The appendicular skeletonAppendicular skelton + skeletal muscles= movement

Bones of the appendicular skeleton2 pectoral girdlesClavicles, scapulae2 upper extremitiesPelvic girdleCoxae (hip bones)2 lower extremities

Some important external features of bonesProcesses where tendons and ligaments attachTrochanter, tuberosity- large and smallTubercle- roundedCrest- ridgeSpine- pointedProcesses formed at articulationsHead, condyle, facetDepressions and openingsFossa, sulcus, foramen, sinus

Pectoral girdle

The clavicleJoint between clavicle and sternum is only direct connection between axial skeleton, shoulder girdleEasily fractured

Scapula (shoulder blade)Glenoid cavity articulates with head of humerus to form shoulder jointAcromion forms tip of shoulder; articulates with claviceCoracoid process is an attachment site

Upper limbArm (humerus)Glenohumeral jointDistal end articulates with radius and ulnaForearmRadius (lateral), ulna (medial)Fibrous membrane connects the two

Wrist and hand8 carpals, 5 metacarpals, 14 phalangesCarpal tunnel formed by space between hamate and pisiform; scaphoid and trapeziumMedian nerve and flexor tendons pass through it

Pelvic girdle is much more massive than pectoral girdlePelvis: two coxae, sacrum, coccyxCoxa formed by ileum, ischium and pubisObturator foramen is largest in skeleton

Male and female pelvesFemale pelvis is lighter and shallowerwiderWider outlet

Pectoral vs pelvic girdlePectoral does not articulate directly with vertebraePectoral girdle provides more mobility than strengthPelvic girdle provides more strength than mobility

Lower limbFemur is longest, strongest, heaviest boneArticulates with pelvis at acetabulumArticulates with tibia and fibula at distal endTibia and fibula form lower legFibula is attachment site; does not bear weight or help form knee jointFibrous membrane between the two

Bones of ankle and footSeven tarsals; talus articulates with tibia and fibulaStanding, most weight is supported by calcaneusMuscles attached to calcaneus by Achilles tendonMetatarsal bones carry the rest

Arches of the footLongitudinal archBegins at calcaneus, extends to heads of metatarsalsTransverse archFormed by tarsals and bases of metatarsalsNormally ball of foot carries 40% of weight and heel 60%

Bone and joint disordersBone structure and remodeling is affected by:Age (osteopoenia)Physical stressHormone levelsRates of calcium and phosphate absorption and excretionGenetic and environmental factors

Diagnosing skeletal disordersLimitation of movementJoint involvement (mono-or polyarthritic?)InflammationSounds (bony crepitus)- grating soundsAbnormal bone deposits around fractures or jointsAbnormal posture

Congenital disordersOsteogenesis imperfecta- lack of bone collagen fibersMarfans syndrome- connective tissue disorder affects heart as wellAchondroplasia-epiphyseal plates are replaced by boneClubfoot(congenital talipes equinovarus) abnormal muscle developmentCleft palateSpina bifida

infectionsOsteomyelitis usually caused by S. aureusPagets disease apparently caused by virus

Malnutrition and bone disordersscurvyrickets

Secondary disorders can also affect skeletonEndocrine (giantism)Autoimmune (rheumatoid arthitis)Gout (digestive)

How do joints faciliate bone movement?