TaloNavicular Dislocation: Treatment with Stryker Orthopedics External Fixator

By Jay Lieberman, DPM
Director of Podiatric Residency Education
Northwest Medical Center
Margate, Florida

 

Case Presentation

A 48 year old female was seen in our emergency room with pain and swelling in her right foot, two hours after falling from her bicycle while riding at a high speed.   The patient was thrown forward causing her foot to fold under the weight of her body.  She described the mechanism of injury as though the pulp of her hallux was reaching toward the heel of her foot.   When compared to the contra lateral side, the injured foot appeared to take on a new contour.  A bit of a dorsal prominence was seen along the dorsal lateral aspect of the foot.  The first ray was in equinus and the medial column appeared shortened.

The patient's neurovascular status was intact.  Movement was limited, and pain was a 10/10.  X rays demonstrated a plantar lateral dislocation of the talar head.
 

CT scan confirmed the dislocation and also revealed an impaction of the fractured navicular bone upon the dorsal aspect of the anterior talar process. Communition was seen as well.
 

Unaffected limb Affected limb Affected limb

The calcaneus, and navicular, along with the rest of the foot was medially displaced with respect to the leg.
 

Treatment Considerations

Reduction of dislocations of this type should proceed as quickly as possible to relieve pressure on vital structures. The incidence of a subtalar joint dislocation is estimated to be approximately 1% of all dislocations. The medial dislocation represents 84% of subtalar joint dislocations. 68% of patients are found to have associated osteocartilagenous joint damage. Injuries to adjacent tendons, arteries or nerves are commonly seen. On occasion, a tendon can become entrapped within the affected joint, causing loss of function and potentially preventing closed reduction of the dislocation. As in most dislocations, reduction maneuvers involve an exaggeration of the original injury followed by reversal of the process.

Closed Reduction

The thigh was suspended from a padded knee holder. The knee was flexed 90