|Beitragstitel||Medial swivel dislocation of the talonavicular joint|
Medial swivel dislocation, a variant of a subtalar dislocation is uncommon. We present a case successfully treated with this rare lesion.
A 54 years old female presented one week after a low energy trauma to her left mid foot. She had pain, swelling around the ankle, and was unable to bear weight on the left foot. Clinical examination revealed moderate swelling and tenderness in the mid foot region. Plain radiographs and CT-scan showed a talo-navicular dislocation with osseous impaction of the head of the talus. Open reduction and fixation was performed. The osteochondral lesion of the talus was fixed with two solitary 1.5 mm cortical screws and a temporary talo-navicular arthrodesis with a 2.0 mm plate was performed. The patient was allowed to walk with partial weight-bearing with a short leg cast for 8 weeks. After 3 months, the plate was removed; the patient received physical therapy for improvement of proprioception and muscle force. After one year, the patient was completely free of pain; the mobility of the subtalar joint and the muscle forces were symmetric. On the radiographs a small collapse of the head of the talus without clinical consequence was detected.
The described injury is characterized by a dislocation of the talo-navicular joint. The calcaneo-cuboid and the subtalar joints remain intact. During accident, the foot makes a typical rotational movement consisting in a pure supination and adduction without any additional inversion or eversion. The axis of rotation is the interosseous talo-calcaneal ligament which remains intact. This lesion is very rare and there are only 3 cases reported in the literature. Diagnosis can be easily missed. Thus, careful analysis of all plain radiographs is mandatory, and imaging has to be completed with a CT-scan.