Anatomy of Skeletal Elements

The Musculoskeletal system

• 206 bones• grouped into the axial and appendicular

skeletons

• 650 muscles– approximately 40% of your body weight– also divided into an axial and an appendicular

division

Classification of Bones• 6 types - based on anatomical

classification– Long bones = greater length than width

– Short bones = cube-shaped, spongy bone except at surface

– Flat bones = two parallel plates of compact bone sandwiching spongy bone layer

– Irregular bones = cannot be grouped

– Sesamoid bones = develop in tendons where there is considerable friction, tension and stress

– Sutural bones = located within joints between cranial bones

Bone Markings (surface features)• Used to identify specific

elevations, depressions, and openings of bones

• Bone markings provide distinct and characteristic landmarks for orientation and identification of bones and associated structures.

Bony Processes

• Depressions and openings– Fissure – narrow slit– Foramen – hole for nerves, blood vessels– Fossa – cuplike depression– Sulcus – furrow on a bone surface, contains a nerve or blood vessel– Meatus – tubelike opening

• Processes – projection or outgrowth on bone for attachment– Condyle – smoothened process at end of bone, forms a joint– Facet – smooth flat surface, forms a joint– Head – rounded condyle on a neck, forms a joint– Crest – prominent ridge or projection, for attachment of connective tissues– Epicondyle – projection above a condyle, for attachment of connective tissues– Line – long, narrow ridge (less prominent than a crest), for attachment of

connective tissues– Spinous process – sharp, slender projection, for attachment of connective tissues– Trochanter – process of the femur, for attachment of connective tissues– Tubercle – process of the humerus, for attachment of connective tissues– Tuberosity – roughening on a bone surface, for attachment of connective tissues

Skeletal system includes

• Axial division– Skull and associated bones

• Auditory ossicles

• Hyoid bones

– Vertebral column– Thoracic cage

• Ribs & sternum

• Appendicular division-Pectoral girdle-Pelvic girdle

THE SKELETAL SYSTEM: AXIAL DIVISION

Part A

The Axial Skeleton• Axial division

– Skull and associated bones

• Auditory ossicles

• Hyoid bone

– Vertebral column

– Thoracic cage• Ribs & Sternum

The Skull and Associated Bones

The Adult Skull• skull = 22 bones

• cranium = 8 bones: 1 frontal, 1 occipital, 2 temporals, 2 parietals, 1 sphenoid and 1 ethmoid

• facial bones = 14 bones: 2 nasals, 2 maxillae, 2 zygomatics ,1 mandible, 2 lacrimals, 2 palatines, 2 inferior nasal conchae, 1 vomer

• mandible and auditory ossicles are the only movable skull bones

The Adult Skull

• skull is made up of several cavities– 1. cranial cavity– 2. nasal cavity– 3. the orbits– 4. paranasal sinuses

• skull contains many holes for the passage of nerves and vessels = foramen/foramina

• cranial bones also attach to membranes called meninges• outer surface provides large areas for muscle attachment that move

the head or provide facial expressions

Sutures

• Immovable joints • form boundaries between skull bones• four main sutures

– Coronal

– Sagittal

– Lambdoid

– Squamous

– PLUS lots of smaller sutures• e.g. Frontonasal

• e.g.Temperozygomatic

• part of the base of the skull

• surrounds the foramen magnum

• forms part of the jugular foramen

• hypoglossal foramen found under the occipital condyles

Mastoid notch

Occipital Bone

•Part of the superior and lateral surfaces of the cranium•united by a sagittal suture•connects to frontal bone by coronal suture•connects to occipital bone by lambdoid suture

Parietal Bone

•forms wall of jugular foramen•three portions: squamous, petrous and tympanic•petrous part houses tympanic membrane and middle and inner ears•auditory ossicles of middle ear transmit sound to inner ear

