Ankle Arthrodesis Using Ring External Fixation - Orthofix.com

Special Focus: Ankle Arthrodesis Using Ring External Fixation
FIGURE 17. Compression is applied through the tibiotalar
joint.
between the calcaneus and distal tibia is sufficient.
However, in patients with intact subtalar joints,
compression should only be applied across the
tibiotalar arthrodesis site. To accomplish this, a
fixed Bdistal ring block^ is applied to isolate the
talus from the calcaneus and protect the subtalar
joint. Through either extended connectors from the
foot frame or an additional intermediate ring, 1 or
preferably 2 thin wires are placed in the talus and
appropriately tensioned. Care must be taken to
ensure that the pins are indeed in the talus and do
not engage the malleoli (Figs. 16A, B).
14. Compression may be applied after all components
of the external fixator have been tightened, and all
thin wires have been tensioned. If the Steinmann pin
placed longitudinally for provisional fixation is
directly perpendicular to the arthrodesis site, then
it can be used as a Brail^ during compression. The
provisional fixation is typically removed at the end
of the case (Fig. 17).
FIGURE 18. Intraoperative fluoroscopy after compression.
Note the bending of the tensioned thin wires in the talus.
15. Intraoperative fluoroscopy is used to confirm
adequate bony apposition at the arthrodesis site
and proper pin position (Fig. 18).
16. If there is concern for inadequate compression or a
tendency toward varus malalignment at the tibiotalar
joint, consideration should be given to a fibular osteotomy,
if it was not already cut or resected during the
approach. We favor an oblique osteotomy, proximal
lateral to distal medial through a 2- to 3-cm incision.
17. The wires are appropriately cut and bent. Alternatively,
the pins can be cut flush with the external fixator.
However, if a wire needs to be tensioned later, leaving
a carefully bent residual wire allows for this.
18. Sutures are used to close any extension of the stab
incisions created for pin placement.
FIGURE 19. A and B, Example of Taylor Spatial Frame being
used for revision ankle arthrodesis that required posterior
translation of the talus in addition to tibiotalar compression.
Volume 5, Issue 3 157
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