1)What is a joint?
Functional junctions between bones
2)How are joints classified?
Structurally: fibrous, cartilaginous, synovial
Functionally: immovable, slightly moveable, freely moveable
3)Describe the 3 types of fibrous joints.
•Syndemosis: sheet or bundle of dense connective tissue
•Sutures: only between flat bones of skull
•Gomphosis: binds teeth to bony sockets
4)What is the function of the fontanels?
Allows the skull to slightly change which allows the infant to pass through the birth canal more easily.
5)Describe two types of cartilaginous joints.
•Synchondrosis: bands of hyaline unite the bones
•Symphysis: bones are covered by a thin layer of hyaline cartilage, and the cartilage is attached to a springy fibrocartilage. 6)What is the function of an intervertebral disc?
They absorb shocks and help equalize pressure between the vertebrae when the body moves 7)Describe the structure of a synovial joint.
Two bones are held together by a joint capsule composed of two layers. Ligaments help reinforce the capsule. The cavity between the bones are filled with a viscous fluid called synovial fluid. 8)What is the function of the synovial joint?
Allow free movements
9)Name six types of synovial joints and describe the structure of each. •Ball + Socket: globular shaped head articulates with a cup shaped cavity •Condylar: Ovoid condyle of one bone fits into the elliptical cavity of another •Plane/Gliding: nearly flat or slightly curved
•Hinge: convex surface of one bone fits into concave surface of another •Pivot: the cylindrical surface of one bone fits rotates in a ring formed of a bone and a ligament. •Saddle: articulating surfaces have both convex and concave surfaces. 10)Define the following movements and give an example.
Flexion-bending parts, angle decreases, parts come closer
Extension-moving parts, angle increses, parts move farther away Hyperextension-extension beyond anatomical position Dorsiflexion-movement at the ankle that brings the foot closer to the shin Plantar flexion-moves the foot farther from the shin Abduction-moving part away from the midline, raising the arm Adduction-moving part toward the midline
Rotation-moving part around on an axis
Circumduction-moving a part so the end follows a circular path Supination-rotation of forearm so the palm is upward
Pronation-rotation of forearm so the palm is downward Eversion-turning the foot so plantar surface is facing laterally Inversion-turning the foot so the plantar surface is facing medially Protraction-moving a part forward Retraction-moving a part backward
Elevation-raising a part
Depression-lowering a part
11)Describe how a movement occurs at a joint when a muscle contracts. The fibers pull the moveable end (insertion) towards its fixed end (origin) 12)What part helps to keep together the articulating surfaces of the shoulder joint? •Coracohumeral ligament
•Transverse humeral ligament
13)What factors allow an especially wide range of motion in the shoulder? •The looseness of its attachments
•Large articular surface of the humerus compared to the shallow depth of the glenoid cavity 14)What structures form the hinge joint of the elbow?
Trochlea of the humerus and the trochlear notch of the ulna
15)Which parts of the elbow permit pronation and supination of the hand? The head of the radius
16)Which structures help keep the articulating surfaces of the hip together? •Iliofemoral ligament
17)What types of movements does the structure of the hip permit? •Flexion
18)What types of joints are in the knee?
•Modified hinge joint
19)Which parts help hold together the articulating surfaces of the knee? •Patellar ligament
•Oblique popliteal ligament
•Arcuate popliteal ligament
•Tibial collateral ligament
•Fibular collateral ligament
20) Describe the following joint disorders.
Sprain -over streching or tearing the connective tissues
Bursitis-overuse of a joint or stress on a bursa
Rheumatoid Arthritis (RA)- immune system attacks body’ healthy tissues. Synovial membrane becomes inflamed and thickens. Then articular cartilage is damaged, fibrous tissue infiltrates and interferes with joint movement. Osteoarthritis-articular cartilage softens and disintegrates gradually Lyme Arthritis-casues intermittent arthritis of several joints 20)Which type of joint is the first to show signs of aging? Fibrous
21)Describe the loss of function in synovial joints as a progressive progress (while aging). •Begin in 30’s but progresses slowly
•Fewer capillaries serving synovial membrane; slows circulation of synovial fluid; resulting in a possibility of stiffening •More collagen cross-links shorten and stiffen ligaments; affecting range of motion