- Stability of the foot is dependent on both the medial and lateral longitudinal columns; injuries to a single column alone are extremely rare.
- Midfoot fractures that are recognized and treated early have generally favorable outcomes compared to those identified in a delayed fashion.
- The most frequent complication of navicular dislocation is AVN, which is said to occur in as many as 25% of cases.
- Many specialists agree that navicular dislocations are best treated with open reduction.
- Ultimately, the goals of surgical intervention are to minimize pain and to establish stability of the plantigrade foot.
Traumatic dislocation of the tarsal navicular (especially without a navicular body fracture) is uncommon.1 The regional anatomy and ligamentous architecture confer stability to the midfoot.2-6 Navicular dislocation is part of a complex disruption involving structures in the adjacent column.6
Navicular dislocation has been associated with several bony and soft-tissue injury patterns, including comminuted intra-articular fracture of the calcaneus and associated calcaneocuboid joint subluxation; fracture and subluxation of the calcaneocuboid joint; fracture-dislocation of the calcaneocuboid joint with fractures of the third and fourth metatarsals; and a combination of fractures of the intermediate cuneiform, the second through fourth metatarsals, and the cuboid.4–11 In this article, we report a case of open complete navicular dislocation with talar head fracture and associated subtalar and calcaneocuboid subluxations in a 45-year-old man. The injury was managed with open reduction and stabilization with Kirschner wires (K-wires), which later required naviculocuneiform and intercuneiform fusion for posttraumatic avascular necrosis (AVN). The patient provided written informed consent for print and electronic publication of this case report.
A 45-year-old man sustained blunt trauma to the right foot in a high-speed head-on collision. He was hemodynamically stable with isolated complaints of pain in the foot. Physical examination revealed a grossly open 10-cm wound extending from the heel pad medially to the dorsal surface of the navicular. The navicular was clearly visible through the wound.
Plain radiographs of the foot showed complete medial dislocation of the navicular with complete disruption of all 3 naviculocuneiform joints (Figures 1A-1C).
On day of presentation, the patient was taken to the operating room for irrigation, débridement, reduction of the joints, and primary closure of the right foot wound. Minimal contamination was noted. Attempted gentle reduction maneuvers included distraction, adduction, and pronation of the forefoot with concomitant lateral pressure on the navicular.
An especially prominent medial navicular was noted on postreduction films. Initially, this suggested inadequate reduction of the naviculocuneiform joints, but, on close radiographic examination of each naviculocuneiform joint and imaging of the contralateral foot, we determined that the prominence represented a type III accessory navicular, also known as a cornuate navicular. Contralateral imaging showed an identical and asymptomatic medial prominence.
After surgery, the patient was made non-weight-bearing in a splint, received intravenous antibiotics for 48 hours, and was discharged shortly thereafter. Radiographs at 3 and 6 weeks after injury showed maintenance of the reduction. K-wires were removed at 6 weeks. The patient was advanced to partial weight-bearing at 6 weeks and to full weight-bearing at 3 months.
Over succeeding months, the patient developed pain accompanied by significant midfoot deformity and was found to have navicular collapse consistent with AVN and posttraumatic arthritis (Figures 4A, 4B).
Twenty-four months after fusion, the patient was fully ambulatory with no significant discomfort or disability.