CHAPTER 8:PART 1
THE LOWER EXTREMITY:
KINESIOLOGY
Scientific
Basis of Human
Motion,
12 edition
KNEE,
ANKLE,
AND
FOOT
th
Hamilton, Weimar & Luttgens
Presentation Created by
TK Koesterer, Ph.D., ATC
Humboldt State University
Revised by Hamilton & Weimar
McGraw-Hill/Irwin
Copyright © 2012 by The McGraw-Hill Companies, Inc. All rights reserved.
OBJECTIVES
1. Name, locate, & describe the structure & ligamentous
reinforcements of the joints of the knee, ankle, and
foot.
2. Name & demonstrate movements possible.
3. Name & locate muscles & muscle groups, and name
their primary actions.
4. Analyze the fundamental movements with respect to
joint & muscle actions.
5. Describe common athletic injuries.
8-2
THE KNEE JOINT: STRUCTURE



Hinge joint.
Two condyles of femur
articulate with tibial plateaus.
Patella articulates with
patellar surface of femur.
Fig 8.2
Menisci
 Circular rims of fibrocartilage.
 Lateral –an incomplete circle.
 Medial – “C” shaped.
 Thick peripheral borders,
tapering to a thin inner edge.
Fig 8.4
8-3
LIGAMENTS OF THE KNEE
Lateral
Lateral
Medial
Fig 8.3
8-4
LIGAMENTS OF THE KNEE
Lateral
Medial
Fig 8.6
Fig 8.5
8-5
MUSCLES OF THE KNEE JOINT
Anterior
Quadriceps Group
Rectus femoris
Vastus intermedius
Vastus lateralis
Vastus medialis
Posterior
Hamstring Group
Biceps femoris
Semimembranosus
Semitendinosus
Sartorius
Gracilis
Popliteus
Gastrocnemius
8-6
MUSCLES OF THE KNEE JOINT
Rectus Femoris
Function:
 Powerful knee extensor.
Sartorius
Function:
 Flexion and internal
rotation in non-weight
bearing.
Fig 8.7
8-7
MUSCLES OF THE KNEE JOINT
Vastus intermedius
Vastus lateralis
Vastus medialis
Function:
 Powerful knee
extensors.
Fig 8.8
8-8
MUSCLES OF THE KNEE JOINT
Biceps femoris
Function:
• Flexes knee & external
rotation of tibia in non-weight
bearing.
Semimembranosus
Semitendinosus
Function:
• Flexion and internal rotation
in non-weight bearing.
Fig 8.10
8-9
MUSCLES OF THE KNEE JOINT
Gracilis
Function:
• Flexes knee.
• Slightly active in internal
rotation of tibia when knee is
flexed.
Popliteus
Function:
• Helps flex knee (unlocks).
• Internally rotates tibia.
Fig 8.11
8-10
MUSCLES OF THE KNEE JOINT
Gastrocnemius
Function:
• Helps flex knee.
• In weight bearing can
help maintain knee
extension.
Fig 8.23
8-11
MUSCULAR ANALYSIS OF FUNDAMENTAL
MOVEMENTS OF THE LEG AT THE KNEE JOINT
Flexion: Hamstrings, sartorius, gracilis
 Extension: Quadriceps
 External Rotation: Biceps femoris

 Can
only occur when knee is flexed & non-weight
bearing.

Internal Rotation: Semimembranosus,
semitendinosus, popliteus
 Can
only occur when knee is flexed & non-weight
bearing.
8-12
COMMON INJURIES OF THE LEG, KNEE AND
ANKLE
The Leg: Tibial Stress Injuries






Often called “shin splints”.
An overuse injury.
Repeated microtears where tibialis posterior or
anterior attaches to tibia, inflammation.
Sprains in interosseous membrane.
Tenderness & pain on medial surface of tibia.
Rest, softer surface and supporting the arch are
best treatment.
8-13
COMMON INJURIES OF THE LEG, KNEE AND
ANKLE
The Leg: Fracture
 Most common among the young.
 Most common to lower 2/3 of fibula.
 May result in instability of ankle joint.
 Severity based on bone displacement:
 More displaced - more severe.
The Leg: Shin Contusions
 Common based on exposed nature of tibia.
 Usually from a direct blow.
 May damage periosteum.
 Shin guards are recommended in activities in which leg
impacts are common.
8-14
COMMON INJURIES OF THE LEG, KNEE AND
ANKLE
The Knee: Collateral Ligament Sprain

Direct blow to either side of knee.


