Elbow Pathologies

Fractures at the Elbow Complex Etiology

Supracondylar fractures: 5-8 y.o.

Lateral condyle fractures: 5-10y.o.

Medial epidcondyle fracture: 8-14 y.o. w/ throwing athletes

Radial head fractures: Intra-articular elbow fractures

Fractures at the Elbow Complex Pathophysiology

Supracondylar fractures: fracture at distal humerus

Lateral condyle fractures: avulsion of lateral condyle by common extensor mechanism or impaction of radial head into lateral condyle

Medial epicondyle fractures: Traction from MCL and flexor mass avulsing the medial epicondylar apophysis

Radial head fractures: elbow instability, mechanical block to motion, injury to distal radioulnar joint

Fractures at the Elbow Complex Common SSx

Supracondylar fractures: Gross swelling, bruised, painful elbow w/ significant deformity and refusal to move limb, pain and swelling may extend into forearm w/ limited mobility

Lateral condyle fractures: Painful elbow that child is reluctant to use, swelling TOP on lateral side, wrist flexion can worsen

Medial epicondyle fractures: Painful after fall w/ maximal TOP medial epicondylar region. Mild swelling/bruising medial side, Minmal deformity

Radial Head fractures: Pain and TOP lateral aspect elbow. Limited elbow or forearm motion, supination/pronation, Swelling and ecchymosis

Fractures at the Elbow Complex MOI

Supracondylar fractures: FOOSH

Lateral condyle fractures: FOOSH + varus force

Medial epicondyle fracture: FOOSH, valgus overload during overhead activity (throwing)

Radial head fractures: FOOSH

Fractures at the Elbow Complex Anatomy

Supracondylar fractures: distal humerus, surrounding muscles, median nerve, brachial artery

Lateral condyle fracture: lateral condyle humerus, common extensor mechanism, radial head

Medial epicondyle fractures: medial epicondyle apophysis, MCL, flexor mass, ulnar nerve

Radial head fractures: radial head, articular surface, MCL, interosseous membrane

Fractures at the Elbow Complex Screening

Supracondylar fracture: Neurovascular injury, pink or white pulseless hand, compartment syndrome

Medial epicondyle: elbow dislocations, incarcerated within the joint, ulnar nerve sensory and motor skills

Radial Head: posterior interosseous nerve (PIN), ulnar nerve

Fractures at the Elbow Complex Imaging

X-ray AP and lateral Sail sign (grey shadowing surrounding joint)

Condyle fractures: internal oblique view

Radial: AP and lateral forearm, radial head alignment

Supracondylar: anterior humeral line, Baumann’s angle

Posterior Elbow Dislocation Etiology

Elbow dislocation, non-dominant arm slight predominance

Posterior Elbow Dislocation Pathophysiology

Hyperextension and abduction with compressive force into radius and ulna

Posterior Elbow Dislocation Common SSx

Prominent olecranon and foreshortened forearm in 45 degrees flexion

Pain, cyanosis, pallor, pulselessness - vascular injury, compartment syndrome

Paresthesias

Diminished radial pulse

Posterior Elbow Dislocation MOI

FOOSH

High energy mechanisms: MVA, Sports

Hyperphysiological valgus movements in extended elbow

Posterior Elbow Dislocation Anatomy

Humerus, ulna, radius, brachial artery, Ulnar, radial, median nerves, ligaments

Posterior Elbow Dislocation Screening

Neurovascular compromise

Vascular injury or compartment syndrome

Presence of a pulse does not reliably exclude arterial injury

Posterior Elbow Dislocation Imaging

AP and lateral X-ray

Angiograph after reduction

Medial and Lateral elbow Instability Etiology

Posterolateral Rotatory instability (PLRI) - Most common, previous surgery or elbow deformity

Valgus Instability (medial) - repetitive stress in overhead athletes

Varus Posteromedial Rotatory Instability (VPMRI) - humeral detachment of LLC

Medial and Lateral elbow Instability Pathophysiology

PLRI: sequential lateral to medial soft tissue disruption, LUCL to medial ligaments

