AAHS ASPN ASRM - 2013 Annual Meeting - American Association ...

Anatomy and Hystology of the Latissimus Dorsi Subunits for Facial Reanimation
Institution where the work was prepared: Souza Aguiar City Hospital and Federal University of São Paulo, Rio de Janeiro and São Paulo, Brazil
André Salo Buslik Hazan, MD1; Fábio Xerfan Nahas, PhD, MD2; Marcus Vinícius Jardini Barbosa, PhD, MD2; Eugênio Piñeda, PhD, MD3; Lydia Masako Ferreira, PhD, MD2;
(1)Souza Aguiar City Hospital of Rio de janeiro and Federal University of São Paulo, (2)Federal University of São Paulo, (3)Souza Aguiar City Hospital
BACKGROUND:
The use of muscular flaps for the correction of defects after mimetic muscles damage has been described. However, these flaps showed restrictions because of
the large volume of muscle transferred and the vector in a single direction. Recently, perforator flaps has been widely used but its limitation is offer only cutaneous
cover. The goal of this type of reconstruction is to restore both muscular and cutaneous cover with tissues that presents similar size and thickness of
the damage multiple mimetic muscles of the face with different force vectors. The purpose of this study is to present the anatomy and histology of the latissimus
dorsi subunits for facial transplantation and to present a case report with this alternative reconstruction technique.
METHODS:
Ten fresh adult cadavers were dissected. The latissimus dorsi muscle was dissected and the perforators vessels are identified. The vessel that supplies the overlying
skin is individualized. Dissection proceeds into the muscle, sectioning the epimysium and the perimysium, individualizing the lateral segmental bundle or the inferior
one. Then, the vascular and nervous subsegmental bundles penetrating the corresponding muscular groups are observed. The neurovascular subsegmental bundles
and the muscular subunits are isolated by dissection. Each subunit was isolated and was histologically evaluated. A histological search for an artery, a vein and
a nerve was performed 3 mm before and right at the penetration of the pedicle within the muscle. The external diameters of these structures were measured.
RESULTS:
Subunits of independent muscles were created. They are supplied by a subsegmental vessels pedicle connected to a lateral or inferior segmental vessel, which is a
branch of the thoracodorsal vessel. Histological study showed that ninety eight percent of the subunits presented at least one artery, one vein and one nerve.
CONCLUSION:
This study supports the use of subunits of latissimus dorsi flap as a substitute of mimic facial muscles.
The Free Partial Superior Latissimus (PSL) Muscle Flap: Preservation of Donor Site Form and Function
Institution where the work was prepared: The Buncke Clinic, San Francisco, CA, USA
Karen M. Horton, MD, MSc, FRCSC; Rudolf F. Buntic, MD; Darrell Brooks; Charles K. Lee; The Buncke Clinic
PURPOSE:
The latissimus dorsi flap is widely applied, reliable and versatile for microvascular reconstruction. Harvest of the entire muscle results in sacrifice of form, creates a
large donor space, and may create functional loss. Use of the superior portion only decreases donor site morbidity and provides a flap of variable size. We describe
the partial superior latissimus (PSL) muscle flap, its harvest technique, and application as a microvascular transplant for complex defects in thirteen patients.
METHODS:
The superior portion of the latissimus dorsi is isolated on the transverse branch of the thoracodorsal artery though a transverse incision parallel to the upper
muscle border. The pedicle is followed proximally as needed for sufficient length. For functional PSL muscle transfer, the transverse branch of the thoracodorsal
nerve is dissected intraneurally, leaving the branch to the lateral latissimus intact.
RESULTS:
Thirteen patients have undergone PSL flap procedures: 11 were used for extremity salvage or complex wounds, 2 were transplanted for facial reanimation and one sensory
innervated flap was used to achieve a sensate heel. Flap dimensions ranged from 10 x 5 cm to 24 x 12 cm. All flaps survived; one hematoma occurred in a patient
on perioperative heparin. A symmetrical lateral thoracic silhouette was maintained and the remaining latissimus muscle functioned postoperatively in all patients.
DISCUSSION:
Harvest of the superior portion of the latissimus muscle on the transverse branch (TB) of the thoracodorsal vessels (TDA) preserves the entire lateral and inferior
elements of the muscle via the descending branch (DB), together with its nerve supply. This preserves the lateral thoracic form and decreases potential
functional muscle loss. Similar to the partial medial rectus flap, a reliable muscle flap of variable size can be designed while preserving donor site form and
function. “Muscle-sparing” latissimus flaps have been described; however, lateral muscle dissection or complete muscle harvest were used. Innervation of the
PSL flap and neurrorhaphy to a recipient motor nerve enables functional muscle transplantation.
CONCLUSIONS:
The PSL flap has the following advantages: (1) variable flap size, (2) large caliber vessels, (3) a potentially long vascular pedicle, (4) preservation of the majority
of the latissimus muscle in situ, (5) maintenance of the dorsal thoracic silhouette, (6) potential for neurotization and sensory/functional muscle reconstruction
and (7) use as a myocutaneous flap by including the overlying skin territory. Thirteen cases have been successfully completed for a variety of anatomic
defects and reconstructive purposes.
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