Majority are blows from lateral side causing medial collateral
ligament damage.
Depending on amount of force the following structures could be
injured:



Medial collateral ligament
Medial meniscus
Anterior cruciate ligament
The Knee: Chondromalacia



Degeneration of cartilage on articulating surface of patella.
Pain, on movement, swelling, grating sensation.
Treatment through evaluation of lower body biomechanics,
rehabilitative exercises, limiting activities.
8-15
COMMON INJURIES OF THE LEG, KNEE AND
ANKLE
The Knee: Osgood Schlatter Disease
Due to repeated overuse of knee
extensors.
 Tearing or avulsion of epiphysis of tibial
tuberosity.
 Swelling, pain on activity & kneeling.
 Treat with rest, ice, rehabilitative
exercises.

8-16
THE ANKLE AND FOOT:
The foot provides for support and propulsion.
 Movements within the foot occur primarily at
the subtalar and midtarsal joints.
 The ankle serves to unite the foot and the
leg.

8-17
STRUCTURE OF THE ANKLE
Hinge joint
 Articulation of talus
with malleoli of
tibia & fibula.
 Bound together by
ligaments.

Tibia
Fibula
Talus
Sustentaculum
tali
Calcaneous
Fig 8.12
8-18
LIGAMENTOUS REINFORCEMENT
Lateral side
 Anterior talofibular
 Calcaneofibular
 Posterior talofibular
Medial side
 Deltoid
 Calcaneotibial
 Anterior talotibial
 Tibionavicular
 Posterior talotibial
 Plantar calcaneonavicular
Fig 8.14
Deltoid
a. Calcaneotibial
d. Posterior
talotibial
b. Anterior talotibial
c. Tibionavicular
Fig 8.13
Plantar calcaneonavicular
8-19
STRUCTURE OF THE FOOT

An elastic arched
structure.
 Talus
is the keystone.
 Comprised of two
arches:
 Longitudinal
 Transverse
Fig 8.15
8-20
STRUCTURE OF THE FOOT

Longitudinal arch:



Heel to heads of five
metatarsals.
Supported by the plantar
fascia.
Transverse arch:


Side-to-side concavity.
Anterior tarsal bones &
metatarsals.
Fig 8.16
8-21
SUBTALAR JOINT
Joint between underside of talus and upper
& anterior aspects of calcaneus.
 Plantar calcaneonavicular “spring ligament”
helps support talus.

Fig 8.17b
8-22
FOOT JOINTS
Midtarsal Joint (Chopart’s Joint): Consists of two
articulations:


