Elbow, Radioulnar and Hand joint Flashcards
what 3 joints does the elbow complex include
the humero-radial joint
the humero-ulnar joint
the proximal radial ulnar joint
all of these joints are surrounded by the same capsule
what two joints are considered the common elbow joint?
the humero-radial joint
the humero-ulnar joint
what impression is on the head of the radius
the fovea
where is the axis of motion of the elbow complex?
approximately on humans slightly distal to the epicondyles of the humerus
- more oblique than horizontal
what is the carrying angle of the elbow complex?
varies from 5-19 degrees
more in women than men
When your arms are held out at your sides and your palms are facing forward your forearm and hands should normally point about 5 to 15 degrees away from your body. This is the normal “carrying angle” of the elbow.
what is the purpose of the carrying angle?
This angle allows your forearms to clear your hips when you swing your arms, such as during walking or other activities. It is also important when carrying objects. Certain fractures of the elbow can increase the carrying angle of the elbow, causing the arms to stick out too much from the body.
what is cubitus varus
It occurs in only the extension type of supracondylar fracture of the humerus, causing a reduction or loss of the carrying angle
what is cubitus valgus
a deformity in which the forearm is angled out away from the body when the arm is fully extended
what are the 4 ligaments at the elbow joint?
Medial collateral ligament. Located on the inside of the elbow this ligament connects the ulna to the humerus.
Lateral collateral ligament. Located on the outside of the elbow this ligament connects the radius to the humerus.
Annular ligament
Quadrate ligament.
what type of ligaments are found at the elbow joint
intrinsic ligaments
Mnemonic: 3 B’s bend the elbow? What causes extension? Which small muscle also helps the elbow flex?
Flexion - Biceps brachii, Brachialis, Brachioradialis muscles
Extension - Triceps brachii muscle
- anconeus also helps elbow flex
The ________ head of the Triceps brachii is the strong of the three heads
Lateral Triceps brachii
active ROM of motion for elbow flexion
145%
passive ROM of motion for elbow flexion
160%
elbow extension ROM
0%
hyperextension ROM
5-10%
the articular surface of the proximal (superior) radio-ulnar joint
Head of radius, radial fossa of ulna
ligaments of proximal (superior) radio-ulnar joint
Annular ligament - forms a ring (holds the head of the radius)
quadrate ligament
movements of the proximal (superior) radio-ulnar joint
supination and pronation
the articular surface of the distal (inferior) radio-ulnar joint
Distal head of ulna, the ulnar notch of the radius
what is a special feature of the distal (inferior) radio-ulnar joint
Triangular fibrocartilage complex: Articular disc of distal radioulnar joint
covered by hyaline cartilage
disc separation radio-ulnar joint to radial-carpal joint
supporting ligaments of the distal (inferior) radio-ulnar joint
dorsal and palmar radioulnar ligaments
which joint is between the shafts of the radius and ulna, united by an interosseous membrane.
the middle radioulnar joint
what type of joint is the middle radioulnar joint
a fibrous joint
- ampharthrosis: permitting only slight movement
what type of joint is the distal radioulnar joint
This joint is a synovial, uniaxial, pivot joint
what type of joint the proximal radioulnar joint
This joint is a synovial, uniaxial, pivot joint.
all synovial joints are
diarthrosis
what is protonation ROM
80 degrees
what is the main supinator of the radio-ulnar joint? What is the supination of ROM?
biceps brachii
90%
Why does the triceps brachii contract when you squeeze your first maximally?
To stabilize the elbow (not waste energy in elbow movement)
To stabilize the proximal attachments of the finger and wrist muscles
Contraction in both the elbow flexors and the triceps brachii with a tension roughly proportionate to the amount of force produced at the fist
the articular complex of the wrist (wrist complex) (3)
The radio-carpal joint
The mid-carpal joint
Intercarpal joints
what is usually known as just the wrist joint?
radio-carpal joint
The ligaments of the radio-carpal joint are arranged in two groups:
The collateral ligaments
The anterior and posterior ligaments
a synovial planar (plane) joint between the proximal and distal rows of carpal bones (except pisiform).
The mid-carpal joint
a group of small synovial planar joints between the proximal or distal carpal bones.
Intercarpal joints
what are the two collateral ligaments of the wrist joint
- ulnar collateral ligament
- radial collateral ligament
the _______ ligament expansions from the radius to the pisiform bone;
Palmar (anterior) radio-carpal ligament
movements of the radio-carpal joint
Flexion, extension, adduction and abduction
when is the radial collateral ligament stretched?
adduction
when is the ulnar collateral ligament stretched?
abduction
radial deviation ROM
15
- limited due to the styloid process of the radius
ulnar deviation ROM
30
In general, the range of abduction and adduction is minimal when the wrist is ________ or __________, because of the tension developed in carpal ligaments.
fully flexed or extended
Wrist Adduction and abduction is synergistic combination of
of the wrist flexors and
extensors result in adduction and abduction
Wrist Adduction: a combined effort by (2)
Flexor Carpi Ulnaris
Extensor Carpi Ulnaris
Wrist Abduction: a combined effort by (4)
Flexor Carpi Radialis
Extensor Carpi Radialis Longus
Extensor Carpi Radialis Brevis
Abductor Pollicis Longus
Wrist Flexion: a combined effort by (6)
Flexor Carpi Radialis
Flexor Carpi Ulnaris
Palmaris Longus
Flexor Digitorum Superficialis
Flexor Digitorum Profundus
Flexor Pollicis Longus
Wrist Extension: a combined effort by (8)
Extensor Carpi Radialis Longus
Extensor Carpi Radialis Brevis
Extensor Carpi Ulnaris
Extensor Digitorum
Extensor Digiti Minimi
Extensor Pollicis Longus
Extensor Pollicis Brevis
Extensor Indicis
what type of joint is Carpometacarpal Joint 1? What types of movement does it permit?
- synovial saddle joint
- flexion, extension, abduction and adduction
- a little bit of rotation during opposition
which CMC joints have the least amount of movement?
2nd and 3rd CMC (motion of 2 degrees or less)
axis of the hand passes through the 3rd
The ____ CMC joint has 10 to 15 of dorso-volar movement.
4th
MCP joint is what type of joint?
(Metacarpophalangeal)
Synovial, condyloid joint
what are the ligaments at the MCP joint?
collateral ligament and palmar ligament (aka palmar plate)
When the MCP joint is in 90 of flexion, the __________ are taut
collateral ligaments
