Flexor digitorum profundus entrapment after closed treatment of a displaced Colles' fracture

Entrapment of the flexor digitorum superficials in the radius fracture site

Entrapment of the flexor tendon after fracture of both forearm bones is very rare. This report describes entrapment of the middle finger flexor digitorum superficialis (FDS) tendon alone in the radius fracture site. A 13-year-old boy fractured both forearms and had closed reduction and a long-arm cast. After the cast was removed he had full middle finger motion with the wrist flexed but was unable to extend the proximal interphalangeal or metacarpophalangeal joints and could extend only the distal interphalangeal joint of the middle finger with the wrist in the neutral or extension position. Entrapment of the middle finger FDS tendon was suspected. After surgical release of the FDS tendon at the fracture site the patient had good functional results.

Flexor tendon entrapment in ulnar shaft fractures

Entrapment of tendons in pediatric forearm fractures has been reported rarely and often is diagnosed months to years after the initial injury. Tendon entrapments are reported to occur more frequently distally than proximally. Two pediatric cases of proximal entrapment of the flexor digitorum profundus in an ulnar shaft fracture are reported here. Early diagnosis permitted surgical release and early restoration of full function. These cases emphasize the difficulty in diagnosing this rare condition in a young child and the need for careful digital range of motion examination under ideal circumstances, with pain and apprehension eliminated.