Calcaneocuboid: Nonaxial – permits only gliding.
Talonavicular: Modified ball-and-socket – permits restricted
motion.
Tarsometatarsal Joints: Movements are gliding.
Intermetatarsal Joints: spreading or flattening.
Metatarsophalangeal Joints: Modified condyloid joints.
Interphalangeal Joints: Hinge joints.
8-23
MOVEMENTS OF FOOT AT THE ANKLE, TARSAL, &
TOE JOINTS
Fig 8.20
8-24
MUSCLES OF THE ANKLE & FOOT
Location:
 22 muscle of the ankle & foot are intrinsic.
 11 muscles are extrinsic.
8-25
MUSCLES OF THE ANKLE & FOOT
Tibialis Anterior
Function: dorsiflexes ankle &
supinates foot.
Peroneus Brevis
Function: plantarflexes, everts.
Extensor Hallucis Longus
Extensor Hallucis Brevis
Function: extends great toe.
Extensor Digitorum Brevis
Function: extends toes.
Fig 8.21a
8-26
MUSCLES OF THE ANKLE & FOOT
Extensor Digitorum
Longus
Function: extends toes.
Peroneus Longus
plantarflexes,
everts, abducts.
Peroneus Tertius
Function: dorsiflexes &
pronates.
Fig 8.22
8-27
MUSCLES OF THE ANKLE & FOOT
Gastrocnemius
Function: powerful plantar flexor.
 Fast twitch.
 Allows one to rise on toes, lift
body weight.
 Advantageous leverage.
Fig 8.23
8-28
MUSCLES OF THE ANKLE & FOOT
Soleus
Function: Strong ankle plantar flexor.
 Slow twitch.
 Postural, static plantar flexion.
Fig 8.24
8-29
MUSCLES OF THE ANKLE & FOOT
Tibialis Posterior
Function: plantar flexes tarsal
joints, supination when foot is
plantar flexed.
 Helps holds up longitudinal
arch.
Fig 8.25
8-30
MUSCLES OF THE ANKLE & FOOT
Flexor Digitorum Longus
Function: Flexes toes, plantar
flexes, helps inversion.
Flexor Hallucis Longus
Function: flexes great toe, plantar
flexes, helps inversion.
Fig 8.26
8-31
INTRINSIC MUSCLES OF THE FOOT
Fig 8.27 & 8.28
8-32
INTRINSIC MUSCLES OF THE FOOT
Fig 8.29 & 8.30
8-33
MUSCULAR ANALYSIS OF FUNDAMENTAL
MOVEMENTS: ANKLE
Dorsiflexion: tibialis anterior, peroneus tertius,
extensor digitorum longus, extensor hallucis
longus.
 Plantar flexion: gastrocnemius, soleus,
peroneus.

 Possible
help from tibialis posterior, peroneus
brevis, flexor digitorum longus, flexor hallucis.
8-34
MUSCULAR ANALYSIS OF FUNDAMENTAL
MOVEMENTS: TARSAL JOINTS
Dorsiflexion: same as ankle.
 Plantar flexion: tibialis posterior, flexor
digitorum longus, flexor hallucis longus,
peroneus longus.
 Supination: tibialis anterior (when foot is
dorsiflexed) & tibialis posterior (when foot is
plantar flexed).
 Pronation: peroneus longus, brevis, & tertius.

8-35
MUSCULAR ANALYSIS OF FUNDAMENTAL
MOVEMENTS: TOES
Flexion: flexor digitorum longus and flexor
hallucis longus.
 Extension: extensor digitorum longus and
extensor hallucis longus.

8-36
COMMON INJURIES OF THE LEG, KNEE AND
ANKLE
The Ankle: Strain
Due to impact that forces ankle beyond
normal range.
 Results in tearing at myotendinous
junction.
 May cause pain, weakness, possible
deformity. Potentially very debilitating.

8-37
COMMON INJURIES OF THE LEG, KNEE AND
ANKLE
The Ankle: Sprains
Usually associated with forceful inversion
of the foot.
 In this case the lateral ligaments
stretched or torn, or may rupture.
 Results in pain, swelling, disability.

8-38
COMMON INJURIES OF THE LEG, KNEE AND
ANKLE
The Ankle: Fracture
Same causes as ankle sprains.
 The majority occur to malleoli.
 More serious fractures sometimes
dislocate.

8-39
COMMON INJURIES OF THE LEG, KNEE AND
ANKLE
The Foot: Plantar Fasciitis
Pain and tenderness along the sole of the
foot.
 May be due to inflammation, micro tears, or
rupture of the plantar fascia.
 Is generally an overuse injury; lack of
flexibility may be contributory.
 Stretching has been shown to be helpful.

8-40