Medially based fixator corrects postop calcaneal fracture misalignment

The fixator captures laterally placed osteosynthesis constructs and pushes the construct and the tuber out of varus malalignment.

Using a medially based external fixator can help correct varus malalignment following operative management of intra-articular calcaneal fractures. The device can also promote better outcomes, according to a California-based surgeon.

“Restoration of height, width, length and alignment is paramount to ensure maximized patient outcomes and for potential salvage outcomes,” said LCDR Mark Thomas Gould, MD, of the United States Navy Medical Center in San Diego. Gould discussed a new technique for correcting varus malalignment at the American Orthopaedic Foot and Ankle Society 21st Annual Summer Meeting in Boston.

Gould explained the technique as taught to him by Stephen Benirschke, MD, of Harborview Medical Center in Seattle. The use of a medially based tripod external fixator “captures the laterally placed osteosynthesis construct and pushes the construct and the tuber out of varus malalignment,” he said.

Case studies

One case Gould described involved a 48-year-old women with a joint pression variant intra-articular calcaneus fracture caused by a fall from a golf cart. She was initially treated with a laterally based external fixator, but seven months postoperatively she complained of pain in the subtalar joint and in the weight-bearing lateral aspect of her foot.

“A complex intra-articular osteotomy and the varus correction was limited by severely contracted medial soft tissues,” Gould said. Physicians then placed a medially based external fixator, which corrected the malalignment and aided the bony healing. Five years postoperatively the patient is now pain free.

The second case he presented focused more on using the technique in the acute phase. A 63-year-old man suffered a myocardial infarction while flying his private airplane and sustained numerous fractures in the crash, including bilateral calcaneal fractures.

Physicians initially implanted a laterally placed calcaneus plate. Gould noted that, in this case, it is important to restore coronal alignment “because he had a significant peroneal nerve injury, and he had no lateral compartment motor function and just trace anterior compartment function.” Giving him the best alignment possible would allow him to start rehabilitation sooner, Gould said.

The technique worked in this case as well, correcting his alignment and allowing the bones to heal, he added.

There are a number of implants and screws which can accomplish this, but “when you’re capturing a 3.5 mm screw hole, you get the best interference fit if you use a Zimmer 5.5 mm by 130 mm locking bolt,” he said, noting that the tripod frame should be based off the anterior medial tibia for best results.

“This is a technique that is worth knowing about, when you have to overcome unacceptable coronal plane varus malalignment,” Gould said.

For more information:
Gould MT, Moore J, Bevan W, Benirschke S. Correcting varus malalignment following open treatment of intra-articular calcaneus fractures: a technique using a medially based external fixator. Presented at the American Orthopaedic Foot and Ankle Society 21st Annual Summer Meeting. July 14-17, 2005. Boston.