Elbow MSK Flashcards
Brachialis
C5,6, upper trunk, lateral cord, musculocutaneous nerve
brachioradialis
C5,6, upper trunk, posterior cord, radial nerve (below spiral groove)
Pronator teres
C6,7, upper and middle trunks, lateral cord, median nerve
biceps brachii
C5,6, upper trunk, lateral cord, musculocutaenous nerve
triceps
C6,7,8 , all three trunks, posterior cord, radial nerve (innervated above the spiral groove)
Anconeous
C6,7,8, all three trunks, posterior cord, radial nerve (innervated above spiral groove)
Supinator
C5,6 upper trunk, posterior cord, radial nerve, PIN
Pronator teres
C6,7 , upper and middle trunks, lateral cord, median nerve
Pronator quadratus
C7,8,T1, middle and lower trunks, medial and lateral cords, median nerve, AIN
FCR
C6,7, upper and middle trunks, lateral cord, median nerve
FCU
C8,T1 lower trunk, medial cord, ulnar nerve
FDS
C7,8, middle and lower trunks, medial and lateral cords, median nerve
FDP
C7,8T1, middle and lower trunks, medial cord, AIN/ulnar nerve ..so profound that it requires 2 nerves to innervate it
flexor pollicis longus
C8, T1, medial and lateral cords, median nerve
osteochondrosis of the elbow
asepitc necrosis of capitellum epiphysis due to poor blood supply
osteochondritis dessicans
traction apophysitis of medial epicondyle growth plate
Nursemaids elbow
radial head subluxes out of place due to being yanked out of annular ligament; tx reduce it by hyper pronating or supinating while flexing
Ulnar collateral ligament sprain
medial elbow pain from excessive valgus stress (ANTERIOR BUNDLE of UCL), physical exam to look for increased laxity, surgery Tommy John if PT fails
Radial/Lateral collateral ligament sprain
excess varus force causing lateral elbow pain, worse with VARUS stress testing, RICe, PT, Surgery
Lateral epicondylitis
ECRB
Cozen test
pain palpating proximal common extensor tendon with resisted extension (using tendon rather than stretching it)
Mills test
pain while extending elbow, flexing and radially deviating the wrist (stretch it)
Tennis racket adjustment for tx of tennis elbow
increase grip size, decrease string tension to below 55 lbs, play on a slow court (ie clay), correct technique
Distal biceps tear
from lifting something very heavy, Hook test, surgery
Strongest restraint to valgus stress in the elbow
Anterior bundle of medial collateral ligament.
The medial (ulnar) collateral ligament (also known as the Tommy John ligament due to rupture in throwing athletes) is the primary restraint due to valgus force. Specifically, the anterior oblique band is loose in flexion and taut in extension
Shoulder abduction relief sign
Bakody sign
shoulder abduction relief sign or Bakody sign. Individuals with pathology at C5-6 feel relief of their symptoms in this position, which is thought to be due to decreased traction on the C5, C6 nerve roots.
Normal Shober test distance
The distance between the 2 points with forward flexion should exceed 15cm in non-affected individuals.
Differential for lateral epicondylitis
Patients whose symptoms are consistent with lateral epicondylitis/epicondylosis or “tennis elbow” but who do not respond to conservative treatments should be considered to have a posterior interosseous neuropathy. Mild neural compression of the posterior interosseous nerve may present with proximal and dorsal forearm pain without obvious muscle weakness, wasting, or sensory deficits.
A paramedian disc herniation in the lumbar spine has potential to affect the ** nerve roots
traversing
Injury to triangular fibrocartilage complex TFCC presentation and work up
This structure is a stabilizer of the distal radioulnar joint and is composed of an avascular articular disc and radioulnar ligament complex. It is often injured with repetitive wrist activities or compressive loads. TFCC tears are best imaged by magnetic resonance imaging (MRI).
Ulnar compression at cubital tunnel vs guyons canal
Sensory loss in the 4th-5th digits and along the dorsum of the hand implies an ulnar nerve injury with involvement of the dorsal ulnar cutaneous nerve (DUC). Lesions involving the DUC must be proximal to the wrist and Guyon canal because the DUC branches from the main trunk of the ulnar nerve 5-10cm proximal to the wrist.
Panner’s disease
Panner’s disease is usually seen in young boys aged 5 to 12 years. It is felt to be due to an interruption in the blood supply to the epiphysis resulting in initial resorption followed by eventual remodeling of the epiphysis. This condition most commonly occurs in the dominant arm and is found to be due to chronic repetitive trauma, hereditary factors, and certain endocrine disorders.
+ fat pad sign mechanism of injury
An elbow hyperextension injury is the most common mechanism of an elbow fracture resulting in a positive fat pad sign on x-ray.
