Distribution and natural history of stress fractures in U.S. Marine recruits.

In a prospective study of stress injuries of the lower extremities of U.S. Marine recruits, we derived a frequency distribution of stress fractures. The most frequently fractured bone was the tibia (73%), while the single most common site was the posterior calcaneal tuberosity (21%). The natural history of stress fractures by scintigraphy and radiography has been outlined, showing the evolutionary changes on either study as a universal progression independent of injury site or type of stress. An identical spectrum of changes should be present within any group undergoing intense new exercise. The frequency distribution of stress fractures should be a function of differing forms and intensities of exercise, therefore, our figures should not be applied to other groups. We used the presence of a scintigraphic abnormality at a symptomatic site as the criterion for diagnosis of stress fracture. Since the distribution of skeletal radiotracer uptake is directly dependent on local metabolic activity, it is expected that a focal alteration in bone metabolism will result in a scintigram approaching 100% sensitivity for the abnormality (9). In the proper clinical setting, the specificity should approximate this figure; however, a focal, nonstress-related bone abnormality which has not manifested any radiographic change, such as early osteomyelitis, could result in a false-positive examination. Specificity cannot, therefore, be accurately determined without an actual determination of the pathologic changes within the bone, necessarily involving biopsy. In summary, we believe that we have established bone scintigraphy as an early and accurate means for the detection of lower extremity stress fractures, even in the absence of radiographic findings (6). We feel that a focally abnormal scintigram, in the proper clinical setting, establishes the diagnosis of stress fracture, with radiography to be performed at the time of initial work-up only to rule out a non-stress injury (such as complete fracture, fibrous dysplasia, osteomyelitis, primary bone tumor).

Renal devitalization using 95 per cent ethyl alcohol.

Preoperative embolization of renal arteries with solid material before nephrectomy is a standard procedure for the treatment of renal cell carcinoma. However, it often is difficult to use these materials and sometimes special equipment is required. We have used 95 per cent ethyl alcohol in 3 patients to devitalize kidneys with tumors. Our results show 95 per cent ethyl alcohol to be safe, effective and easy to use. When combined with epidural anesthesia alcohol embolization is well tolerated by the patient, and its destructive effect is complete and limited to the selected organ.

Survival of red blood cells in rabbits after acute administration of unlabeled stannous pyrophosphate: Concise communication.

We investigated the possibility that acute administration of unlabeled stannous pyrophosphate may adversely affect red blood cells in the rabbit. Our method was similar to the in vivo labeling of RBCs with technetium-99m for blood-pool scanning. The investigation showed that dosages recommended in the literature produce no demonstrable difference between pre- and postdose RBC survival, which strongly suggests that the stannous content of the pharmaceutical is not harmful to red blood cells.