FRACTURES OF THE PROXIMAL HUMERUS

Presented by

Mahsa Mehdizade

Dr. Mardani

Porsina Hospital

Spring 1392

Incidence

Proximal humerus fxs comprise 4-5% of all fxs.

Minimal displacement 80%

Two-part fxs 10%

Three-part fxs 3%

Four-part fxs 4%

Articular surface fxs 3%

Anatomy

Comprised of four segments:

Humeral head

Greater tuberosity

Lesser tuberosity

Humeral shaft

Neurovascular SupplyAnterior and posterior humeral circumflex arteriesArcuate artery-continuation of the ant humeral circumflex and supplies most of the humeral head.Axillary nerve-most commonly injured

Forces on Segments

Greater tuberosity is displaced superiorly and posteriorly by the supraspinatus and external rotators.

Lesser tuberosity is displaced medially by the subscapularis.

The shaft is displaced medially by the pectoralis major.

Mechanism of Injury

Elderly, osteoporotic, usually female: fall on outstretched arm.

Young adults: high-energy trauma; usually more severe fxs and dislocations

Radiographic Evaluation

A/P view

Scapular Y view

Axillary viewBest view for glenoid articular fxs and dislocations

CT scan: helpful in evaluating articular involvement and degree of displacement

ClassificationsNeer-four parts: greater and lesser tuberosities; shaft; humeral head.

A part is displaced only if >1cm of displacement or 45 degrees of angulation is present.At least 2 views must be obtained

AO-emphasizes the vascular supply to the articular segment

Three types:• Type A: Extraarticular unifocal fxs• Type B: Extraarticular bifocal fxs• Type C: Articular fxs

Not commonly used

Neer Classification

Treatment OptionsClosed reduction

ImmobilizationEarly ROM if stable

External stabilizationPercutaneous pinsExternal fixatorIlizarov frame

Open reduction and internal fixation

Screw fixationTension bandingButtress platingFix-Clip system

Intramedullary fixation

Rush rods

Ender’s nails

Nails with interlocking screws

Excisional arthroplasty

Hemiarthroplasty

Fractures to Consider for Closed Treatment

Minimally displaced 2 part fx’s (or positional reduction of significant displacement)

GT fractures should be <5mm).

Minimally displaced 3- and 4-part fractures

Fractures to Consider for ORIF

Displaced GT fx (> 5 mm)

LT fx with involvement of articular surface

Displaced or unstable surgical neck fx

Displaced anatomic neck fx in young pt.

Displaced, reconstructible 3- and 4-part fractures

Fractures to Consider Hemiarthroplasty

Young/Middle agenonreconstructable articular surface (severe head split) or extruded anatomic neck

Elderlymany 4 parts

some severe 3 parts

most 3,4 part fracture dislocations

most head splits

Potential ComplicationsNeurologic injury

Brachial plexus-Stableforth reported an incidence of 6.1%Axillary-common

Vascular injuryStableforth also reported a 4.9% incidence of arterial injury with displaced fxs; most commonly the axillary arteryAn intact radial pulse doe not exclude an arterial injury so keep it in mind.

Complications cont.Avascular necrosis

Hagg and Lungberg reported an incidence of 3 – 14% with 3- part fxs and 13 – 34% with 4-part fxs, using closed reduction.

Nonunion (uncommon)Malunion – often associated with AVNAdhesive capsulitisMyositis ossificansInfection