Unit 11: Hand Flashcards
How many bones are found in the hand?
27
What are the different categories of bone within the hand?
Carpals
Metacarpals
Phalanges (proximal, middle, distal)
What term is used to describe the yellow joints?
Interphalangeal articulations
What term is used to describe the green joints?
Metacarpophalangeal joints
What term is used to describe the red jonts?
Intercarpal articulations
What is the organisation of the carpal bones in the hand?
Proximal - 4 - articulate with forearm
Distal - 4 - articular with carpals
What are the different capate bones?
(way to remember)
So long to pink here comes the thumb (start at proximal under thumb and go in circle)
Scaphoid
Lunate
Triquetral
Pisiform
Hamate
Capitate
Trapezoid
Trapezium
Label the different carpal bones
Pink - scaphoid
Blue - lunate
Green - triquetrum
Red - pisiform
Blue - hamate
Yellow - capitate
Green - trapeziod
orange - trapezium
What is the clinical importance of the anatomical snuff box?
Is made by a gap between the outcropping ‘pollicis’ muscle of the extensor compartment of the forearm.
Contains the scaphoid bone - which is commonly injured when falling on an outstretched hand - can be palpated in this area - painful indicates injury.
Also contains the continuation of the radial artery
What are the different movements of the digits?
Do them?
Flexion /extension of the metacarpophalangeal joints and the interphalangeal joints
Abduction and adduction of the digits
What classification of muscles are responsible for which movements of the digits?
Extrinsic - flexion and extension
Intrinsic - flexion, extension, abduction and adduction
What are the different movements of the thumb?
Can you do them?
What are the extrinsic muscles of the hand?
Flexors for the digits and the thumb
Extensors for the digits and thumb
Abductor for the thumb
What are the intrinsic muscles groups of the hand?
Thenar muscles
Hypothenar muscles
Lumbricals
Interossei
Describe the location of the thenar muscles
Squidgy bit under the thumb
Describe the location of the hypothenar muscles
Squidgy bit under the little finger
What is the function of the hypothenar group?
Aids with grip
What muscles are found in the thenar group for intrinsic muscles of the hand?
Abductor pollicis brevis
Flexor policis brevis
Opponens pollicis
What innervates the thenar muscle groups?
Median nerve.
What prevents the tendons in the hand from rubbing together and causing pain?
Surrounded by synovial fluid
What is the function of the lumbrical intrinsic muscles of the hand?
Flexion of metocarpopharangeal and extension of the interphalangeal
Characteristis shape is demonstrated by holding a marble
Describe the location of the lumbricals intrinsic muscles of the hand
Originate on the palmar side - tendon of flexor digitorum profundus
Insert onto the dorsal side on the extensor hood.
This means is crosses the palmar side of the metacarpophalangeal joint but the dorsal side of the interphalangeal joints.
What is the function of the interossei muscles?
Abductors and Adductors of the digits (mainly may be small rudimentary associated with pollicis)
What is the function of the interossei muscles?
Dorsal interossei abduct (DAB)
Palmar interossei adduct (PAD)
Where are the interossei bones of the hand located?
Between the metacarpal joints
One set is found on the palmar surface there are 3 of these, and another set is found on the dorsal surface of which there are 4.
What innervates the intrinsic muscles of the hand?
Mainly ulnar
Except - median - for 1/2 loaf - 0.5 lumbricals and thenar (opponens pollics, abductor pollicis brevis, flexor pollicis brevis)
What are the hypothenar muscles of the hand?
Flexor digiti minimi brevis
Abductor digit minimi
Opponens digit minimi
Describe the cutaneous innervation of the hand?
Palmar surface - thumb to digit 3 is median,four and little finger is ulnar
Dorsal surface - 3.5 , four and little finger are ulnar, finger tips of 2 and 3 are median, and the 1,2,3.5 are radial
What is the motor innervation of the hand ?
All median
Except half loaf:
1/2 lumbricals, opponens digit minimi, flexor digiti minimi and abductor digit minimi which are ulnar nerve.
Describe the relevant positioning of the thenar muscles.
Most superficial
Abductor pollicis brevis
Flexor pollicis brevis
Opponens pollicis
Most deep
Describe the relevant positioning of the hypothenar muscles.
Most superficial
Palmaris brevis
Abductor digit minimi
Flexor digiti minimi
Opponens digiti minimi
Most deep
What is a good way to differentiate between lumbrical and interossei muscles on clinical imaging?
Lumbircal - originate from tendor (flexor digitorum profundis)
Interossei - originate from bone - metacarpal bones.
Name the muscle
Opponens pollicis
Name the muscle
Abductor pollicis brevis
Name the muscle
Flexor pollicis brevis
Name the muscle
Lumbricals
Name the muscles
Palmaris brevis
Name the muscle
Abductor digit minimi
Name the muscle
Flexor digiti minimi
Name the muscle
Opponens digiti minimi
Name the muscle
Dorsal interossei muscles
Name the muscle
Palmar interossei
What muscle is closely associated with the thenar muscles of the hands?
The adductor pollicis.
Is located in the thenar emis but is included as its own adductor compartment of the hand
What muscle is this?
The adductor pollicis
Identify the green and the grey tendons
What is the associated muscle?
Green - flexor digitorum superficialis
Grey - flexor digitorum profundis tendon
Muscle - lumbricals - originate from the flexor digitorum profundis tendons.
