osteology, regional anatomy, radiologic anatomy

1. The Leg
Presented by
Dr. Maryna Kornieieva
Asst. of Anatomy
• Orthopedic anatomy
• Clinical anatomy
• Radiologic anatomy

2. Leg: Orthopedic Anatomy

3. Proximal leg: bones
Anterior view: tibia(T) and fibula(F) Posterior view: tibia(T) and fibula(F)
Medial tibial condyle
Medial tibial condyle
Lateral tibial condyle
Tibial tuberosity
(patellar ligament)
Intercondilar eminence
Fibular Articular facet
Soleal line
Medial surface
(subcutaneous)
Anterior border
Medial borderLateral border
(interosseous)
Lateral surface Posterior surface
Head
Styloid process
Neck
T
T
F

4. Proximal Tibiofibular Joint
The proximal TF joint is synovial
and of little clinical consequence
(opposed to the fibrous distal TF
joint which is vital to ankle stability)
Proximal
Tibiofibular Joint
Distal
Tibiofibular Joint
Interosseous
membrane
Type: synovial, plane, gliding joint
Type: fibrous joint
Movements: small amount
Movements: small amount
Articulation: lateral condyle of the
tibia and the head of the fibula
Articulation: fibular notch at
the lower end of the tibia and
the lower end of the fibula.
Ligaments:
Anterior and posterior
ligaments

5. Clinical notes
The fibular neck has the common peroneal
(fibular) nerve running around it that may be
injured by fracture, oedema or compression.
Tibial plateau fractures occur due to a fall from a height, direct trauma,
valgus or varus injuries (usually valgus due to lateral trauma causing lateral
condyle injury) and minor falls in an osteoporotic patient.
Anterior
Intercondilar
area
Posterior Intercondylar area
Tibial plateau
Intercondilar eminence
CT (MIP)

6. Clinical notes
The tuberosity
may avulse
anteriorly or
fragment.
It usually
responds to
conservative
treatment.
Osgood-Schlatter’s disease -
(epiphysitis) is due to avulsion and
inflammation of the soft young tibial
tuberosity epiphysis subject to the pull
of the powerful quadriceps muscle.

7. Tibial shaft fractures
1) It is a weight-bearing bone with little
surrounding muscle anteromedially (that
would improve blood supply for healing).
2) There are only skin and periosteum
over the bone increasing the chance of an
open fracture.
3) The fibula may hold the ends of a
tibial fracture apart, making healing less
likely.
Transverse
(hit by a car)
Spiral
(torsion injury)
Oblique
(direct trauma plus
indirect torsion)
Clinical notes: peripheral pulses must be checked early. If the foot is pale and
pulseless, immediate temporary reduction is required.
Treatment: Conservative treatment may
be used for stable fractures but otherwise,
internal fixation by intramedullary nail or
plate is used. Isolated tibial fractures may
require fibular osteotomy.
Difficulties:

8. Distal leg: bones
Eversion injuries to the ankle may cause high fibula fractures (even at
the fibular neck) due to sprining of the bone around the distal TF joint as
the fulcrum.
Medial malleolus
Posterior
Anterior
Malleolar
fossa
Tibialis
posterior
groove
Flexor
hallucis
longus
groove
Distal
TF joint
Peroneus
longus
groove
Add X-ray
Ankle mortise
Lateral malleolus

9. Distal Tibiofibular Joint
The bony mortise keeps the ankle joint very solid but
depends on an intact distal tibiofibular joint (if it is
not intact then there can be lateral shift of the talus).
Ligaments of the Distal TF joint:
Interosseous
ligaments
Anterior inferior
tibiofibular lig.
Posterior inferior
tibiofibular lig.
Posterior talo-
fibular ligament Anterior talo-
fibular ligament
Calcaneo-fibular lig

10. Clinical notes
Rotational ankle injuries do often
cause malleolar fractures: medial one
is stressed in hyperinversion, while
lateral one – in hypereversion.
Cross-sectional computed
tomography scan showing
measurement of the anterior,
central, and posterior width of the
distal tibiofibular joint (normal).
Diastasis is complete disruption of the
strong fibrous distal tibiofibular joint. It
indicates significant trauma and unstable
ankle (a serious injury). This allows lateral
shift of the talus and needs fixation.

