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Page 2 of 12 Wee et al. Plast Aesthet Res 2019;6:12 I http://dx.doi.org/10.20517/2347-9264.2019.02

Keywords: Vascularized bone, vascularized bone grafts, composite extremity defect restoration, bone reconstruction,
free tissue transfer, microsurgery

INTRODUCTION
Segmental long bone defects and bony nonunions can arise after traumatic injury, oncologic resection, or
osteomyelitis. Establishing a stable bony framework is critical to successful limb salvage; however, bony
reconstruction often presents complex challenges to the reconstructive surgeon with seemingly limited
available options. One must consider a variety of factors when selecting the appropriate treatment modality
from a multitude of limb salvage options. Among these considerations are the surgeon’s training background
and experience, location and size of defect, associated injuries, availability of soft tissue coverage, and patient
comorbidities.

Research and technology have led to a surge of products for bony reconstruction that obviate the
need for autologous bone harvest, avoiding the potential donor site morbidity. These include both
allografts and synthetic products such as bone morphogenic protein (Medtronic, Minneapolis, MN),
polymethylmethacrylate (Zimmer Biomet, Warsaw, IN) and tricalcium phosphate (Depuy Synthes, New
Brunswick, NJ). Many of these technologies possess osteoconductive and/or osteoinductive properties, or
can be combined with another product to achieve both. Clinical studies suggest that both allograft and
autograft can lead to adequate healing in a well-vascularized wound bed, with the end points being time to
incorporation and lack of wound healing complications such as nonunion .
[1]
However, these products are subject to their own set of limitations and disadvantages, including the risk
of disease transmission, infection and autoimmune rejection. More importantly, the Diamond Model of
fracture healing describes 4 requirements for adequate fracture healing which are best met by autologous
reconstruction: osteogenic cell supply, an osteoconductive scaffold, growth factors, and a stabilized
environment . In particular, the lack of osteogenic cell supply in allograft and synthetic materials may
[2]
be the reason they have demonstrated inferior outcomes in critically sized defects > 1 cm, or in those of
increasing severity .
[3]

Thus, autogenous bony reconstruction remains the gold standard for bone loss. As there are many options
to consider in this category, an initial size-based elimination approach can be helpful. Intramedullary nail,
external fixation, and internal fixation techniques are options when there is no bone gap. When there is
a bone gap, more complex procedures are appropriate depending on the size of the gap; these are further
illustrated in Table 1.

While it serves as a good starting point, bone gap size is only one of many factors contributing to decision-
making in orthopaedic and orthoplastic reconstructions. In the senior authors’ practices, the utility and
versatility of vascularized bone grafts (VBGs) for challenging bony reconstruction has expanded limb
salvage options for many patients treated at our medical centers. The following cases demonstrate how fibula
VBGs can optimize restoration of large segmental bone defects and resolution of nonunion cases to achieve
definitive bony healing.

MATERIALS/METHODS
This is a retrospective case series of VBGs performed by a single surgeon over a seven-year period. Twenty-
seven (27) total VBGs met inclusion criteria and underwent reconstruction for traumatic (16), oncologic (6)
and chronic degenerative (5) etiologies. Patient age ranged from 5 to 64 years with the majority of patients
being younger than 30 years old. Anatomical bony reconstructions included 13 upper vs. 11 lower extremity