MS exam I joints and hip ligs

bridges the gap in the acetabular labrum, but leaves space underneath itself so vessels can pass under

• aka round ligament
• runs from fovea to either side of acetabular notch
• protected by fat
• doesn't play much of a mechanical roll
• the acetabular branch of the obturator artery runs thru it, supplying some blood to head of femur

• a ligament on the neck of the femur formed by the circular fibers of the articular capsule of the hip joint
• surrounds the head and runs down like a noose around the head and neck, hourglass shaped
• narrower than the head
• function: acts biomechanically as a locking ring wrapped around the femoral neck
• and thus is a key structure for hip stability in distraction

lower AIIS and rim of acetabulum to entire length of trochanteric line

• superior portion of the iliofemoral ligament
• limits extension and adduction
• runs down to upper part of intertrochanteric line

• creates the bottom part of the Z with the Y lig
• med: ant of iliopubic eminence, sup ramus of pubic bone, and obturator crest
• lat: ant surface of trochanteric fossa

limits: extension and abduction and ER

• post: post surface of the acetabular rim and labrum ---> sup/lat:  inner surface of greater trochanter ant to trochanteric fossa
• limits: extension, abduction, medial rot

(anterior lig,) iliofemoral lig, pubofemoral lig

ischiofemoral

• pubofemoral and ischiofemoral
• and info part of iliofemoral lig

iliotrochanteric lig (that's the sup part of the iliofemoral lig)

• simple - just 2 bones articulating
• compound - more than 2 bones
• complex - has meniscus

• simple - has axis at right angle
• complex - axis not at right angle

• spheroid surface w 3 axis and 3 degrees of freedom
• ball and socket joint

• ellipsoidal
• 2 axis and 2 degrees of freedom (no rotation)
• condylar
• ex. MCP joint

• saddle joint
• 2 axis and 2 degrees of freedom
• concave in 1 dir, convex in other
• ex. 1st CMC

• hinge
• 1 axis and 1 degree of freedom
• ex. elbow

 A joint in which a section of a cylinder of one bone fits into a corresponding cavity on the other, as in the proximal articulation between the radius and ulna.

• have no genuing joint space
• no fluid
• bones are divided by tissue
• 3 types: syndesmosis, synchondrosis, synostosis

• type of synarthosis joint
• fibrous tissue between bones
• ex - distal tib-fib joint

• type of synarthrosis joint
• cartilagenous tissue btwn bones
• ex: costochondral joint

• type of synarthorsis joint
• bony tissue btwn bones (so it's really bone on bone)
• ex - bony sutures in skull

• symphyses - connecting tissue partly fills the joint  ex-pubic sympysis
• synoviales - moveable joints with all the characteristics of synovial joints

• amphiarthroses <10 degrees of movement
• articulations >10 degrees of movement

pure rotation around a mechanical axis

• any movement other than pure spin
• pure or cardinal swing - the shortest route btwn 2 points
• arcuate or impure swing - a longer route; rotation added to swing

• movement of the long bone
• movement in the joint

• one point on a moving survace comes in contact w new points on another surface
• (picture your knuckles dragging across your other palm)

• new points on one surface come in contact with new points on another surface
• (picture knuckles of each fist rolling against each other)

an arc surface slides over another surface w/o adding another component (like sliding/gliding, but over a curved surface)

increase or decrease in the angle formed btwn 2 adjacent bones (ex. valgus + varus in knee)

• sup: horizontal, called illiotrochanteric band
• middle:  is weak
• inf: oblique, inserts into lower trochanteric line

• ext
• ER
• adduction (the iliotrochanteric band)
• abduction (only the inf part)

• abd 
• ext
• ER

spirals superolat over neck of femur from post acetabulum to greater trochanter