Final Exam- Elbow and Wrist Flashcards
Bones in the Elbow Joint
Humerus
Ulna
Radius
Elbow Joint
A very stable joint that assists shoulder in application of force and controlling placement of hand in space
Assymetrical structure of trochlea creates angulation of ulna when extended known as the carrying angle
Elbow ROM
Flexion/Extension
-145 degrees active, 160 degrees passive. need 100-140 degrees to perform ADLs
Supination/Pronation
-85 degrees supination; 70 degrees pronation. need 50 degrees supination and 50 degrees pronation to perform ADLs.
Name the elbow flexors
ANTERIOR SIDE
- Biceps Brachii
- Brachioradialis
- Brachialis
Flexors are almost twice as strong as the extensors making us better pullers than pushers
Biceps Brachii
Mutliarticular muscle whose effectiveness is dependent on position of shoulder and radioulnar joints. Performs at 3 joints
Not effective when pronated.
MOST PROMINENT
Brachioradialis
used more in rapid movements or against resistance
Brachialis
Brachialis is the most effective elbow flexor.
Name the elbow extensors
- Triceps Brachii
2. Anconeus
Triceps Brachii
teacher response
Anconeus
teacher response
Biceps Brachii Action
Elbow flexion
Proximal radioulnar supination
Shoulder flexion
Brachioradialis
Elbow flexion
Some pronation and supination
Brachialis
Elbow flexion
Triceps Brachii
Elbow extension
Shoulder adduction
Shoulder extension
Anconeus
Elbow extension
Radio Ulnar Joints
SUPINATOR-always active
BICEPS BRACHII-active in rapid mvmts or against large loads
PRONATOR TERES-active in rapid mvmts or against large loads
PRONATOR QUAD-always active
Supinator
Supination of the proximal radioulnar joint
Pronator teres
Pronation of the proximal radioulnar joint
Pronator Quadratus
Pronation of the proximal radioulnar joint
Medial Epicondylitis
linked to movements containing high velocity valgus extension mechanism
large valgus torque near maximal external rotation resisted by a large varus torque generated by the soft tissue in the elbow.
Little Leaguer’s Elbow
Medial Epicondylitis
- medial strain imparted during the initial forward phase of throw as hand and elbow lag behind trunk and shoulder
- curveball pitching will magnify this medial strain throughout pitch and therefore is not recommended for young pitchers
Medial Elbow Injuries (Little Leaguers Elbow)
Sprain or rupture of ulnar collateral ligaments
Medial epicondylitis
Tendonitis of wrist flexors
Avulsion fractures of medial epicondyle
Osteochondritis dissecans to the capitulum (a lesion in the bone and articular cartilage) where the radial head is pushed up into the capitulum due to the compressive load developed from the valgus force
Tennis Elbow
-Lateral Epicondylitis- inflammation/ microdamage to tissues on the lateral side of the humerus, 30%-40% of tennis players will develop some amount of this injury
- cause include poor technique and equipment
e. g. off center shots and rackets strung too tightly
-the pain is exacerbated by activities involving EXTENSION of the wrist. These include lifting a suitcase, shaking hands, turning doorknobs, etc.
The Wrist and Hand
Wrist- radiocarpal joint condyloid joint
ulna makes no contact with carpals but floats on disc so it does not influence wrist movement during supination/ pronation
Midcarpal Joint
Radiocarpal joint is the articulate between the scaphoid and radius
The scaphoid may be one of the most important carpals because it supports the weight of the arm and transmits the forces between the hand and the forearm
Wrist ROM
flexion: 70-90 degrees need 10-15 for ADL’s
extension: 70-80 degrees need 35 degrees for ADL’s
ROM reduced when fingers are flexed
Radial Ulnar Deviation
proximal row of carpals glides over distal row
ROM
radial dev. 15-20 degrees
ulnar dev. 30-40 degrees
Carpometacarpal (CMC) Joint
CMC of thumb is a saddle joint that allows flexion/extension, ab-/adduction and rotation
these movement permit thumb to touch each finger (known as opposition)
opposition is very important in all gripping and prehension tasks
concave transverse arch metacarpals to facilitate gripping
Metacarpophalangeal (MCP) Joint
MCP of thumb is a hinge joint allowing only flexion and extension
MCP of fingers is a condyloid joint perming flex/ext and ab-/adduction
Wrist Extensors
Extensor Carpi Radialis Longus
Extensor Carpi Radialis Brevis
Extensor Digitorium
Extensor Carpi Ulnaris
Origin on lateral epicondyle
Because the extensors act on the elbow joint, elbow joint position will influence extensor output
Wrist Flexors
Flexor Carpi Radialis
Palmaris Longus (Absent in 13% of population)
Flexor Carpi Ulnaris
All fusiform muscles.
Origin on medial epicondyle
Flexor Carpi Ulnaris
strongest flexor
strength increased by encasing the pisiform in its tendon such that it becomes a seasmoid bone that improves the mechanical advantage of the muscle
Radial Deviation is created by_______.
Radial deviation is created by the radial muscles
Flexor carpi radialis
Extensor carpi radialis longus and brevis
Ulnar Deviation is created by______.
Ulnar deviation is created by the ulnar muscles
Extensor carpi ulnaris
Flexor carpi ulnaris