Valgus Instability: aMCL, pMCL damage

VPMRI: posteromedial elbow subluxation, humeral detachment of LLC

Medial and Lateral elbow Instability Common SSx

Looseness of elbow, catching, popping, slide out of place

PLRI: recurrent painful click or snapping moving from flexion to extension

Valgus Instability: pain inside of elbow when throwing

VPMRI: Painful throwing motion and reduced throwing velocity

Medial and Lateral elbow Instability Test Cluster

Medial: Valgus stress test (0 and 20-30 degrees), Moving Valgus Stress test

Lateral: Varus stress test (0 and 5-30 degrees), Lateral Pivot Shift, Chair Push-up, and Tabletop Relocation

Medial and Lateral elbow Instability MOI

FOOSH

VPMRI: Varus internal rotation model

Medial and Lateral elbow Instability Anatomy

LCL complex: RCL, AL, LUCL

MCL complex: aMCL, pMCL, transverse

Coronoid process, radial head, muscles

Medial and Lateral elbow Instability Screening

Fractures, neruovascular injuries

other pathologies: osteochondritis dissecans

Chronic Instability

Medial and Lateral elbow Instability Imaging

X-rays - fractures

MRI, US for tendon/ligaments

Medial and Lateral Epicondylar tendinopathy Etiology

ME: Repetitive strain involving frequent gripping under load, forearm pronation, and wrist flexion, often linked with intense valgus stress during throwing/golf swings

LE: eccentric overload at the origin of common extensor tendon, repetitive forearm movements and overload

Risk factors: Poor mechanics, smoking, diabetes, obesity, 2> hours of repetitive wrist flexion/pronation

Medial and Lateral Epicondylar tendinopathy Pathophysiology

Degeneration (tendinopathy), recurrent microtears, vascular and fibroblastic elements replace normal tendon tissue

Fibrosis or calcification can occur - decreasing collagen strength and thickening tendons

Medial and Lateral Epicondylar tendinopathy Common SSx

ME: Pain on medial aspect of elbow, worse with gripping, throwing, forearm flexion, and pronation. Pain subsides with rest, morning exacerbation is common, TOP 5-10 mm distal to medial epicondyle

LE: Pain over lateral epicondyle of humerus, TOP latearl epicondyle, few mm distal to tip. Pain w/ resisted wrist extension, gripping, Decreased grip strength

Typically in dominant arm, pain can be intermittent and activity dependent. ME often reports associated numbness in ulnar nerve distribution

Medial and Lateral Epicondylar tendinopathy Test Cluster

Lateral: Cozen’s, Mill’s, Maudsley’s, TOP lateral epicondyle

Medial: Reverse Cozen’s, Passive stretch, TOP medial epicondyle

Medial and Lateral Epicondylar tendinopathy MOI

ME: Overuse/repetitive stress involving forearm pronation and wrist flexion, intense valgus stress

LE: Eccentric overload at common extensor origin, repetitive forearm movements and overloading

Medial and Lateral Epicondylar tendinopathy Anatomy

ME: Medial epicondyle of humerus, Common flexor tendon (FCR, Pronator teres most common), MCL, Ulnar nerve

LE: Lateral epicondyle of humerus, Common extensor tendon (ECRB), LUCL

Medial and Lateral Epicondylar tendinopathy Screening

ME: Cubital tunnel syndrome/ulnar neuritis, UCL injury, Cervical radiculopathy, ganglionic cyst

LE: Radial tunnel syndrome, Posterior interosseous nerve entrapment (PIN), local arthritis, Radiocapitellar pathology

Social history: occupation/hobby

Medial and Lateral Epicondylar tendinopathy Imaging

MRI if diagnosis is ambiguous

X-ray AP/lateral is usual

Ulnar Nerve Pathology at Elbow Etiology

Compression at elbow (Cubital tunnel syndrome)

Lack of protective cover (exposed in ulnar groove)

Repetitive movements: elbow flexion and extension

Dynamic nerve irritation, fractures in the area, scar tissue compression, joint stiffness

Ulnar Nerve Pathology at Elbow Pathophysiology

Pressure between ulnar nerve and overlying structures increase during elbow flexion

