The Ankle and Foot

STRUCTURE AND FUNCTIONOF THE ANKLE AND FOOT

Bones of the ankle

• The distal tibia and fibula

• 7 tarsal

• 5 metatarsals

• 14 phalanges

Ankle (Talocrural) Joint

Characteristics.

• The ankle (talocrural) joint is a synovial hinge joint formed by the mortise (distal end of the tibia and tibial and fibular malleoli) and trochlea (dome) of the talus

STRUCTURAL RELATIONSHIPSAND MOTIONS

Anatomical Characteristics

LegThe tibia and fibula make up the

leg. These two bones are bound

together by an interosseous

membrane along the shafts of

the bones,

STRUCTURAL RELATIONSHIPSAND MOTIONS

FootHindfoot

The talus and calcaneus make up the posterior segment.

STRUCTURAL RELATIONSHIPSAND MOTIONS

FootMidfoot.

The navicular, cuboid, and three cuneiforms make up the middle segment

STRUCTURAL RELATIONSHIPSAND MOTIONS

FootForefoot.

Five metatarsals and 14 phalanges make

up the anterior segment. Each toe has three phalanges except forth large toe, which has two.

Motions of the Foot and Ankle Defined

Primary Plane Motions

Sagittal plane motion around a frontal

Frontal plane motion around a sagittal Plane.

Inversion is inward turning of the foot and eversion is

Outward turning

Triplanar Motions

• Pronation

Pronation is a combination of dorsiflexion,eversion, and abduction.

Triplanar Motions

• Supination.

• Supination is a combination of plantarflexion,inversion, and adduction.

FUNCTIONOFTHEANKLE AND FOOT

Structural Relationships

Arches

• Primary support of the arches comes from the spring ligament

• In the normal static foot, muscles do little to support the arches

FUNCTIONOFTHEANKLE AND FOOT

Structural Relationships

Effect on posture.

• During standing if one foot/ ankle complex is more pronated than the other, the overall effect is a

Frontal plane asymmetry with a “short leg” on that side

FUNCTIONOFTHEANKLE AND FOOT

Structural RelationshipsAbnormal foot postures• A varus deforimity of the calcaneus may compensate by standing with a pronated

(or everted) calcaneus posture• Pes cavus and supinated foot describe a high-arched foot

Muscle Function in the Ankle and Foot

Plantarflexors. PrimaryGastrocnemiusSoleus SecondryTibialis posteriorThe flexor hallucis longusFlexor digitorum longus The peroneus longus

Muscle Function in the Ankle and Foot

Dorsiflexors

• Tibialis anterior

• The extensor hallucis longus and extensor digitorum longus

• Peroneus tertius

THE ANKLE/FOOTCOMPLEXAND GAIT

• During the normal gait cycle, the ankle goes through a ROM of 32deg to 35deg

REFERRED PAINAND NERVE INJURY

Major Nerves Subject to Pressure and Trauma

• Common peroneal nerve.

• Posterior tibial nerve

• Plantar and calcaneal nerves

Common Sources of SegmentalSensory Reference in the Foot