CHAPTER 8: JOINTS & MOVEMENT
I. JOINT = ARTICULATION = where 2 or more bones come together.
II. NAMING OF JOINTS
A. BONES THAT MEET = TEMPEROMANDIBULAR
B. BONE - HUMERAL - shoulder
C. GK or LATIN = CUBITAL - elbow
III. CLASSES OF JOINTS (Tab. 8.1, p. 249) [lo, hi, dives!!!]
- Named by major C.T. present
- Is joint capsule present w/fluid between bones
A. FIBROUS - fibrous tissue, no joint cavity, little/no movement
1. SUTURE
a. DENSE REGULAR C.T.
b. BETWEEN SKULL BONES
c. PERIOSTEUM continuous = SUTURAL LIGAMENT
d. WORMIAN BONES - in sutures
e. FONTANELS - wide sutures in newborns
f. SYNOSTOSIS = “joined by bone”, ossified suture
2. SYNDESMOSIS
a. connected by ligament
b. distal ends of radius & ulna
3. GOMPHOSIS
a. “peg in socket”, teeth in alveoli
b. PERIODONTAL ligaments
B. CARTILAGINOUS: BONE-CARTILAGE-BONE, slight movement
1. SYNCHONDROSIS: BONE-HYALINE CARTILAGE-BONE
a. COSTAL CARTILAGE - ribs to sternum
b. EPIPHYSEAL PLATES in long bones
2. SYMPHYSIS: BONE-FIBROCARTILAGE-BONE
a. Pubic symphysis
b. Intervertebral disks
C. SYNOVIAL - “FREELY MOVABLE”, joint cavity, synovial fluid
1. STRUCTURE (Fig. 8.7, p. 253)
a. 2 bones
b. Articular cartilage
c. Joint capsule
i. OUTER FIBROUS CAPSULE, w/ PERIOSTEUM
ii. INNER SYNOVIAL MEMBRANE
- Lines interior EXCEPT articular cartilage
- PRODUCES SYNOVIAL FLUID - lubricates, slick
Hyaluronic acid, proteins, fat, cells, serum
- BURSA - extension of capsule, sac
iii. SLOW REPAIR - poorly vascularized
d. ARTICULAR DISKS - FIBROCARTILAGE pads
e. LIGAMENTS - inside; strength & support
f. TENDONS - outside; strength & support
2. TYPES - (6) based on architecture (Tab. 8.2, p. 254; p.254-255)
a. PLANE/GLIDING - movement in 1 plane: vertebrae
b. SADDLE - 2 biconcave surfaces: carpometacarpal thumb
c. HINGE - cylinder in sleeve: elbow & knee
d. PIVOT - rotation around long axis: atlas & axis;
head of radius & ulna
e. BALL & SOCKET - 360o movement: shoulder; hip
f. ELLIPSOID - modified ball & socket: atlas/occipital
wrist; ankle
IV. TYPES OF MOVEMENT - in reference to S.A.P. (p. 255-259)
A. ANGULAR
1. FLEXION - ê angle @ joint, bend
EXTENSION - é angle @ joint, straighten
2. PLANTAR FLEXION - toes down, on tip toes
DORSIFLEXION - point toes up
3. ABDUCTION - away from sagittal plane, leg out laterally
ADDUCTION - towards sagittal plane, leg in medially
B. CIRCULAR
1. ROTATION - circular movement along long axis, head
2. CIRCUMDUCTION - “cone in space”, only @ ball & socket
3. PRONATION - palm down, forearm only
SUPINATION - palm up
C. SPECIAL
1. ELEVATION - up, shoulder, mandible
DEPRESSION - down, shoulders, mandible
2. PROTRACTION - chin out, anterior
RETRACTION - chin in, posterior
3. LATERAL/EXCURSION - towards side, mandible
MEDIAL - towards midline
4. OPPOSITION - thumb to pinkie, fingers
REPOSITION - open hand
5. INVERSION - sole of foot towards midline
EVERSION - sole of foot away from midline
D. COMBINATIONS
OMIT JOINTS p. 260 - 270