Neurapraxia, nerve irritation

Ulnar Nerve Pathology at Elbow Common SSx

Symptoms start slow

Numbness and parasthesia radiating distally to ulnar aspect of hand, 5th digit, ulnar aspect of 4th

Pain along medial forearm, worsened by elbow flexion (at night)

Difficulty with typing, buttoning, opening bottles

Motor symptoms usually revealed later

Ulnar Nerve Pathology at Elbow MOI

Compression - due to anatomical vulnerability

Repetitive flexion/extension - increase in pressure

Dynamic subluxation/dislocation - nerve slipping

Trauma

Contracture

Ulnar Nerve Pathology at Elbow Anatomy

Ulnar nerve, Medial epicondyle

FCU, FDP, Cubital tunnel retinaculum

Ulnar Nerve Pathology at Elbow Screening

Carpal Tunnel syndrome, C7/8 radiculopathy, tumor

Thoracic outlet syndrome, traumatic peripheral nerve lesions

medial epicondylitis

Ulnar Nerve Pathology at Elbow Imaging

EMG and Nerve conduction velocity

US - screening and follow up

MRI - ulnar nerve CSA

Radial Nerve Pathology at Elbow Etiology

Compression at the elbow, trauma, compression, inflammation, repetitive activities, space occupying lesions

Radial Nerve Pathology at Elbow Pathophysiology

PIN entrapment: pressure on pin can increase and lead to entrapment

Can present with/without loss of motor function

Radial Nerve Pathology at Elbow Common SSx

High radial nerve entrapment (above cubital fossa) - sensory and motor deficits

Radial nerve injury distal - finger drop, partial wrist drop

PIN syndrome - pain in forearm, wrist, weakness in finger metacarpal and wrist extension

Radial tunnel syndrome: Persistent lateral aspect elbow pain, distal to lateral epicondyle, worse at night, sharp shooting pain along dorsal forearm

Radial Nerve Pathology at Elbow MOI

Direct trauma - humeral shaft fracture

Compression

Mechanical compression

Overuse

Radial Nerve Pathology at Elbow Anatomy

Radial nerve, Posterior interosseous nerve, Superficial branch of radial nerve

Compression Sites: arcade of Froshe, Radial tunnel (5-10 cm from radiocapitellar joint

Radial Groove

Radial Nerve Pathology at Elbow Screening

Lateral epicondylitis vs radiocapitellar disease

RTS and LE may coexist, PIN entrapment requries objective motor dysfunction

Night pain, TOP 5cm distal to lateral epicondyle, pain w/ resisted supination suggest PIN entrapment over LE

Radial Nerve Pathology at Elbow Imaging

Nerve conduction test

US/MRI

Median Nerve Pathology at Elbow Etiology

Compression

Supracondylar Process Syndrome: compressed under bony spur, or ligament of struthers

Lacertus Fibrosus (LF) compression: acute compression, complication of partial or complete distal biceps tendon rupture

Pronator Teres Syndrome: Entrapment between heads of PT, triggered by prolonged/repetitive forearm pronation with forced elbow and finger flexion

Median Nerve Pathology at Elbow Pathophysiology

Compression points: Ligament of Struthers, lacertus Fibrosus, pronator teres

Concomitant compression: brachial artery, nerve entrapment syndrome

Transient neurapraxia to significant motor deficits

Median Nerve Pathology at Elbow Common SSx

Local pain and distal paraesthesia w/ resisted elbow flexion

Local pain and loss of pronation power w/ resisted forearm pronation

Supracondylar Process syndrome: related to median nerve compression

Pronator tunnel syndrome: symptoms triggered by prolonged or repetitive forearm pronation w/ forced elbow and finger flexion

Anterior interosseous nerve (AIN) syndrome: impairment in ability to pinhc with thumb and index finger due to palsy

Median Nerve Pathology at Elbow MOI

Compression, trauma, overuse

Median Nerve Pathology at Elbow Anatomy

Median nerve, runs with brachial artery

Anterior interosseous nerve (AIN)

Ligament of Struthers

Supracondylar process

Lacertus fibrosus

Pronator teres, FDS

Median Nerve Pathology at Elbow Screening

Associated vascular injury, elbow stiffness, AIN as a DDx

Median Nerve Pathology at Elbow Imaging

Non specific

Radial Head Subluxation (Nursemaid’s elbow) Etiology

Common in young hcildren 1-4 y.o.

