Elbow & Forearm Flashcards
What is the look component of the elbow exam?
Carrying angle
- male: 5-10 degrees
- female: 10-15 degrees
Fixed flexion deformity
Skin: scars, bruising, sinuses, swellings
Rashes: psoriatic plaques, rheumatoid nodules
Wasting
What is the feel component of the elbow exam?
Skin = temperature, effusions/swellings e.g. olecranon bursitis
Bony landmarks = olecranon tip, medial epicondyle, lateral epicondyle, radial head
Tendons = common extensor origin (just distal to lateral epicondyle), common flexor origin (just distal to medial epicondyle)
What is the move component of the elbow exam?
Flexion (150 degrees)
Extension (0 degrees)
Pronation (70 degrees) = while elbow flexed to 90 degrees
Supination (80 degrees) = while elbow flexed to 90 degrees
What are the special tests of the elbow exam?
Lateral collateral ligament = flex elbow to 30 degrees and apply varus force whilst forearm supinated
Medial collateral ligament = flex elbow to 30 degrees and apply valgus force whilst forearm pronated
Tennis elbow = with forearm pronated and wrist fully flexed, ask patient to extend wrist whilst applying resistance
Golfer’s elbow = with forearm pronated and wrist fully extended, ask patient to flex wrist whilst applying resistance
Posterolateral rotary instability = with patient supine, flex the elbow and shoulder to 90 degrees and fully supinate wrist, then extend elbow and flex shoulder whilst applying valgus force and axial compression —> subluxation of radial head
Describe some common presentations of elbow disorders.
Lateral epicondylitis (tennis elbow) = pain on resisted wrist extension, worsens with use of extensor muscles (Mx = splints, NSAIDs, steroid injections, surgery)
Medial epicondylitis (golfer’s elbow) = pain on resisted wrist flexion, worsens with use of flexor muscles (Mx = see above)
Posterior interosseous nerve compression
Referred pain
Locking (loose bodies - OA)
Stiff elbow:
- OA
- RA
Olecranon bursitis
Cubital tunnel syndrome (ulnar nerve entrapment)
What is the result of a lesion at the elbow affecting the median nerve e.g. supracondylar fracture?
Paralysis of flexors and supinators supplied by median nerve —> forearm constantly supinated, weak flexion, adduction
Paralysis of flexor pollicis longus and brevis —> thumb cannot flex
Paralysis of radial two lumbricals —> cannot flex at MCP or extend at IP of index and middle fingers
Wasted thenar eminence
= hand of Benediction (when trying to make a fist, can only flex little and ring fingers)
What is the result of a lesion at the elbow affecting the ulnar nerve e.g. fracture of medial epicondyle?
Loss of sensation of all branches
Paralysis of flexor carpi ulnaris and ulnar half of flexor digitorum profundus —> when wrist is flexed, it also abducts
Paralysis of interossei —> fingers cannot abduct or adduct
Paralysis of ulnar two lumbricals —> cannot flex at MCP or extend at IP joints
No ulnar claw
What is the result of a lesion at the elbow affecting the radial nerve in the radial groove e.g. humeral shaft fracture?
Superficial branch damaged —> loss of sensation on dorsal surface, thumb, and radial two and a half digits
Weakened triceps brachii, paralysis of muscles in pos. compartment —> unable to extend the wrist and fingers —> unopposed wrist flexion —> wrist drop
What is the result of a lesion at the elbow affecting the deep branch of the radial nerve e.g. radial head fracture?
No sensory function lost
All muscles in pos. compartment except supinator and extensor carpi radialis longus —> extension can still occur
What is the result of a lesion at the elbow affecting the superficial branch branch of the radial nerve?
Sensory loss of dorsum, thumb, and radial two and a half digits
No motor function lost
Contrast Monteggia’s and Galeazzi’s fractures.
Monteggia’s: ant. dislocation of radial head and fractue of prox. ulnar with ant. angulation
Galeazzi’s: fracture of distal radius with dislocation of distal radioulnar joint
What is the 22-11-11 rule of the radius?
Radial inclination (angle between long axis of radius and line along articular surface of radius) should be 22 degrees +/- 2 degrees
Radial length (distance between tangents of radial styloid and ulnar head) should be 11mm +/-2mm
Radialt tilt (angle between articular surface of radius and radial shaft) should be 11 degrees +/- 2 degrees
What is the sail sign on the elbow?
Elevation of ant. fat pad to create sail silhouette, indicates presence of elbow joint effusion (inflamed synovial membrane forces fat pad into olecranon)
note: cannot normally see pos. fat pad, therefore presence indicates humeral or radial head fracture or distal radius (Stener’s injury)
