Curriculum · Musculoskeletal / Orthopedic / Rheumatology
Proximal fifth metatarsal fracture and metatarsal stress fracture
What it is
A stress fracture in the proximal fifth metatarsal is particularly prone to nonunion and to completion of the fracture, which makes it the high-risk one. Most stress fractures of the metatarsals occur distally instead, and treatment of the more common second and third metatarsal stress fractures is relatively straightforward. A proximal fifth metatarsal metadiaphyseal fracture can also occur suddenly, when all the weight is put on the lateral portion of the foot while on tiptoe.
Causes and risk
Metatarsal stress fracture belongs to athletes, military recruits and a sudden increase in activity.
How it presents
The stress fracture has an insidious onset of forefoot pain that worsens with activity, with localized tenderness over the metatarsal shaft; the exam clue is a female athlete with forefoot pain. An acute proximal fifth metatarsal fracture instead gives pain felt immediately, so that the patient cannot bear weight, and a foot that is slightly edematous with a small amount of ecchymosis.