Freiberg's infraction.

To cite: Lin H-T, Liu AL-J. BMJ Case Rep Published online: [please include Day Month Year] doi:10.1136/ bcr-2013-010121 DESCRIPTION The patient is a 16-year-old girl who visited the clinic and presented with a 3-month history of right foot pain. She described the pain as constant and dull, and exacerbated with walking. No traumatic history was noted. Physical examination revealed evident swelling and tenderness near the second metatarsophalangeal (MTP) joint. Radiograph of the right foot revealed flattening of the second metatarsal head with subchondral sclerosis and fragmentation within the joint (figure 1). In addition, MRI demonstrated hyperintense signals on T2-weighted images (figure 2A,B). Based on clinical and radiological information, Freiberg’s infraction was diagnosed and the patient was treated conservatively with rest and activity modification. After 2 months of follow-up, she was walking pain-free. Freiberg’s infraction is a rare disease characterised by osteonecrosis of the metatarsal head primarily affecting the second metatarsal. With its multifactorial aetiology, the condition predominantly occurs in teenagers with a 5 : 1 female predilection. Patients often present with pain and swelling around the MTP joint. The radiographic appearance is typical with flattening of the second metatarsal head, increased sclerosis and loose body formation within the joint. MRI is useful in its diagnosis, as T2-weighted images often show increased signal intensity in the metatarsal head. Since most cases are self-limited, conservative therapy in the form of rest, crutches or casting may be adequate. Surgery is rarely indicated and is reserved for patients who fail