Axial traction on a pronated forearm and extended elbow

Radial Head Subluxation (Nursemaid’s elbow) Pathophysiology

Annular ligament encircles radial head, symptoms from displacement of annular ligament

Radial head is subluxed from annular ligament

Radial Head Subluxation (Nursemaid’s elbow) Common SSx

Pain and inability to supinate forearm

Arm held at side, elbow slightly flexed, forearm pronated, unwilling to use or supinate

Pain localized to elbow, no swelling or ecchymosis

Radial Head Subluxation (Nursemaid’s elbow) MOI

Traction on pronated forearm with elbow in extension

Radial Head Subluxation (Nursemaid’s elbow) Anatomy

Radial head, annular ligament, radiohumeral joint, Proximal radioulnar joint

Radial Head Subluxation (Nursemaid’s elbow) Screening

Rule out fracture or dislocation

Persistent immobility - referral

Older children > 5 y.o. RHS uncommon

Radial Head Subluxation (Nursemaid’s elbow) Imaging

X-ray

Distal Biceps Rupture Etiology

Eccentric contraction of biceps, either acute event or repetitive flexion/supination movements

Hyperextension of already extended arm (missing a punch in boxing)

Predominantly Isometric (88%)

Distal Biceps Rupture Pathophysiology

Rupture

Biceps tendinopathy or enthesopathy (diseased tendon insertion) precede rupture

Acute compression of median nerve, displacing lacertus fibrosus causing it

Distal Biceps Rupture Common SSx

Audible Snap or pop at injury, Subsequent pain and weakness in elbow flexion (and supination)

Bruising over medial aspect of elbow or abnormal contour of distal biceps

Complete tear - acute pain present, settles with time

Cramping/weakness - dominant symptoms in tendinopathy/partial tears

Distal Biceps Rupture Test Cluster

Hook Test

Biceps Squeeze Test

Palpation for Gap - palpable defect near distal biceps

Distal Biceps Rupture MOI

Eccentric loading of resisting, actively flexed forearm

Hyperflexion of extended arm

Rupture normally at 0-10 flexion (89%)

Forearm normally supinated (82%)

Distal Biceps Rupture Anatomy

Distal biceps tendon, bicipital-radial bursa, lacertus fibrosus, median nerve, brachial artery

Distal Biceps Rupture Screening

Median nerve compression

DDx: degenerative enthesopathy, bicipitoradial bursitis, brachialis muscle injury

Distal Biceps Rupture Imaging

non-specific

Elbow Stiffness Etiology

Trauma, Prolonged immobilization, postraumatic arthritis, Hetertopic ossification (HO) - formation of mature bone around joint creating mechanical block, Joint incongruity, adhesions, pain, scarring,

Elbow Stiffness Pathophysiology

Highly congruent bony anatomy, relatively confined joint space,

Osseous impingement, soft tissue contracture or combination

Intrinsic contractures: intra-articular injures - adhesions, loss of cartilage, infection

Extrinsic contractures: Skin contractions, HO, neural adhesion, infection

Elbow Stiffness Common SSx

Movement impairment - affects ADLs

Limited ROM: pre-operative arc was 84degrees compared to 130-140 in normal

End range tenderness

Median nerve compression

Ulnar nerve entrapment signs: provoked during deep flexion, sleep disturbances

Elbow Stiffness MOI

bleeding, edema, granulation, fibrosis after trauma

Excessive capsular scarring

Hetertopic ossifcation (HO)

Prolonged joint immobilization

Elbow Stiffness Anatomy

Joint capsule, bony anatomy, ligaments, muscles, nerves

Elbow Stiffness Screening

Ulnar nerve exam, Pre-operative neruovascular assessment

Prognosis: ROM recovery after 3 weeks takes 3 months, max arc by 4 months post-op

Elbow Stiffness Imaging

X-ray - joint congruence

CT - suspected of osseous impingement or deformities