Types Of Synovial Joints & introductory stuff

Question 1

Plane joint

Answer 1

2 flat surfaces slide against each other in several directions one plane

E.g. carpal bones wrist

Question 2

Condyloid joints

Answer 2

2 Bowles nested together, may directions one pane

E.g. atlanto-occipital joint base of skull

Question 3

Saddle joints

Answer 3

Motion two planes simultaneously, degree of sliding

E.g. 1st carpometacarpal joint base thumb

Question 4

Hinge joints

Answer 4

Stable flexion and extension without sliding, single plane

E.g. elbow joint between humerus and ulna

Question 5

Pivot joints

Answer 5

Peg and ring shaped hole, rotational motion without gliding

E.g. Atlanta-axial joint head to rotate while maintains stability of head on neck

Question 6

Ball and socket joints

Answer 6

Stable movement several directions without slippage, most mobile permit flexion-extension, abduction-adduction, lateral-medial rotation and circumduction

E.g. hip and shoulder

Question 7

Embryological development of synovial joints

Answer 7

Synovial joint interruption cartilage model of bone. 6th week mesecnhyme differentiate into hyaline cartilage, spaces between = joint interzone cells centre undergo apoptosis-> joint cavity, surrounding mesenchyme cells from perichondrium form periosteum, articulate cartilage, supporting ligaments. (Some cartilage in knee joint preserved for intra-articulations ligaments)

Question 8

3 types of muscles contractions

Answer 8

Concentric- muscles shortens as contracts e.g. flexion elbow biceps brachii (most common)

Eccentric- muscle lengthens as contracts e.g. lowering dumbbell biceps brachii

Isometric- no change in length e.g. carrying an object/ gripping something

Question 9

Parallel muscles

Answer 9

Fibres run parallel to force generating axis

Strap- fibres run longitudinally
Fusiform- cyclindrical wide centre tapering at ends
Fan-shaped- fibres converge at one end

Question 10

Pennate muscles

Answer 10

One or more aponeuroses from tendon to fascicles attach at pennation angle

Unipennate- fascicles same side of tendon
Bipennate- fascicles both sides of central tendon
Multipennate- central tendon branches

Question 11

Circular muscles

Answer 11

Fibres form concentric rings around a sphincter/ opening attach to skin/ligaments/fascia rather than bone

Question 12

Radiological union of fractures

Answer 12

Adults 3-12 weeks
Inflammatory phase- hrs to days (haematomma, tissue death, inflammation, cell proliferation)no callus seen

Reparative phase- days to weeks (angiogenesis, granulation, procallus, soft callus fluffy, hard callus)

Remodelling phase - months to years (fracture lime obscured = radiographic union)