11 - Elbow

what are the 3 joints in the elbow?

humeroulnar, radioulnar, humeroradial

where is the humeroulnar joint? what is the angle of the humeral head?

between the trochlea of humerus and trochlear notch of ulna

posterior angle of 30-45º

what is the ulnar (medial) collateral ligament? when are the ulnar collateral ligaments tight?

runs obliquely

anterior fibers tight in extension, posterior fibers tight in flexion >90º

what is the radial (lateral) collateral ligament?

runs from the lateral epicondyle to the annular ligament, thickening of the capsule

what does the annular ligament do?

secures the proximal radioulnar joint

where is the origin and insertion of the lateral ulnar collateral ligament?

origin: lateral epicondyle

insertion: lateral olecranon

when is the interosseous membrane taut? what is its function?

5º of supination

prevents proximal displacement of the radius on the ulna

what is the function of the ulnar coronoid process? what provides varus/valgus stability at the elbow?

prevents posterior displacement

trochlea and ulnar fossa, in the last 30º of ext, the olecranon locks in the fossa providing valgus stability

T/F the joint capsule contains the humeroulnar and humeroradial joint and not the radioulnar joint

F, contains all 3 joints

what is the function of the anconeus?

is a dynamic stabilizer in response to varus stress and pronation/supination

initiates elbow ext but ineffective at full ext

what is the first muscle recruited with elbow flexion?

brachialis

which muscle is always active in elbow flexion?

brachialis

what muscle facilitates flexion in neutral forearm position?

brachioradialis

what muscle facilitates elbow flexion with forearm supinated?

biceps brachii

when is max elbow flex generated?

90º of flex

what position do triceps exert max torque?

90º of elbow flex

what are weak elbow flexors and pronators? (arise from medial epicondyle)

pronator teres, flexor carpi radialis, palmaris longus, flexor digitorum superficialis, flexor carpi ulnaris

what are weak elbow extensors and supinators? (arise from lateral epicondyle)

extensor carpi radialis longus and brevis, extensor digitorum, supinator, extensor digiti minimi, extensor carpi ulnaris

where is the olecranon bursa located?

posterior to the olecranon

T/F brachialis attaches to posterior capsule

F, attaches to anterior capsule

where does the ECRB originate?

lateral epicondyle but also annular ligament and radial collateral ligament

what are the peripheral nerves that cross the elbow?

ulnar, median, radial

what is the pathway of the ulnar nerve? what are common ulnar nerve injuries?

travels posterior to the medial epicondyle and through Arcade of Struthers (above elbow) and cubital tunnel

traction injuries with repeated elbow flexion, trauma, or cubitus valgus. vulnerable to compression in the cubital tunnel from hypertrophy of flexor carpi ulnaris and bony spurs

what is the pathway of the median nerve? what are common sites of compression?

courses through the two heads of the pronator teres

ligament of Struthers and pronator teres muscle can cause compression

what is the anterior interosseous nerve? what are common sites of compression?

motor nerve branch of the median nerve at pronator teres and travels deep in the forearm

can be compressed at pronator teres and deep forearm compartment leading to decreased FDP of index and middle, FPL and PQ

what is the pathway of the radial nerve? what branches from it? what are common radial nerve injuries?

travels from behind the humeral shaft around the lateral elbow into the supinator muscle and through the Arcade of Frohse

superficial branch of the radial nerve bifurcates here and contains only sensory nerve fibers

laceration or traction injury may occur with humeral shaft fractures. can also be compressed at the supinator muscle, Arcade of Frohse and ECRL

what is posterior interosseous nerve (PIN) syndrome?

the PIN is a branch of the radial nerve that provides motor innervation to the extensor compartment. it passes between the 2 heads of origin of the supinator muscle

PIN syndrome affects muscles it innervates. common extensors: ECRB, EDC, EDM, ECU, supinator, APL, EPB, EPL, EIP

has no cutaneous innervation

what are examples of functional outcome measures for UE?

Disability of Arm, Shoulder, Hand (DASH), quick DASH, Upper Extremity Functional Scale (UEFS), Patient Rated Wrist and Hand Evaluation (PRWHE)

what should your upper quarter scan consist of?

posture, ROM of cervical spine and shoulder complex, C-spine compression/distraction, neurological scan (reflexes, dermatomes, myotomes), special tests

what should you inspect about the skin around the elbow?

color, moisture (hyper/hypo hydrosis), wounds (location, size, color, drainage, odor), scars (flat, hypertrophic, hypersensitive, mobile, adherent, hyperemia)

what are other things you should inspect around the elbow?

