Upper Extremity MSK Flashcards
4 structures that can compress the median nerve at the elbow?
- Ligament of struthers
- Lacertus fibrosus
- Pronator teres
- FDS (between the two heads)
AC Joint Separation Types and Tx
- Type 1: partial AC tear, intact CC - > rehab with return in 2 wk
- Type 2: complete AC tear, intact CC -> rehab with return in 6 wk
- Type 3: complete AC and CC tear with clavicle floating upwards - > consider surgery
- Type 4: complete AC and CC tear with clavicle floating up and back -> need surgery
- Type 5: complete AC and CC tear with clavicle super up and back -> need surgery
- Type 6: complete AC and CC tear with clavicle floating down -> need surgery
Anatomic Snuffbox borders
- lateral: APL, EPB
- medial: EPL
Atraumatic shoulder dislocation management
AMBRI A: Atraumatic M: Multidirectional B: Bilateral R: Rehab I: Inferior capsule shift if they require surgery
Bankart lesion
Anterior labral tear that allows the humeral head to slip anteriorly
Bennett’s fracture
Oblique fracture at the base of the thumb metacarpal
Bone deviations seen in RA at the wrist/hand?
- Ulnar deviation of the MCPs
- Radial deviation of the wrist
- Dorsal subluxation of the ulna
Borders and contents of quadrangular space
- Borders: humerus, triceps long head, teres minor, teres major
- Contents: Axillary nerve and posterior humeral circumflex artery
Borders and contents of triangular interval
- borders: humerus, triceps long head, teres major
- contents: radial nerve profunda brachii artery
Borders and contents of triangular space
- borders: teres minor, teres major, long head of tricpes (lateral)
- contents: scapular circumflex artery
Boutonniere deformity cause
Tearing of the extensor hood at the PIP
Boxer’s Fracture
5th metacarpal fracture
Brachial artery course
enters in cubital fossa and divides into radial and ulnar arteries
Carpal bones
Carpal Tunnel structures and borders
4 FDS tendons, 4 FDP tendons, FPL tendon, median nerve bordered by scaphoid and pisiform
Five changes seen on X-ray in osteoarthritis
- Irregular joint surfaces
- Joint space narrowing
- Subchondral sclerosis
- Osteophytes
- Cystic changes
Colles Fracture
Distal radius fragment is dorsally displaced (CD). Associated with triangular fibrocartilage complex (TFCC) tears.
Common causes of hook of the hamate fractures?
direct trauma or forceful twisting of the wrist (racquet-related sports)
Cozen test
pain with palpation of common extensor tendon with resisted wrist extension (A)
Cubital fossa boundaries
- lateral: brachioradialis
- medial: pronator teres
- base: line through epicondyles
Deep forearm extensors
Supinator, APL, EPL, EPB, EIP
DeQuervain’s Tenosynovitis
inflammation of APL and EPB tendon due to overuse
Dorsal Compartments of the Wrist
1: APL, EPB 2: ECRL, ECRB 3: EPL 4: EDC, EIP 5: EDM 6: ECU
Forearm flexor layers
- Superficial: (lateral to medial) pronator teres, flexor carpi radials, palmaris longus, flexor carpi ulnaris
- Intermediate layer: flexor pollicis longus, flexor digitorum superficialis, flexor digitorum profundus
- Deep layer: pronator quadratus
Four fingers as forearm flexors
PRLU
Four tests for anterior glenohumeral instability
- Apprehension
- Relocation
- Anterior drawer
- Anterior load-and-shift
Four tests for posterior glenohumberal instability
- Jerk
- Kim
- Posterior drawer
- Posterior load-and-shift
Function of Superior Glenohumeral ligament
prevent inferior translation of the humerus
function of the inferior glenohumeral ligament
prevent anterior translation of the humerus above 90 degrees
function of the middle glenohumeral ligament
prevent anterior translation of the humerus
Fusion position for elbow arthrodesis?
- Unilateral: flexion to 90 degrees
- Bilateral: flexion to 65 degrees for one arm and 110 degrees for the other
Heberden nodes
DIP appears swollen due to osteophytes
Hill-Sachs lesion
Posterolateral humeral head compression fracture due to abutment of the rim of glenoid fossa, associted with anterior dislocations. Involvement of more than 30% of the articular surface may cause instability.
How to reduce a Nursemaid Elbow
Hyperpronate or supinate while flexing at the elbow
How to test subscapularis strength
lift off test
humeral stress fx presentation and treatment
- shoulder pain worse with throwing
- limit activity for 8 - 12 weeks, gradual return
Indication for MRI arthrogram over gold standard MRI when assessing for RTC injury?
suspect labral tear
Indications for surgical treatment of clavical fracture
- open fx
- grossly displaced with skin tenting
- lateral fracture with more than 1cm displacement at AC joint
Jerk test
- Test for posterior shoulder instability
- Flex arm to 90, internal rotate, adduct across and push humerus posteriorly. Pt. will jerk away if positive.
Jersey finger
Injury to FDP tendon
Kienbock disease
osteonecrosis of the lunate 2/2 to AVN seen in patients with a short ulna
Kim test
- test for posterior instability
- similar to “jerk” test however you simply flex the arm up and apply a posteroinferior force.
Labral Tear Test
O’Brien: Hold arm out and slightly adducted. Positive test more painful with resistance with palm down than palm up.
Lateral Scapular Winging
Trapezius weakness 2/2 to nerve injury in posterior triangle of the neck
Little Leaguer’s Elbow
Medial epicondyle apophysisits secondary to repetitive valgus stress with throwing. Can lead to osteochondritis dissecans of the capitellum (localized fragmentation of bone and cartilage).
