The pelvic teardrop, also known as U-figure or Köhler's teardrop, is a radiographic feature seen on pelvic x-rays and results from the end-on projection of a bony ridge running along the floor of the acetabular fossa.
This was shown to be the case by demonstrating that sawing away this bony plate made the feature disappear. It has also been confirmed by Vare in 1952 by applying a thin "strip of lead foil applied to the acetabular fossa and curving round the inferior margin of this, up over the inner wall of the lesser pelvis as far as the ilio-pectineal eminence."
- 1. Sharp, Ian K. "Acetabular dysplasia: The Acetabular Angle" J Bone Joint Surg Br 1961 43-B: 268-272
- 2. Buttler P. Applied radiological anatomy. Cambridge University Press. (1999) ISBN:0521481104. Read it at Google Books - Find it at Amazon
- 3. Kölbel R, Golzo H. [Köhler's "tear drop". Relationship between the radiologic picture and anatomic substrate]. (1977) RoFo : Fortschritte auf dem Gebiete der Rontgenstrahlen und der Nuklearmedizin. 127 (4): 326-33. doi:10.1055/s-0029-1230710 - Pubmed