Stress or march fractures were first recognized as an entity in 1855 by Breithaupt (1). Since then, these fractures, which are variously referred to as march, stress, insufficiency, fatigue, and pseudo-fractures, have been described in many bones throughout the body, particularly in the lower extremities. They are most commonly seen in the metatarsals, tibia, and fibula. Stress fractures of the calcaneus are less frequently reported. They are mentioned by Shanks and Kerley in their text (3), and Watson-Jones considers them in passing, quoting Asal, who reported GOO stress fractures from German Army hospital records during World War II, of which 0.6 per cent (4 cases) were of the calcaneus (4). Hullinger in 1944 submitted the only relatively extensive series which we have been able to find in the literature (5)—53 cases. Our experience has been that, although this entity is essentially unknown to most military and civilian physicians, it is not as infrequent as is generally believed, particularly among mil...