Architecture of the hand Flashcards
Name the joints in the thumb from proximal to distal.
- Carpometacarpal joint CMC, 2.Metacarpophalangeal Joint (MP),
- Proximal Interphalangeal Joint (PIP
What kind of joint is the CMC joint of the thumb?
saddle joint
How many degrees of movement and what are the degrees of movement in the CMC joint of the thumb?
2 degrees of freedom:
Flexion/Extension
Abduction/Adduction
What supports the CMC joint?
radial, ulnar, volar, and dorsal ligaments stabilize joint capsule
thenar muscles stabilize thumb in all planes
What kind of joint is the metacarpophalangal joint (MP) of the thumb?
condyloid joint
How many degrees of freedom does the MP joint of the thumb have and what are they?
2 degrees of freedom:
Flexion/extension
Abduction/Adduction
Which stabilizing structures do all joints have in common?
- Cartilaginous Volar Plate
2. Ulnar and radial (lateral) collateral ligaments
What structures stabilize the MP joint of the thumb?
- Volar plate
- lateral collateral ligaments
- Medial and Lateral sesamoid bones
T/F For the MP joint, the volar plate is firmly attached to the volar side of the proximal phalanx and loosely attached to the volar side of the metacarpal.
True. This allows for for the thumb to smoothly glide into flexion and avoid hyperextension.
Which muscle is attached to the medial sesamoid bone on the thumb MP joint?
A. Adductor Pollicis Muscle
B. Abductor Pollicis
C. Flexor Pollicis Brevis
A. Adductor Pollicis Muscle
Which 2 muscles are attached to the lateral sesmoid bone of the thumb MP joint?
A. Adductor Pollicis Muscle
B. Abductor Pollicis
C. Flexor Pollicis Brevis
B. Abductor Pollicis
&
C. Flexor Pollicis Brevis
What type of joint is the PIP joint of the thumb? And how many Degrees of freedom does it have?
Hinge Joint
One degree of freedom:
Flexion/Extension
What 2 things stabilize the thumb’s PIP joint?
- Collateral ligaments
2. Volar Plate
List the joints of the digits from proximal to distal
- Metacarpophalangeal Joint (MP)
- Proximal Interphalangeal joint (PIP)
- Distal interphalangeal joing (DIP)
What kind of joint is the MP of the digit? How many degrees of freedom does it have?
Condyloid Joint
2 degrees of freedom
Flexion/Extension
Abduction/Adduction
What structures stabilize the MP joint of the digits?
- volar plate
- Collateral Ligaments
- Deep transverse metacarpal ligament
- A-1 Pulley— with the flexor tendons that go under it
- Sagittal band fibers of extensor hood
T/F The deep transverse metacarpal ligament is attached to adjacent metacarpals and border the volar plates
True
T/F The deep transverse metacarpal ligament stabilizes the metacarpals, but does not allow movement of one metacarpal to another.
False. It does stabilize the metacarpals, and prevent from hand bending backwards.
BUT it does allow some movement from one metacarpal to another
________- Flexor tendons run through tube like structures to stabilize movement and is located at the head of the metacarpal.
A-1 Pulley or Annular pulley
T/F Lateral and Medial sagittal bands begin at volar plate
True.
T/F Sagittal bands create the extensor hood, a cover for extensor mucles to run under.
True.
What kind of joints are PIP and DIP of digits?
What are the degrees of freedom and movments?
Hinge Joint.
1 degree of freedom
Flexion/Extension
What to structures stabilize the PIP and DIP joints?
- Volar Plate
2. Collateral Ligament
What structures are part of the central fixed unit of the hand?
(3 things)
Metacarpal two
Metacarpal three
Distal carpal row
What structures are part of the mobile units of the hand?
Thumb
Index finger
Metacarpals four and five and corresponding fingers
What use are the arches of the hand?
help us adapt our hands to the task to be performed
What are the three types of arches?
Transverse
Longitudinal
Oblique
Which arch is this? Opposition of each digit (in turn) to the thumb.
A. Longitudinal
B.Transverse
C. Oblique
C. Oblique
The most important oblique arch is the pointer finger to the thumb.
Which arch is this? It includes each digit and their metacarpal. The Keystone is the metacarpal head.
A. Longitudinal
B.Transverse
C. Oblique
A. Longitudinal
Which arch is this? There are two located at the carpals and the metacarpal heads.
A. Longitudinal
B.Transverse
C. Oblique
B. Transverse
There is the fixed transverse (carpal arch) and the mobile transverse (deep transverse arch)
_______ runs through the 3rd metacarpal bone and 3rd digit. Abduction and adduction occur in relation to this.
Axis of the hand
Which two arteries provide circulation to the hand?
radial and ulnar arteries
This nerve provides sensation to the 5th metacarpal and 5th digit and half of the 4th metal carpal and 4th digit on both sides of the hand.
A. Median nerve
B. Ulnar Nerve
C.Radial Nerve
B. Ulnar Nerve
This nerve provides sensation to metacarpals 1 2 and half of three on the palm side, their corresponding digits and the thumb. On the back of the hand it provides sensation to digits 1, 2 and half of three.
A. Median nerve
B. Ulnar Nerve
C.Radial Nerve
A.Median Nerve
This nerve provides sensation to the back of the thumb and metacarpals 1 and 2 on the dorsal surface of the hand. It provides very little of the palmar side.
A. Median nerve
B. Ulnar Nerve
C.Radial Nerve
C. Radial Nerve