L14: Examination Elbow 1 Flashcards
What are the 3 joints in the elbow (compound synovial joint complex)?
- Humeroulnar joint
- Radiohumeral joint
- Superior radio-ulnar joint
What are 4 characteristics of the humeroulnar joint?
- Articulation: trochlea of the humerus and trochlea notch of the ulna
- Stable bony arrangement
- Uni-axial hinge joint:
- Flexion/extension
- NB: Small amt of rotation and side to side motion due to asymmetry
- In the frontal plane, medial aspect of trochlea extends more distally than the lateral aspect
What is the close packed position and open packed postion humeroulnar joint?
- Close packed position
- extension and supination
- Open packed position
- 70º flexion, 10º supination
What is the carrying angle for the humeroulnar joint?
Accounts for carrying angle (valgus alignment)- In full extension and supination
- Female > male
- Between 10-15º in females
- Between 5-10º in males
Looking for a loss or excessive carrying angle
- Malunion (fracture)
What are 2 characteristics of the radiohueral joint?
- Articulation: capitellum (Ball shape) of the humerus and radial head (Cup shaped)
- Spherical joint
- Flexion/extension
- Pronation/supination
What is the close packed position and open packed postion radiohumeral joint?
- Close packed position
- 90º flexion, 5º supination
- Open packed position
- elbow extension, supination
What are 2 characteristics of the superior radioulnar joint?
- Articulation: convex rim of the radial head and concave radial notch of the ulna
- Pivot joint
- pronation/supination
- NB: Moves with the inferior RUJ
- With affect joint at the other end
What is the close packed position and open packed postion superior radioulnar joint?
- Close packed position
- 5º supination
- Open packed position
- 35º supination, 70º elbow flexion
What is flexion for the HUJ and RHJ?
- HUJ: ant glide of ulna on humerus
- RHJ: ant glide of radial head on capitellum
AP for radiohumeral and AP for humero-ulnar joint
What is extension for the HUJ and RHJ?
- HUJ: post glide of ulna on humerus
- RHJ: post glide of radial head on capitellum
What is pronation for the HUJ and RHJ?
- RHJ: med spin of radial head on capitellum
- Sup RUJ: posterior glide of radial head
AP glide
What is supination for the HUJ and RHJ?
- RHJ: lat spin of radial head on capitellum
- Sup RUJ: anterior glide of radial head
PA glide
What are the 5 characteristics of medial collateral ligament?
- 3 bundles – ant, post, transverse
- Resists valgus stress
- Anterior bundle 1º restraint
- taut through whole range
- Post bundle - taut at full flexion
- Transection of MCL: increased instability in pronation than supination during passive elbow flexion
What are the 5 characteristics of lateral collateral ligament?
- 3 bundles – radial collateral, accessory collateral, lateral UCL
- Resists varus stress
- LUCL (Below radial head) major contributor to prevention of posterolateral
- instability
- Uniform tension throughout range
- Transection of LCL: increased rotatory instability in supination than pronation during passive flexion
What are the 2 characteristics of annular ligament?
- surrounds neck of radius and attaches to radial notch of ulna
- Resists lateral subluxation and distal subluxation/dislocation
Often in children (grab on kids and pulling)
What are the 2 characteristics of interosseous membrane?
- Binds the radius to ulna
- Force transmission proximally through the upper limb
WB- force occurs at radiocarpal joint –> allow forces to be transmitted between ulnar and radius
What are 2 muscles in the anterior elbow?
- biceps- Shoulder flexion, elbow flexion and supination
- brachialis
What are 2 muscles in the posterior elbow?
- triceps
- anconeus
Elbow extension
What are 4 muscle group in the lateral elbow?
- Wrist E: ECRL, ECRB, ECU
- Finger E: ED, EDM- Common extensor tendon
- Supinator
- Elbow F: brachioradialis
Common extensor tendinopathy : tennis elbow
What are 3 muscle group in the medial elbow?
- Wrist F: FCR, FCU
- Finger F: PL
- Pronator teres
Common flexor tendinopathy (golfers elbow)
What are the 3 factors limiting normal elbow movements for flexion?
- soft tissue approximation anteriorly
- radial head and coronoid process opposition
- tension in posterior capsule, and triceps
What are the 2 factors limiting normal elbow movements for extension?
- olecranon opposition
- Tension in anterior capsule, ant portion of MCL, and the elbow flexors
What are the 2 factors limiting normal elbow movements for pronation and supination?
- Reciprocal stretch of antagonist muscles
- Quadrate ligament
What are 3 peripheral nerves in the elbow?
- Median
- Ulnar
- Radial
- Posterior interosseus (PIN)- Motor branch
- Superficial radial- Sensory branch
- Consider path and potential sites of compression
- Consider symptoms
- Mechanosensitivity
- Sensory / motor loss
What are 2 characteristics of the median nerve?
- at the elbow
- Cubital fossa = nerve medial to biceps tendon
- Innervates most flexors in forearm, thenar muscles in hand
What are 2 common sites of compression of the median nerve?
- Distal humerus under the ligament of Struthers
- Elbow joint between 2 heads of pronator teres