Stress fractures of the calcaneus.

Abstract

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 military personnel. We are planning further publication in terms of the frequency of calcaneal stress fractures in relation to similar lesions of other bones of the lower extremity. We feel, however, that the significance and incidence of the condition warrant the present report. Our attention was first called to stress fractures of the calcaneus in January 1958, when our first case was observed. We have since discovered 8 additional cases, 3 of which were bilateral. This brings our total to 12 within five months. The incidence of bilateral occurrence is in agreement with Hullinger's figure of 33 per cent. During the entire calendar year 1957 we had not recognized a single instance of this lesion, but a review of the films from that period demonstrated 1 case in retrospect, bringing our total to 13. Failure to recognize this case originally and the small number of cases seen formerly we attribute primarily to the lack of awareness of the entity on the part of both radiologists and clinicians. The earlier cases in our series came to the attention of our X-ray Department only after several days or weeks of physiotherapy directed toward what was clinically diagnosed as a tenosynovitis of the Achilles tendon. We wonder, therefore, if many other cases have so masqueraded and have evaded radiographic examination. Since our first several cases, the index of clinical suspicion at this establishment has been much higher; the overall number of os calcis examinations has been far greater, and the number of stress fractures of the calcaneus recognized correspondingly raised. Clinical Material The clinical material utilized in this study was the recruit population at the U. S. Marine Corps Recruit Depot in San Diego. About 8,700 men in their late teens and early twenties have been processed at this base between the time of discovery of the first case of stress fracture of the calcaneus and the submitting of this report.