During hip internal rotation MMT with anti-gravity testing, where is stabilization performed?

During hip internal rotation MMT with anti-gravity testing, where is stabilization performed?

• A. Stabilization at the pelvis.
• B. Stabilization at the ankle.
• C. Stabilization at the distal thigh on the medial side of the knee.
• D. Stabilization at the proximal thigh.

Answer: (C)

The key idea is to fix the moving segment so the rotation you’re testing really comes from the hip joint, not from other joints or the pelvis. For hip internal rotation against gravity, stabilizing the distal thigh on the medial side of the knee accomplishes that. Gripping the distal thigh there locks the femur in place at the knee, preventing the knee or lower leg from contributing to the motion and keeping the pelvis from tilting or rotating as a substitute. This lets the patient recruit the hip internal rotators (like the gluteus minimus/medius and related muscles) to drive the inward turn of the thigh. Stabilizing higher up at the pelvis could allow pelvic movement to assist the motion and contaminate the result. Stabilizing at the ankle wouldn’t control the thigh’s rotation enough and could involve the ankle or tibial segments. Stabilizing the proximal thigh alone may still permit compensations through the knee or hip, reducing isolation of the hip joint. Hence, stabilizing the distal thigh on the medial side of the knee provides the most reliable isolation for hip internal rotation during anti-gravity testing.

The key idea is to fix the moving segment so the rotation you’re testing really comes from the hip joint, not from other joints or the pelvis. For hip internal rotation against gravity, stabilizing the distal thigh on the medial side of the knee accomplishes that. Gripping the distal thigh there locks the femur in place at the knee, preventing the knee or lower leg from contributing to the motion and keeping the pelvis from tilting or rotating as a substitute. This lets the patient recruit the hip internal rotators (like the gluteus minimus/medius and related muscles) to drive the inward turn of the thigh.

Stabilizing higher up at the pelvis could allow pelvic movement to assist the motion and contaminate the result. Stabilizing at the ankle wouldn’t control the thigh’s rotation enough and could involve the ankle or tibial segments. Stabilizing the proximal thigh alone may still permit compensations through the knee or hip, reducing isolation of the hip joint. Hence, stabilizing the distal thigh on the medial side of the knee provides the most reliable isolation for hip internal rotation during anti-gravity testing.