Upper extremity Flashcards
Functional articulations of shoulder complex
Shoulder girdle inc ROM with less compromise of stability
Jts of shoulder
Sterno-clavicular
Acromio-clavicular
Scapulo-thoracic
Gleno-humeral (ball and socket)
Supra-humeral/sub-acromial
LH biceps and bicipital groove
Role of long and short head of bicep
Ant stability of GH, therefore failure of stabilisation of LHB can have damaging effects on GH and rotator cuff function
Achieved through compression of humeral head against glenoid fossa
Humeral head stability= compression of humeral head to glenoid fossa, doesn’t go into subacromial space
Evidence that LHB enables GH stability
LHB hypertrophies in Px with rotator cuff tears
Scapulo-humeral rhythm
Rare at ahwihc scapula moves relies on rate at which humerus moves
Permits larger ROM
Shoulder girdle inc ROM with less compromises to stability
Facilitate movement of upper extremity by positioning GH favourably
Force coupling
Around a pivot (SC Jt)
Opposing forces in scapula rotate around pivot point
Multiple forces at once
Can be equal or unequal, depending on function required and balance of stabilising elements such as ligaments
Roll and glide GH
Convex-concave- convex rolls and slides in opposite directions
Helps maintain Jt congruity and articular surface contact through ROM
Concave= glenoid fossa of scapula
Covnex= head of humerus (spins in flex/ext)
Scapular is fixed
Active movement driven by humerus
Roll and glide principle SC
Convex-concave- convex rolls and slides in opposite directions
Helps maintain Jt congruity and articular surface contact through ROM
Concave= manubrium
Convex= proximal clavicle
Clavicle and manbrium passive
Active driven by humerus and scapula
Importance of sub acromial space
Location of bicep tendon, rotator cuff and bursa
Can become pinched during some shoulder movements
Role of clavicle
Attaches axial and appendicular
Only attachment point for upper limb
Elevates, depresses, rotates, protracts, retracts- all movements passive and accessory
All movements allow acceptance of head of humerus by scapular
All movements of GH Jt involve some movement of clavicle around pivot point of SC jt
Role of coracoid process
Ant anchor of scapula- e.g., pec minor, corocobrachialis, short head of bicep
Movers GH
Deltoid
Supraspinatous
Biceps brachii
Brachioradialis
Pec major
Stabilisers GH
Subscapularis
Serratus ant
Lats
Coracobrachialis
Pec major
Ligaments also necessary
Identify cause of painful and weak shoulder
Rotator cuff related shoulder P
Subacromial impingement syndrome
SLAP lesion
Identify cause of painful and stiff shoulder
Adhesive capsulitis
OA (bony remodelling) of GH, AC
Identify cause of painful and unstable shoulder
Dislocations
Repeated dislocations
Elbow torques
Flexion torques are 70% greater than ext torque
Torque forces needed for bicep curl are 70% greater than an ext push down
Flex torque with supination is 20% greater than with pronation
Brachioradialis in mid prone inc power of flexion
Elbow levers
3rd class lever- during flexion
Effort= muscle (at point of insertion)- e.g. bicep
Load= weight of body and additional resistance
Fulcrum= Jt itself
Elbow roll and glide
The concave-convex surface movement, the concave surface rolls and slides in the same direction
This helps maintain articular surface contact and Jt congruity through ROM
Concave= ulnar
Convex= humerus
Humerus is passive in both flex and ext, driven by active movement of ulnar and radius
Mechanics of grip
Lumbricals allow for L-shape grip
Examples of mechanical principles in elbow
- Lever- 3rd class
- Force- torque in pronation/supination
- Roll/slide- proximal humerus-radius/ulnar roll- slide in same direction
- Flexion force- 70% greater than ext, 3x bicep, 1x triceps
- Stabiliser- interosseous membrane
- 90 pro/supination, 140-150 flex
Examples of mechanical principles of wrist
- Ulnar/radial deviation ROM- 30-45, 15
- Roll and slide mechanism in radial/ulnar deviation
- Movement driven by carpals, radius is passive, carpals roll and slide in different directions around pivot point of capitate
- Role of lumbricals- allow for L-shaped grip, inc stability
Describe kinematics of pro/sup of forearm
Comment on ROM, types of movement, roll and slide concept
90 pro/sup
Torque force
Roll + slide mechanism- same direction- radial/ulnar/humeral
Roll + slide- radial/ulnar Jt
Stabilising effects of interosseous membrane
Describe kinematics of flex of elbow
ROM, type of movement, roll and slide concept, type of lever
3rd class
120-140 flex
Humerus convex, ulnar concave
Roll + slide in same direction
Flexibility of capsule allows flex/ext
