by the accumulation of synovial fluid outside the knee joint capsule. While most resolve spontaneously, sometimes a cyst can be large enough to compromise blood flow in the popliteal vessels. The cyst can be palpated within the popliteal fossa. It often occurs as a result of injury or damage to the synovial membrane of the knee.