REGIONAL CONTENT Flashcards
Describe the arthrology of the 3 shoulder joints
Glenohumeral (GHJ) = synovial ball and socket
Acromioclavicular (ACJ) = synovial plane
Sternoclavicular (SCJ) = synovial saddle
Describe Conjunct Rotation
A consequence of ligament tightening
Describe a Clavicle Fracture
Most common in middle 1/3
Describe a Scaphoid Fracture
Most common carpal fracture
Describe Nutation
- base of sacrum moves anteriorly and inferiorly, relative to ilium
- anterior tilt
Describe Counternutation
- base of sacrum moves posteriorly and superiorly, relative to ilium
- posterior tilt
Describe Femoral Anteversion
- from a superior view point
- line through back of femoral condyles and line through the neck of femur > where they intersect is the angle
- normal = 15 degrees
Describe the Femoral Angle of Inclination
- angle of inclination of neck of femur, relative to shaft of femur
- normal = 125 degrees
Describe Coxa Valga
- angle of inclination greater than 125 degrees
- decreases bending moment
Describe Coxa Vara
- angle of inclination less than 125 degrees
- increases bending moment
Describe how GLUTEUS MAXIMUS has multiple actions for different segments
Superior portion = abduction
Inferior portion = adduction
Both = hip extension
Describe how GLUTEUS MEDIUS has multiple actions for different positions
In 0 degrees flexion (anatomical position)
- anterior compartment = medial rotation
- middle & posterior compartment = lateral rotation
In flexion
- anterior compartment = medial rotation
- middle & posterior compartment = medial rotation
Describe the actions of ADDUCTOR MAGNUS
From 0 degrees flexion to 90 degrees flexion
= hip extension
Describe how ADDUCTOR LONGUS AND BREVIS have multiple actions for different positions
In 0 degrees flexion = hip flexion
In 90 degrees flexion = hip extension
Describe the 3 major points of the SCREW HOME MECHANISM
- length of femoral condyles: longer articular surface on medial femoral condyle which facilitates the screw home mechanism
- when extending, the lateral femoral condyle completes it articular surface while the medial femoral condyle is longer, so it keeps going past its articular surface, causing internal rotation of femur on tibia
- the screw home mechanism provides stability in standing by tightening ligaments
Describe Menisci: Tibial plateau vs. femoral condyles
Tibial plateau
- relatively flat
- posterior slope in standing : provides some resistance to anterior translation of femur on tibia
Femoral Condyles
- flat on midportion but predominately round
Describe Menisci: Function
- increase congruency/ contact area between femoral condyles and tibial plateau
- same force over greater area = decreased stress
- protects underlying articular cartilage
Describe Menisci: Medial meniscus
- medial meniscus is longer with expanded posterior horn
- despite its larger size, the medial meniscus provides less coverage to tibial plateau
- medial meniscus does most weight bearing and has hi[-knee 1 degree varus, creating varus moment and further increasing force on medial side
Describe the Mechanical Axis
- represents load bearing axis
- measured from centre of femoral head to centre of talus
- normal mechanical axis = 179 degrees or 1 degree varus
Describe the Anatomical Axis
- represents a line through anatomical components
- line through shaft of femur and line through shaft of tibia
- intersecting angle (normal) = 5 degree genu valgus
Describe a Navicular Stress Fracture
- most common tarsal bone to fracture
- central zone of hypovascularity
- medial and lateral compressive forces through 1st and 2nd ray > maximum tensile load = central 1/3
Describe the components of the Medial Longitudinal Arch of foot
Calcaneus, talus, navicular, medial cuneiform, MT 1-3 and rays 1-3
Describe the components of the Lateral Longitudinal Arch of foot
Calcaneus, cuboid, MTs and phalanges
Describe the components of the Transverse Arch of the foot
MTs and cuneiforms
Describe 4 functions of the arches of the foot
- protect tendons and neuromuscular structures
- energy return and shock distribution for running
- stability to bones
- allows deformable feet for walking