Humerus Fractures

Fractures of the Proximal Humerus

Classification: (Neer )

ref: Neer, C. S. " Displaced proximal humeral fractures. Part 1. Classification and Evaluation"
JBJS 52A: 1077-1089, 1970
Four segment terminology applies only to displaced fractures
Displaced fractures:
Separation of fragments by at least 1cm or angulation of at least 45o.
All other fractures referred to as minimal displacement regardless of the number of fragments
Displaced fractures account for 20% of all proximal humeral fractures

One Part

If the criteria for displacement are not met then the fracture is considered minimally displaced and there is only one part

Two part

(10%) one major segment displaced
may be:
2 part anatomical neck fracture
2 part surgical neck fracture
2 part greater tuberosity fracture
2 part lesser tuberosity fracture

Three part

Unimpacted surgical neck fracture and displacement of either the greater or lesser tuberosity
Circulation to the humeral is head usually adequate to treat by internal fixation and cuff repair through a delto-pectoral incision

Four part

Displacement of both tuberosities deprives the head of adequate circulation and the detached head usually undergoes avascular necrosis
Usually ® hemi-arthroplasty unless particularly young
Fracture dislocation
2 part:
anatomical neck
surgical neck
greater tuberosity
lesser tuberosity
3 part:
4 part:
Impression and Head Splitting fractures

Treatment

Two part fracture

anatomical neck
-rare
young pt - ORIF
old pt - primary hemiarthroplasty
surgical neck
the shaft is displaced medially by Pec major
unimpacted, displaced fracture
  1. aim for CR and percutaneous pinning
  2. if CR not possible - then ORIF with either suture or wire
    impacted, angulated more than 45 deg
  1. disimpact by closed means, correct angulation
  2. percut pin if necessary
comminuted
  1. CR
  2. ORIF if CR unsuccessful / unable to maintain reduction
greater tuberosity
ORIF using nonabsorbable suture and repair of the rotator cuff
lesser tuberosity
rare
if fragment small - nonop with early ROM exs
if fragment large +/- blocks med rotation - ORIF

Three part fractures

are unstable - CR unsuccessful
® ORIF in active pts
Nonop only in low demand pt or when surgery contraindicated

Four part fractures

in the young pt attempt ORIF
otherwise ® prosthetic replacement (hemi-arthroplasty)
Requirements for stability are to cement the humeral component if any movement to enable early mobilisation of the arm
Length of the shaft, height and version of the prosthesis
Rotator cuff integrity

Fracture dislocations

2 part
anatomical neck - v rare - primary hemiarthroplasty in all but the young pt
surgical neck - v rare - CR +/- ORIF
greater and lesser tuberosity - Closed reduction - the head is attached to the shaft and it is hoped that the displaced tuberosity fragment will be reduced to an acceptable position.
NB: tendency for redisplacement of the tuberosity fragment - esp gt tuberosity. If tuberosity displaced - ORIF
3 part
ORIF
4 part primary hemiarthroplasty

Impression fractures

if less than 20% of head involved - usually no action required
if 20-45% of head involved - McLaughlin procedure
if > 45% of head involved - hemiarthroplasty

Head Splitting fractures

require a hemiarthroplasty unless pt young
(ORIF assoc with frequent failure)

Complications

Vascular
injury to the axillary artery - accounts for ~ 6% of all arterial trauma
Brachial plexus
injured in 6% of cases
Myositis Ossificans
rare but more common after fracture dislocations
Joint stiffness
due to both the fracture and sny surgery - need to structure rehab
AVN
2 part fracture rare
3 part fracture 3- 14 %
4 part fracture 13 -34%
Nonunion
rare - due to displacement, comminution, soft tissue interposition etc
Malunion
surgical neck - osteotomy if limiting ROM, producing instability
greater tuberosity - ORIF
lesser tuberosity - ORIF if causing mechanical block or instability
3 part fracture - options are osteotomy and internal fixation , or , hemiarthroplasty
4 part fracture - hemiarthroplasty

Fractures of the Humeral Shaft

Classification

by location, fracture pattern, comminution, soft tissue injury, mechanism

AO

Type A simple

A single circumferential disruption of the diaphysis - may be :
  1. Spiral
  2. Oblique ( angle >30 deg)
  3. Transverse (angle less than 30 deg)

Type B multifragmentary: wedge

A fracture with one or more intermediate fragments in which after reduction, there is some contact bw the main fragments- may be:
  1. Spiral wedge
  2. Bending wedge
  3. Fragmented wedge

Type C Multifragmentary: complex

A fracture with one or more intermediate fragments in which after reduction , there is no contact bw the main prox and distal fragments- may be:
  1. Spiral
  2. Segmental
  3. Irregular

Anatomy

Fracture above the level of pectoralis major allows the prox fragment to abduct and rotate internally due to the action of the rotator cuff

Fracture above the deltoid + below pec major - deltoid pulls the distal fragment laterally, pec major pulls the prox fragment medially

