Basic Anatomy of the Dancer's Ankle and Foot

Original Editor - Carin Hunter based on the course by Michelle Green-Smerdon
Top Contributors - Carin Hunter, Jess Bell, Kim Jackson, Wanda van Niekerk and Olajumoke Ogunleye

Tibia, Fibula and Talus

The ankle and foot are complex and detailed structures that bear the weight of the whole body, and are designed to showcase a beautiful work of art. The ankle and foot is a very complex system. This part of the body has to cope with high compressive and shearing forces and at the same time it has to offer a high degree of stability. The ankle is the kinetic link of the foot to higher up in the body and the foot is the body's interaction with the ground and has to control multi-axial motions occurring simultaneously.

Transverse-tarsal joint

The ankle is made up of three bones, the Tibia, Fibula and Talus and three joints, the transverse-tarsal joint which works together with the talocalcaneal joint, the talocalcaneal joint which controls inversion and eversion and the tibiotalar joint which helps with stability, flexion and extension.

Foot Summary

1. Hind foot
   1. Bones
      1. Talus
         1. This is the highest foot bone, there are no tendons attached to it, only the Deltoid ligament, it is a mostly cartilage surface, has a poor blood supply and therefore relatively poor healing.
      2. Calcaneous
      3. Lateral and medial malleolus
   2. Joints
      1. Tibiotalar Joint:
         1. The talus is at its widest anteriorly, meaning the joint is more stable in dorsiflexion.
         2. The conforming geometry of the tibiotalar joint is considered to contribute to the stability of the joint. In stance phase, the geometry of the joint alone is sufficient to provide resistance to eversion; otherwise stability is derived from the soft tissue structures.
      2. Subtalar joint:
         1. Absorbs rotational stress from higher up the body
      3. Transverse tarsal joint (combo of Talonavicular and CC joints) :
         1. Transitional link between the hindfoot and forefoot
2. Mid Foot
   1. Bones
      1. Navicular
         1. The navicular has poor blood supply and the main attachment for posterior tibial tendon on medial side.
      2. Cuboid
      3. Three Cuneforms (Medial, Intermedius, Lateral).
         1. These are important for stability along with the plantar and dorsal ligaments.
   2. Joints
      1. Five Tarsal-metatarsal joints, also known as the Lisfranc joint.
   3. Ligaments, muscles and tendons
      1. Plantar fascia ligament
         1. This ligament is responsible for forming arches of feet and shock absorber when dancing.
3. Forefoot
   1. Bones
      1. 14 Phalanges
      2. 5 Metatarsals
         1. The heads are the main weightbearing surface in the following ballet positions: Releve, quarter pointe, demi-pointe, and three quarter pointe.
      3. 2 Sesmoid bones
         1. These are located inside Flexor Hallucis Brevis tendon and allows toe to move up and down
   2. Joints
      1. Metatarsophalangeal joints
   3. Ligaments, muscles and tendons
      1. 1st metatarsal bone is the location for the attachment of several tendons and is important for it's role in propulsion and weight bearing

Ligaments of the Foot and Ankle

1. Medial Ligaments
   1. Deltoid ligament is fan shaped comprising 4 ligament and resists eversion:
      1. ATTL (deep component)
      2. CTL
      3. TNL
      4. PTTL (deep component)
   2. Expansion of joint capsule
      1. Spring ligament: Cradles and supports the talar head
      2. Lisfranc ligaments: Series of ligaments that stabilize tarsometatarsal joints and provide stability to the arch of the foot. The Plantar ligament is stronger than the dorsal ligament.
      3. Inter-metatarsal ligament: This is found between the tarsal bones and keep the metatarsals moving in sync. If the nerve running between these joints gets irritated, this could result in a Morton's neuroma.
         

         Pointe with Good Alignment
2. Lateral Ligaments
   1. Commonly injured side
   2. ATFL (tightens in PF)(weakest concluded by many authors)
   3. CFL  (Tightens in DF)
   4. Contribute to ankle stability
      1. PTFL
      2. AITFL
      3. PITFL
   5. Russel et al, 2008
   6. Demi –plié (DF) - ATFL will relax and CFL will be under tension
   7. Opposite is expected when en pointe (PF) although no studies have been done to examine extreme position en pointe
   8. Clear- strain in ATFL increases with increasing PF and is further accentuated during compressive loading through the ankle
   9. Maximum PF en pointe places ATFL parallel to fibula, thus functioning as a primary stabilizer of lateral ankle
   10. This places ATFL at particular risk – weakest and at its longest at maximal tension force

Syndesmosis

Ligament formed by

1. AITFL
2. Interosseus membrane
3. PITFL
4. Transverse ligament
5. Interosseus ligament

Their function is to hold the tibia and fibula together at the appropriate distance and form a mortise where talus sits.

Muscles of the Foot and Ankle

1. Extrinsic Foot Muscles

These muscles have contractile portions that lie outside the ankle, in the leg, and the tendons of those muscles insert onto the bones of the foot in such a way that ankle motion occurs when the muscles contract. There are four 4 compartments, separated by fascia. The Superficial Posterior compartment, Deep Posterior Compartment and the Lateral Compartment are all Plantarflexors and the Anterior compartment are the Dorsiflexors.

