Anatomy of the leg and the keys of Anatomical considerations in Reconstructive surgery

1. Anatomy of the Leg
Dr:Mohamed Amin
Plastic Surgery Department-Shebin Elkom Teaching
Hospital
Zgl.mohamedamin@gmail.com

2. Anatomy of the leg includes:
1-Skin and subcutaneous tissue
2-Fascia
3-Bones
4-Muscles
5-Nerves(motor,sensory)
6-Arterial Supply
7-Venous Drainage
8-Lymphatic Drainage
9-Keys of Leg anatomy in Reconstructive surgery

3. 1-Skin
 The skin consists of two layers: a stratified
squamous epithelium called the epidermis and a
deeper connective tissue layer called the dermis

4. Layers of the Epidermis:
 1. The stratum basale consists mainly of a single layer of
cuboidal to low columnar stem cells and keratinocytes resting on
the basement membrane.
 2. The stratum spinosum consists of several layers of
keratinocytes; in most places, this is the thickest stratum, but on
the palms and soles it is usually exceeded by the stratum
corneum.
 3. The stratum granulosum consists of three to five layers of flat
keratinocytes—more in thick skin than in thin skin—and some
dendritic cells.
 4. The stratum lucidum is a thin translucent zone seen only in
thick skin.
 5. The stratum corneum consists of up to 30 layers of dead,scaly,

5. Layers of skin

6. The Dermis
 It is composed mainly of collagen,elastic and reticular fibers,
fibroblasts, and the other cells. It is well supplied with blood
vessels, cutaneous glands, and nerve endings.The hair follicles and
nail roots are embedded in the dermis.
 There are two zones of dermis called the papillary and reticular
layers
 papillary layer is a thin zone of areolar tissue, The reticular layer of
the dermis is deeper and much thicker. It consists of dense irregular
connective tissue

7. Fascia
a-Superficial fascia:a layer of loose areolar connective tissue of
variable thickness and fat contents.
b-Deep fascia:is a sheet of connective tissue that separates
neighboring muscles or muscle groups from each other and from the
subcutaneous tissue.The deep fascia of the leg is very strong.it divides
the leg into three fascial compartments each having its own muscles,
arteries, and nerves : anterior, lateral, and posterior. In the posterior
compartment, the muscles are divided into three layers by the
superficial and deep transverse fascial septa

8. Leg compartments and fasciae

9. Leg intermuscular septa

10. Bones:
A-Tibia:
 It provides 85% of the weightbearing capacity of the leg.it articulates with the
femur proximally and joins fibula to articulate with the talus distally.it is
connected to fibula in the midportion with the interosseous membrane.it has
medial,lateral and posterior surfaces.the medial surface is subcutaneous and thus
most prone to exposure during injury.the lateral and posterior surfaces are well
protected by muscles

11. B-fibula
 it is the second bone of the leg.it serves as a structure for
muscle and fascial attachments.becuase it is not
weightbearing and is in a relatively protected position,it is
of less concern in trauma,except when lateral malleolus is
involved

12. Tibia and Fibula

13. Nerve supply in the leg:
A-motor supply:
 Sciatic nerve (largest and thickest nerve in the body) arises from
sacral plexus (L4-S3).
 In the lower part of the back of thigh, sciatic nerve divides into
tibial and common peroneal nerves.

14. Tibial Nerve:
 It is present on the Posterior Compartment of the leg and
supplies all it’s muscles on(gastrocnemius, plantaris,
popliteus and soleus). At the ankle,behind medial
malleolus, it divides into medial and lateral plantar
nerves, which together supply all the muscles of the sole.
 It gives sensory branches to the knee joint and a large
cutaneous branch, which passes into the calf to form the
sural nerve

15. Tibial Nerve(Cross section of leg)

16. Common peroneal nerve
 At the lateral side of the neck of fibula, it divides into the deep and
superficial peroneal nerves. The common peroneal nerve is the
smaller terminal branch of the sciatic nerve. It arises in the lower
third of the thigh just above the popliteal fossa. It passes into the
popliteal fossa along its upper lateral boundary just beneath the
edge of the biceps tendon. Now, it runs over plantaris and the
lateral head of gastrocnemius. It runs over the fibular attachment
of the soleus to wind around the lateral aspect of the neck of fibula
to reach deep to peroneus longus where it divides into two terminal
branches—deep and superficial peroneal nerves limb

