WEEK 8 Flashcards
what are the three joints of the elbow
- humeroulnar
- humero radial
- proximal radioulnar
describe the elbow joint (x3)
- synovial
- flexion and extension
- very stable joint with many ligaments to support
what are the two ligaments of the elbow and describe their role
1) medial collateral ligament
role= prevent abduction loads at the elbow
2) lateral collateral ligament
role= resists adduction of the elbow
describe the biceps brachii origin, insertion and roles
origin= scapula
insertion= radius
- a shoulder flexor and radioulnar supinator
- if in supinated position, bicep brachii moment arm will increase and therefore torque will increase.
describe the brachialis origin, insertion and describe its roles
origin= humerus
insertion= ulnar
role = not influenced by radioulnar supination or pronation
- brachial doesn’t attach to radius, instead to the ulna
describe the brachioradialis origin, insertion and its role
origin= humerus
insertion= radius
- radioulnar joints does affect its ability to produce torque
describe the influence of supination on the elbow flexion torque (x3)
- 20-25% greater supinated than pronated
- due to increased DMas of the bicep brachii when supinated
- when supinated the moment arm increases and produces more elbow flexion torque
describe the influence of supination on muscle recruitment (x2)
1- biceps brachii is recruited heavily when supination and flexion are combined and when the forearm us supinated , however not recruited heavily when the forearm remains pronated.
2- brachial recruitment is not sensitive to supination as it inserts onto the ulna. Consequently, brachial makes a relatively constant contribution to all forceful elbow flexor tasks.
describe an elbow dislocation ( x2)
- requires high force as ligament and joint capsule are very strong
- when this does occur- slow healing and long term rehabilitation
describe medial epicondylitis ( little league elbow) ( x3)
- valves forces of pitching
- affects flexor tendon and attachment to medial humerus epicondyle
- when throwing something there is a lot of force putting the wrist into extension
describe lateral epicondylitis ( tennis elbow) ( x3)
- common extensor attaching the the lateral epicondyle of the humerus
- not only related to tennis- swimmer, climbers and manual workers
- use wrist extensors to stop this from happening.
how the bicep brachii supinates
the bicep brachii is wrapped around the radius. as it shortens, the biceps brachii rolls the radius externally.
- in order for pronation or supination to occur it needs to be attached to the radius
describe the joints of the wrist (x2)
- synovial condyloid joint
- two different axis, flex and extend, also move in the front plane
describe muscles coordination
numerous muscles that act at the wrist also flex or extend the fingers. muscles in the adjacent quadrants represent helping synergists- they have antagonistic and common actions
define a colles fracture
distal radius fracture, posterior displacement of the wrist
mechanism= falling onto an outstretched arm
define a scaphoid fracture and the mechanism
def= the most frequently fractured carpal
- mechanism= falling on outstretched hand, wrist hyper extended
describe the upper extremity (hand) x3
- true synergy of the wrist when making a fist or a handle
- the ECRB prevents wrist flexion otherwise caused by FDS
- ECRB even causes mild wrist extension that increases grip strength
what are the 2 functions of the lower limb
- support of body weight
- locomotion
describe the hip joint, bones and ligaments
ball and socket joint
deep socket= very stable joint
- socket is deep so therefore less range of motion
list the prime extensors of the lower limb (x3)
1- gluteus maximus
2- long hamstrings
3- adductor Magnus
list the prime flexors of the lower limb ( x5)
1- iliacus
2- psoas major
3- rectus femoris
4- sartorius
5- tensor fascia latae
list the assistant flexors (x2)
- pectineus
- adductor longs brevis
describe hip flexors
ilacus, psoas major, rectus femoris , sartorius, tensor fascia lata.
- psoas attachments to the lumbar vertebrae have implications to lower back stress during hip flexion
describe psoas major and abdominal exercises (x2)
- some fear that the activation of this muscle may cause excessive lumbar disc stress
- it is through by many that the psoas major will be less active when crunches are performed with flexed hips.
