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Seu et al. Femoral head reconstruction in pediatric patient

CASE REPORT

An otherwise healthy 8-year-old girl initially presented
with left hip pain and was treated for presumed
osteomyelitis; however, upon open biopsy of the left
femoral neck, she was found to have ES extending
from the femoral neck into the proximal diaphysis. The
patient began a neoadjuvant chemotherapy regimen
as specified by her local hospital protocol. Past
medical history and family history are unremarkable.

Eight months after initial onset of symptoms, the
patient and her family met with her treatment team at
Johns Hopkins, which included pediatric orthopedic
oncology and plastic and reconstructive surgery
[Figure 1]. She and her family decided to pursue
single staged resection of the primary tumor and
reconstruction of the left proximal femur using an
Figure 1: Magnetic resonance imaging of primary Ewing sarcoma
tumor in patient’s left hip ipsilateral vascularized fibula autograft and cadaveric
femoral allograft shell with articular restoration through
preservation of the native femoral head.
prostheses and non-vascularized allografts are
insufficient for pediatric patients due to the need The patient was taken to the operating room and
to both restore joint function and preserve growth placed on her right side. The left proximal femur was
potential . Vascularized fibular head autografts have accessed via a lateral approach, starting proximal
[5]
been previously used successfully in mandibular to the joint and extending distally approximately
[6]
and radial reconstructions . The proximal femur halfway down the thigh. The muscular attachments
and acetabulofemoral joint has a unique structure were dissected off the femur and the tumor was
that allows wide range of motion and weight-bearing excised en bloc, revealing negative margins. An
properties. Reconstruction using a vascularized fibular anterior capsulectomy was performed. The femur was
autograft alone is insufficient to restore the native dislocated from the acetabulum and a circumferential
anatomy of the proximal femur. However, its structure capsulotomy was performed in order to save the
can be augmented using an acellular cadaveric femoral head cap and preserve the native articular
femoral allograft, which acts as a scaffold on which the anatomy. After tumor excision, the defect extended
[6]
autograft can grow . Utilizing this method preserves from immediately below the femoral head cap to the
the epiphyseal plate in a child, restoring both function proximal portion of the diaphysis.
and growth potential. Previous studies have combined
acellular allografts with vascularized fibular autografts The fibular harvest was initiated with a lateral incision
to reconstruct intercalary bony defects post-tumor on the ipsilateral leg. The musculature was elevated
resection [7-10] . However, there is a paucity of research off the fibula and the anterior crural septum was
on the reconstruction involving epiphyseal portions of transected. A distal osteotomy was performed 6 cm
[6]
long bones and articulations with this method . below the lateral malleolus using an oscillating saw.
The deep peroneal artery and vein were ligated
We present a case of an 8-year-old female with ES of distally to be used as the vascular pedicle. The fibula
the left proximal femur who underwent wide resection and vascular pedicle were elevated completely out of
of the primary tumor followed by reconstruction of the the leg.
acetabulofemoral joint using a vascularized fibular
head free flap with a cadaveric femoral head allograft Within the left hip, the descending branch of the lateral
shell. The patient had no complications at 6-month femoral circumflex artery and vein were dissected out
follow-up. This case report demonstrates the novel to their origin, prepared by microscope, and clamped.
use of an acellular cadaveric femoral allograft with a Meanwhile, the cadaveric femoral allograft shell was
free fibula autograft including the articular head of the prepared ex-vivo by cutting the allograft length-wise
fibula for complex proximal femoral reconstruction of and reaming out the core to create a trough for the
the femur and hip joint. fibular autograft. The fibular autograft was fractured to

210 Plastic and Aesthetic Research ¦ Volume 4 ¦ November 30, 2017