Trendelenburg's sign

This observation is referred to clinically as a positive Trendelenburg's sign.

In a positive Trendelenburg's sign the pelvis sags toward the normal unsupported side (the swing leg).

Dysfunction of the gluteus medius or the superior gluteal nerve can potentially be indicated by a positive Trendelenburg's sign.

Trendelenburg's sign is found in people with weak or paralyzed abductor muscles of the hip, namely gluteus medius and minimus.

His paternal grandfather, Friedrich Trendelenburg (1844 to 1924) was the surgeon after whom Trendelenburg's sign for hip abductor weakness and the Trendelenburg test for varicose veins are named, whereas his father, Paul Trendelenburg (1884 to 1931), also was a pharmacologist.