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Page 4 of 10 Schaeffer et al. Plast Aesthet Res 2022;9:27 https://dx.doi.org/10.20517/2347-9264.2021.122

allograft provides immediate strength to the construct, while the fibula graft provides the previously noted
biologic benefits of vascularized bone graft (potential for osteogenesis, ability to hypertrophy, and faster
[12]
time to the union) .

Vascularized iliac crest bone grafts have been described for lower extremity bone reconstruction. This
corticocancellous bone has a slight curve, which is undesirable in long bone reconstruction. This maximal
graft length from this donor site is only 10 to 12 cm. The flap pedicle is the deep circumflex iliac vessel. An
associated skin paddle based on the deep circumflex iliac vessels alone is reportedly unreliable - if a large
skin paddle is required for osteocutaneous reconstruction, a double anastomosis including the superficial
circumflex iliac vessels should be performed [14,18-20] .

The medial femoral condyle (MFC) flap has been popularized for use in the setting of post-traumatic
avascular necrosis of the talus and navicular bones and the setting of foot and ankle fracture nonunions. The
MFC is typically a thin corticoperiosteal graft that includes periosteum and outer cortical bone, with or
without underlying cancellous bone. The dominant flap pedicle is the descending genicular artery; however,
the flap can be supported by the medial superior geniculate artery (though this results in a shorter pedicle
length). The advantage of this flap is its thin, pliable nature which allows for shaping to fit small, irregular
bone defects . When used for structural support, the maximal graft length is 3 cm in length; however, flaps
[9]
up to 5 cm × 7 cm have been described [21,22] . The MFC can be raised with an associated skin paddle based on
the saphenous artery branch of the descending geniculate artery pedicle (medial knee, up to 70 cm ) or a
2
more distal descending geniculate artery cutaneous perforator (medial distal thigh and proximal leg, up to
2 [23,24]
361 cm ) . Because of variable branching patterns and available distal cutaneous perforators, the size of
the skin paddle associated with an MFC flap is inconsistent [24,25] .

PRE-OPERATIVE CONSIDERATIONS
In the post-traumatic setting, multiple operative debridements are often required to adequately address
contamination and removal of devitalized bone and soft tissues with the goal of eradicating potential nidi
for infection. Provisional bony stabilization is typically obtained with external fixation. In the setting of
associated soft tissue loss (Gustillo IIIB or IIIC), some authors recommend single-stage reconstruction with
composite bone grafting, while others advocate for soft tissue reconstruction followed by vascularized bone
grafting in a second stage 6-8 weeks later. The advantages of one-stage reconstruction include reduction of
overall healing time and simultaneous soft tissue and bone reconstruction, with the theoretical disadvantage
of increased risk of infection and loss of the vascularized bone graft. The disadvantages associated with
staged reconstruction include increased scar burden and limited availability of recipient vessels for
subsequent vascularized bone grafting [26-31] . The optimal timing for soft tissue reconstruction and
vascularized bone grafting should be determined on a case-by-case basis, keeping in mind the limitations of
each approach.

Evaluation of the donor and recipient vascular anatomy in the setting of lower extremity trauma is an
important component of the pre-operative workup. This includes clinical evaluation and Doppler
ultrasound examination. Angiography of the recipient and/or donor sites can be performed if there are
abnormalities on exam and for pre-operative planning. In the setting of high-energy trauma, the extent of
injury to the potential recipient vessels can be assessed with angiography [18,20] . However, pre-operative
angiography may not reliably delineate the extent of vascular injury in the recipient vessels following trauma
or in patients with chronic infections. Vein grafts may be required based on the availability of healthy
[13]
recipient vessels outside of the zone of injury .