11. Leg: Clinical Anatomy

12. The Leg: regions
is the part of the lower limb between the knee and ankle joint
Anterior region of the leg Posterior region of the leg

13. Surface Anatomy of the Leg
Anterior region Posterior region

14. Superficial veins
Long (greater) saphenous vein forms
in front of the medial malleolus and
ascends up along the medial side of the
lower limb till it opens into the femoral
vein 3-4 cm below the inguinal ligament
(saphenous hiatus).
Short (lesser) saphenous vein
forms behind the lateral malleolus
and goes toward the popliteal fossa,
there it tributes into the popliteal
vein.
There are numerous
perforating veins
(30-40) connecting
superficial veins with
the deep along their
way. The valves
inside the perforating
veins allow one-
directed blood flow
(from superficial veins
to the deep).
The vascular wall of the superficial veins is thin and is able to resist only
the minimal blood pressure. In case of development of venous
hypertension, the wall dilates and become tortures.
This state is known as varices, or varicose disease.

15. Compartments of the leg
Deep fascia attaches to the periosteum of
the anterior and medial borders of the tibia
Anterior
Crural
Intermuscular
Septum
Posterior
Crural
Intermuscular
Septum
Investing Deep Fascia
Transverse Intermuscular Septum
Transverse intermuscular septum separates superficial
and deep muscles of the posterior compartment and
gives rise to retinacula around the ankle.

16. Leg: compartments
Muscles:
1. tibialis anterior,
2. extensor digitorum longus,
3. extensor hallucis longus,
4. peroneus tertius;
Blood supply: Anterior tibial
artery
Nerve supply: Deep peroneal
nerve
Superficial muscles:
1. gastrocnemius,
2. plantaris, and
3. soleus
Deep muscles:
Popliteus, flexor digitorum longus,
flexor hallucis longus, and tibialis
posterior.
Blood supply: Posterior tibial artery
Nerve supply: Tibial nerve
Anterior Compartment (AC) Posterior Compartment (PC) Lateral Compartment (LC)
Muscles:
1. Peroneus longus,
2. Peroneus brevis;
Blood supply: Perforating
branches from the fibular
(peroneal) artery
Nerve supply: Superficial
fibular (peroneal) nerve

17. AC muscles: Tibialis Anterior
Origin:
Lateral surface of
shaft of tibia and
interosseous
membrane.
Insertion:
Medial cuneiform
and base of 1st
metatarsal bone.
Nerve Supply:
Deep peroneal
nerve
Action:
Extends foot at ankle joint; inverts foot at
subtalar and transverse tarsal joints; holds
up medial longitudinal arch of foot.

18. Extensor Digitorum Longus
Action:
Extends toes;
extends foot
at ankle joint
Insertion:
Extensor
expansion
of lateral
four toes
Origin:
Anterior surface of
shaft of fibula
Nerve Supply:
Deep peroneal nerve

19. Extensor Hallucis Longus
Action:
Extends big toe; extends
foot at ankle joint; inverts
foot at subtalar and
transverse tarsal joints
Insertion:
Base of distal
phalanx of
great toe
Origin:
Anterior surface of shaft of fibula
Nerve Supply:
Deep peroneal
nerve

20. Peroneus (Fibularis) Tertius
Origin:
Anterior surface of
shaft of fibula
Insertion:
Base of 5th metatarsal bone
Nerve Supply:
Deep peroneal
nerve
Action:
Extends foot at
ankle joint;
everts foot at
subtalar and
transverse tarsal
joints.

21. Anterior compartment: vessels
Anterior Tibial Artery arises from the
popliteal artery within the cruropopliteal canal.
It quits the canal via the anterior outlet (the opening in
interosseous membrane) and descends to the foot with
the deep fibular nerve.
Branches:
1) Anterior tibial recurrent
artery (ascends to the
genicular anastomosis);
2) Muscular branches;
3) Anterior (medial and lateral)
malleolar arteries (descend to
the ankle).
It continues with the dorsal artery of foot.

22. Anterior compartment: nerves
Deep fibular nerve
It one of the two divisions of the common fibular nerve.
Course: It passes through the
anterior crural intermuscular septum
and descends toward the ankle deep
to the extensor digitorum longus.
Supplies:
On the leg - all muscles of the anterior
compartment;
On the foot - extensor digitorum
brevis, first two dorsal interossei
muscles, + the skin between the great
and second toes.

23. Deep Fibular Nerve Injury
The deep fibular nerve could be damaged as a part of the common peroneal nerve, because last one is extremely
vulnerable to injury as it winds around the neck of the fibula.
Injury to the common peroneal nerve (as well as the deep fibular
itself) causes foot drop.

24. Anterior Compartment
of the Leg Syndrome
Compartment syndrome occurs with a rise in
pressure within a compartment due to many
causes but often unrecognized trauma.
Symptoms:
• Progressive ischemic pain;
• Numbness and paraesthesia;
• Swelling and induration in the leg;
• Pale foot.
It is required urgent fasciotomy to avoid
muscle necrosis and distal ischemia.