Temporal Bone

Petrousportion

Tympanicportion

Temporal Bone

ArticularTubercle

Squamousportion

Petrousportion

Tympanicportion

Frontal process of zygomatic bone

Maxillary process of zygomatic bone

Temporal surface of greater wing of sphenoid

Lacrimal bone

glabella Internasal suture

Zygomatic processof maxilla

Frontal process of maxilla

Supraorbital ridgeor margin

Frontal Bone

– Forms the forehead & roof of the orbit

glabella

• Contributes to floor of cranium

• Bridges cranial and facial bones

• Optic canal allows passage of optic nerve

• Pterygoid processes sites of muscle attachment

Sphenoid Bone

• Irregularly shaped bone

• forms part of orbit & forms roof of nasal cavity

• Cribriform plate with olfactory foramina for olfactory nerves

• Perpendicular plate forms part of nasal septum

Ethmoid Bone

Facial Bones: Maxilla• Paired bone

– Largest of the facial bones

– Forms upper jaw

• entire lower jaw

• articulates with temporal bone at the Temporomandibular joint

• moveable part of skull

Facial Bones: Mandible

• Nasal bones – Paired bones

– Articulate with frontal bone

– Extend to superior border of external nares

• Vomer– Forms inferior (bottom) portion of

nasal septum

– Articulates with maxillae and palatine bones

Facial bones

Nasal bones

• Inferior nasal concha– Located on each side of nasal septum

– Increase epithelial surface

– Create turbulence in inspired air

• Zygomatic bone– Temporal process articulates with zygomatic process of temporal bone

– Forms zygomatic arch

Facial bones

• Palatine bones– Small

– L-shaped

– Form posterior portion of hard palate

– Contribute to floor of orbit

•Lacrimal bones–Smallest bones in skull

–Delivers tears to nasal cavity via nasolacrimal canal

Facial bones

The Orbit• Orbital complex

– Bony recess that holds the eye– Seven bones

• Frontal bone

• Lacrimal bone

• Palatine bone

• Zygomatic bone

• Ethmoid

• Sphenoid

• Maxilla

Skull: Inferior View

Petrousportion

Condylar foramenmay be present

Condylar fossa

Basilar Portion

Figure 6.4 Sectional Anatomy of the Skull, Part I

Lesser wing of sphenoid

Skull: Interior View

Cerebral surface ofGreater wing of sphenoid

ForamenRotundum

Hypophyseal fossa

Dorsum sella

Tuberculum sellae SellaTurcica

Cranial Fossae

• Depressions in cranial floor

• for the lobes of the brain

• Anterior cranial fossa – Frontal bone, ethmoid,

lesser wings of sphenoid

• Middle cranial fossa– Sphenoid, temporal

bones, parietal bones

• Posterior cranial fossa– Occipital bone, temporal

bones, parietal bones

Skull: Sagittal View

Skull: Sagittal View

• Bones and cartilage that enclose the nasal cavity

• lined with a nasal mucosa• associated with the 4

paranasal sinuses– hollow airways

– lined with mucosa – like nasal mucosa

– found in the frontal bones, sphenoid, ethmoid and maxillae

The Nasal Complex

The Paranasal Sinuses

Infant Skull: The Fontanels• the flat bones in the infant

skull are separated by fontanels

• fibrous connections between skull bones

• permit infant skulls to pass through birth canal

• permit the skulls of infants and children to continue growing

• will be replaced by sutures in the adult skull

The Hyoid Bone• Consists of a body, greater horns and lesser horns• Base for muscles of the tongue and larynx

Adult Vertebral Column• strong, flexible rod

– average male = 71 cm (28 inches)

– average female – 61 cm (24 inches)

• capable of moving– anteriorly

– posteriorly

– laterally

– also rotation

• supports the head

• encloses and protects the spinal cord

• allows for the exit of 31 pairs of spinal nerves – through intervertebral foramina

Adult Vertebral Column• 26 vertebrae

– 24 individual vertebrae– Sacrum– Coccyx

• Seven cervical vertebrae

• Twelve thoracic vertebrae

• Five lumbar vertebrae

• Sacrum – 5 fused vertebrae

• Coccyx – 4 fused vertebrae

Adult Vertebral Column• vertebrae separated by

intervertebral discs– discs of fibrocartilage made up of an

outer ring and a softer inner region

– found between C1 and C2 and all the way down to between L5 and the sacrum

– form the joints of the vertebral column

Adult Vertebral Column• absorb shock – flatten,

broaden and bulge outward• weakening in the outer ring

can allow the herniation of the inner material

Spinal Curvature• Four curvatures: increase the strength of the column

– Thoracic (primary) – forms fetally and retain the curve of the fetus

– Sacral (primary) – forms fetally and retain the curve of the fetus

– Cervical (secondary) – forms when the baby holds its head erect

– Lumbar (secondary) – forms upon walking

• Every vertebrae has the following:– 1. body – weight bearing part of the

vertebra• separated by the discs

– 2. vertebral arch – surrounds the spinal cord

• surrounds a hole called a vertebral foramen

– 3. processes – seven of them• 1. Spinous (1) – muscle attachment

• 2. Transverse (2) – muscle attachment

• 3. Superior articular (2) – forms joint with upper vertebra

• 4. Inferior articular (2) – forms joint with lower vertebra

Vertebrae

Vertebrae

Cervical Vertebra

• cervical vertebrae = transverse foramina in the transverse processes

• bifid spinous process

• 1st two cervical vertebrae (atlas and axis) look different but have all aspects of a vertebrae

