Iselin’s Disease

Traction epiphysitis of the base of the fifth metatarsal

•Disease occur in young adolescents - At the time of appearance of the proximal epiphysis of the fifth metatarsal.

•It is a small, shell-shaped fleck of bone oriented slightly obliquely with respect to the metatarsal shaft and located on the lateral plantar aspect of the tuberosity.

•Anatomic studies have shown that this bone is located within the cartilaginous flare onto which the peroneus brevis inserts.

•It usually is not visible on anteroposterior

or lateral radiographs but can be seen on the oblique view.

•It appears in girls at about age 10 years and in boys at about age 12 years; fusion occurs about 2 years later.

Clinical Presentation

•Iselin disease causes tenderness over a prominent proximal fifth metatarsal.

•Weight bearing produces pain over the lateral aspect of the foot.

•Risk Factor : Participation in sports requiring running, jumping, and cutting, causing inversion stresses on the forefoot

•The area over tuberosity is larger on the involved side, with soft-tissue edema and local erythema.

•The area is tender to palpation at the insertion of the peroneus brevis.

•There is resisted eversion and extreme plantar flexion.

•Dorsiflexion of the foot elicit pain.

Radiographic finding

•Oblique radiographs show enlargement and often fragmentation of the epiphysis and widening of the cartilaginous-osseous junction.

•Technetium-99m bone scanning shows increased uptake over the epiphysis.

•Nonunion of the fifth metatarsal has been reported in several adults as a result of Iselin disease and failure of fusion of the epiphysis.

Differential Diagnosis

•Fracture

•Os vesalianum, a sesamoid in the peroneus

Treatment

•Treatment is aimed at prevention of recurrent symptoms.

•For acute symptoms, initial treatment should decrease the stress reaction and acute inflammation caused by overpull of the peroneus brevis tendon.

•For mild symptoms, limitation of sports activity, application of ice, and administration of NSAID medication usually are sufficient.

•For severe symptoms, cast immobilization may be required.

•Occasionally, for chronic symptoms, an arch support that wraps around the base of the fifth metatarsal is used.

•Internal fixation of the epiphysis is not indicated.