Failed Subtalar Fusion

Coalitions

Description of patient (type of occupation, indication of age, intensity of sport):

42 year old healthy healthy female

History and previous treatment:

History of ankle pain since more than 2 years. No trauma in the past. Has undergone two open subtalar fusion operations left side in other hospital.

Current complaints:

Constant pain when she is walking. Pain in rest and at night as well.

Physical examination:

left hindfoot stiffness and swelling. Healed incision lateral. Pain over protruding screw medial.

Radiology:

X-ray:
In the x-ray the fusion seems to be healed but CT scan shows nonunion and misplaced screw.

Additional investigation (CT/MRI):
[Picture 1, 2, 3, 4 + 5]
CT scan shows a nonunion after two open subtalar fusion attempts and misplacement of one screw. I don't have the images from the first fusion. After report of the patient allograft bone was used in the second operation.

Images:

Case summary:

Two failed subtalar fusions on the left side.

Question(s) to this case:

What are your tratment options. From my view I would remove hardware and do extensive debridement and bone grafting from iliac crest. Fixation with cortical struts?

Expert:

I would recommend to remove the screws and perform subtalar arthroscopic fusion by means of a 2 portal hindfoot approach. A bone graft should normally not be needed. Remove enough dead bone to get to bleeding bone surface. If you feel the gap is to large apply autologous bone graft. This can also be performed arthroscopically. Fix with 2 lag screws through calcaneus.

Current problem is that lagscrew missed the calcaneus and does not give compression.
Technical note: Removal of this screw is technically demanding.. It might be wise to advance the screw and remove is by separate incision through the heel in retrograde fashion

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