Thoracic Vertebrae Lumbar

Vertebrae

Fused Vertebrae: The sacrum & coccyx

• Sacrum - Union of 5 vertebrae (S1 - S5) – completely fused by age 30– median sacral crest = fused spinous processes– sacral ala = fused transverse processes– sacral canal ends at sacral hiatus

• Coccyx = Union of 4 vertebrae (Co1 - Co4) – completely fused by age 30

Rib Cage• 12 pairs of ribs

• vertebral end for articulation with the facets of the 12 thoracic vertebrae – both body and the transverse process

• sternal end for articulation with the sternum

Rib Cage

-three kinds of ribs:1. True – separate & direct connection to the sternum via costal cartilage2. False – no direct connection to the sternum – joined via a composite piece of costal cartilage3. Floating – no connection to the sternum

Sternum

• comprised of the:• 1. Manubrium – with

two clavicular notches and a jugular notch

• 2. Body – connects to manubrium via a sternal angle

• 3. Xiphoid process

Sternum & Rib Cage• several muscles and muscle groups either originate from the sternum

and/or ribcage (or costal cartilages) or insert onto these structures

– sternum:• sternocleidomastoid• sternohyoid & sternothryoid – depresses hyoid bone and larynx

– ribcage:• intercostals – external and internal• serratus anterior & posterior• numerous muscles of the vertebral column• pectoralis major & minor• 4 muscles of the abdominal wall

THE SKELETAL SYSTEM: APPENDICULAR DIVISION

Part A

Appendicular Skeleton• Bones of upper and lower limbs• Pectoral and pelvic girdles

– Connect limbs to trunk

Shoulder Girdle• Includes

– Scapula (shoulder blade)– Clavicle (collarbone)

• Squares shoulders

• Helps move the upper limb

• Provides a base for muscle attachment

Clavicle• S-shaped bone

• Connects manubrium of sternum to the acromion process of scapula

• Only direct connection between pectoral girdle and axial skeleton

The Scapula

• Medial or vertebral border is the insertion point for the rhomboids, levator scapulae & serratus anterior

• Two processes attach to ligaments and tendons– Coracoid process – e.g insertion for pectoralis minor, origin of biceps

– Acromion process – e.g. origin of the deltoid• continues on to become the scapular spine

• Articulates at the round head of the humerus to form the glenohumoral joint

• Articulates with clavicle at the acromioclavicular joint

Figure 7.5a, b The Scapula

The Humerus• articulates with glenoid cavity of

scapula

• possesses an anatomical neck for capsule attachment and a surgical neck

• trochlea and capitulum form joints with the ulna and radius = elbow joint

• numerous muscles insert at greater and lesser tubercle– greater tubercle – insertion of 3 rotator

cuff muscles + pectoralis major

– lesser tubercle – insertion for the other rotator cuff

• intertubercular groove – insertion for latissimus dorsi

• deltoid tuberosity

– insertion of deltoid muscle

The Radius and Ulna• Parallel bones of the forearm

• radial tuberosity – insertion point for the biceps brachii

• Olecranon process of ulna articulates with olecranon fossa of humerus

– olecranon process is a major point of muscle attachment for the triceps

• Coronoid fossa of humerus accommodates coronoid process of ulna

– insertion for the major forearm flexor = brachialis

Carpal Bones• 8 wrist bones

• Two rows, proximal and distal– scaphoid bone, lunate bone, triquetrum, pisiform

– trapezium, trapezoid bone, capitate bone, hamate bone

– scaphoid = most commonly injured carpal bone• fall on the outstretched hand – fracture into two separate pieces (tears blood vessels)

“Some lovers try positions that they can’t handle”

Metacarpal Bones

• Articulate with distal carpals

• Distally articulate with phalanges– Fingers have three

phalanges– Pollex/thumb has two

phalanges

The Pelvic Girdle

• ossum coxa– Ilium– Ischium– Pubis

• the pelvic girdle consists of the two ossa coxae.