Medial Scapular Winging
Serratus Anterior weakness secondary to bench pressing heavy weights or wearing heavy pack straps
Mill’s test
pain with elbow extension and wrist flexion/radial deviation (B)
Modifications made to tennis racket in patient with lateral epicondylitis (2) ?
decrease string tension and increase grip size
Most common cause of shoulder pain
Impingement syndrome
most common direction and cause of shoulder instability
anterior and inferior instability in younger people with repeated arm abduction and external rotation (volleyball players, pitchers)
Most common joint dislocated in children?
elbow
Most common location for clavicle fracture
middle third
Most common presentation of shoulder impingement syndrome?
Pain with repetitive overhead activities, occurs during “catch” phase of swimming when the hand enters the water.
most common site for biceps tendonopathy
proximal long head (inserts on supraglenoid tuberosity)
Most common site for humeral fracture? How does this affect abduction?
surgical neck, supraspinatus causes abduction of proximal fragment
most common site of stenosing tenosynovitis
A1 pulley (MCP
muscle most commonly involved in lateral epicondylitis?
ECRB
Muscles in the hand not innervated by ulnar nerve
median: LOAF muscles
Name 5 scapular stabilizers
- Trapezius
- Rhomboids
- Levator Scapulae
- Serratus Anterior
- Latissimus Dorsi
nerve and artery damaged with humeral midshaft fracture
radial nerve, profunda brachii artery
nerve and artery damaged with humeral supracondylar fracture
median nerve, brachial artery
Nerve and artery damaged with humeral surgical neck fracture
axillary nerve, posterior circumflex artery
Nerve damaged in olecranon fracture
Ulnar
Osteochondrosis of the Elbow (Panner’s Disease)
Aseptic necrosis of the capitellum epiphysis due to poor blood supply. Lateral elbow pain in children worse with activity.
Posteromedial elbow pain with pitching
Valgus Extension Overload Syndrome (olecranon osteophytosis and loose body formation secondary to repetitive abutment of the olecranon against the olecranon fossa)
Range of motion lost first with frozen shoulder
abduction and external rotation
Relationship between glenohumeral and scapulothoracic joint motion
2 degrees of GH for 1 degree of ST motion (120 deg of GH to 60 deg of ST)
Risk factors for Dupuytren Contracture
Older male with alcoholism, seizures, and diabetes
Rolando’s fracture
comminuted, “T”, or “Y” fracture at the base of the thumb metacarpal
RTC/Impingment Tear Tests (3)
Empty Can, Neer, Hawkins
scaphoid fx treatment
- long thumb spica cast x 6 weeks with wrist in neutral position
- Can transition to short thumb spica at 6wk if proper healing
- surgery if fracture is displaced > 1mm, involves the proximal pole, or delayed presentation
Scaphoid site at risk for AVN
Proximal 1/3
significance of Lister’s tubercle
seperates 2nd and 3rd dorsal compartments of the wrist
Skier’s Thumb
1st digit UCL tear at distal insertion
Tx: thumb spica splint
Smith Fracture
Distal radius fragment is volarly displaced (Sweater Vest)
sport specific recommendations for tennis elbow
larger grip and decrease string tension to < 55 lbs
Stages of frozen shoulder
- painful: 8 months
- stiffening: 8 months
- thawing: 8 months
Stener’s lesion
Trapping of thumb adductor aponeurosis in the MCP joint due to severe 1st digit UCL tear
strongest elbow flexor muscle
brachialis
strongest forarm supinator muscle
biceps
Swan neck deformity cause
synovitis
Test used to detect SLAP lesions
O’Brien’s : Arm internally rotated, forward flexed, and adducted 15 degrees. Pain with resisted downward force that improves with hand supination.
Testing FDS and FDP
three joints of the elbow
- radiocapitellar
- ulnotrochlear
- radioulnar
Traumatic shoulder dislocation management
TUBS T: Traumatic U: Unidirectional B: Bankart lesions S: Surgery
Treatment for a clavical fracture
- reduce and sling for 3-6 weeeks followed by ROM and PT
- surgery if very displaced or open fx
Treatment for a humerus fracture
- One part (Displaced less than 2 cm): sling x 6 weeks followed by PT
- 2-4 part: Surgery
Trigger finger
Tenosynovitis at the A1 pulley
Valgus extension overload provocative test?
Flex elbow to 30 degrees, repeatedly extend elbow while applying a valgus stress. Positive if pain towards end of extension.
What can be seen on X-ray with injury to the elbow’s ulnar collateral ligament?
- 2mm joint space with stress view
- calcification and spurring along UCL
What is the fusion position in shoulder arthrodesis?
- 30 degrees flexion
- 50 degrees abduction
- 50 degrees internal rotation
What is the maximum amount of shoulder abduction with the humerus interally rotated? Why?
120 degrees, due to greater tuberosity being forced under the acromion
what part of the elbow ulnar collateral ligament is most commonly sprained?
anterior bundle
What three structures are commonly involved in shoulder impingement syndrome?
- subacromial bursa
- biceps tendon
- supraspinatus tendon
Where is supraspinatus prone to injury
1 cm from insertion in area of hypovascularity
Which forearm bone articulates with the capitulum?
radius
X-ray findings of chronic rotator cuff tear
- superior migration of the humerus
- flattening of the greater tuberosity
- subacromial sclerosis and severe superior medial wear
X-ray view used for Bankart lesions
West Point Axillary
X-ray view used for Hill-Sachs lesions
Stryker notch
Yergason’s test
Pain at the anterior shoulder with resisted supination
