1. LEG
IN 15 QUESTIONS
Kaan Yücel M.D., Ph.D.
1.March.2013 Friday

2. INTRODUCTION TO LEG Regio cruris - Leg between knee & ankle joint
includes most of tibia & fibula
Distally, structures pass between the leg & foot mainly through tarsal tunnel on the posteromedial side of the ankle,
Except anterior tibial artery & ends of the deep and superficial fibular nerves

3. INTRODUCTION TO LEG Deep fascia of the leg Crural fascia
Two intermuscular septa pass, together with the interosseous membrane, divide the leg into
3 compartments
Anterior compartment
Lateral compartment
Posterior compartment

4. INTRODUCTION TO LEG
Inferiorly, two band-like thickenings of the fascia form retinacula that bind the tendons of the anterior compartment muscles, preventing them from bowstringing anteriorly during dorsiflexion of the joint:
Superior extensor retinaculum
Inferior extensor retinaculum

5. INTRODUCTION TO LEG Flexor Retinaculum
Between medial malleolus & calcaneus
Binds posterior leg’s deep muscles’ tendons to medial malleolus
Superior Peroneal Retinaculum
Connects the lateral malleolus to calcaneus
Binds the tendons of peroneus longus & brevis to lateral malleolus
Inferior Peroneal Retinaculum
Binds the tendons of the peroneus longus and brevis muscles to calcaneus

6. ANTERIOR
COMPARTMENT
OF THE LEG
IN 5 QUESTIONS

7. 1… anterior compartment of the leg
Dorsiflexor (extensor) compartment
Located anterior to the interosseous membrane
between the lateral surface of the shaft of tibia and medial surface of shaft of the fibula
anterior to the intermuscular septum that connects them.
Bounded anteriorly by the deep fascia of the leg and skin.

8. 2. Which muscles are in the anterior part of the leg?
Tibialis anterior
Extensor hallucis longus
Extensor digitorum longus
Fibularis tertius

9. 3… functions of the muscles in the anterior part of the leg?
Tibialis anterior
Dorsiflexes the foot at the ankle joint and inverts the foot at the intertarsal joints. During walking, provides dynamic support for the medial arch of the foot.
Extensor hallucis longus
Extends lateral four digits and dorsiflexes ankle
Extensor digitorum longus
Extends great toe and dorsiflexes ankle
Fibularis tertius
Dorsiflexes ankle and aids in eversion of foot

10. Anterior tibial artery
4. Which arteries are in the anterior part of the leg?
Anterior tibial artery
Passes forward into the anterior compartment of leg through an aperture in the interosseous membrane.
Begins at the inferior border of the popliteus muscle
@ ankle joint
midway between the malleoli
Name change  dorsalis pedis artery (dorsal artery of the foot).

11. Anterior tibial artery
4. Which arteries are in the anterior part of the leg?
Anterior tibial artery
Distally,
gives rise to
anterior medial malleolar artery anterior lateral malleolar artery
pass posteriorly around the distal ends of the tibia and fibula, respectively.

12. 5. Which nerves are in the anterior part of the leg?
Deep fibular (peroneal nerve)
anterior tibial artery
innervates all muscles in the anterior compartment;
[continues into the dorsal aspect of the foot] innervates the extensor digitorum brevis, first two dorsal interossei muscles, and supplies the skin between the great and second toes.

13. LATERAL
COMPARTMENT
OF THE LEG
IN 3 QUESTIONS

14. 1. Which muscles are in the lateral part of the leg?
Fibularis longus
Fibularis brevis

15. 2… functions of the muscles in the lateral part of the leg?
Everts foot and weakly plantarflexes ankle
Neurological Examination

16. 3. Which nerves are in the lateral part of the leg?
Superficial fibular (peroneal) nerve
Fibularis longus & fibularis brevis
Skin on the distal part of the anterior surface of the leg and dorsal areas of the foot and toes except for:
the web space between the great and second toes,

17. POSTERIOR
COMPARTMENT
OF THE LEG
IN 7 QUESTIONS

18. 1. superficial muscles of the posterior part of the leg
Gastrocnemius
Soleus
Plantaris

19. 2. ..deep muscles of the posterior part of the leg?
Popliteus
Flexor digitorum longus
Flexor hallucis longus
Tibialis posterior

20. 3… functions of the superficial muscles in posterior leg
Gastrocnemius:
Plantarflexes ankle when knee is extended; raises heel during walking; flexes leg at knee joint
Soleus:
Plantarflexes ankle independent of position of knee; steadies leg on foot

21. 4… functions of the deep muscles in the posterior leg
Popliteus acts on the knee joint
Unlocking the extended the initation of flexion
Others plantarflex the ankle with two continuing on to flex the toes.
Tibialis posterior:
Plantarflexes ankle; inverts foot

22. 5… arteries in the posterior part of the leg
Popliteal artery
Major blood supply to the leg and foot
Passes
into the posterior compartment of leg between the gastrocnemius and popliteus muscles.
under the tendinous arch formed between the fibular and tibial heads of the soleus muscle
@ posterior compartment of leg divides into anterior tibial artery & posterior tibial artery

23. 5… arteries in the posterior part of the leg
Posterior tibial artery
two major branches, the circumflex fibular artery and fibular artery:
Nutrient artery of tibia
Largest nutrient artery in the body
Arises from the origin of the anterior or posterior tibial artery.

24. 6… nerves in the posterior part of the leg
Tibial nerve
Passes
under the tendinous arch formed between fibular and tibial heads of the soleus muscle
vertically through the deep region of the posterior compartment of leg on the surface of tibialis posterior muscle with the posterior tibial vessels.

25. 6… nerves in the posterior part of the leg
Tibial nerve
Leaves the posterior compartment of leg at the ankle via tarsal tunnel behind the medial malleolus.
Enters the foot to supply most intrinsic muscles and skin.

26. 6… nerves in the posterior part of the leg
Tibial nerve
In the leg, gives rise to:
• branches that supply all the muscles in the posterior compartment of leg
• 2 cutaneous branches
sural nerve
&
medial calcaneal nerve