• union between pelvis and sacrum = sacroiliac joint

The Pelvic Girdle• Ilium

– Largest hip bone

– accommodates the head of the femur

– Fused to ischium posteriorly

– Fused to pubis anteriorly via the superior ramus

• Pubis– “pubic bone”

– superior & inferior ramus• rami connect to the ilium and ischium

• surrounds the obturator foramen

– pubic symphysis is pad of fibrocartilage between 2 pubic bones

• known as an amphithrotic (slightly movable) joint

• Ischium– “sit bones”

– ischial spine & tuberosity• ischial tuberosity – site of origin

for hamstrings and adductor magnus

– lesser sciatic notch

– ramus unites with the pubis

– inferior pubic ramus for origin of iliacus (hip flexor), gracilis, adductor brevis and magnus (hip adductors)

– superior pubic ramus for origin of the hip adductor pectineus

– pubic crest/tubercle for origin of adductor longus

– iliac fossa for origin of iliacus– iliac crest for origin of gluteus maximus and

medius– anterior gluteal line for origin of gluteus medius– anterior superior iliac spine for origin of

sartorius– anterior inferior iliac spine for origin of rectus

femoris– greater sciatic notch for passage of sciatic nerve

Figure 7.12a-c Divisions of the Pelvis

Female vs. Male Pelvis

• Smoother

• Lighter

• Less prominent markings

• Enlarged pelvic outlet

• Less sacral curvature

• Wider more circular pelvic inlet

• Broader pubic angle

The Femur• Longest bone in body

– takes 4-5 months to completely replace

• Rounded head on an anatomical neck– fits into the acetabulum of the pelvis to

form the hip joint

• proximal trochanters for muscle attachment

• Distal medial and lateral condyles articulate with tibia – to form the knee joint– knee joint is a hinge joint capable of one

plane of motion

• Large tendon attachments to the trochanters and the linea aspera

• Linea aspera– roughened line on the back of the

femur

– origin for the hamstring biceps femoris (short head) & the knee extensor vastus medialis

– also the insertion point for adductor longus, brevis and magnus

• Greater and lesser trochanters

– greater trochanter – origin of vastus lateralis (knee extensor) & the insertion point for the hip abductors: gluteus medius and minimus and piriformis

– lesser trochanter – insertion for iliopsoas (hip flexor)

The Patella• Large sesmoid bone - forms within the tendon of the

quadriceps femoris.• Forms within tendon of quadriceps femoris muscle group • Patellar ligament attaches to tibial tuberosity

The Tibia• Largest bone of leg• Tibial tuberosity

– site of insertion for the quadriceps femoris

• Anterior margin– known as the “shin bone”

• Intercondylar eminence between the condyles– condyles of the tibia form the knee

joint with the condyles of the femur

• Medial malleolus– Medial support for talocrural joint

The Tibia & Fibula

The Tarsus• Seven tarsal bones

– calcaneus = heel• weight of body transferred

through this bone!

– talus – forms the ankle joint with the tibia and fibula

• ligaments from the two malleolus processes reinforce this joint

– navicular

– cuboid

– 3 cuneiform bones

• weight passing through the calcaneus then passes along to 5 metatarsal bones that form 2 arches:

-Longitudinal arch-Transverse arch

Joints

1. Cartilage: functions in support, attachment, protection-cells = chondrocytes-matrix = collagen II fibers embedded in a gel-like ground-substance-ground substance - water + proteoglycans-proteoglycans – core protein (aggrecan) + sugars (e.g. chondroitin sulfate, glucosamine)-in developing child - model for future bone

(endochondral bone formation)-avascular tissue - produces anti-angiogenic

chemicals (inhibits growth of blood vessels)-therefore diffusion is the main mode of

transport

Supportive Connective tissue: Cartilage

Proteoglycan

-3 types: 1) Hyaline - most common - “glass” - ends of bones, within joints (synovial, articular), - end of nose, supports respiratory passages

2. Elastic - flexible cartilage- external ears and parts of larynx

3. Fibrocartilage - very tough -> more collagen fibers- shock absorber

e.g. intervertebral discs of the knee

Classification of Joints

Articulation (A Joint)

• Wherever two bones interact• Function depends on structure• can classify according to:

A. structure – i.e. what they are made ofA. fibrous

B. cartilagenous

C. synovial

B. function - movement

– No movement = synarthrotic

– Slight movement = amphithrotic

– Extensive movement = diathrotic

•lack a synovial cavity•articulating surfaces are held very closely by fibrous connective tissue•three types:

1. Sutures: composed a thin layer of fibrous connective tissue-unites the bones of the skulle.g. coronal suture-interlocking edges of the suture gives them strength-immovable joint

