- See:
Avascular Necrosis and Salvage of Talus Fractures
- Discussion:
- displaced frx of talar neck with dislocation of body of talus from both
subtalar joint and ankle joint;
- when body dislocates, it is usually found on posterior medial aspect adjacent to the Achilles tendon;
- body fragment rotates around intact deltoid ligament fibers to lie in soft tissues w/ frx surface pointing laterally and cephalad;
- in this location, there can be compression of the neurovascular structures, and care must be taken
when approaching by open means the dislocated body of the talus;
- talocalcaneal ligament is ruptured when there is dorsal displacement of the distal fragment;
- after rupture of this ligament, it is difficult to control distal talar neck fracture by closed means;
-
Radiographic Evaluation: Hawkins Sign:
- Treatment:
- surgical approaches:
- medial malleolar osteotomy;
- associated frxs of
medial malleolus facilitates reduction because malleolus & attached
deltoid ligament can be retracted distally, & ankle
mortise can be opened to allow reduction of talus;
- frequently deep fibers of deltoid lig remain attached to talar body;
- these fibers is not be released surgically because they may carry only remaining
arterial supply to the body;
- it is preferable to osteotomize the medial malleolus and reflect it distally to facilitate reduction rather than cutting intact
deltoid ligament;
- technique:
- anterior capsule at medial axilla is exposed;
- posterior tibial tendon sheath is incised posteriorly, exposing the posterior tibial tendon (retract the tendon posteriorly);
- drill two holes into the medial malleolus inorder to accomodate post osteotomy screw placement;
- care is taken to avoid trauma to the deltoid ligament;
- at a point, 1 cm proximal to the joint line, a saggital saw is used to make a transverse cut thru the tibial cortex, parallel to the plafond;
- this cut extends to the level of the axilla;
- osteotome is then used to complete the ostetomy (from the axilla to the transverse cut), in an anterior to posterior direction;
- reduction:
- facilitated, w/ insertion of calcaneal traction pin;
- inorder to reduce talar body into the mortise, foot is dorsiflexed w/ heel translated anteriorly;
- the foot is then everted, and talar body translated medially, and finally is plantar flexed;
- fixation:
- retrograde K wires are placed thru frx & out posterior lateral aspect;
- cannulated screws are used thru posterior-lateral aspect using wires;
- Complications:
- vast majority of these patients will have a poor result (infection, AVN, DJD);
-
avascular necrosis and salvage of talus fractures
- AVN: may occur in upto 90 % of patients;
