OVERVIEW OF ARTHROLOGY

Question 1

Joint elements - synovial joints

Answer 1

proximal and distal bone

(from superficial to deep):

-ligaments- restricts motion (extracapsular)
-joint capsule
-synovial membrane
-articular cartilage on the surface of the proximal and distal bones
-joint space filled with synovial fluid

SPECIAL JOINT ELEMENTS - distributes forces and provides additional joint stability/congruency
-fibrocartilage:
—meniscus (knee) - distributes forces at the joint
—articular disc (AC, SC, TM)
—labrum

Question 2

Hilton’s Law

Answer 2

“one often finds that a nerve that innervates a joint also tends to innervate the muscles that move the joint and the skin that covers the distal attachments of those muscles”

elbow: radial, median, musculocutaneous, ulnar nn.

knee: femoral, sciatic,obturator

Question 3

planar joint

Answer 3

primary motion is gliding of the two surfaces on one another

gliding in all directions

EX: AC joint, SI joint, most spinal facet joints

Question 4

hinge joint

Answer 4

flexion and extension

ex: humeroulnar, tibiofemoral, PIP and DIP

Question 5

saddle joint

Answer 5

both bones have convex and concave surfaces

-flexion, extension

EX: 1st CMC joint, SC joint

SC joint movements:
sagittal Plane: Anterior & Posterior Rotations. Frontal Plane: Elevation & Depression. Transverse Plane: Protraction & Retraction.

CMC joint: 1st:
-flexion and extension
-palmar abduction/adduction
-radial abduction/adduction
-circumduction
-opposition

Question 6

ellipsoidal joint

Answer 6

EX: 2nd MCP joints

-F/E
-abd/add
-rotation/ circumduction

Question 7

pivot/trochoid joint

Answer 7

EX: AA joint PRUJ

Question 8

arthrology/joint surfaces rule

Answer 8

convex on concave
-roll and glide of one bone in opposite directions

concave on convex
-roll and glide of one bone in the same direction