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Mayland et al. Plast Aesthet Res 2021;8:62 https://dx.doi.org/10.20517/2347-9264.2021.38 Page 5 of 10

diameter of the radius bone cannot be harvested, limiting it to a single cortex following the harvest of 40%-
60% of the radius circumference. Subsequently, there is insufficient bone stock to support dental
implantation and necessitates prophylactic plating the radius to prevent fracture [31,32] . In addition, the
fasciocutaneous tissue volume available is often less than the soft tissue available with the fibula.

Fasciocutaneous and myocutaneous only donor sites
In patients who do not require a vascularized segment of bone, a radial forearm or anterolateral thigh flap
may be utilized. These flaps are applicable in ORN of the anterior skull base or lateral temporal bone for soft
[33]
tissue coverage . The radial forearm free flap is a fasciocutaneous flap that is thin and pliable, with reliable
pedicle length and high rates of flap survival. However, this flap contains limited subcutaneous adipose in
the majority of patients and lacks a muscle component making it inadequate for defects with large volume
loss. Conversely, the anterolateral thigh free flap (ALT) may be composed of a combination of skin, adipose,
fascia, or muscle. Adipose allows for improved volume retention as it is less subject to atrophy and
contracture over time. However, depending on the thickness of the ALT subcutaneous adipose, it may
provide more bulk than desired.

OPERATIVE CONSIDERATIONS
When reconstructing with an osseous donor site, consideration of bone segment length is important. For
the periosteum to provide sufficient blood study, it is recommended that each bone segment measure at
least 2 cm in length. The ability to create multiple osteotomies can improve facial contouring. However, it
also reduces the length of the pedicle. This can create additional challenges in vessel depleted, radiated necks
where contralateral vessels or vessels in the base of the neck (transverse cervical, dorsal scapular, or internal
mammary) may necessitate a longer pedicle length.

VIRTUAL SURGICAL PLANNING
Virtual surgical planning (VSP) can be utilized to aid in flap design preoperatively. VSP allows for the
creation of patient-specific cutting guides and plates, which may increase free flap accuracy and reduce
operative times [34,35] . The use of VSP is thought to improve bone-to-bone contact, reducing rates of
malunion or nonunion and the subsequent sequalae [36,37] . The VSP software also provides information
regarding the thickness of bone to aid in selecting sites for screw placement, ensuring adequate bone
thickness, and reducing screw mobility and subsequent hardware extrusion [36-38] . VSP can also be used to
mirror the healthy bone allowing for more symmetric reconstruction that more accurately reflects the
anatomical positioning prior to developing ORN. Additionally, VSP can aid in planning the ideal
orientation of the pedicle .
[39]

TECHNICAL CONSIDERATIONS
Flap geometry and vessel selection can be quite challenging in patients with ORN. Tissue damage and
fibrosis from prior radiation therapy and chronic infection can complicate dissection of recipient
vasculature and impact the vessel wall integrity and caliber. A previous publication found that over half of
[17]
free flap reconstructions for ORN required the use of the contralateral neck vessels . Similarly, we have
found improved free flap survival rates when using contralateral neck vessels .
[40]
Reconstruction bar thickness varies among surgeons, ranging from 1 to 3 mm and averages 2.1 mm. An
example of a 2.0 mm reconstruction bar is shown in Figure 2A. Recent data suggests that reconstruction bar
thickness may correlate with overlying soft tissue loss and hardware exposure rates, with a higher incidence
of complications as reconstruction bar thickness increases .
[40]