Periarticular distal tibial infected nonunion, ankle salvage with bone

2022-06-25 09:06:18 By : Mr. Jason Ma

This case outlines a staged approach to a patient status post open reduction, internal fixation (ORIF) of a tibial Pilon fracture with infection, bone loss and soft tissue compromise. The soft tissue management in this case dictates the approach and extent for reconstruction. Our plan involved careful exposure through compromised soft-tissue, removal of all nonviable tissue (bone and hardware) and stability (circular ring external fixation). The decision for ankle salvage versus arthrodesis is made based on the viability of the small tibial plafond segment and the condition of the tibio-talar joint. Residual limb length discrepancy was corrected through an integrated fixation method, lengthening with a Taylor-Spatial Frame (TSF) and then insertion of an intramedullary nail, as part of the second stage reconstruction.

This is a 42-year-old male who fell from a construction scaffold eight months prior to presentation in our clinic. The patient suffered a type IIIb Pilon fracture that was treated with external-fixation and a limited ORIF. Postoperatively, at the outside institution, the patient developed a wound infection with dehiscence that required repeat debridements. One-month post injury, the patient required an abdominal free-flap and hardware revision to provide adequate soft tissue coverage. A repeat ORIF was attempted at the time. This resulted in repeat wound infection and wound dehiscence. The patient presented to our clinic with active infection, wound breakdown and a vacuum-assisted closure (VAC) device on his leg.

This complex reconstruction was divided into two stages. We also discussed with the patient a salvage option, which would have been ankle arthrodesis. Stage one’s goals were to perform a meticulous ankle debridement and obtain reliable deep tissue cultures and pathologic specimens. A TSF would provide the stability. Dead space management after debridement would be managed with rapid (2 mm per day) shortening of the articular block to the distal metaphysis. The TSF would also correct the rotational and equines deformity. Finally, residual limb length would be corrected with a proximal tibial and fibula osteotomy and application of TSF.  Lengthening would be performed using the Lengthening and then Nailing (LATN) technique.

Nonviable bone must be excised, potentially leaving a relatively small articular segment. If the tibial plafond is viable and good joint congruity exists, the ankle joint can be salvaged. 1.8 mm Olive wires are used to secure the segment and mechanical stability is augmented using a foot ring. The geometry of the bone resection is important. Flat cuts are mandatory. Soft tissue handling must be gentle and a plastic surgery colleague is invaluable in choosing skin incisions as well as re-elevating soft tissue flaps. Spanning the ankle provides improved stability to the distal segment and can be used to correct ankle contracture or manage drop-foot.

Fellow, Limb Lengthening and Complex Reconstruction Service, Hospital for Special Surgery