25. PC muscles
Superficial Deep
Gastrocnemius
Soleus
Plantaris
Tibialis Posterior
Popliteus
Flexor Digitorum Longus
Flexor Hallucis Longus

26. Gastrocnemius
Origin:
Lateral head from
lateral condyle of
femur and medial
head from above
medial condyle
Insertion:
Via tendo calcaneus into
posterior surface of calcaneum. Nerve Supply:
Tibial nerve
Action:
• Plantar flexes
foot at ankle
joint;
• flexes knee
joint.

27. Soleus
Insertion:
Via tendo calcaneus
into posterior surface
of calcaneum
Action:
Together with
gastrocnemius and
plantaris is powerful
plantar flexor of
ankle joint; provides
main propulsive force
in walking and
running
Nerve Supply:
Tibial nerve
Origin:
Shafts of tibia
and fibula

28. Ruptured Tendo Calcaneus
Common in middle-aged tennis players
The rupture occurs at its narrowest part, about
5 cm above its insertion.
Symptoms:
• Acute pain;
• Impossible plantar flexion;
• Palpable gape above calcaneus
N
The tendon should be sutured as soon as possible and the leg
immobilized with the ankle joint plantar flexed and the knee joint flexed.

29. Plantaris
Nerve Supply:
Tibial nerve
Action:
Plantar flexes foot at ankle joint;
flexes knee jointOrigin:
Lateral
supracondylar
ridge of femur
Insertion:
Posterior surface of
calcaneum
Plantaris

30. Popliteus
The popliteus muscle arises inside the capsule of the
knee joint and is inserted into the upper part of the posterior
surface of the tibia.
The tendon separates the lateral ligament of the knee joint
from the lateral meniscus so that the meniscus is not tethered
to the ligament and is freer to move and adapt to the surfaces
of the condyle of the femur and the tibia.
The popliteus muscle is
responsible for
“unlocking” the knee joint.

31. Tibialis Posterior
Nerve Supply:
Tibial nerve
Origin:
Posterior surface
of shafts of tibia
and fibula and
interosseous
membrane
Action:
Plantar flexes foot at ankle
joint; inverts foot at subtalar
and transverse tarsal joints;
supports medial longitudinal
arch of foot
Tibialis
posterior
groove
Flexor retinaculum
Insertion:
Tuberosity of navicular bone
and other neighboring bones

32. Tarsal Tunnel
Boundaries: Contents:
• Tibialis posterior tendon
• Flexor digitorum longus
tendon
• Posterior tibial artery
• Posterior tibial vein
• Tibial nerve
• Flexor hallucis longus
tendon
• roof: flexor retinaculum
• floor: medial surfaces of the talus and calcaneus

33. Flexor Digitorum Longus
Nerve Supply:
Tibial nerve
Action:
Flexes distal
phalanges of
lateral four toes;
plantar flexes
foot at ankle
joint;
supports medial
and lateral
longitudinal
arches of foot.
Origin:
Posterior surface of
shaft of tibia
Insertion:
Bases of distal
phalanges of
lateral four toes L R

34. Flexor Hallucis LongusOrigin:
Posterior surface of
shaft of fibula Nerve Supply:
Tibial nerve
Action:
Flexes distal phalanx
of big toe; plantar
flexes foot at ankle
joint; supports medial
longitudinal arch of
foot.
Insertion:
Base of distal
phalanx of big
toe.
L R

35. Posterior compartment: vessels
Tibialis Posterior artery
Peroneal (fibular) artery
Passes downward along the posterior
surface of the tibialis posterior,
accompanied by deep veins and the
tibial nerve.
Branches:
• Peroneal artery
• Muscular branches
• Nutrient artery to the tibia.
• Anastomotic branches
• Medial and lateral plantar arteries
It descends behind the fibula, either within
the substance of the flexor hallucis longus
muscle or posterior to it.
• Muscular branches
• Nutrient artery to the fibula
• Anastomotic branches (ankle joint)
• Perforating branch (pierces the
interosseous membrane to reach the
muscles of the lateral compartment of
the leg).
Branches:
1 - a. poplitea; 2 - a. genu sup. lateralis; 3 - a. genu inf. lateralis; 4 - a. peronea (fibularis); 5 - rami malleolares tat.; 6 - rami
calcanei (lat.); 7 - rami calcanei (med.); 8 - rami malleolares mediales; 9 - a. tibialis post.; 10 - a. genu inf. medialis; 11 - a.
genu sup. medialis.

