Review Question - QID 3808

Figure A shows an avulsion fracture of the calcaneal tuberosity. Immediate open reduction and internal fixation is required to prevent wound complications.

Displaced avulsion fractures of the calcaneal tuberosity should be managed urgently to prevent necrosis of the soft tissues overlying the heel. In these injuries, the Achilles tendon is securely attached to the fractured tuberosity. Urgent closed reduction and casting is usually not possible due to the power and proximal pull of the triceps surae. Surgical fixation is required. The best treatment modality is open reduction and bone-to-bone fixation with screws. Closed reduction and percutaneous pinning fixation is not strong enough to provide a stable fixation of the tuberosity.

Lui reported on avulsion fractures of the bony insertion of the Achilles tendon at the calcaneus. He stated that screw fixation alone is not sufficient for repair of these injuries. His technique involved two suture anchors used capture the small bone fragment to the calcaneus. This allowed for the pull of the triceps surae to be neutralized and early physical therapy.

Hess et al. looked at a case series of calcaneal tuberosity avulsion fractures that were treated in a delayed fashion. All three patients with posterior tuberosity calcaneal avulsion fractures developed skin necrosis because of a delay in treatment.

Figure A shows a displaced posterior tuberosity calcaneal avulsion fracture. Illustration A shows skin breakdown overlying the posterior tuberosity calcaneal avulsion fracture.

Incorrect Answers:
Answer 1: The amount of displacement is an indication for fixation, however urgent treatment does not improve union rates with these fractures.
Answer 2: Tuberosity calcaneal avulsion fractures rarely disrupt the blood supply to the avulsion fragment and are not associated with avascular necrosis.
Answer 3: Plantar flexion weakness is a known complication of these injuries despite many treatment options.
Answer 4: Ankle stiffness is most commonly related to surgical fixation methods and post-operative immobilization and delayed rehabilitation.