The calcar femorale. An anatomic, radiologic, and surgical correlative study.

In order to define the anatomy of the calcar femorale, a radiologic and surgical study was done on ten paired cadaver femurs. After radiography and computed tomographic (CT) scans, the specimens were subjected to medullary reaming by an experienced orthopedist, simulating total hip arthroplasty procedures. The imaging studies were repeated and compared with the prereaming studies. The calcar femorale was dissected from surrounding medullary bone, and sections of this structure were examined histologically. The calcar femorale is a condensation of cancellous bone. It is not affected by the reaming procedure but may play a role in guiding the reamer. This structure is separate from the calcar area described in relation to bone resorption after hip arthroplasty.