36. Palpation of the posterior tibial artery
The point: posterior and inferior to the medial
malleolus.
Goal: assessing a patient for peripheral vascular
disease.

37. Deep Veins: Thrombosis
It passes rapidly to the heart and lungs, causing pulmonary embolism, which is often fatal.
DVT - is the formation of
a blood clot (thrombus)
within a deep vein,
predominantly in the legs.
Non-specific signs may include pain,
swelling, redness, warmness, and
engorged superficial veins.
• Older age;
• Major surgery and orthopedic surgery;
• Inactivity and immobilization, as with orthopedic casts, sitting, travel,
bed rest, and hospitalization;
• Trauma, minor leg injury, and lower limb amputation;
• Blood disorders; and others.
Risk factors:

38. Tibial nerve
• Muscular branches: soleus, flexor digitorum
longus, flexor hallucis longus, and tibialis
posterior.
• Cutaneous: The medial calcaneal branch
supplies the skin over the medial surface of the
heel.
• Articular branch to the ankle joint.
• Medial and lateral plantar nerves
Branches on the leg:
The cutaneous innervation of the terminal
branches of the sciatic nerve.

39. Tarsal Tunnel Syndrome
Symptoms:
• Pain and tingling in and around ankles and
sometimes the toes
• Swelling of the feet
• Painful burning, tingling, or numb sensations in
the lower legs. Pain worsens and spreads after
standing for long periods; pain is worse with
activity and is relieved by rest.
• Pain radiating up into the leg, and down into
the arch, heel, and toes
• Pain along the Posterior Tibial nerve path
• Burning sensation on the bottom of foot that
radiates upward reaching the knee
• "Pins and needles"-type feeling and increased
sensation on the feet.
TT - is a compression
neuropathy and painful foot
condition in which the tibial
nerve is compressed as it travels
through the tarsal tunnel.
Definition:

40. Peroneus Longus
Origin:
Lateral surface
of shaft of
fibula
Insertion:
Base of 1st
metatarsal
and the medial
cuneiform
Nerve
Supply:
Superficial
peroneal nerve Action:
Plantar flexes foot at
ankle joint; everts foot
at subtalar and
transverse tarsal joints;
supports lateral
longitudinal and
transverse arches of
foot.

41. Peroneus Brevis
Action:
Plantar flexes foot
at ankle joint; everts
foot at subtalar and
transverse tarsal
joint; supports
lateral longitudinal
arch of foot.
Origin:
Lateral surface of
shaft of fibula
Nerve Supply:
Superficial
peroneal nerve
Insertion:
Base of 5th
metatarsal
bone

42. Tenosynovitis and Dislocation of the Peroneus
Longus and Brevis Tendons
Tenosynovitis can affect
the tendon sheaths of
the peroneus longus and
brevis muscles as they
pass posterior to the
lateral malleolus.
Tendons of peroneus
longus and brevis may
dislocate forward.
For this condition to
occur, the superior
peroneal retinaculum
must be torn.
PL – peroneus longus; PB – peroneus brevis; SPR – superior peroneal retinaculum; IPR – inferior peroneal retinaculum.

43. Lateral compartment: vessels
Numerous branches from the peroneal (fibular)
artery, which passes through posterior compartment
of the leg, pierce the posterior fascial septum, and
supply the peroneal muscles.
NC-MRA (inflow inversion recovery) shows normal arterial
vasculature of the lower extremities. PA, popliteal artery;
AT, anterior tibial arteries; PT, posterior tibial arteries; and
PER, peroneal arteries.

44. Nerves The superficial peroneal nerve is one of the
terminal branches of the common peroneal nerve
Muscular:
to the peroneus longus and brevis
Branches
Cutaneous:
• lower part of the front
of the leg;
• dorsum of the foot;
• dorsal surfaces of the
skin of all the toes
(except the adjacent
sides of the first and
second toes and the
lateral side of the little
toe).
It arises in the substance of the
peroneus longus muscle on the
lateral side of the neck of the
fibula, and then descends between
the peroneus longus and brevis
muscles.

45. Leg: Radiologic Anatomy

46. Sectional Anatomy of the Leg

48. T1-weighted axial
image through the
upper leg
(fatty tissues bright,
fluids dark)
MRI

49. T2W axial MR image through the upper leg
Note increased signal of all the muscles, in
all the compartments.
This is edema.
There is also some edema of the
subcutaneous tissues.
It is very unusual for a trauma, for
example, to present with edema in all
compartments.
There are no fluid collections within the
muscles, but notice the perifascial fluid
collections.
(fatty tissues dark, fluids bright)