2. Syndesmoses: greater distance between articular edges-more fibrous connective tissue-connective tissue arranged as a sheet (interosseous membrane) or bundle (ligament)-slightly movablee.g. tibiofibular ligament connecting the tibiofibular jointe.g. interosseous membranes between the radius and ulna, tibia and fibula

3. Gomphoses: cone shaped peg fits into a sockete.g articulations of the roots of the teeth with the jaw-held by the periodontal ligament-immovable

Fibrous Joints

•lacks a synovial cavity•allows little or no movement•articulating bones are connected by hyaline cartilage or fibrocartilage

1. Synchondroses: connecting material is hyaline cartilagee.g. epiphyseal/growth plate of a growing bone-immovable

2. Symphyses: ends of bones are covered with hyaline cartilage but are connected by a flat disc of fibrocartilage-all symphyses occur at the midline of the bodye.g. pubic symphysis - connects two ends of the pubis bonese.g. intervertebral joints between the bodies of 2 vertebrae

-slightly movable

Cartilagenous Joints

Synovial joints

•presence of a synovial cavity between the articulating bone surfaces•freely movable joints•lined with hyaline cartilage called articular cartilage•filled with a fluid called synovial fluid•surrounded by a fibrous capsule – inside is lined with a synovial membrane

•movement is along three possible axes:MonaxialBiaxialTriaxial or Multiaxial

Synovial Joints

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• Articular/Joint capsule encloses joint cavity– continuous with periosteum of the bones of the

joint

– lined by a synovial membrane that produces synovial fluid

• Synovial fluid = slippery fluid; feeds cartilages

• Articular cartilage = hyaline cartilage covering the joint surfaces

• Articular discs and menisci– found in the jaw, wrist, sternoclavicular and

knee joints

– absorbs shock, guides bone movements and distributes forces

• Tendon attaches muscle to bone

• Ligament attaches bone to bone

Synovial Joints: General Anatomy

Synovial joints

•synovial joint movement is along three possible axes:Monaxial or uniaxial – e.g. knee joint, elbow jointBiaxial – e.g interphalangeal jointTriaxial or Multiaxial – e.g. shoulder & hip joint

Synovial Joints

Synovial joints

•6 subtypes:1. planar/gliding2. hinge3. pivot4. condyloid5. saddle6. ball and socket

Synovial Joints Types

1. Planar/Gliding joints : articulating surfaces are flat or slightly curved

-permit side to side or back and forth gliding motions

-non-axial - no motions around an axis-some books say they are limited monaxial jointse.g. intercarpal joints of the wrist bonese.g. intertarsal joints of the ankle bones

2. Hinge joints: convex surface of one bone fits into a concave surface

-produces an angular, open and close movement-movement is in one plane of motion = monaxial

3. Pivot joints: rounded or pointed end of one bone fits into a ring of another-also monaxial-rotates around a longitudinal axise.g. atlas-axis joint - first 2 vertebrae

4. Condyloid joints: or ellipsoid joints-convex oval shaped projection of one bone fits into theoval-shaped depression of another bone-biaxial = two planes of motione.g. metacarpals and proximal phalangese.g. metatarsals and proximal phalangese.g. atlanto-occipital joint

5. Saddle joints: articular surface of one bone is saddle shaped-modified condyloid joint-biaxial – but more moveable than condyloid jointse.g. thumb metacarpal and trapezium carpal bone = trapeziometacarpal joint

6. Ball and socket joints: ball-like end of one bone fits into acuplike depression of another-mult-iaxial - several planes of motione.g. hip joint, shoulder joint

Three categories based on range of motion

• Synarthroses– Immovable joints

• Amphiarthroses– Slightly movable joints

• Diarthroses– Freely movable joints

Synarthroses• Bony edges may interlock

• Sutures– Between skull bones

• Gomphosis– Between teeth and jaw

• Synchondrosis– Epiphyseal plate

• Synostosis– Fused bones

Amphiarthroses• Limited movements

• Syndesmosis– Collagen fibers connect bones

• e.g. tibiofibular joint

• Symphysis– Bones are separated by cartilage pad

• e.g. pubic symphysis

Diarthroses (synovial joints)• Wide range of movement

• Bony surfaces covered by articular cartilage

• Lubricated by synovial fluid

• Enclosed with joint capsule

• Accessory structures– Menisci– Fat pads– Ligaments– Tendons– Bursae– Tendon sheaths

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• Degrees through which a joint can move

