Anatomy of Ankle and Foot

1. Anatomy of Ankle and Foot

2. Overview • Bones of Ankle and Foot • Functions   • Blood Vessels and Nerves • Parts of the Foot • Arches of the Foot • Joints • Tendons and Ligaments • Muscles • Common Injuries

3. Ankle and Foot • The ankle and foot are composed of 26 bones connected by muscles, tendons, and ligaments; and a network of blood vessels, nerves, skin, and soft tissue

4. Bones of the Ankle and Foot • Ankle: 7 tarsal bones: talus, calcaneus (heel bone), navicular, cuboid, medial cuneiform, intermediate cuneiform, and lateral cuneiform • Foot: 5 metatarsal bones • Proximal base, shaft, and distal head • Toes: 14 phalanges - Each great toe has only two phalanges, one proximal and one distal. The second through fifth toes each have three phalanges: proximal, middle and distal

6. Functions of Ankle and Foot • Absorb shock and impact to the body as the foot contacts the ground • Ability to adapt to different surfaces • Provide a base of support for the body • Covert torque from the lower extremity • Become a lever for forward propulsion • Provide proprioception to the lower extremity

7. Blood Vessels • Primary blood supply to the foot: • Anterior Tibial Artery • Posterior Tibial Artery • Peroneal Artery

8. Nerves • Primary nerve to the foot, Tibial Nerve, enters the sole of the foot by running behind medial malleous • Supplies sensation to the toes and sole of the foot and controls the muscles of the sole of the foot

9. Parts of the Foot • Rearfoot is comprised of the talus and calcaneus • Midfoot is comprised of the navicular, cuboid and three cuneiforms  • Forefoot is comprised of the metatarsals and the phalanges

10. Arches of the Foot • The arrangement of bones produces three strong arches • Transverse Arch (A) • Medial Longitudinal Arch (B) • Lateral Longitudinal Arch (C) • The arches assist in absorbing shock loads and balancing the body

11. Tendons, Joints, and Ligaments of Ankle • Achilles Tendon/Calcaneal Tendon • Talotibial/Talocrural Joint • Subtalar Joint • Medial Collateral Ligament (Deltoid Ligament) • Lateral Collateral Ligament

12. Achilles Tendon • Achilles tendon is the most important tendon for walking, running, and jumping • It attaches the gastrocnemius and soleus to the calcaneus (heelbone) and permits plantarflexion

13. Anatomy of Tibia and Fibula

14. Tibia • Strongest and largest bone of the lower leg • Medial bone • It bears weight and the bone creates the medial malleoli (the bump on the inside of your ankle) which is the medial aspect of the Mortise or the (hole) that the talus lies within

15. Fibula • Smaller lateral bone of the lower leg • Not vital for weight bearing • It comprises the lateral (outside) aspect of the malleoli and makes up the lateral aspect of the Mortise

16. Talotibial/Talocrural Joint • The formation of the mortise (a hole) by the medial malleoli (Tibia) and lateral malleoli (fibula) with the talus lying in between them • Synovial, hinge joint • Permits movement in Sagital Plane • Plantarflexion and Dorsiflexion

17. Subtalar Joint • The articulation between the Talus and the Calcaneus • Synovial, plane joint • Permits movement in Frontal Plane • Inversion and Eversion • Inversion-plantarflexion and adduction • Eversion-dorsiflexion and abduction

18. Medial Collateral Ligament • Located on the medial aspect of the foot • Commonly called Deltoid Ligament • Connect the tibia to the talus and calcaneus • Provides medial stability • This ligament prevents eversion of the ankle • It is the most difficult ligament in the foot to sprain

19. Lateral Collateral Ligament • Weaker than the medial collateral ligament and comprises three separate bands: the anterior and posterior talofibular and the calcaneofibular ligaments • Connect the fibula to the calcaneus • Provides lateral stability • Prevents inversion of the ankle • The anterior talofibular and the calcaneofibular ligaments are the most frequently injured when the ankle is sprained, which usually is an inversion injury while the ankle is in its most unstable position of plantar flexion.

20. Invertors of the Ankle “Tom, Dick, and Harry muscles” • Tibialis Posterior • Flexor Digitorum Longus • Flexor Hallucis Longus

21. Tibialis Posterior Deep to soleus O: Posterior Tibia and Fibula I: Navicular, Cuneiform, Cuboid, and Bases of 2nd-4th Metatarsals A: • Inversion of Ankle • Plantarflexion of Ankle Integrated Function: • Assists in eccentric deceleration of subtalar joint eversion

22. Flexor Digitorum Longus O: Middle Posterior Tibia I: Plantar Surface of Toes #2-5 A: • Flexion of Toes #2-5 • Inversion of Ankle Integrated Function: • Assists in eccentric deceleration of ankle eversion • Assists in eccentric deceleration of extension of toes #2-5

23. Flexor Hallucis Longus O: Posterior, middle half of Fibula I: Plantar Surface of the Big Toe (hallux) A: • Flexion of the Big Toe • Inversion of Ankle Integrated Function: • Assists in eccentric deceleration of extension of the big toe • Assists in eccentric deceleration of ankle eversion • Assists in dynamic stabilization of the big toe

24. Peroneal Muscles • All originate on the Fibula • All Evert the ankle • Peroneus Longus • Peroneus Brevis • Peroneus Tertius

25. Peroneus Longus O: Head and lateral shaft of Fibula I: Base of 1st metatarsal and first cuneiform (plantar surface) A: • Eversion of Ankle • Plantarflexion of Ankle

26. Peroneus Brevis O: Lower 2/3 of lateral shaft of fibula I: Base of 5th metatarsal A: • Eversion of Ankle • Plantarflexion of Ankle

27. Peroneus Tertius O: Anterior distal fibula I: Base of 5th metatarsal A: • Eversion of Ankle • Dorsiflexion of Ankle (weak)

28. Integrated Function of Peroneal Muscles • Assist in eccentric deceleration of ankle inversion • Assists in eccentric deceleration of ankle dorsiflexion (peroneus longus and brevis)

29. Summary Ankle Invertors: • Tibialis Anterior • Tibialis Posterior • Flexor Digitorum Longus • Flexor Hallucis Longus Ankle Evertors: • Peroneus Longus • Peroneus Brevis • Peroneus Tertius

30. Specific Injuries • Ankle Injuries: Sprains • Caused by sudden inversion or eversion movements • Inversion Sprains • Most common and result in injury to the lateral collateral ligaments • With inversion sprains the foot is forcefully inverted or occurs when the foot comes into contact w/ uneven surfaces • Occasionally the force is great enough for an avulsion fracture to occur with the lateral malleolus

31. Specific Injuries • http://www.youtube.com/watch?v=6EDcH3jPsyA

33. Specific Injuries • http://www.youtube.com/watch?v=Oy7EpeD8eBk

35. Prevention of Injury to the Ankle • Stretching of the Achilles tendon • Strengthening of the surrounding muscles • Proprioceptive training: balance exercises and agility • Wearing proper footwear

36. Prevention of Injury to the Ankle • Strength training allows the supporting musculature to stabilize where ligaments may no longer be capable of holding the original tension between bones of the joint • This will also help prevent reinjury

37. Neuromuscular Control Training • Can be enhanced by training in controlled activities • Uneven surfaces, BOSU, Rocker Boards, or Dynadiscs can also be utilized to challenge the individual

38. Proper Footwear • Footwear is something often overlooked but improper footwear can predispose someone with a foot condition such as pes planus (flat feet) to be more prone to having problems with their feet and ankles