Hand, Digits, Thumb: Exam 3

Front 1

A 28-year-old gymnast experienced vague pain in the anterior region of his shoulder joint. He said that he had the sensation of popping during his parallel bar routine.
• During the preliminary examination, the coach noted tenderness over the bicipital groove, flexion and supination weakness of the forearm, and an abnormal bulge in the anterior part of the gymnast's arm.
• During a subsequent radiographical examination, a fracture of the scapula was observed.

1) What muscle is most likely injured?
2) What does the popping sensation and tenderness over the bicipital groove suggest?3) Weakness of what forearm movements would support your hypothesis?
4) What probably caused the abnormal bulge in the anterior part of the gymnast's arm?
5) What scapular fracture could be associated with this arm injury?

Back 1

1) biceps brachii
tendon of long head of biceps goes through intertubericular groove.
2) tendon has been pulled down w/ excessive force off of its bony attachment
3) supination and flexion of forearm
4) tendon fell down
5) supraglenoid tubercle of scapula fracuture causes dislocation of the long head of the biceps and causes it to dislocate from the intertubercular groove

Front 2

What are 2 classes of movements for hands

Back 2

non manipulative prehension patterns: strength related
manipulative prehension patterns

Front 3

Name some movements under non-manipulative prehension patterns

Back 3

1. cylindrical grip
2. hook grip (comes from flexion, bennding of fingers)
3. sphreical grip -curved palm from carpal bones.

Front 4

What are the categories of the manipulative prehension patterns

Back 4

1. palmar pinch - 1st digit to 2nd or 3rd digit (pad to pad touch)
2. lateral pinch - 1st digit palm is approximating the proxima phalynx of the 2nd digit
3. tip to tip: tips of the digits are opposing

**most common is palmar for picking up things and for holding things

Front 5

For digits 2 to 5, what phalynxes do you have? how about digit 1?

Back 5

2-5: proximal, distal, and middle
1- only proximal and distal

Front 6

1. carpometracarpal joint (CMC)
2. metacarpophalangeal (MCP or MP)
3. proximal interphalangeal (PIP)
4. Distal interphalangeal (DIP)

Back 6

1. base of palm: thumb is saddle joint and digits are gliding joint
2. thumb is a simple hinge joint
digits - ab/aduction, condyloid biaxial joints
3. IP hinge joint of thumb (not proximal or distal since there's only 1)
still hinge for all other digits
3. DIP joint only for digits, and its a hinge joint

Front 7

Movement of digits 2-5
1) joints involving flex/extension
2) abduction/adduction

Back 7

1) MP, PIP, DIP
2) MP joints (ab = moving away from 3rd digits, ad = moving toward 3rd digit)

Front 8

Movements of the thumb
1) adduction and abduction
2) flexion extension
3) opposition

Back 8

1) perpendicular to plane of palm; at CMC joint
2) at CMC/MP/IP; parallel to plane of palm
3) bring thumb over to 5th digit; at CMC

Front 9

Accessory structures
1) collateral ligaments
2) palmar ligament/ plate

Back 9

1) on either side of the joints, prevents deviation on the opposite direction
2) prevents hyperextension;

Front 10

Extrinsive digit flexors - begin in forearm and send long tendons into the hand
what type is responsble for manipulative and non manipulative?

Back 10

extrinsic - non manipulative prehension
intristinc - manipulative prehension patterns

Front 11

Flexor Digitorum Superficialis

Back 11

Extrinsic digit flexor

Flexor Digitorum Superficialis
Attachments:
Medial epicondyle of humerus Base of middle phalanx Action: Flex PIP joint
Innervation: Median nerve

Front 12

Flexor Digitorum Profundus

Back 12

Attachments:
Proximal ulna Base of distal phalanx Action: Flex DIP joint Innervation:
Medial part : ulnar nerve Lateral part: anterior Interosseous nerve
(from median)

Front 13

Describe the 2 portions of the flexor sheath

Back 13

1) membranous portion - promotes tendon gliding
2) retinacular portion - forms pulleys which stabilize the tendon

Front 14

What happens when the flexor sheath detaches?

Back 14

You have a bowstring phenomenon. The tendon bowstrings and its less efficient.

