Angiosome (from the Greek angeion, meaning vessel, and somite, meaning segment of the body derived from soma, body). A three-dimensional composite unit of tissue supplied by a given source artery. 

1. The Angiosome Theory
By
Ahmed El-Sayed Sharaf
Assistant Lecturer of Plastic Surgery
Assiut University

2. Contents
• Definition
•Skin Microcirculation
• Studies of Skin Vascular Anatomy
• Angiosome Theory & Concepts
•Implications
• What Beyond The Angiosome

3. Definition
• Angiosome (from the Greek angeion, meaning vessel, and
somite, meaning segment of the body derived from soma,
body).
• A three-dimensional composite unit of tissue supplied by a
given source artery.

4. Skin Microcirculation
The skin has a rich blood supply, far greater than its metabolic demand
because of its role in thermoregulation and immunological function.
• Subepidermal plexus
• Dermal plexus
• Subdermal plexus
• Subcutaneous plexus
• Prefascial plexus
• Subfascial plexus

5. Skin Microcirculation

6. Skin Microcirculation
• Venous drainage of the skin and subcutaneous tissue consists of two
systems interconnected by veins without valves (oscillating or
bidirectional).
• Superficial >>> Subdermal plexus of veins
• Deep >>>Venae comitantes

7. William Harvey, 1628
Studies of Skin Vascular Anatomy
• The earliest accurate description of the
vascular supply to the skin.
• An Anatomical Disputation Concerning the
Movement of the Heart and Blood in Living
Creatures.

8. Wladimir Tomsa, 1873
Studies of Skin Vascular Anatomy
Completed injection studies to describe the
subdermal and dermal plexuses of vessels in the
skin.
Werner Spalteholz, 1893
Performed injection studies to define direct
and indirect perforators to the skin.

9. Carl Manchot, 1880
Studies of Skin Vascular Anatomy
• First detailed description of the human
cutaneous blood supply.
• Identified 40 distinct skin territories, each
receiving its blood supply from a source
vessel.

10. Michel Salmon, 1930
Studies of Skin Vascular Anatomy
• Reappraised Manchot’s work &
produced more detailed description
of approximately twice the number of
vascular territories

11. Behan & Wilson, 1975
Studies of Skin Vascular Anatomy
First to define Angiosome as “the area of skin hat can be cut as a flap which is
supplied by an axial vessel but may be extended by its communication with
branches of an adjacent vessel”.
Cormack & Lamberty, 1986
Expanded the concept of angiotomes by
adding the terms anatomical, dynamic, and
potential to describe the various types of
vascular territories that could be included in
a skin flap based on a single vessel.

12. Taylor & Palmer, 1987
Angiosome Theory
• Taylor and Palmer combined the descriptions of
vascular territories to conceive the three-
dimensional angiosome concept.
• Divided the body into 40 angiosomes based on
named source arteries.
• The named source arteries tend to be quite
consistent in course, size, and branches.

13. Angiosome Theory
• Each source artery & its accompanying
veins supply a composite blocks of skin,
bone, muscle, and other soft tissues.
• Each angiosome is linked to its neighbor
at either by a true (simple) anastomotic
arterial connection without change in
caliber of the vessel or by a reduced-
caliber choke anastomosis.

14. I. Vessels follow the connective tissue
framework of the body
Angiosome Concepts
• Embryologically, vessels develop with connective tissue in the
mesoderm and, through development, remain closely related.
• Major arteries are closely related to the bones of the axial skeleton.
• Their branches at first follow the intermuscular septa. In the deep
tissues, they penetrate the muscles, tendons, bones, nerves, and
deep fat deposits.
• Cutaneous perforators arise from their source artery or one of its
muscle branches and follow the intermuscular or intramuscular
septa toward the surface.

15. II. Arteries radiate from fixed to mobile areas and
veins converge from mobile to fixed areas
Angiosome Concepts
• Areas of fixed skin correspond to the locations at which the deep
fascia is “anchored to bone or to the intermuscular and
intramuscular septa.
• Perforators pierce the deep fascia at areas of fixed skin and then
are oriented from areas of fixed to mobile skin.
• In areas with fixed skin, such as the palms and soles, there will be a
higher density of short perforator branches.
• Areas of mobile skin are supplied by fewer, longer perforator
branches e.g. arm & thigh.

16. III. Vessels “hitchhike” with nerves
Angiosome Concepts
• There is an intimate relationship between
nerves and blood vessels throughout the
deep tissues and the skin and subcutaneous
tissues of the body, especially where a
cutaneous nerve courses on the surface of
the deep fascia.
• Supraorbital, supraclavicular & intercostals.

17. IV. Vessel growth and orientation are products of
tissue growth and differentiation
Angiosome Concepts
• At some stage of fetal development, there are a
fixed number of arteries in the body.
• It explains why vessels radiate from concavities
and converge on convexities and why the vessels
in some areas are small and close together,
whereas in others they are large and spaced well
apart.
• Trapezius “drags” its supplying transverse cervical
artery and nerve across the root of the neck to the
back, together with a large band of skin that it
nourishes.

