Fracture dislocation of the ankle with posterior tibial tendon entrapment within the tibiofibular interosseous space: A case report

Abstract

In rare cases of ankle fracture dislocation, the posterior tibial muscle tendon (TP tendon) is incarcerated between the tibia and fibula, thereby impeding reduction. Here we describe a case that presented with such a condition, in which ankle reduction was achieved and surgical repair of the incarcerated TP was delayed. The subject was a 30-year-old male who sustained a fracture dislocation of the left ankle (AO:44-C1.3) in a motorbike accident. After repairing the ankle dislocation, external fixation was performed and osteosynthesis was conducted 10 days after the injury. Plate fixation for the fibula fracture and tight rope fixation for the separation between the tibia and fibula were performed; however, internal fixation for the medial malleolus fracture was delayed because the skin on the medial side of the ankle was in poor condition. One month after the injury, osteosynthesis of the medial malleolus was performed, and the TP tendon was identified in the fracture site. After removing the incarcerated tendon, good reduction of the medial malleolus was achieved, and thus, internal fixation and wound closure could be performed. Re-examination revealed that the TP tendon had an abnormal course. After 3 months, upon re-exposing the entire length of the TP tendon, the TP tendon was incarcerated between the tibia and fibula. To date, although several cases have been reported regarding TP tendon incarceration caused by fracture dislocation of the ankle, no study has reported the anatomical repair of the ankle, regardless of tendon incarceration. In our case, rotational displacement of the medial malleolus fracture remained when the second surgery was completed; however, the presence of some type of incarcerated tissue was suspected. Because leaving the incarcerated TP tendon untreated can cause irreversible long-term complications, early anatomical repair is recommended.

Irreducible Fractures and Dislocations of the Ankle Associated With Entrapment of the Posterior Tibial Tendon Within the Tibiofibular Interosseous Space: A Case Series and Literature Review

“…Most recently, Sato et al 13 described a multistage case in which recognition and reduction of a PTT trans-syndesmotic dislocation was achieved only after a third attempt at open reduction involving full operative exposure of the PTT, approximately 3 months after the initial injury. The abnormal tendon course was revealed via CT and MRI in the setting of the patient having difficulty with ankle inversion.…”

“…8 As a consequence of unrecognized diagnosis, published postoperative sequelae have included significant long-term stiffness, extensive soft tissue compromise requiring coverage, as well as equinovarus and clawtoe deformity secondary to ischemic deep posterior compartment contracture. 1,6,13,17 In this case series, recognition of trans-syndesmotic PTT dislocation was achieved at the time of initial open definitive fixation, in 1 case following external fixator removal and planned open reduction and internal fixation (ORIF), allowing for appropriate anatomic reduction and avoidance of additional operative procedures. This case series contributes to a limited body of literature describing and facilitating prompt recognition of this rare injury pattern and reinforces previous recommendations advocating for the benefits of early diagnosis and appropriate treatment.…”

“…9 However, there are descriptions of a dislocation of the PTT around the posterior malleolus with subsequent passage of the tendon posteriorly to anteriorly through a concomitantly ruptured and widened tibiofibular syndesmosis. 1,2,5,6,8,[10][11][12][13]17,18,20 In some instances, the tendon even extends proximally into the interosseous membrane. In such instances, the PTT may course from lateral to medial along the anterior aspect of the tibia.…”

“…8 As a consequence of unrecognized diagnosis, published postoperative sequelae have included significant long-term stiffness, extensive soft tissue compromise requiring coverage, as well as equinovarus and clawtoe deformity secondary to ischemic deep posterior compartment contracture. 1,6,13,17…”

Posterior tibial tendon entrapment after fracture dislocation of the ankle

“…In rare cases of ankle fracture dislocation, the posterior tibial muscle tendon (TP tendon) is incarcerated between the tibia and fibula, preventing reduction. 1 Tendon entrapment of the posterior tibial tendon can be responsible for inadequate reduction of the medial ankle. However, deltoid ligament and neurovascular bundle have also been reported in published studies.…”