Metatarsal Stress Fracture

Oblique radiographic view of the foot shows transverse fracture lines of the proximal diaphyses of the forth and fifth metatarsals (arrows). Note sclerotic bone ends, periosteal reaction and minimal widening of the fracture gaps (degree of sclerosis is more on the forth digit)

Facts

• Spontaneous fractures of normal bone that result from summation of stresses
• Most common lower-extremity stress fracture
• Originally termed "march fracture" (seen in military recruits). Now seen in ballet, football, gymnastics and basketball
• Most common site = shaft (at diaphysis or neck)
• Increased incidence in pes cavus and pes planus foot

Radiography

• Often negative in early phase. May see thickening of cortex and small periosteal reaction
• Later, a fracture line with sclerotic bone ends, periosteal reaction, widening of fracture gap will be shown. 
• Late phase, the bone ends involved are entirely sclerotic 

References:

Schepsis AA, Busconi BD. Sports Medicine, 2006.

Baxter DE, Porter DA, Schon L. Baxter's the Foot and Ankle in Sport, 2008.