|
Medical Definition of Spina iliaca posterior superior
1. The posterior extremity of the iliac crest, the uppermost point of attachment of the sacrotuberous and posterior sacroiliac ligaments; a readily apparent dimple occurs in the skin overlying the posterior superior iliac spine which is clinically useful as an indication of the level of the S-2 vertebra, the level of the inferior limit of the subarachnoid space. Synonym: spina iliaca posterior superior. (05 Mar 2000)