1. Superficial Posterior compartment (Plantarflexors)
   1. Gastrocnemuis (TA)
   2. Soleus (TA)
   3. Plantaris
2. Deep Posterior Compartment (Plantarflexors)
   1. FHL (inversion) (plantar surface of 1 toe)
   2. FDL (inversion) (plantar surface 2-5 toes)
   3. Tibialis Posterior (inversion) (navicular, medial cuneiform, 2-4 toes, other cuneiforms, cuboid)
3. Lateral Compartment (Plantarflexors)
   1. PL (eversion, PF first metatarsal) (medial cuneiform and 1 toe)
   2. PB (eversion)  (5 toe)
4. Anterior compartment (Dorsiflexors)
   1. Tibialis anterior (inversion) (1 toe, medial cuneiform
   2. EHL (inversion)
   3. EDL
   4. PT (eversion)

Muscle	Origin	Insertion	Action	Innervation	Arterial Supply
Flexor Digitorum Longus	Posterior surface of tibia distal to popliteal line	Splits into four slips after passing through medial intermuscular septum of plantar surface of foot; these slips then insert on plantar surface of bases of 2nd - 5th distal phalanges	Flexes toes 2 - 5; also helps in plantar flexion of ankle	Tibial nerve (S2, S3) (S2, S3)	Muscular branch of posterior tibial artery
Flexor Hallucis Longus	Inferior 2/3 of posterior surface of fibula, lower part of interosseous membrane	Plantar surface of base of distal phalanx of great toe	Flexes great toe, helps to supinate ankle, and is a very weak plantar flexor of ankle	Tibial nerve (S2, S3) (S2, S3)	Muscular branch of peroneal and posterior tibial artery
Tibialis Posterior	Posterior aspect of interosseous membrane, superior 2/3 of medial posterior surface of fibula, superior aspect of posterior surface of tibia, and from intermuscular septum between muscles of posterior compartment and deep transverse septum	Splits into two slips after passing inferior to plantar calcaneonavicular ligament; superficial slip inserts on the tuberosity of the navicular bone and sometimes medial cuneiform; deeper slip divides again into slips inserting on plantar surfaces of metatarsals 2 - 4 and second cuneiform	Principal invertor of foot; also adducts foot, plantar flexes ankle, and helps to supinate the foot	Tibial nerve (L4, L5) (L4, L5)	Muscular branches of sural, peroneal and posterior tibial arteries
Peroneus Longus	Head of fibula, upper 1/2 - 2/3 of lateral fibular shaft surface; also anterior and posterior intermuscular septa of leg	Plantar posterolateral aspect of medial cuneiform and lateral side of 1st metatarsal base	Everts foot and plantar flexes ankle; also helps to support the transverse arch of the foot	Superficial peroneal nerve (L5, S1, S2); may also receive additional innervation from common or deep peroneal nerves (L5, S1, S2)	Anterior tibial and peroneal arteries

2. Intrinsic Foot Muscles

These muscles all originate and insert within the foot. They are known to move the toes and stabilize the foot. Dancers refer to these muscles as the “core” muscles of the foot

19 muscles (2 on dorsum – EHB, EDB)

3 largest muscles are Abductor Hallucis, FDB, Quadratus Plantae

Provide support and stability of the arch

Most conditions require strength and control of these muscles

Dancer needs to learn to work with “straight” toes – provides counter stability to MT when pointing

Four Muscle Layers of the Plantar Foot

First LAyer

Layer One

Most superficial of all the layers

1. Muscles
   1. Abductor hallucis        
   2. Flexor digitorum brevis (FDB)        
   3. Abductor digiti minimi

Second Layer

Layer Two

1. Muscles
   • quadratus plantae        
   • lumbrical muscles        
2. Tendons
   • flexor digitorum longus (FDL)        
   • flexor hallucis longus (FHL)        
3. Neurovascular structures
   • medial and lateral plantar arteries

Layer Three

1. 

   Third Layer
   Muscles
   1. Flexor hallucis brevis        
   2. Oblique and transverse heads of the adductor hallucis        
   3. Flexor digiti minimi brevis

Fourth Layer

Layer Four

Deepest layer and both tendons travel to their insertion point via fibro-osseus tunnels

1. Muscles
   1. Dorsal interosseous        
   2. Plantar interosseus        
2. Tendons
   1. Peroneus longus
   2. Tibialis posterior        

Plantar fascia

• Strong fibrous tissue
• Originates deep within the plantar surface of the calcaneus and inserts on the base of each of the toes
• Toe DF= tightens fascia, supports arch
• Windlass mechanism

Arches

What makes up the arches of the foot?

Arches of the foot

Purpose:

1. Spring
2. Weight bearing
3. Shock absorption
4. Provides flexibility to the foot to facilitate function

1. Medial longitudinal arch

Highest arch

1. Bone
   

   Medial arch of the foot
   1. Shape of bones
   2. First 3 metatarsals
   3. 3 cuneiforms
   4. Navicular
   5. Talus
   6. calcaneus
2. Ligament
   1. Spring ligament
   2. Deltoid ligament
   3. Interosseus ligament
   4. Plantar aponeurosis
   5. Long and short plantar ligaments
3. Muscle
   1. Tib posterior
   2. Tib anterior
   3. FHL
   4. FDL
   5. Short muscles of the big toe

2. Lateral longitudinal arch

Lateral Arch of the foot

Lies on ground in standing position

1. Bone
   1. Shape of the bones
   2. Calcaneus
   3. Cuboid
   4. 4th and 5th metatarsals
2. Ligament
   1. long and short plantar ligaments
   2. Interosseus ligament
   3. Plantar aponeurosis
3. Muscle
   1. Peroneus longus and brevis
   2. Flexor digitorum longus
   3. Short muscles of the little toe

3. Transverse Arch

Demi Pointe with weight bearing surface on the Transverse Arch

1. Bone
   1. Wedge shape of the lateral and intermediate cuniform
   2. Metatarsal bases
   3. Cuboid
   4. 3 cuneiform
2. Ligament
   1. Deep transverse ligament
   2. Dorsal and plantar ligament
3. Muscle
   1. Peroneus longus and brevis
   2. Transverse head of adductor hallucis
   3. Slips of tibial posterior