- Trendelenburg test: clinical test of the hip abductor mechanism (gluteus medius and minimus), performed by observing the pelvis while the patient stands on one leg.
- A positive test (Trendelenburg's sign) is sagging of the pelvis on the unsupported side.
Abductor Mechanism of the Hip Joint
Abductor mechanism of the hip joint
Component
Power (P)
- Provided by
- Gluteus medius and minimus, acting as abductors of the hip joint
Fulcrum (F)
- Provided by
- Hip joint
Weight (W)
- Provided by
- Head and neck of femur
Normal versus Positive Test
- Normal: acting from below, gluteus medius and minimus of the stance side hold the pelvis level on the unsupported side during walking, provided the hip joint and neck-shaft angle of the femur are normal.
- Positive test: when gluteus medius and minimus of the stance side are paralysed, usually from superior gluteal nerve injury, the pelvis sags on the unsupported (normal) side instead.
- The superior gluteal nerve also supplies tensor fasciae latae, paralysed alongside gluteus medius and minimus in nerve injury.