17. Deep peroneal nerve
 is present in the anterior compartment of the leg and supplies all the anterior leg
muscles(peroneus tertius,extensor digitorum longus,extensor halluces
longus,tibialis anterior).
 It begins on the lateral side of the neck of fibula
 It enters the anterior compartment of the leg by piercing the anterior
intermuscular septum. It pierces extensor digitorum longus and descends in this
compartment with the anterior tibial artery
 The nerve lies lateral to artery in its upper one-third and lower one-third and
anterior to artery in the middle one-third. It is said that in the middle one-third
the nerve hesitates to cross the artery from lateral to medial side, so it goes back
to the lateral side of the artery.Hence, deep peroneal nerve is also referred to as
nervus hesitans

18.  The nerve ends in front of the ankle by dividing into the lateral and
medial terminal branches.The lateral terminal branch runs laterally
and ends in a pseudoganglion deep to the extensor digitorum
brevis.Branches from the pseudoganglion supply the extensor
digitorum brevis and tarsal and metatarsal joints on the lateral side
of the foot. The medial terminal branch runs forward and ends by
supplying the skin of the adjacent sides of big and second toes (first
interdigital cleft) and the first dorsal interosseous muscle

19. Deep peroneal nerve(cross section of leg)

20. superficial peroneal nerve
 it is present in the lateral compartment of the leg and supplies all
the lateral leg muscles (peroneus longus,peroneus brevis)
 It arises in the substance of peroneus longus on the lateral side of
the neck of fibula
 It begins on the lateral side of the neck of the fibula and descends
for a short distance between the peroneus longus and peroneus
brevis, and then lies in a groove between the peroneus brevis and
extensor digitorum longus. At the junction of the upper two-third
and lower one-third of the leg, it pierces the deep fascia, and soon
divides into a medial and a lateral terminal branches which reach
the dorsum of the foot

21.  It gives cutaneous branches that supply the skin of the lower one
third of the lateral side of the leg and dorsum of the foot, except
for the territories supplied by the saphenous, sural, and deep
peroneal nerves.
 The medial terminal branch of the superficial peroneal nerve
crosses the ankle and divides into two dorsal digital nerves, one for
the medial side of the big toe and the other for the second
interdigital cleft. The lateral terminal branch of the superficial
peroneal nerve also divides into two dorsal digital nerves for the
third and fourth interdigital clefts

22. Superficial peroneal nerve

23. B-sensory supply:
 The sensory supply of the leg is mainly from:
 saphenous nerve(anteromedial,posteromedial areas)
 sural nerve(posterolateral)
 superficial and deep peroneal nerves(anterolateral)

24. Saphenous nerve(longest cutaneous nerve of the body)
 It is a branch of posterior division of femoral nerve. It pierces the deep fascia
on the medial side of the knee and accompanies the long saphenous vein,
either in front or behind it. It supplies the skin on the medial side of the
knee, leg, and medial border of the foot up to the ball of the big toe.

25. Saphenous Nerve

26. Sural nerve:
 It is a branch of the tibial nerve in the popliteal fossa.
 It pierces deep fascia in the middle of the leg and runs along the
short saphenous vein. It is joined by the sural (peroneal)
communicating nerve (a branch of common peroneal nerve) about 2
inches above the heel.
 After passing behind the lateral malleolus, the nerve runs forward
along the lateral border of foot, and ends in the skin on the lateral
side of the little toe. It supplies the skin of the lower lateral part of
the back of the leg, lateral border and adjoining part of the dorsum
of the foot, and the lateral side of the little toe

27. Sural Nerve

28. Areas of Sensory distribution along the Leg

29. Muscles:
 The fleshy mass of the leg is formed by a group of crural muscles,
which act on the foot.These muscles are tightly bound by fasciae
that compress them and aid in the return of blood from the legs.
The fasciae separate the crural muscles into anterior, lateral, and
posterior compartments.