Front 15

Extensor digitorum

Back 15

Attachments:
Lateral epicondyle Extensor expansion Action: Extends MP ( also IPs) Innervation:
Radial nerve

Front 16

Extensor expansion

Back 16

The extensor mechanism is an elaboration of the extensor digitorum (ED) tendon on the dorsum of each phalanx.
•Non-contractile
•When ED contracts, the hood is pulled proximally and extends the IP joints

Front 17

Extrinsic of thumb
1) extensor polliic longus
2) extensor pollicis brevis
3) abductor pllicis longus
4) flexor pollicis longus

Back 17

1) extensds IP
2) extends MP and CMC of thumb
both innervated by radial nervel
3) abducts thumba at CMC ; radial nerve
4) flexes IP of thumb; median nerve

Front 18

Instrinsic hand muscls

Back 18

1) thenar compartmetn - thumb side; median nerve
2) hypothenar - ulnar nerve
3) adductor ulnar
4) central median and ulnar nerve

Front 19

What are the lumbricals of the central comparment?

Back 19

Attach at FDP tendon and extensor hood.
-fcn: flex MP, extend to PIP/DIP

innervation: median and ulnar nerve. lumbricals 1 2, = median
lumbricals 3, 4 = ulnar nerve

Front 20

What are the dorsal and palmar interossei msucles of the central compartment

Back 20

Attachments: Metacarpals to proximal phalanx and ext. exp.
Dorsal - 4 muscles - ABduction - Ulnar N.
Palmar - 3 muscles - ADduction - Ulnar N.

3rd digit asctually adducts in 2 directions.

Front 21

what is the prehension: power grip?

Back 21

-palmar grasph that refers to forcible motions of digits acting against the palm; fingers wrapped around object w/ counterpressure from thumb

invovles: long extrinsic finger flexors
• intrinsic muscles of the digits
• extensors of the wrist
• Extension of the of the wrist increases the distance over which the flexors of the fingers act, producing a stronger grasp
• Conversely, as flexion increases at the wrist, the grip becomes weaker and more insecure.

Front 22

Ulnar nerve provides what to the hand?

Back 22

Sensation to front and back of 5th digit and 1/2 of 4th digit

Front 23

What does the median nerve?

Back 23

Rest of the palm of the hand, in addition to what the ulnar nerve innervates.

Front 24

What does the radial nerve innervate for the hand?

Back 24

The back of the hand, aside from what ulnar nerve innervates

Front 25

What does the palmar cutaneous branch of the median nerve innervate?

Back 25

This goes above the carpal bone, while all the other median nerve branches go under the carpal bone.

Front 26

Radial nerve injury in the arm?

Back 26

Its in the triangular interval btween the long and lateral head of the triceps. Very posterior nerve, and travels right next to the humerus.

-Can occur if you have a mid humerus fracture.
-can occur if you have compression to the humerus. Primary is for extension, so if you take out all extensors (triceps, brachioradialis, aconeus), you get a wrist drop - no extension of wrist, or digits.

Front 27

Median nerve injury at wrist

Back 27

innervates some anteior forrearm mucles and some of the hand.

-forearm isnt effected
-intrinsics of hand will be effected. (thenar compartment)

can find Carpal Tunnel Syndrome - thenar wasting or atrophy
-wouldn't lose sensation in the middle part of the palm ( this is innervated by palmar cutaenous nerve that goes above the carpal bone)

Front 28

What is Carpal Tunnel?

Back 28

•Tendons of the FDS, FDP, FPL and the main branch of the median nerve pass through the carpal tunnel.
•The ulnar nerve and artery do not pass through the carpal tunnel
•There is one branch of the median nerve - the palmar cutaneous branch- that does not pass through the tunnel ( see cutaneous innervation notes)

Front 29

What is likely to cause ulnar nerve injury?

Back 29

Anything that hits externally. Falling, laceration, trauma.

Front 30

What's the cause and symptoms of Carpal tunnel syndrome?

Back 30

• Compression of median nerve in carpal tunnel
• Symptoms:
– decreased sensation
– pain/parasthesias
– decreased strength/coordination
– thenar atrophy

Front 31

What is De Quervain's tensosynovitis

Back 31

• Inflammation of extensor pollicis brevis and abductor pollicis longus tendons as they glide over radial styoid process
• Symptoms:
– Pain and swelling over radial styloid