• Determined by– structure of the articular surfaces– strength and tautness of ligaments, tendons and

capsule• stretching of ligaments increases range of motion

• double-jointed people have long or slack ligaments

– action of the muscles and tendons• nervous system monitors joint position and muscle tone

Joints: Range of Motion

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• Abduction/Adduction• Flexion/Extension/Hyperextension

Joints: Range of Motion

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Movements of Head and Trunk

• Flexion, hyperextension and lateral flexion of vertebral column

Joints: Range of Motion

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• Movement on longitudinal axis– rotation of trunk,

thigh, head or arm

• Medial rotation turns the bone inwards

• Lateral rotation turns the bone outwards

Special movement terms: Rotation

• Medial and lateral rotation of the hand – called Pronation & Supination

Special movements of the hand: Pronation & Supination

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• Radial and ulnar flexion

• Abduction of fingers and thumb

• Opposition is movement of the thumb to approach or touch the fingertips

• Reposition is movement back to the anatomical position

Special movements of the hand

• Dorsiflexion is raising of the toes as when you swing the foot forward to take a step (heel strike)

• Plantarflexion is extension of the foot so that the toes point downward as in standing on tiptoe

• Inversion is a movement in which the soles are turned medially

• Eversion is a turning of the soles to face laterally

Special movement of the foot

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• Protraction & Retraction of mandible

• Lateral excursion = sideways movement

• Medial excursion = movement back to the midline– side-to-side grinding during chewing

Special movement of the Mandible: Protraction & Retraction

Representative Articulations

The Temporomandibular Joint• TMJ = mandibular fossa of temporal bone &

condylar processes of mandible

• Thick articular disc between the bones

• Supporting structures– Dense capsule

– Temporomandibular ligament

– Stylomandibular ligament

– Sphenomandibular ligament

• Loose hinge joint

Intervertebral Articulations• Articular processes of

adjacent vertebrae

• Symphyseal joints at bodies

• Ligaments bind vertebrae

• Permits flexion, extension, lateral flexion, rotation

The Sternoclavicular Joint• Gliding joint

• between the sternal end of clavicle and manubruim of sternum

•Articular disc•Supports include

-Anterior and posterior sternoclavicular ligaments-Interclavicular ligaments-Costoclavicular ligaments

The Shoulder Joint

• known as the glenohumoral joint– between the glenoid fossa

and head of humerus

• Loose shallow joint

• Greatest range of motionStrength and stability are

sacrificed for motion

• Supported by ligaments and muscles

• Many bursae to decrease friction between ligaments

The Elbow Joint• Hinge joint

• Flexion and extension

• Includes humeroulnar joint and humeroradial joint

• Supported by – Radial and ulnar collateral ligaments

– Annular ligaments

The joints & ligaments of the Wrist• Three joints

– Distal radioulnar joint• Pivot diarthrosis

• Pronation / supination

– Radiocarpal joint• Ellipsoidal articulation

• Flexion/extension

• Adduction/ abduction

• circumduction

– Intercarpal joints• Gliding joints

Joints of the Hand• Intercarpal joints

– Gliding

• Carpometacarpal joint of thumb– Saddle

• Carpometacarpal joints– Gliding

• Metacarpophalangeal joints– Ellipsoidal

• Interphalangeal joints– Hinge

The Hip Joint• Ball and socket diarthrosis

• Acetabulum of os coxae and head of femur

• Flexion / extension

• Adduction / abduction

• Circumduction

• Rotation

• Iliofemoral ligament

• Pubofemoral ligament

• Ischiofemoral ligament

• Transverse acetabular ligaments

• Ligament of femoral head

The Knee Joint• Complex hinge joint

• Resembles three separate joints– Medial condyles of femur and tibia

– Lateral condyles of femur and tibia

– Patella and patellar surface of femur

• Flexion / extension

• Limited rotation

• Support is not a single unified capsule– Not a single fluid cavity

• Fibrocartilage pads

• Medial and lateral menisci

• Fat pads

• Seven major ligaments bind knee joint– Popliteals

– Patellar

– Anterior and posterior cruciates

– Tibial and fibular collaterals

The Joints of the Ankle and Foot• Hinge joint

• Inferior surface of tibia, lateral malleolus of fibula, trochlea of talus– Primary joint is tibiotalar

• Stabilizing ligaments

• Dorsiflexion / plantar flexion

• Intertarsal joints– Gliding

• Tarsometatarsal joints– Gliding

• Metatarsophalangeal– Gliding

• Interphanageal– Hinge