Learning objectives
1) hindfoot joint dislocations represent severe ligamentous injuries which substantially compromize both foot stability and integrity;
2) familiarity with peritalar dislocations of the hindfoot is crucial to avoid potentially devastating sequelae when overlooked;
3) recognition of peculiar interferences of hindfoot joint alignment and subtle osseous avulsions is prerequisite to identify substantial trauma to these joints.
Background
Hindfoot fracture-dislocations including the upper ankle joint represent high-energy impact injuries in most cases.
In the presence of overt fractures,
a hindfoot injury will be readily recognized.
However,
diagnostic problems will arise in such cases where sole and uncommon hindfoot dislocations are missed because of spontaneous repositioning.
In particular,
this is true for rare peritalar dislocations.
Imaging findings OR Procedure Details
In the following,
five types of hindfoot and ankle fracture-dislocations will be discussed:
1) trimalleolar upper ankle fracture-dislocation: plain radiograph (Fig.
1) clearly shows a severe fracture-dislocation of the upper ankle joint in a 20-year-old lady,
came off from horseback.
In this case,
a substantial posterolateral joint-forming fragment was failed to be repositioned because of unawareness (lack of pre-operative computed tomography) (Fig.
2).
Revision operation was therefore required.
2) Talar dislocation,
i.e.
luxatio pedis cum talo: a 68-year-old man fallen from stairs suffered a rare...
Conclusion
Familiarity with hindfoot fracture-dislocation injuries is crucial to avoid misinterpretation of unusual osseous fracture patterns and malalignments.
Awareness of underlying dislocation mechanisms is of superior importance to identify and to classify hindfoot fracture-dislocations because of specialized and optimized surgical procedures.
References
1. Fotiadis E et al.: Closed subtalar dislocation with non-displaced fractures of the talus and navicular...
Case J 2009; 2: 8793.
2. Sharifi SR et al.: Closed total talus dislocation without fracture...
Case J 2009; 2: 9132.
3. Rhanim A et al.: Nonoperative tretmant of closed total talus dislocation without fracture...
J Clin Orthop Trauma 2014; 5: 172-175.
4. Jarraya M et al.: Radiographically occult and subtle fractures...
Radiol Res Pract 2013: doi 10.1155/2013/370169.
5. Milenkovic S et al.: Hawkins Typ III Fraktur...
(in German)...