Hip and Knee Joint

Question 1

Describe the symptoms of piriformis syndrome and discuss the view that a common variant of piriformis / sciatic nerve anatomy might contribute to this condition.

Answer 1

• numbness and tingling in the buttocks that may extend down the back of the leg.
• tenderness of the muscles in the buttocks.
• difficulty sitting comfortably.
• pain while sitting that gets worse the longer you sit.
• pain in the buttocks and legs that worsens with activity.

Question 2

What is the Trendelenburg sign and what does it signify?

Answer 2

• The Trendelenburg sign is a quick physical examination that can assist the therapist to assess for any hip dysfunction

Question 3

Mild weakness of the hip abductors may contribute to an increased risk of lumbar spine injury in bowlers in cricket. Describe the link.

Answer 3

• The hip abductor muscles help to raise your leg to the side, away from your body. They also help support your pelvis when you’re standing on one leg. When these muscles are weak, it can affect your balance and mobility. It can also cause low back pain due to instability.

Question 4

What is the role of the knee’s menisci?

Answer 4

• The menisci of the knee joint are crescent-shaped wedges of fibrocartilage that provide increased stability to the femorotibial articulation, distribute axial load, absorb shock, and provide lubrication to the knee joint.

Question 5

Describe the screw-home rotation of the knee, explain its functional benefits and name the muscle that acts as the ‘key’ to the locked knee.

Answer 5

• The “screw-home” mechanism, considered to be a key element to knee stability, is the rotation between the tibia and femur
• External rotation occurs during the terminal degrees of knee extension and results in tightening of both cruciate ligaments, which locks the knee.
• Popliteus

Question 6

7. Why might a tight iliotibial band lead to incorrect tracking of the patella?

Answer 6

• Tight lateral structures have been implicated in subjects presenting with patellofemoral pain syndrome (PFPS). It has been proposed that a tight iliotibial band (ITB) through its attachment of the lateral retinaculum into the patella could cause lateral patella tracking, patella tilt and compression

Question 7

Describe Lombard’s paradox and explain the recent evidence that suggests no real paradox exists during the squat

Answer 7

• Lombard’s paradox describes a paradoxical muscular contraction in humans. When rising to stand from a sitting or squatting position, both the hamstrings and quadriceps contract at the same time, despite them being antagonists to each other

Question 8

11. Coactivation of knee extensors and flexors does occur during certain movements. What are the proposed benefits of coactivation in these cases?

Answer 8

• Muscle coactivation or cocontraction is the simultaneous activation of agonist and antagonist muscles. It is believed to be an important motor control strategy to improve joint stability1–3 and movement accuracy.