Christopher R. Geddes

The vascular basis of the thoracodorsal artery perforator flap.

Background: Musculocutaneous perforator flaps, or more simply, perforator flaps, have become increasingly popular in microsurgery because of numerous advantages, including reduced donor-site morbidity. The thoracodorsal artery perforator flap is a cutaneous flap based on cutaneous perforators of the thoracodorsal vessels. The objective of this study was to document the vascular anatomy of this flap in human cadaveric studies. Methods: The anatomy of the perforators of the thoracodorsal artery was studied using a modified lead oxide–gelatin injection technique in 15 fresh human cadavers. Each fresh cadaver was injected with lead oxide, gelatin, and water, and then cooled to 4°C for 24 hours before dissection. The torso was dissected to identify all cutaneous perforators in the region of the back and flank. Results: The mean area of the primary and secondary zones supplied by the thoracodorsal artery was 255 cm2 and 345 cm2, respectively. The mean length of the major and minor axes was 18 cm and 13 cm, respectively. The maximum dimensions of the skin that could potentially be supplied by the thoracodorsal artery averaged 600 cm2, with a major axis length of 28 cm and a minor axis length of 27 cm. A mean number of 5.5 perforators with a mean diameter of 0.9 mm (range, 0.5 to 1.5 mm) supplied this zone. The ratio of musculocutaneous to septocutaneous perforators from the thoracodorsal artery was 3:2. The length of the thoracodorsal pedicle when harvested along with the perforator was 14.0 cm, with the vessel diameter being 2.8 mm at the origin. The most proximal perforator was seen at the level of the inferior angle of the scapula, 3.0 cm medial to the anterior border of the muscle. The intramuscular course of the perforators averaged 5 cm (range, 3 to 7 cm). Septocutaneous perforators from the thoracodorsal artery supplying the skin in addition to the musculocutaneous perforators were seen in 60 percent of specimens. Conclusions: The thoracodorsal artery perforator flap is a reliable cutaneous perforator flap that is very useful in a wide variety of clinical applications.

The Posterior Thigh Perforator Flap or Profunda Femoris Artery Perforator Flap

Background: The thigh donor site has been used extensively for microsurgical tissue transfer; however, the posterior thigh has been neglected as a potential donor site. The perforators of the profunda femoris artery supply large cutaneous territories that could be useful for lower extremity coverage. The purpose of this article is to evaluate the anatomical basis of the posterior thigh perforator flap and to provide anatomical landmarks with which to facilitate flap dissection. Methods: Six fresh cadavers underwent a whole-body, intraarterial injection of a lead oxide and gelatin preparation. The integument of the posterior thigh was dissected (n = 11), and perforators of the profunda femoris artery were identified. Their type (septocutaneous versus musculocutaneous), course, size, and location were documented by angiography and photography. Surface areas were measured with Scion Image Beta 4.02. Results are reported as mean ± SD. Results: The average number of profunda femoris cutaneous perforators in the posterior thigh was 5 ± 2 (65 percent septocutaneous and 35 percent musculocutaneous), the average internal diameter was 0.8 ± 0.3 mm, and the pedicle length was 29 ± 14 mm from the deep fascia and 68 ± 33 mm from the profunda femoris artery. The average profunda femoris cutaneous vascular territory was 229 ± 72 cm2, with a 46 ± 13-cm2 perforator zone. Cutaneous perforators can be found on a line extending from the ischium to the lateral femoral condyle. Conclusions: The profunda femoris provides cutaneous perforators of large caliber supporting a substantial cutaneous territory. This flap will likely be clinically useful in lower extremity reconstruction as a free or pedicled flap.

The Vascular Basis of Perforator Flaps Based on the Source Arteries of the Lateral Lumbar Region

Background: Perforator flaps based on the integument of the trunk have been well described in the literature; however, the anatomy of many donor sites has yet to be adequately documented. The integument of the lateral lumbar region of the trunk is supplied by a number of source arteries (lower posterior intercostal, lumbar, superior epigastric, deep inferior epigastric, superficial inferior epigastric, superficial circumflex iliac, deep circumflex iliac) whose large perforators may be suitable for perforator flap harvest. The purpose of the current study was to describe the vascular anatomy of these perforators in the lateral lumbar region. Methods: A series of five fresh human cadavers were studied using a lead oxide–gelatin injection technique. The integument of the trunk (10 sides or hemitrunk specimens) was dissected, and the perforating vessels (diameter ≥0.5 mm) were identified, noting vascular origin, diameter, and pedicle length. Radiographs of tissue specimens were digitally analyzed using the software Scion Image for Windows (Scion Corp., Frederick, Md.) to determine vascular territories. Results: The source vessels contributed a summed mean of 33 perforators per hemitrunk, with a mean emerging vessel diameter of 0.7 ± 0.2 mm and a corre- sponding mean superficial pedicle length of 31 ± 24 mm. The total area of skin supplied directly by these 33 perforators was 1200 cm2, equating to a mean area of 37 cm2 per perforator. Conclusion: The authors have comprehensively described the anatomy of perforators of the lateral lumbar region of the trunk.

Reversed forearm island flap supplied by the septocutaneous perforator of the radial artery: anatomical basis and clinical applications.