30. Compartments of the leg:
1-Anterior Compartment of the Leg . (4muscles)
2-Posterior Compartment of the Leg. (7muscles):
a-superficial muscle groups(3 muscles).
b-deep muscle groups(4 muscles).
3-Lateral Compartment of the Leg. (2muscles):

31. 1-Anterior Compartment of the Leg(4muscles)
1-peroneus tertius.
2-extensor digitorum longus.
3-extensor hallucis longus.
4-tibialis anterior.
Nerve Supply: Deep Peroneal nerve

32. peroneus tertius.
 is a continuation of the belly of extensor digitorum longus.it’s origin
from Medial surface of lower one-third of fibula,It attaches to the
lateral border of the fifth metatarsal and everts the foot and
dorsiflexes the ankle.
 Maybe absent.

33. extensor digitorum longus
 Origin: Lateral condyle of tibia; shaft of fibula;
 Insertion: 2-5 phalanges as extensor expansion that
divides into three slips,The central slip attaches to the
base of the middle phalanx, while the two lateral slips
combine to insert into the base of the distal phalanx.
 Action:Extends toes; dorsiflexes foot;

34. extensor hallucis longus
 Origin: Anterior surface of middle of fibula
 Insertion: base of the distal phalanx
 Extends great toe; dorsiflexes foot

35. tibialis anterior
 Origin: Lateral condyle and lateral margin of proximal half
of tibia
 Insertion: base of the first metatarsal and adjacent part
of the first cuneiform bone.
 Dorsiflexes and inverts foot

36. Tibialis anterior

37. 3-Lateral Compartment of the Leg (2muscles):
1-Peroneus(fibularis) longus.
2-Peroneus Brevis.
Nerver supply: superficial peroneal nerve

38. Peroneus Longus
 Origin: Head and lateral surface of proximal two-thirds of
fibula
 Insertion: lateral side of the base of the first metatarsal
and the adjacent first cuneiform
 It everts and plantar flexes foot, Maintains concavity of
sole during toe-off and tiptoeing

39. Peroneus brevis
 Origin:Lateral surface of distal two-thirds of fibula
 Insertion: Base of metatarsal V
 Action:it everts foot

40. Peroneus Brevis

41. Posterior Compartment of the Leg (7muscles):
 a-superficial muscle groups(3 muscles).
 1-gastrocnemius
2-soleus
3-plantaris
 b-deep muscle groups(4 muscles).
1-flexor digitorum longus
2-flexor hallucis longus
3-tibialis posterior
4-popliteus
Nerve supply: Tibial nerve

42. Gastrocnemius
 It has 2 heads : medial and lateral heads
 Origin: Condyles and popliteal surface of femur; lateral supracondylar
line
 Insertion:The aponeuroses of gastrocnemius and soleus form the tendo-
achilles, which attaches to the middle third of the posterior surface of
the calcaneus .
 With soleus muscle,they are the main plantar flexor of the foot at ankle
joint, flexes knee; active in walking,running, and jumping

43. Gastrocnemius

44. Soleus
 Origin:Posterior surface of head and proximal one-fourth of fibula;
middle one-third of tibia;interosseous membrane
 Insertion:The aponeuroses of gastrocnemius and soleus form the
tendo-achilles, which attaches to the middle third of the posterior
surface of the calcaneus .

45. Soleus

46. Plantaris
 Origin:the lower end of the femur close to the lateral head of
gastrocnemius(lateral supracondylar line)
 Insertion:posterior surface of the calcaneus medial to the tendo-
achilles.
 It’s commonly used as tendon graft.