deformities, muscle size (atrophy/hypertrophy), edema (measure circumference), bony prominences (medial and lateral humeral epicondyle, tip of olecranon), depression or infracondylar recesses (swelling if unable to see recess), carrying angle

what is normal carrying angle in men and women? how should you measure carrying angle?

men: 11-14º

women: 13-16º

should evaluate in full extension and full supination

what happens if you have exaggerated cubitus valgus and varus?

valgus: may cause traction neuropathy on ulnar nerve

varus: reversal of normal carrying angle (<5-10º)

what is normal elbow ROM? what is functional ROM?

ext/flex: 0-145º

pronation: 0-75º

supination: 0-80º

fxn ext/flex: 30-130º

fxn pron: 0-50º

fxn sup: 0-50º

T/F goni measurement for elbow and forearm ROM is highly reliable

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what are factors to consider when assessing PROM?

pain - when it occurs in arc of motion

quality of motion: smooth, crepitus, clicking

end feel - flex: soft, ext: hard, sup/pron: firm

what position of elbow is ideal to test accessory motion and perform joint mobilizations on elbow?

loose pack position

what is LPP, CPP, and capsular pattern of humeroulnar joint?

LPP: 70º flex, 10º sup

CPP: ext and sup

capsular pattern: flexion > extension

what is LPP, CPP and capsular pattern of proximal humeroradial joint?

LPP: full ext and full sup

CPP: 90º flex, 5º sup

capsular pattern: flex>ext, sup>pron

what is LPP, CPP and capsular pattern of radioulnar joint?

LPP: 70º flex, 35º sup

CPP: 5º sup

capsular pattern: sup and pron equally limited

what are the different accessory motion tests at the elbow?

humeroulnar joint: distraction, medial-lateral tilt

radiohumeral joint: anterior-posterior glide

proximal radioulnar joint: anterior/posterior glide

distal radioulnar joint: anterior/posterior glide

how to MMT elbow flex and ext? how to differentiate extensors?

elbow should be at 90º

test with forearm supinated (biceps b.), pronated (brachialis)

wrist flexion and extension

ECRL and ECRB: resistance applied to 2nd and 3rd MC

ECU: resistance applied to 5th MC

ED: pt resists with fingers extended

what are ligamentous tests at the elbow?

valgus and varus instability test, lateral pivot shift test of elbow

how to perform valgus instability test? what is a positive test?

humerus in full ext rotation, elbow flexed 20-30º

abduction or valgus force applied

+ test is pain, excessive gapping, motion at medial elbow

how to perform varus instability test? what is a positive test?

humerus in full internal rotation, elbow flexed 20-30º, apply varus stress

tests radial collateral ligament (isolated injury is rare)

what is the most common lateral ligament injury?

lateral ulnar collateral ligament, injury results in posterolateral rotatory instability

what does the lateral pivot shift test test for? what is a positive test?

indicates posterolateral rotatory instability due to lateral ulnar collateral ligament injury

pt lies supine with arm overhead, PT grasps pt wrist and forearm with elbow extended in full supination and applies valgus stress and axial compressive force while gradually flexing the elbow in supination

+ test: 40-60º there is a sudden reduction (clunk)

what is the Tinel sign?

indicates level of neuritis and nerve regeneration

+ if tingling and parasthesias along nerve distribution

what does the elbow flexion test used for? what is a positive test?

indicates Cubital Tunnel Syndrome

+ if produces paresthesias in ulnar nerve distribution, 15% of asymptomatic people are +

what is the pronator teres syndrome test? what is a postive test?

resist pronation and passively extend elbow to compress the median nerve even more (because it runs through the 2 heads of the pronator teres)

+ is reproduction of paresthesias in median nerve distribution

what is middle finger extension test? what is a positive test?

tests radial tunnel syndrome

+ if pain in radial tunnel

what is the tennis elbow test? what is a positive test?

tests for lateral epicondylitis

method 1: pt forearm at 90º pronated, resist wrist extension

method 2: PT passively pronates forearm, flexes wrist, extends elbow

+ is pain at lateral epicondyle and/or common extensor muscle insertion

what is the medial epicondylitis test? what is a positive test?

tests for Golfer’s elbow

PT passively supinates forearm and extends pt’s elbow and wrist

+ is pain over medial epicondyle

what is lateral epicondylitis (Tennis Elbow)? causes? sx?

def: a lesion affecting the origin of the muscles that extend the wrist (ECRL/ECRB, ED)

sx: overuse, repeated forceful pronation and supination, heavy lifting or hammering

s/sx: tenderness with palpation over ECRB at lateral epicondyle, pain with resisted wrist ext and radial deviation, pain with wrist radial deviation combined with active gripping, pain with passive wrist flexion and forearm pronation and full elbow extension; tenderness on outside of common extensor origin, pain over lateral elbow with gripping activities

what is medial epicondylitis? s/sx?

