1. Chapter 7 - Upper Extremity Injuries
Impair peoples’ ability to manipulate the environment. Upper extremity design for motion not for the support of large loads

2. Shoulder Anatomy Shoulder complex: Sternoclavicular joint:
Shoulder girdle: scapula and clavicle
Shoulder joint joint
Sternoclavicular joint:
Modified Ball & Socket
disk
Acromioclavicular joint
AC ligaments
Coracoclavicular joint
Glenohumeral joint:
Scapulothoracic joint

3. Shoulder Anatomy Glenohumeral Joint Muscular support Most mobile joint
Shallow joint cavity
Glenoid labrum
Glenohumeral ligaments
Coracohumeral ligament
Muscular support
Rotator cuff muscles

4. Shoulder Anatomy Rotator cuff
subscapularis
infraspinatus
supraspinatus
teres minor
Primary source of stability to the shoulder

5. Shoulder Anatomy

6. Shoulder Injuries AC sprain or separated shoulder
Indirect or direct forces
direct force to acromion with shoulder in adducted position
fall on a outstretched arm
traction to arm
Classification
Type I-III
Type IV > rare
severe forces

7. Shoulder Injuries Shoulder instability poor joint cavity poor ligament
musculature
Intracapsular pressure
Concavity compression
scapulohumeral balance

8. Shoulder Injuries Anterior Luxation Posterior luxation
mostly anterior when arm is abducted, extended and ext. rotated
posterior forces
Posterior luxation
same mechanism reverse
Inferior luxation

9. Shoulder Injuries Impingement Categories
glenohumeral joint: abduction
supraspinatus and bursae
Categories
Under 35 year: sports or jobs with overhead movement
Older: degeneration
Microtrauma-instability-subluxation-aggravation

10. Shoulder Injuries Mechanism Rotator cuff impingements Intrinsic
Extrinsic: structural factors
hook acromion
hypertrophy of supraspinatus
Intrinsic
inflammation of the tissue
Mechanism
work of sports requiring overhead movements
Wheelchair (abductor dominance)

11. Shoulder Injuries Rupture Rotator cuff Chain of events:
inflammation
microtears
partial or total rupture
movement adaptations
Supraspinatus rupture most common
Eccentric actions
acceleration phase
decceleratiom phase

12. Shoulder Injuries Upper arm Humeral fractures two compartments
anterior
posterior
Humeral fractures
7% of fractures
Direct or indirect
Low & high energy
falls, car crashes, direct loading, violent muscle contraction (throwing)

13. Shoulder Injuries Biceps tendon injuries tenosynovitis (repetition)
dislocation (medial)
abduction/ext. rotation
falls outstretched arm
lateral impact
hyperextension
anterior GH dislocation
bicipital grove angulation
rupture: tissue degeneration
SLAP

14. Elbow Anatomy Hinge joint Ligament support Muscles MCL:valgus loading
LCL: varus loading
Annular ligament
Muscles
Flexors: biceps, brachialis and brachioradialis
Extensor: Triceps & anconeus

15. Elbow Injuries
Epicondylitis: repeated loading causing microtrauma and tissue degeneration leading to inflammation and tissue weakness
Lateral epicondylitis
tennis players years old, poor stroke mechanics, excessive muscle contraction
Overuse of extensor mechanics, pinching and grasping

16. Elbow Injuries Medial epicondylitis
excessive loading forehand and serve
Advanced players
Wrist motions

17. Elbow Injuries Valgus Extension Loading Mechanism large varus torque
elbow extension
huge internal rotation torque transmitted to elbow

18. Elbow Injuries Dislocations more stable, less incidence of dislocation
Axial force to extended or hyper
Avulsion of collateral ligaments

19. Elbow Injuries Fractures humeral Ulnar Radial
olecranon:impact or hyperextension
Radial
axial loading of radius from a fall or dislocation

20. Forearm Anatomy Two bones Two compartments of muscles
radius & ulna
Two compartments of muscles
anterior: flexor-pronator
posterior:extensor-supinator
Proximal radioulnar joint
Distal radioulnar joint

21. Forearm injuries Diaphyseal fractures of ulna & Radius
Galeazi: distal 1/3 radius, outstretched arm, blow to dorsum of wrist
Nightstick
Montegia lesion: classification for ulnar fractures
Distal radius: Colles etc.

22. Forearm injuries Ulnar variance: relative length of ulna and radius
Determined
genetics
elbow pathology
mechanical loading
Ulnar variance in gymnast-premature closure of radial growth plate
Gymnastic: huge loads to the wrist- cartilage degeneration/fractures

23. Wrist & Hand Anatomy Wrist joints Hand joints CM: MP: condyloid
distal radio ulnar
radiocarpal
intercarpal
Hand joints
CM:
MP: condyloid
IP: hinge

24. Wrist & Hand Anatomy Strong ligaments Muscles
control wrist & finger motion
carpal tunnels
Flexor & extensor retinacula

25. Wrist & Hand Injuries Carpal tunnel (CTS)
result from repetitive stress to tissue
64% of work injuries
Compressive neuropathy
Wrist flexion/ext and finger movements
Risk factors
exertion
repetitive stress
posture
localized contact
cold

26. Wrist & Hand Injuries Carpal fractures
compressive loads to hyperextended wrist
hyper flexion
rotation loading against a fixed wrist
Scaphoid
60-70%
Lunate

27. Wrist & Hand Injuries Thumb: essential to prehension
Sprain: skiers thumb
fall with thumb in abducted position
tensile loads on MCL
Hyperextension
Bennets fracture (fighting)
Bowler’s thumb: ulnar digital nerve trauma
tingling, sensitivity

28. Wrist & Hand Injuries Metacarpal & phalangeal injuries Fractures
Boxers
Dislocations