Kalmia Latifolia

A slight ridge is sometimes seen commencing about the middle of the intertrochanteric crest, and reaching vertically downward for about 5 cm. along the back part of the body: it is called the linea quadrata (or quadrate line), and gives attachment to the Quadratus femoris and a few fibers of the Adductor magnus.

References

This article incorporates text in the public domain from page 246 of the 20th edition of Gray's Anatomy (1918)