18. V. Vessels interconnect to form a continuous three-
dimensional network of vascular arcades
Angiosome Concepts
• Throughout the body, each vessel and its
branches are connected with adjacent vessels
and branches of neighboring vessels to form
arches.
• Each vascular territory is surrounded by reduced-
caliber choke anastomotic vessels.
• Venous arcades have a design similar to that of
the arteries but in reverse.
• Examples of arcades are in hands, feet & cubital
fossa.

19. VI. Vessels obey the law of equilibrium
Angiosome Concepts
• The anatomical territories of adjacent
arteries bear an inverse relationship to each
other yet combine to supply the same region.
• If one vessel is small, its partner is large to
compensate, and vice versa.
• This is well illustrated by the relative size of
the superficial epigastric artery and the
perforators of the deep inferior epigastric
artery (DIEA).

20. VII. Vessels have a relatively constant destination but
may have a variable origin
Angiosome Concepts
• This is typical of the vessels that
emanate from the groin to supply the
skin of the lower abdomen and upper
thigh.
• The superficial inferior epigastric and
the superficial circumflex iliac
arteries.
• Whatever the case, their destination
is constant to supply the integument
of the lower abdomen and the hip.

21. VIII. Venous networks consist of linked valvular and avalvular
channels that allow equilibrium of flow and pressure
Angiosome Concepts
• Venous networks consists of segments which have consistent
valves and numerous venous channels, that are free of valves
and allow flow within their lumens in either direction.

22. IX. Muscles are prime movers of venous return
Angiosome Concepts
• Similar to the arterial system, the venae comitantes may drain the integument
directly or indirectly, based on their course either through intermuscular
septa or intramuscular septa, respectively.
• Venae comitantes are efferent veins; they drain the muscles toward the venae
cavae.
• Afferent veins drain blood into nearly all muscles of the body from the
surrounding tissues, which may include the overlying integument, adjacent
muscles, and the bone.
• Muscle contraction is of prime importance for venous blood return, because
this “pumps” the blood back toward the heart.

23.  Skin flap dimensions
Clinical Implications
• Each angiosome defines the safe anatomic boundary of tissue that can be
transferred separately on the underlying source vessels.
• Survival length of a skin flap depends on:
(1) Caliber and length of the dominant vessels flap base.
(2) Caliber and span of the adjacent captured vessels.
(3) Caliber and length of the connecting choke vessels.
(4) Anatomically favorable or unfavorable venous return.
• Where the arterial perforators are large and widely separated, the territory of
flap is large, and a long flap can be raised with safety e.g. scalp & torso

24.  Axes of skin flaps
Clinical Implications
• Knowing the cutaneous arteries of the skin have
provided the basis of “axial” flaps & facilitates
the logical planning of the base and axis of a
skin flap.

25.  Level of Flap Dissection
Clinical Implications
• The deep fascia should be included in the
design of the fasciocutaneous flap in those sites
where the skin is relatively fixed to the deep
fascia e.g., limbs or the scalp.
• Where the skin and subcutaneous tissues are
mobile over the deep fascia, for example, in the
iliac fossae or the breast, it is unnecessary to
include this fascial layer.

26.  The delay phenomenon
Clinical Implications
• The delay phenomenon is based on the physiologic events that
follow a partial restriction in blood flow to tissue either by
partially elevating the flap or its blood supply partially ligated.
• As a result, the choke vessels of the first junctional zone
irreversibly dilate, their caliber increase so that they become
more like true anastomoses. The maximal dilation is seen by 48
to 72 hours after the delay
• It is the only documented technique that can extend the zone of
perfusion to a second or third cutaneous vascular territory.

27.  Composite flaps
Clinical Implications
• A knowledge of the vascular supply of all the
tissues that constitute each angiosome provides
the basis for the transfer of composite units of
skin, muscle, nerve, tendon, and bone supplied
by a single arteriovenous system.
• The vessels within the angiosome interconnect
between the various layers.

28.  Neurovascular Flaps
Clinical Implications
• This neurovascular relationship is
the basis for the design of long
flaps with possibility of providing
sensation at the repair site.
• Also, the possibility of raising
vascularized nerve grafts.

29. What beyond Angiosome ?
• Perforator defined by Salmon as any vessel that
perforates deep fascia to supply overlying subcutaneous
tissue and skin.
• Saint-Cyr, 2009 demonstrated that each
perforator has its own vascular territory, called a
perforasome, which carries a multidirectional
flow pattern that is highly variable and complex.
• These perforasomes are linked to one another
by both direct and indirect linking vessels, which
themselves are linked by communicating
branches.
 Perforasome

30. What beyond Angiosome ?
• Pedicled perforator flap
• Propeller Flap
• Free perforator Flap
 Perforasome

31. What beyond Angiosome ?
• Adhish Basu, 2015
• Each tissue unit, whether skin, muscle, or nerve, has an axial
vasculature that needs to be identified. Once identified, any feeding
vessel supplying this axis should be able to nourish the tissue unit
that may encompass one or adjacent angiosomes.
 Vsculosome

32. Thank You