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Page 2 of 10 Schaeffer et al. Plast Aesthet Res 2022;9:27 https://dx.doi.org/10.20517/2347-9264.2021.122

[4]
The first successful free vascularized bone graft was performed and described by Taylor et al. in 1978 for a
post-traumatic intercalary bone defect - a free fibula flap was used to reconstruct a 12.5 cm defect of the
[5]
tibia. Subsequently, the vascularized rib (Buncke et al. , 1977) and vascularized iliac crest (Taylor and
[6]
Watson , 1978) bone grafts were successfully performed and described in the literature for lower extremity
bony reconstruction. The medial femoral condyle flap was first described in 1990 by Hayashi and
[7]
Maruyama, and applied to lower extremity reconstruction by Doi and Sakai in 1994. Since the 1970s, the
vascularized free fibula flap has remained the workhorse flap for post-traumatic lower extremity bony
reconstruction, followed by the less commonly utilized iliac crest, medial femoral condyle and rib donor
sites .
[8,9]

INDICATIONS FOR VASCULARIZED BONE GRAFTS
Several classification systems have been created in attempts to uniformly describe the degree of lower
[10]
extremity trauma. The Gustilo and Anderson classification is well known and categorizes open fractures
based on the degree of soft tissue injury. Unlike the Gustilo system, the extent of bony defects can be
described with Winquist’s classification system. This system was originally created to describe femur
[3]
fractures; however, it has been subsequently applied to tibial shaft fractures [3,11] . Battiston et al. recommend
non-vascularized bone grafting for Winquist grade 1 or 2 fractures (no or minimal comminution and more
than 50% contact between fragments with moderate comminution, respectively). For fractures with less
than 50% contact between fragments, more severe comminution, or segmental bone loss (Winquist grades 3
[3]
and 4), reconstruction with bone transport or vascularized bone grafting is suggested . While several
techniques have been described for bony reconstruction, vascularized bone grafting remains the modality of
choice in the setting of large bony defects (> 6 cm) [12,13] . Additional indications for vascularized bone grafting
include poor vascularity of the recipient site, repeated failure of non-vascularized bone grafts, and fracture
[14]
nonunion .

BIOLOGY
The proposed advantages of vascularized bone grafting for reconstruction of post-traumatic lower extremity
bone defects include a sturdier immediate reconstruction and the capacity for osteogenesis, which
ultimately allow for faster incorporation and primary bone union times [3,12] . Unlike avascular bone grafts,
the process of creeping substitution is bypassed. Therefore, vascularized bone grafts have less resorption
with better retention of bony architecture, resistance to infection, mechanical strength, and healing
potential [15,16] . Additionally, vascularized bone grafts are capable of responding to applied biomechanical
stresses with hypertrophy .
[17]

GRAFT TYPES
The three primary donor site options for vascularized bone grafting for the lower extremity include the
fibula, iliac crest, and medial femoral condyle [Figure 1]. Historically, vascularized rib grafts have been
described; however, they have fallen out of favor. Flap selection is determined predominantly based upon
the size and location of the bony defect, flap availability, donor site morbidity, and flap success rates.
General considerations when selecting the ideal vascularized bone graft for a post-traumatic bone defect in
the lower extremity are outlined in Figure 2.

The fibula flap is the most commonly used vascularized bone graft for extremity reconstruction. It provides
a strong cortical strut that is straight, and therefore ideal for extremity reconstruction. The vascularized
fibula flap can be used to reconstruct defects up to 26 cm in length . The flap pedicle is the peroneal artery
[18]
with associated peroneal veins. The composition of this flap can vary to include skin, fascia and muscle as
indicated by the defect requirements. A skin paddle up to 20 by 10 cm can be reliably transferred and used