Proximal humerus fracture

General

The proximal humerus is essentially the ball part of the shoulder joint.

 The shoulder in simple terms is a ball and socket joint.

 The proximal humerus is made up of four different pieces.

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The joint surface (articular surface)

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The greater tuberosity

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The lesser tuberosity

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The shaft.

Fractures of the proximal humerus may be simple or complex depending on how these different pieces have been broken apart and how many

pieces it has been broken into.

The simplest fracture configuration being an undisplaced fracture.

There may be one or several fracture lines in the head and across the neck but the pieces have not moved far apart.

A two part fracture is where the proximal humerus has been broken into two pieces and they have moved apart (displaced).

A three part fracture is a fracture where the proximal humerus has broken into three pieces and a four part where it has broken into four pieces.

Generally the greater the number of pieces the more complex the injury and the more likely surgery will be offered.

 If the joint surface is disconnected from its blood supply there may be potential for avascular necrosis (this is where the head dies)

Diagnosis

X rays are needed to be able to tell if the proximal humerus has been broken.

If the injury is simple, often all that is needed are good quality x rays.

If it is a complex injury (3 or 4 part), or if the x rays are not good enough to show the exact nature of the injury then a CT scan may be needed.

Treatment

Treatment may be operative or non operative.

Several variables are considered when deciding the optimal treatment.

The variables considered include.

Injury severity (undisplaced, 2 part, 3 part or 4 part fracture)

Fracture pattern, exactly which parts are broken.

Patient functional demands and expectation.

It is very much a case of balancing the risks of any treatment with the potential benefits.

As such in some cases a 4 part fracture will be treated non operatively in one patient, operatively and fixed with plate and screws and in another case

treated with a joint replacement.

Non operative treatment

Non operative treatment is generally reserved for undisplaced or minimally displaced two part fractures.

It may be chosen in patients not fit for surgery or where surgery is unlikely to lead to improved function.

The absolute treatment and rehabilitation regimen depends on what pieces have been broken.

Operative treatment 

Operative treatment is usually reserved for complex displaced fractures.

The operative treatment options include:

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Open reduction and internal fixation with plate and screws

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 Open reduction and internal fixation with intramedullary nail

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 Open or closed reduction and fixation with threaded k wires.

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 Shoulder joint replacement (hemiarthroplasty).

Outcome

The outcome is extremely variable depending on the severity of the injury, the treatment chosen and the rehabilitation after the injury.

In general if a proximal humeral fracture is treated and fixed with a plate and screws you will achieve elevation of 130°.

If the joint needs to be replaced (hemiarthroplasty), on average patients achieve elevation of 90°, but you avoid the potential problems of avascular

necrosis.