Chapter 7 Upper Extremity Injuries

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
• 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
• 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 gt 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
• mostly anterior when arm is abducted, extended
  and ext. rotated
• posterior forces
• Posterior luxation
• same mechanism reverse
• Inferior luxation

9
Shoulder Injuries

• Impingement
• 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

• Rotator cuff impingements
• 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
• 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
• MCLvalgus 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 30-50 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
• large varus torque
• Mechanism
• 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
• olecranonimpact or hyperextension
• Radial
• axial loading of radius from a fall or dislocation

20
Forearm Anatomy

• Two bones
• radius ulna
• Two compartments of muscles
• anterior flexor-pronator
• posteriorextensor-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
• 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)
• Bowlers thumb ulnar digital nerve trauma
• tingling, sensitivity

28
Wrist Hand Injuries

• Metacarpal phalangeal injuries
• Fractures
• Boxers
• Dislocations