Combined ankle distraction arthroplasty and supramalleolar osteotomy were planned. The osteotomy was stabilized with circular external fixation. A Taylor Spatial Frame (Smith & Nephew, Memphis, TN) was selected for its ability to correct deformity with great accuracy in a gradual fashion. An open arthrotomy and microfracture of the talus was also performed with injection of autologous iliac crest, bone marrow aspirate concentrate. Hinges were used to provide articulated distraction. The joint distraction was applied acutely in the operating room to 5 mm. The osteotomy of the fibula and tibia was gradually angulated to allow for an accurate bony realignment utilizing distraction osteogenesis. The foot ring would be left in place for 3 months and then removed. The tibial rings would be removed at 4 months when the osteotomy was fully healed.

Articulated distraction: A hinge is used to preserve ankle range of motion during the 3-month treatment period.

Distraction osteogenesis: The gradual movement of an osteotomy results in bone formation at the osteotomy site. This principle was used to provide an angular correction. The valgus deformity could have been corrected acutely with a plate but would have required bone grafting or limb shortening. The accuracy of acute correction with internal fixation is less reliable than with adjustable external fixation.

See Fig. 3.