Cross-leg latissimus dorsi free flap with chimeric serratus anterior bridge for lower extremity trauma: Case report and reconstructive algorithm

Abstract

Gustilo Grade IIIB and IIIC open fractures of the lower extremity often involve complex wounds requiring bony fixation and soft tissue reconstruction. We present a case of a 32 year-old male who suffered a traumatic Gustilo Grade IIIB open fracture of the tibia and fibula with an extensive soft tissue defect. Reconstruction was first attempted with a turbocharged anterolateral thigh flap that failed due to venous thrombosis. Due to vascular injury, limited reconstructive options were available from the ipsilateral leg. Limb salvage was subsequently achieved with a chimeric cross-leg latissimus dorsi-serratus anterior (LD-SA) free flap based off the contralateral healthy leg, using the serratus for pedicle bridge coverage so that the latissimus could be fully used for defect coverage. Though not extensively described in the literature, this flap is a versatile reconstructive option for limb salvage in patients with Gustilo IIIB or IIIC injuries to the lower extremity.

Keywords: Cross-leg; Free flap; Free tissue; Lower extremity; Open fracture; Trauma.

Fig. 1

Right lower extremity clean wound after bony stabilization and serial debridements.

Fig. 2

Left thigh (flap donor site) with turbocharged ALT flap incised. Right leg (flap recipient site) with large, clean wound bed and exposed bone. ALT, anterolateral thigh.

Fig. 3

Left thigh with turbocharged ALT flap elevated. Descending branch of LCFA (main pedicle) with perforators supplying the flap are shown. LCFA, lateral circumflex femoral artery.

Fig. 4

Cross-leg free flap with chimeric latissimus dorsi-serratus anterior flaps anastamosed to the left (uninjured) posterior tibial vessels. The serratus anterior (left) muscle was tubularized around the latissimus dorsi pedicle to provide extra protection before flap division.

Fig. 5

Cross leg free flap inset into right leg defect, providing adequate soft tissue coverage over bone and hardware. The external fixator device holds the two limbs in place to prevent stretch or torque to the pedicle before flap division.

Fig. 6

The flap was divided and fully inset 4 weeks (28 days) after inset. This photograph was taken after flap division, showing adequate perfusion and vascularization of the chimeric flaps. The skin graft also had good take over the muscle flaps.

Fig. 7

Algorithm for reconstruction of Gustilo IIIB and IIIC lower extremity traumatic injuries.