Fracture below deltoid - prox fragment abducts due to deltoid, distal fragment pulled medially and proximally by biceps/ brachialis and coracobrachialis

NB: Holstein- Lewis fracture where the radial nerve is caught bw the bone ends - when the fracture is reduced eg by the effect of gravity using a U- splint, radial nerve is compressed in the fracture and thus get a radial nerve palsy

Treatment

Nonoperative Options

  1. Hanging cast
  2. U- shaped coaptation POP
  3. Shoulder spica
  4. Skeletal traction
  5. Functional bracing

Operative options

Recommend closed management unless definite indication for open treatment as high rate of success using closed means

Indications for ORIF

  1. compound fracture
  2. multiple trauma
  3. failure to obtain or maintain reduction with closed means
  4. neurovascular injury
  5. pathological fracture
  6. fracture in assoc with displaced intraarticular fracture

Complications

Fracture

radial nerve injury - 5-10% - most at risk in distal 1/3 shaft fracture
- most are neuropraxia and function will return in days to mths. Where the nerve lesion is a complete division, delayed repair achieves as good results as acute repair. Thus there is little need to explore the radial nerve acutely unless there is another indication for ORIF of the fracture.
- monitor the pt - if no sign of recovery within 3-4/12 on either clinical or EMG grounds = indication for exploration
Vascular injury - to brachial artery

Nonunion

higher risk in transverse fracture, compound fracture , high energy trauma
= no sign of union by 4 mths
treat with ORIF and BG - expect 95% to unite

ORIF

infection rare ~ 1%
nonunion rare ~ 3%
radial nerve injury

R/O metal high risk to the radial nerve ~ 16%

Fractures of the Distal Humerus

ref: Jupiter " complex fractures of the distal part of the humerus and associated complications"
JBJS 76A: 1252- 1264, 1994

Classification AO


Type
  1. Extra articular
  2. partial intraarticular
  3. complete intraarticular

Med and Lat Condylar fractures ( Milch )

Type
  1. the lat condylar ridge remains intact providing stability med to lat
  2. lat condylar ridge is part of the fractureed condyle
- if there is assoc capsular/ ligamentous disruption (medially for fracture lat condyle and laterally for fracture med condyle), this allows the radius and ulna to translocate med to lat or lat to med respectively

Capitellar fractures


Type
  1. ( Hahn- Steinthal) involves a large part of the osseous portion of the capitellum and may contain part of the adjacent lip of the trochlea
  2. ( Kocher- Lorenz) involves artic cartilage with little bone attached

Treatment


Closed

  1. cast immobilisation
  2. traction
  3. early motion ( bag of bones)

Operative

  1. pins in POP
  2. ORIF - limited or formal
  3. distal humeral replacement - prosthetic or allograft
  4. arthroplasty
Recommend:
closed treatment for undisplaced/ min displaced fracture
ORIF for displaced fracture in all but the v low demand pt

Paediatric Fractures of the Distal Humerus

If unsure about the anatomy or possible injury in children X-Ray the normal side and look at location and development of epiphyses
Order of ossification "CRITOE" capitellum, radial head, inner or medial epicondyle, trochlea, olecranon and finally external or lateral epicondyle

Supra-condylar Fractures of Humerus

Classification

97% are extension injuries
Type
  1. Non-displaced
  2. Displaced but posterior cortex intact - ie post angulation of distal frag
  3. Displaced and no cortical contact
By far the greatest majority are extended and stable once reduced and held in flexion

Complications:
Neurological in 7% of fractures (20% from Adelaide series)
Vascular in 0.5% (distinguish ischaemic limb from perfused hand with no pulses)
Compartment syndrome in 0.1%
Cubitus varus develops in 5 - 40%

Lateral Condyle Fractures

Comprise 17% of distal humeral fractures and generally require ORIF to ensure joint surface reduced
Most common Salter Harris IV Type fracture involving avulsion of Henry's mobile wad (Brachioradialis, ECRL and ECRB)
Classification: Milch
  1. fracture enters jt lat to crista of trochlea (= SH 4)
    thus can get growth arrest
    elbow is stable
  2. fracture enters medial to crista of trochlea (= SH 2)
    growth arrest unlikely
    elbow is unstable
Anatomic reduction is mandatory generally ® ORIF and K wire fixation followed by AEPOP for 6/52
Care not to strip soft tissue from the distal fragment - the blood supply of the lat condyle is mainly from posterior - thus stay anterior

Medial Epicondyle

Generally can be managed conservatively in a flexed and pronated position unless widely separated from the distal humerus
may need ORIF esp if fragment displaced into the jt

Dislocation

Reduction may require anaesthetic and at the time ® EUA to assess instability
Children ® X-Ray following reduction to check location of the medial epicondyle
There is no evidence that the results of surgical repair of collateral ligaments is superior to those of non surgical treatment
Once reduced and found to be stable the limb could be immobilised in a sling for 2 - 3 weeks
If the elbow was found to be unstable (particularly in extension) they should remain in the sling for 3 - 4 weeks