def: aka Golfer’s Elbow

s/sx: inflammation of the flexor mass of the medial condyle insertion, tenderness over medial humeral epicondyle, + medial epicondylitis test (pain with resisted wrist flexion when elbow is in full ext and supination); pain over medial elbow with wrist flex and forearm pronation

what is olecranon bursitis? causes?

inflammation of bursae between olecranon and the skin

usually caused by a single episode of trauma or repeated WBing, may or may not be painful

infection must be ruled out before dx

what causes bicep tendon rupture? s/sx?

rare, if so often from radial head dislocation. caused by unexpected extension force to elbow

s/sx: acute onset of swelling, pain, ecchymosis, decreased strength, increased discomfort

T/F biceps and tricep ruptures are rare

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what are nerves that are likely to be involved with an elbow problem?

cervical nerve roots (radiculopathy)

brachial plexus

ulnar n

median n → anterior interosseous n

radial n → posterior interosseous n and radial sensory n

what is cubital tunnel syndrome? causes? s/sx?

ulnar n entrapment

causes: entrapment in Arcade of Struthers, hypertrophied FCU, or trauma, cubitus valgus, bony spurs, tumors

s/sx: pain - vague dull aching in forearm, weak/atrophied FCU, FDP, interossei and lumbricals of 4th and 5th (Ulnar Claw deformity), hypothenar muscles and adductor pollicis (Froment’s) and deep head of flexor pollicis brevis, decreased sensation and paresthesia in ulnar nerve distribution; positive Tinel sign over cubital tunnel and elbow flexion test, Wartenberg’s sign (abduction of the small fingers)

what is pronator teres syndrome? s/sx?

compression of the median nerve as it dives through 2 heads of pronator teres in prox forearm (where AIN divides from MN and dives deeper into forearm)

s/sx: pain in anterior aspect of elbow and forearm, numbness and tingling in the MN distribution, motor weakness in MN distribution of wrist and hand, pain exacerbated by wrist flexion combined with elbow flexion and forearm pronation; positive pronator teres test, pain in volar 1/3 of forearm, paresthesias in median n. distribution, motor weakness in FCR, FDS, lumbricals of index and middle fingers, pronator teres

s/sx of anterior interosseous n syndrome?

no sensory symptoms, motor weakness in FPL, FDP to index and middle, can be identified by a positive “OK” sign, pronator quadratus weakness in forearm pronation tested with elbow in full extension

common with compartment syndrome

where is the radial nerve vulnerable to injury proximal to the elbow?

lateral upper arm - mid-humeral shaft fx, wrist drop/”Saturday night palsy”

axilla - compression over brachial plexus from crutches, wrist drop

what is radial tunnel syndrome? s/sx?

compression of the radial sensory nerve (5 cm distal to elbow in radial tunnel)

s/sx: constant pain but no motor weakness or paresis, pain increases with pronation and wrist flexion, tender distal to common extensor muscle mass insertion, positive middle finger extension test, pain with resisted supination with elbow extended (tunnel closed in supination)

what is posterior interosseous nerve syndrome? s/sx?

compression of posterior interosseous nerve as it passes through the 2 heads of supinator in the Arcade of Frohse

s/sx: same as radial tunnel but also with motor weakness, weakness in ED, EDM, EIP, EPB, EPL, APL, radial drift of wrist with active wrist extension due to weakness in ECU, possible weakness of supinator

radial tunnel syndrome vs posterior interosseous syndrome?

radial tunnel: involves pain without motor weakness

PIN: involves pain and motor weakness

what types of vascular lesions might affect the elbow?

brachial artery laceration - mx emergency

compartment syndrome - mx emergency

forearm compartment syndrome

rapid, excessive swelling which may impede or obliterate the blood flow

Volkmann’s contractures may result from prolonged intracompartmental pressure → nerve and muscle tissue death, needs immediate surgery

what fx are common around the elbow?

distal humerus - usually high impact injury

olecranon - fall on posterior elbow

radial head

monteggia - ulna fx with radial head dislocation at the elbow

galeozzi - radius fx with ulna dislocation at the wrist

elbow dislocation and joint pathology

radius/ulna - FOOSH - frequently associated with ulna fx, make sure to check for ulnar n dysfunction

radial head - common in adults, reduction is imperative

pulled elbow syndrome - radial head dislocation in children

what is stiff elbow? types?

Proximity of brachialis and triceps to the joint and the complexity of the 3 bone articulation give the elbow the propensity for stiffness

Myositis ossificans - ossification of the muscles, will see decrease in ROM and increase in pain

Heterotrophic ossification - formation of organized bone within and about the elbow joint

Common with open injuries, fracture dislocation- require aggressive PROM