Flashcards in Week 4 - Clinical Correlations of Upper Extremity Deck (33):
What muscle is used most when a pitcher throws?
Subscapularis - it does internal rotation
-Rotator cuff muscle
-movement between humerus and scapula
What rotator cuff muscles do external rotation?
Infraspinatus & Teres Minor
What rotator cuff muscles elevate?
What are the more common causes of rotator cuff pathology?
Age related degenerative tears & tendon degenerative processes
What are the less common causes of rotator cuff pathology?
-Young athletes or laborers
-Acute, injury related tears
When can the radial nerve be easily injured?
-Patient unable to straighten wrist
What can cause damage to median or ulnar nerves?
When are vascular injuries rare with broken bones?
When the arm doesn't get cut (no laceration or open injury) damaging an artery or vein is difficult.
What is Lateral Epicondyle pain?
Tennis elbow - tendonopathy
-Tendon disease of extensor tendon origin (ECRB)
Treat: activity modification, gentle physical therapy, time
What is medial epicondyle pain? How to treat?
Golfer's elbow - tendonopathy
-Tendon disease of flexor-pronator origin
Treat: activity modification, physical therapy, time
What is the common childhood dislocation?
"Nursemaid's elbow" - from picking up a kid
-Dislocation of the radial head from the humerus (where radius meets capitelum)
-Usually traction (pulling) injury
-low energy injury
-Major ligaments are still in tact
What is an X-ray?
Radiation based, high power photograph, radiograph, plain film, bone
What is a CT/CAT?
Computed (axial) tomography, Radiation based, greater detail & 3D capabilities - Injections of contrast can be given to see more detail/information
-Bone, solid organs
What is an MRI?
Magnetic Resonance Imaging
-Image quality related to power of magnet & size of coil
-NOT radiation based - heating of tissues can be an issue
-Can see: soft tissues, cartilage, muscles, tendons, brain
What causes longitudinal instability of the forearm?
Disruption of the interosseus membrane
Why is the interosseous membrane important? Does the ulna move?
The interosseous membrane is important because it helps trade weight back and forth from the radius to the ulna.
The Ulna has no rotation in the forearm.
What happens in avascular wrist pathology?
The bone loses circulation and wrist bones 'die'
What is the most common fracture of the arm?
Distal radius fracture (usually falling on wrist) - has/bears most force in the wrist
What is the most common fracture of carpal bones?
Scaphoid - it doesn't like to heal and this can cause big problems
What causes carpal tunnel?
Swelling of the flexor tendon synovium pinches the median nerve as it goes across the wrist
-Can be caused by overuse, trauma, medical conditions: Rheumatoid arthritis, neuroma
What symptoms does carpal tunnel cause?
Sensation changes, pain
Loss of strength in thenar muscles
What does an Ulnar nerve injury cause?
Loss of sensation
Loss of fine motor control of intrinsic muscles: (1) Lumbricals - 3rd and 4th (2) Dorsal Interossei (3) Palmar interossei
-Pathology can occur at wrist or elbow
What can a radial nerve injury cause?
Injuries at elbow or forearm to posterior interosseus nerve: LACK of thumb or finger EXTENSION & no change in sensation
Injury to superficial branch of radial nerve: SENSATION changes, no loss of strength
What are the location of the intrinsic hand muscles, from most palmar to most dorsal?
Lumbricals -> palmar interossei -> dorsal interossei
What are the intrinsic muscles of the hand responsible for?
-Metacarpal phalangeal joint flexion
-Proximal interphalangeal joint extension
-Distal interphalangeal joint extension
What is the function of the doral interossei?
Abduct the fingers
What is the function of the palmar interossei?
Adduction, flexion & extension of fingers
What are the functions of the lumbrical muscles?
-Flex metacarpophalangeal joints
-Extend interphalangeal joints
What happens as the interossei come together with the lumbricals?
They become one tendon, which starts on the palmar side and moves to the dorsal side over the PIP and DIP joints.
What helps flex the MP joint?
Flexor tendons & all three intrinsic hand muscles
What is a swan's neck injury?
"Baseball player injury" - Flexed DIP joint and hyperextended PIP joint
Where do extensor muscle tendons stop?
Most stop at the MP joint & help extend this.