Freiberg's infraction: diagnosis and treatment.

Freiberg's infraction is a condition of cartilage degeneration of the lesser metatarsal heads. Adolescent females are the "textbook" patients but both males and females may present with this condition later in life. The second and third metatarsals are the most commonly affected, while involvement of the fourth and fifth is rare. The incidence is higher in females than in males. The pathophysiology is unknown, but studies suggest a combination of vascular compromise, genetic predisposition, and altered biomechanics. Diagnosis is made clinically and imaging is used to confirm. Early in the process, radiographs are normal however bone scans may demonstrate a photopenic center with a hyperactive collar and magnetic resonance imaging can reveal hypointensity of the metatarsal head. As Freiberg's infraction progresses, radiographs show a flattened and fragmented metatarsal head. Nonoperative treatment is based on decreasing foot pressure and unloading the affected metatarsal. Spontaneous healing with remodeling may occur in early stages of the disease. Operative options are dorsal closing wedge osteotomies, osteochondral transplant, and resection arthroplasty. Currently, we do not understand this disease sufficiently to prevent its occurrence. Outcomes of nonoperative and operative management are good to excellent and most patients are able to return to previous activity.