The classification systems of stress fractures: a systematic review.

ABSTRACT

BACKGROUND: Stress fractures of the upper and lower extremity are troublesome overuse injuries in athletes and nonathletes alike. These injuries have a broad spectrum of severity and prognosis. We performed a systematic search of the literature, which revealed multiple classification systems; however, we did not uncover a general system that offered both validated radiographic and clinical parameters. METHODS: A literature search was conducted using Ovid/Medline, Embase, and the Cochrane Library, with publication dates ranging from 1960 to December 2009. Inclusion criteria included all studies and review articles regarding stress or fatigue fractures and their classification. RESULTS: Forty-three studies and/or articles were identified for this review. Of these articles, 27 classification systems were referenced. Sixteen of the systems were applicable to any injury location, and 1 applied to specific bones (femoral neck, tibia, tarsal navicular, pars interarticularis, and fifth metatarsal). Four classification systems were referenced more often than others. Of the classification systems, 11 were based on radiographs alone, while the other 16 used a variety of radiographic modalities, including radiographs, bone scans, computed tomography, ultrasound, and magnetic resonance imaging. CONCLUSION: There are many different stress fracture classification systems in the literature. These systems employ various imaging modalities, but few include clinical parameters. Many are site specific. Of those that are widely applicable, no general classification system has been shown to be reproducible, easily accessible, safe, inexpensive, and clinically relevant. A gold standard classification system for describing stress fractures has yet to be determined.