The cutaneous perforators of the radial artery adjacent to the superficial branch of the radial nerve and the lateral antebrachial cutaneous nerve were investigated, and the vascular anatomical features of the reversed forearm island flap supplied by those accompanying perforators were documented. Ten fresh cadavers were systemically injected with lead oxide, gelatin, and water. Twenty forearms were then dissected, and an overall map of the cutaneous vasculature and source vessels was constructed. The accompanying arteries were observed to lie along the lateral antebrachial cutaneous nerve and the superficial branch of the radial nerve and to nourish the skin through cutaneous branches. Vascular communication among these cutaneous vessels was evaluated, to determine the cutaneous vascular territory of the radial forearm flap. This anatomical information facilitates flap design in the forearm region. Clinical experience regarding the usefulness of the reversed forearm island flap for hand reconstruction for a series of five patients is presented.

Digital Vascular Mapping of the Integument About the Achilles Tendon

BACKGROUND Soft-tissue coverage and vascularity likely play a vital role in the genesis of wound complications and infections during open Achilles tendon repair. Planning an appropriate surgical approach might decrease the prevalence of these complications. METHODS Five adult cadavers underwent whole-body arterial perfusion with a mixture of lead oxide, gelatin, and water. The skin of the foot and ankle was dissected, and the vascular supply was evaluated with angiography. All angiograms were analyzed with use of statistical software. RESULTS We constantly identified three vascular zones: (1) the medial vascular zone, which had the richest blood supply; (2) the lateral vascular zone, in which the density of vascularity was good and much better than that in the posterior zone; and (3) the posterior vascular zone, which showed the poorest blood supply. CONCLUSIONS The richest vascular zones of the skin covering the Achilles tendon are located toward the medial and lateral aspects of the Achilles tendon. On the basis of the present study, we recommend using a medial or lateral incision in the integument covering the tendon, as the posterior incision will be located in a less vascular zone. CLINICAL RELEVANCE The present study should help the surgeon to plan the surgical approach to the Achilles tendon by designing skin incisions in a more vascular zone.

An assessment of the anatomical basis of the thoracoacromial artery perforator flap

BACKGROUND Musculocutaneous perforator flaps offer advantages over musculocutaneous flaps, including reduced donor site morbidity, more predictable reconstruction of soft tissue deformities, and a wider variety of flap options. Perforator flaps are becoming increasingly popular for many applications. In the present study, we set out to examine the various perforators of the thoracoacromial axis through the pectoralis major (PM) muscle with respect to their suitability for transfer to the head and neck region as a pedicled flap. METHODS A series of 10 fresh cadavers were injected with lead oxide, gelatin and water (250 mL/kg) through the femoral vessels. The cadavers were cooled and the integument was removed. Perforating vessels from the underlying muscles were marked and the resulting angiograms of the integument and deep tissues were compared with the dissection notes describing the course, size and distribution of the perforating vessels. RESULTS THE PERFORATORS THROUGH THE PM MUSCLE TO THE OVERLYING SKIN INCLUDED THREE REGIONAL GROUPS: perforators of the thoracoacromial axis; perforators of the medial intercostal vessels; and perforators of the lateral thoracic artery. The major group of perforators supplying the overlying skin was from the intercostal vessels. However, the thoracoacromial axis did consistently give rise to perforators in the upper portion of the PM muscle. In particular, there were reliable perforators from the clavicular and deltoid branches of the thoracoacromial artery. DISCUSSION The present study illustrates the potential clinical applications of a series of perforator flaps based on the thoracoacromial axis, which may be useful in head and neck reconstructive surgery.

Neurovascular territories of the external and internal oblique muscles

The purpose of this study was to document the extent of the arteries supplying the external and internal oblique muscles and the connections among the vascular territories. Ten adult human cadavers underwent whole-body arterial perfusion (200 ml/kg) with a mixture of lead oxide, gelatin, and water, through the carotid artery. The external and internal oblique muscles were dissected and subjected to radiography. The vasculature of each muscle was analyzed by using the paper template technique. The areas of the vascular territories of the individual intercostal arteries within the external oblique muscle varied from 9 to 22 percent. The area of the vascular territory of the muscular branch of the deep circumflex iliac artery was 5 to 18 percent. The ascending branch of the deep circumflex iliac artery supplied a mean of 35.7 percent of the vascular territory of the internal oblique muscle. The lower six posterior intercostal arteries supplied a mean of 48.5 percent. The lateral branches of the deep inferior epigastric artery supplied a mean of 15.8 percent. This information provides the basis for the design of external and internal oblique muscle flaps for functional muscle transfer.

Vascular basis of intrinsic muscle flaps in the hand.

Background: Intrinsic hand muscles can occasionally be used as pedicled flaps for wound coverage or functioning transfer in hand trauma. The purpose of this study was to define the vascular supply of the individual intrinsic muscles of the hand for potential use of these muscles as muscle flaps. Methods: In part A, 10 fresh cadavers were injected using a lead oxide–gelatin injection technique. The intrinsic muscles were meticulously dissected, removed, and radiographed. The number, type, and diameter of the vascular pedicles of each muscle and their distribution within the muscle were analyzed. The area of the vascular territory supplied by each source vessel was calculated. In part B, 10 embalmed cadavers were injected with red latex and a similar dissection protocol was followed. Results: The 18 hand muscles each received an average of 3 ± 1 vascular pedicles. The average diameter was 0.8 ± 0.2 mm; the length and width of the area supplied by each pedicle was 2.2 ± 0.4 cm and 1.0 ± 0.2 cm, respectively. The vascular territories of the majority of hand muscles were aligned longitudinally along their long axes. Nine intrinsic hand muscles have been identified that can potentially be used as a muscle flap or musculocutaneous or musculo-osseous flap. Conclusions: The size and course of the vascular pedicles to the hand muscles are variable. This anatomical study provides an improved understanding of the vascular supply of the intrinsic muscles of the hand and provides further information to assist in the design of intrinsic hand muscle transfer.