47. Plantaris

48. flexor digitorum longus
 Origin:posterior surface of the tibia and from the fascia covering
tibialis posterior.
 Insertion:bases of the terminal phalanges of the lateral toes(2-5).
 It flexes the toes and assists in plantar flexion of the ankle joint

49. flexor hallucis longus
 Origin:posterior surface of the shaft of the fibula,the posterior
intermuscular septum and the fascia covering tibialis posterior
 Insertion: base of the distal phalanx of the great toe .
 Action: powerful flexor of the hallux, Plantar flexion at the ankle
joint

50. tibialis posterior
 Origin:Posterior surface of proximal half of tibia, fibula, and
interosseous membrane
 Insertion: tuberosity of the navicular and by small slips to the other
tarsal bones(metatarsals II–IV)
 Action:Together with tibialis anterior its action is to invert the foot,weak
plantar flexor of the ankle joint

51. popliteus
 Origin:lateral condyle of femur,lateral meniscus
 Insertion:proximal shaft of tibia
 Action:flex and medially rotates leg.

52. Anatomy of the Blood Vessels
 A-Arteries:
 In the leg proper, the three most significant arteries are the
anterior tibial, posterior tibial, and Peroneal(fibular) arteries
 Popliteal Artery:
 It is the continuation of femoral artery. It begins at the adductor
hiatus (an osseo-aponeurotic opening in the adductor magnus at the
junction of middle one-third and lower one-third of the thigh),
crosses the floor of popliteal fossa from the medial to lateral side
to reach the lower border of the popliteus where it terminates by
dividing into anterior and posterior tibial arteries

53.  Branches
 These are divided into three groups—cutaneous, muscular,and articular (genicular).
1. Cutaneous branches: They pierce the roof and supply the overlying skin.
2. Muscular branches: They are large and several in number.
 The upper branches (two or three in number) supply
 adductor magnus and hamstring muscles. One or two of them anastomose with the
fourth perforating artery.
 The lower muscular branches supply the triceps surae muscles (i.e., two heads of
gastrocnemius and soleus)and plantaris (sural arteries 4-5 arteries)
3. Genicular (articular) branches :They are
 five in number and supply the knee joint.
 (a) Superior medial and lateral genicular arteries: They wind around the
corresponding side of the femur immediately above the corresponding femoral
condyles
 (b) Inferior medial and lateral genicular arteries: They wind around the
corresponding tibial condyles and pass deep to the corresponding collateral
ligaments
 (c) Middle genicular artery: It pierces the oblique popliteal ligament of the knee to
supply the cruciateligaments and synovial membrane of the knee joints.

54. Anastomosis around knee joint
 It is an arterial anastomosis around the knee joint formed by the branches
of popliteal, anterior tibial and posterior tibial, femoral, andprofund
 The anastomosis takes place as follows :
 1. Superior medial genicular artery anastomosis with the descending
genicular branch of the femoral artery and inferior medial genicular
artery.
 2. Inferior medial genicular artery anastomosis with the superior medial
genicular artery and saphenous artery—abranch of the descending
genicularartery (a branch of femoral artery).
 3. Superior lateral genicular artery anastomosis with the descending
branch of the lateral circumflex femoral artery and inferior lateral
genicular artery.
 4. Inferior lateral genicular artery anastomosis with the superior lateral
genicular artery, anterior and posterior recurrent branches of the anterior
tibial artery, and circumflex fibular branch of posterior tibial artery.a
femoris arteries

55. Anastomosis around knee joint

56. ANTERIOR TIBIAL ARTERY
 The anterior tibial artery is the main artery of the anterior
compartment of the leg.
 The blood supply to the anterior compartment of the leg is
reinforced by the perforating branch of peroneal artery. Therefore,
the size of peroneal artery is inversely proportional to that of the
anterior tibial artery. The anterior tibial artery is accompanied by
two venae comitantes
 It begins in the back of the leg at the lower border of popliteus,
enters the anterior compartment by passing forward between the
two heads of the tibialis posterior, through an opening in the upper
part of the interosseous membrane. In the anterior compartment, it
runs vertically downward to a point midway between the medial
and lateral malleoli, where it enters the foot and changes its name
to dorsalis pedis artery, which ends near the web between the big
and second toes

57.  Relations
 In the upper one-third of the leg it lies between the tibialis anterior
and extensor digitorum longus.
 In the middle one-third of the leg it lies between the tibialis
anterior and extensor hallucis longus.
 In the lower one-third of the leg it lies between extensor hallucis
longus and extensor digitorum longus. It is crossed from the lateral
to medial side by the tendon of extensor hallucis longus. As a
result, the deep peroneal nerve lies lateral to it in its upper one-
third and lower one-third, and anterior to it in its middle one-third

