Review Question - QID 219868

The patient has a stress reaction of the third metatarsal shaft, which should be appropriately assessed with a complete metabolic workup to evaluate for systemic risk factors that may contribute to stress reactions.

Stress reactions of the metatarsals can be seen as overuse injuries in athletes and most typically involve the second metatarsal shaft. Over time, with repeated cycles of loading, accumulation of such injuries can lead to macro-structural failure and frank fracture. Thus, it is essential to rule out concomitant risk factors such as metabolic disorders (i.e., hypothyroidism, amenorrhea, etc.) that can predispose to structural weakness. In particular, the specific risk triad involving repeated stress, low bone mineral density, and dietary restraint has been reported in female athletes and significantly increases the risk of fracture. A complete workup, therefore, should include basic laboratory values, menstrual history (in females), and when necessary a DEXA scan.

Welck et al. provide a review of stress fractures of the foot and ankle. The authors note that an awareness of these fractures is important, as the diagnosis is frequently missed and appropriate treatment is delayed. They conclude that late identification can be associated with protracted pain and disability and may predispose to non-union, particularly in fractures of hallux sesamoids, the mid-tibial shaft, base of fifth metatarsal, and tarsal navicular.

Kahanov et al. reviewed the diagnosis, treatment, and rehabilitation of stress fractures in the lower extremities in runners. The authors note that stress fractures account for between 1% and 20% of athletic injuries, with 80% of stress fractures occurring in the lower extremity. They conclude that the most difficult aspect of stress fracture treatment entails mitigating internal and external risk factors, making it imperative that practitioners address ongoing risk factors to minimize recurrence.

Figures A and B represent T2 coronal and axial MRI images of the foot showing bone marrow edema and soft tissue swelling consistent with a third metatarsal stress reaction without overt fracture.

Incorrect Answers:
Answer 1: Immediate return to play without a period of immobilization or further workup may lead to overt fracture.
Answer 2: There is no evidence for the use of bone stimulators in the setting of stress reactions.
Answer 3: The MRI findings are consistent with a stress reaction, not with a bone or soft tissue mass.
Answer 5: Stress fractures of metatarsals 2-4 are most often treated successfully with immobilization alone.