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Page 10 of 15 Crowe et al. Plast Aesthet Res 2019;6:4 I http://dx.doi.org/10.20517/2347-9264.2018.70

Figure 3. Dynamic ankle foot orthosis with a pretibial shell that allows for offloading of the foot and ankle

LOWER EXTREMITY RECONSTRUCTION
Goals of reconstruction
The term “lower extremity reconstruction” consists of a heterogenous grouping of procedures that aim
to restore function, bony support, and adjacent soft tissues of a lower extremity defect of deformity. As
previously mentioned, reconstruction of the lower extremity attempts to achieve functional weight bearing
and independent ambulation. Several scoring systems have been created to predict the potential for limb
salvage after traumatic injury [52-57] . These systems, however, are unable to accurately predict which patients
will eventually undergo an amputation because of their low sensitivities, limiting their usefulness in the
[58]
clinical setting . The decision to perform a lower limb reconstruction is therefore determined based on the
specific patient factors and needs, ultimate cost, and social support for rehabilitation.

Orthoses after lower extremity reconstruction
The primary goal of orthosis in this context is to protect the both remaining and reconstructed soft tissue.
One illustrative area of this concept is following reconstruction of the plantar surface of the foot. The heel
pad and distal plantar region are characterized by distinct microarchitectural anatomy that withstand
compressive and shear forces during the gait cycle. Reconstructed soft tissue with skin grafts, locoregional
flaps, and free tissue transfer must also resist these forces. The result of inadequately redistributed pressure
is altered gait mechanics, pain in sensate tissue, and recurrent ulceration [59,60] . The use of total contact insoles
after hindfoot reconstruction has been shown to reduce maximal forces in the heel and improve walking
[61]
speed .

Over the last 10 years, there have been significant advances in offloading ankle/foot orthosis designs
that have allowed people with significant lower extremity trauma to participate in higher-level activities.
Dynamic AFOs are passive devices that control ankle motion and limit weight bearing through the ankle to
address pain, weakness and limitations in range of motion [62-64] . Dynamic AFOs are typically made of carbon
fiber with a pretibial shell that allows for offloading of the foot and ankle with posterior struts of variable
stiffness [Figure 3]. The device stores energy during the stance phase and uses it to generate a more forceful
push-off.