58. Branches:
1. Anterior and posterior tibial recurrent arteries: They take
part in the arterial anastomosis around the knee joint.
2. Muscular branches to adjacent muscles.
3. Anterior medial and anterior lateral malleolar arteries:
They take part in the anastomosis around the ankle joint

59. Anterior tibial artery

60. Posterior Tibial Artery
 It is the larger of the two terminal branches of the popliteal artery
because its branches not only supply the posterior compartment but
also the lateral compartment of the leg and the sole of the foot.
 It begins at the lower border of popliteus, between the tibia and
fibula, deep to gastrocnemius and enters the back of the leg by
passing deep to the tendinous arch of soleus.
 In the leg, it runs downward and slightly medially to reach the
posteromedial side of the ankle, midway between the medial
malleolus and the medial tubercle of calcaneum
 It terminates deep to the flexor retinaculum by dividing into a large
lateral plantar artery and a small medial plantar artery

61. Branches:
1. Peroneal (fibular) artery: It is the largest and most important branch of
the posterior tibial artery
 2. Muscular branches: To the muscles of posterior compartment.
 3. Nutrient artery to tibia: It is the largest nutrient artery in the body. It
enters the nutrient foramen of tibia below the soleal line.
 4. Circumflex fibular artery: It encircles the lateral side of the neck of the
fibula.
 5. Communicating branch: It joins with the similar branch of peroneal
artery about 5 cm above the ankle.
 6. Medial malleolar branch: It passes toward the medial malleolus.
 7. Calcaneal branch: It pierces the flexor retinaculum and supplies soft
tissues of the heel.
 8. Terminal branches: These are medial and lateral plantar arteries of the
sole

62. PERONEAL ARTERY
 It is the largest and most important branch of the posterior tibial
artery. It provides blood supply to the posterior and lateral
compartments of the leg.
 It arises 2.5 cm below the lower border of popliteus
 It runs obliquely toward the fibula and then descends along the
medial crest of the fibula in a fibrous canal between tibialis
posterior and flexor hallucis longus. Now it passes behind the
inferior tibiofibular and ankle joints, and ends on the lateral
surface of calcaneus and terminates by giving the lateral calcaneal
arteries

63. Branches:
 1. Muscular branches to the posterior and lateral compartments of
the leg.
 2. Nutrient artery to the fibula.
 3. Communicating branch: It joins with similar branch of the
posterior tibial artery about 5 cm above the ankle.
 4. Perforating branch: It is large and pierces interosseous
membrane about 5 cm above the ankle, appears in the anterior
compartment of the leg, and terminates by anastomosing with the
lateral malleolar branches of the anterior tibial and dorsalis pedis
arteries.
 5. Lateral calcaneal artery: It is a terminal branch which takes part
in the formation of lateral malleolar plexus

64. Peroneal(fibular) artery

65. B-veins:
 There are deep and superficial veins with anastomoses between them
I. Superficial Veins
 1. The dorsal venous arch is often visible through the skin on the dorsum
of the foot. It collects blood from the toes and more proximal part of the
foot, and has numerous anastomoses similar to the dorsal venous network
of the hand. It gives rise to the following two veins.
 2. The small (short) saphenous vein arises from the lateral side of the arch
and passes up that side of the leg as far as the knee. There, it drains into
the popliteal vein.
 3. The great (long) saphenous vein, the longest vein in the body, arises
from the medial side of the arch and travels all the way up the leg and
thigh to the inguinal region. It empties into the femoral vein slightly
inferior to the inguinal ligament.. Portions of this vein are commonly used
as grafts in coronary bypass surgery. The great and small saphenous veins
are among the most common sites of varicose veins

