sub-discipline of kinesiology and the study of mechanical analogy of motion including physics, physiology, etc

study of the mechanical structure of a living organism using physics to describe structures and the analogy of machines to understand movement

shoulder, elbow, hips, and knee

self-lubricating, frictionless, weight-bearing, movable structures--which enable vertebrates and animals in general to do work

or immovable for strength of uniting 2 or more bones

typically named after bones involved in articulation

fused (anchylosis) osseous tissue

eg--frontal bones fuse, pre-maxilla fuse, bones of the mandible fuse together

collagenous joint

little or no movement

eg--cranial suture

bones held together by cartilage

slightly movable

eg--intercarpal, intertarsal, intervertebral joints

freely movable joint

eg--elbow

2 freely moving bones separated by a cavity filled with a lubricant synovial fluid

eg--jaw, shoulder, elbow, hip, and knee

structurally complex and can become uncomfortable and dysfunctional

healthy held separate by soft tissue and fluid by a joint (articular cavity)

fluid in joint/articular cavity

slippery and viscous; same consistency to a raw egg white

nourish articular cartilage and removes wastes by phagocytes

Hyaline cartilage

approx 2mm thick in young healthy joints

fibrous and encloses the joint cavity

2 layers: Fibrous capsule and Synovial membrane

outer layer of joint capsule

continuous with the periosteum

inner lining of the joint capsule

composed of areolar tissue and secretes fluid

cartilaginous pads that grow inward from the joint capsule

act as shock absorbers

holds the articulating bones in position to avoid dislocations

distributes pressure evenly during work

attach a muscle to bone together by strips or sheets of collagenous connective tissue

stabilize joints

fibrous sac filled with synovial fluid and cushions muscles

help tendinal movement

can enhance mechanical effect (advantage)

equals load and effort;

which is the energy needed to overcome it

MA = L_E/L_R

If MA > 1 -- lever produces more force, but less speed or distance

If MA < 1 -- lever produces more speed or distance, but less force

fulcrum is in the middle

example: seesaw

resistance is in the middle

example: lifting the handles of a wheelbarrow

effort is in the middle

most musculoskeletal levers are this kind

example: forearm acts as this when elbow is flexed; fulcrum is joint between ulna and humerus; effort is applied partially by biceps brachii; resistance is any weight in the hand or weight of forearm itself

shoulder and hip--only multiaxial joints in the body

hemispherical head fits into a cup-shaped socket (humeroscapular)

convex surface fits into a concave surface; monaxial (one plane of movement)

limits lateral movement

examples: elbow, knee, and finger/toe joints

saddle-shaped joint; both articulating surfaces are concave

biaxial

example: thumb and sternoclavicular joint

rotational movement at a single point; monaxial

examples: atlantaoaxial joint between first 2 vertebrae and radioulnar joint at the elbow

flat articular surfaces move (slightly) over an adjacent bone; monaxial

examples: found between bones of carpals, tarsals, and articular processes of the vertebrae

oval convex surface articulates with a complimentary concave surface; biaxial

examples: radiocarpal joint and base of fingers (spread fingers apart)

decreases a joint angle; common in hinge joints

raise arm/raise thigh

movement that straightens a joint and returns a body part in zero position (anatomical position)

examples: straightening elbow/wrist/knee; returning arm/thigh to zero position; hip and knee in stair climbing

furthur extension of a joint beyond the zero position

examples: admiring a ring = wrist; backswing of lower limb when you walk = hip

movement of body part in the frontal plane away from the midline of the body

example: spreading legs, raising arm to one side

hyper: arm if you raise it high enough to cross slightly over front or back of your head

movement in the frontal plane back toward the midline

hyper: stand with ankles crossed, cross fingers

movement that raises a body part vertically in the frontal plane

example: lifting suitcase, important for chewing

movement that lowers a body part in the frontal plane

example: setting down a suitcase, important in chewing

anterior movement of a body part in the transverse/horizontal plane

example: shoulder when you push door open

posterior movement of a body part in the transverse/horizontal plane

example: shoulder returns back to zero position after pushing door open; military attention

one end of an appendage remains stationary while the other end makes a circular motion

example: pitcher windmill; individual finger, hand, thigh, foot, trunk, and head

movement in which a bone spins on its longitudinal axis

example:
medial-bend elbow, move forearm medial, humerus spins

lateral-forearm points away from body, humerus spins

forearm movement that turns palm to face anteriorly/upward

example: in anatomical postion, forearm is this and radius is parallel to ulna

forearm movement that causes the palm to face posteriorly/downward

example: radius crosses the ulna like an X

twisting at the waist or turning of the head when chest when face turns right or left

important in pitching and discus

movement to the left or right of the zero position

side-to-side movement of the mandible

movement back to the median, zero position

side-to-side movement of the mandible

tilts the hand toward to little finger

example: waving

tilts the hand toward the thumb

example: waving

moves thumb away from plane of hand so it points anteriorly

example: wrap hand around tool

movement in which toes are elevated

example: applying toenail polish, foot does this as it comes forward in walking

powerful movement of the foot so the toes point downward

example: pressing gas pedal, standing on tip-toes, jump-shots

foot movement that tips the soles laterally, away from each other

example: fast sports, ankle sprains

jaw joint

combines condylar, hinge, and plane joints

lateral and sphenomandibular ligament support this joint

shoulder or glenohumeral joint

most freely movable joint (shallow gleniod cavity and loose joint capsule) in the body and frequently injured

supported by 5 ligaments

strap to hold humerus in place against glenoid cavity

held in groove by transverse humeral ligament

merges with biceps brachii

O: glenoid cavity

tendons of four muscles that also stabilize the shoulder

supraspinatus, infraspinatus, teres minor, subscapularis

primary weight-bearing ball-and-socket joint for bipedal human

articulation of the femur head and the os coxae of the acetabulum

support provided by several ligaments that hold femur to acetabulum

distinctive ligament from the head of the femur to the lower margin of the acetabulum

contains an artery that supplies blood to the head of femur

largest and most complex diarthrosis joint of the body; it is a hinge joint

joint capsule encloses the sides and back of knee

ligament in the knee joint that prevents hyperextension of the knee

excluded from fluid-filled synovial cavity

most knee injuries; damanged ligaments can be replaced with a graft