66.  II. Deep Veins
 1. The deep plantar venous arch receives blood from the toes and gives rise to
lateral and medial plantar veins on the respective sides.The lateral plantar vein
gives off the peroneal(fibular) veins, then crosses over to the medial side and
approaches the medial plantar vein. The two plantar veins pass behind the medial
malleolus of the ankle and continue as a pair of posterior tibial veins.
 2. The two posterior tibial veins pass up the leg embedded deep in the calf
muscles. They converge like an inverted Y about two-thirds of the way up the
tibia.
 3. The two peroneal (fibular) veins ascend the back of the leg like a Y.
 4. The popliteal vein by convergence of these two inverted Ys.
 5. The two anterior tibial veins travel up the anterior compartment of the, and
then flow into the popliteal vein.
 6. The femoral vein is a continuation of the popliteal vein into the thigh. It drains
blood from the deep thigh muscles and femur.
 7. The deep femoral vein drains the femur and muscles of the thigh supplied by
the deep femoral artery. It receives four principal tributaries along the shaft of
the femur and then a pair of circumflex femoral veins that encircle the upper
femur, then finally drains into the upper femoral vein

67. Superficial,Deep veins of lower limb

68. C-lymphatic
 There are both superficial and deep lymphatics. The superficial
lymphatics accompany the superficial veins. Those with the great
saphenous vein terminate in superficial inguinal nodes,which drain
into deep inguinal nodes. Lymphatics following the short saphenous
vein drain into nodes in the popliteal fossa. The deep lymphatics
accompany arteries in the muscle compartments.Those from the leg
and foot drain into the popliteal nodes whence lymphatics ascend
with the femoral artery to the deep inguinal nodes whose efferents
pass to the external iliac group.

69. 9-Keys of Leg anatomy in Reconstructive
surgery
Mathes and Nahai classification:
 Type I: one main vascular pedicle (andgastrocnemius muscles)
 Type II: have a dominant pedicle and a minor pedicle (soleus
muscles)
 Type III: have two main vascular pedicles, each arising from a
separate regional vessel (example rectus abdominus and gluteus
maximus muscles)
 Type IV: have multiple segmental vascular pedicles (example
sartorius and tibialis anterior muscles)
 Type V: have one main vascular pedicle and multiple secondary
pedicles (Latissimus dorsi and pectoralis major muscles)

70. Types of Muscle flaps (Mathes and Nahai)

71. Radiograph of Gastrocnemius muscle(left),Sartorius(right)

72. The Angiosome Concept:
 In 1987 Taylor defined the Angiosome as “a three
dimensional composite unit of tissue supplied by a given
source artery”.
 The composite building block of tissue contains muscle,
nerve, connective tissue, bone and the overlying skin.
Taylor divided the body into 40 angiosomes based on
named source arteries .
 The angiosome concept and the idea that adjacent
angiosomes are linked provide the basis for tissue
transfers, particularly microsurgical tissue transfers

73. anterior aspect of the leg Red circles identify
musculocutaneous perforators
Blue circles identify septocutaneous perforators
Anatomic territories of the cutaneous blood
supply
are numbered:
1) Lateral inferior genicular artery
2) Anterior tibial recurrent branch of the
anterior tibial artery
3) Medial inferior genicular artery
4) Descending genicular artery
5) Anterior tibial artery
6) Posterior tibial artery
7) Peroneal artery

74. The posterior aspect of the leg
Red circles identify musculocutaneous
perforators Blue circles identify septocutaneous
perforators Anatomic territories of cutaneous
blood supply are numbered:
1) Descending genicular artery
2) Lateral inferior genicular artery
3) Medial and lateral superficial sural
arteries
4) Anterior tibial artery
5) Posterior tibial artery
6) Peroneal artery
7) Medial calcaneal artery
8) Lateral calcaneal artery

75. types of perforating vessels to the skin
 1. Musculocutaneous perforators: this type of perforator is
the cutaneous vessel after penetrating underlying muscle.
Through intramuscular dissection, longer vascular pedicle
can be obtained.
 2. Septocutaneous perforators: this type of perforator is
the cutaneous vessel after piercing the fascial septum
between muscles. Through intraseptal dissection, the
perforator can be traced to its deep origin from the
source artery

76. “A wise Plastic
surgeon said”

77. Thank you