Fracture of humerus

Humerus Fracture

A humerus fracture is an injury to the bone of the upper arm. The upper arm bone, the humerus, connects the shoulder to the elbow. Humerus fractures are generally divided into three types of injuries:

  • Proximal Humerus Fractures : Proximal humerus fractures occur near the shoulder joint. The shoulder joint is a ball-and-socket joint, with the ball being the top of the humerus bone. Fractures of this ball are considered proximal humerus fractures. These fractures may involve the insertion of the important rotator cuff tendons. Because these tendons are important to shoulder motion, treatment may depend on the position of these tendon insertions.
  • Mid-Shaft Humerus Fractures : Mid-shaft humerus fractures occur away from the shoulder and elbow joints. Most humeral shaft fractures will heal without surgery, but there are some situations that require surgical intervention. These injuries are commonly associated with injury to one of the large nerves in the arm, called the radial nerve. Injury to this nerve may cause symptoms in the wrist and hand.
  • Distal Humerus Fractures : Distal humerus fractures are uncommon injuries in adults. These fractures occur near the elbow joint. These fractures most often require surgical treatment unless the bones are held in proper position. This type of fracture is much more common in children, but the treatment is very different in this age group

Proximal humerus fractures

Epidemiology

  • 4-5% of all fractures

Mechanism of injury

  • Usually after fall onto an outstretched hand from standing height
  • Can also occur during seizures or electric shock when fracture may be associated with a posterior shoulder dislocation
  • Can also result from a direct blow

Age group affected

  • Middle age/elderly most commonly affected. Common in women. Many patients are osteoporotic.
  • n younger people, same injury mechanism can cause fracture with co-existing shoulder dislocation. In younger age groups, trauma is likely to be of higher energy and resulting injury more serious. Humeral epiphysis separation can occur in adolescents.

Presentation

  • History of trauma
  • Pain, loss of shoulder/arm function, swelling and bruising .

Investigations

  • Xrays – include AP, transscapular (or Y) and axillary views
  • CT scan may be needed in difficult cases

Classification

  • Neer classification: based on the 4 usual cleavage lines that occur due to the anatomy of the proximal head of the humerus (the articular segment or head, the lesser tuberosity, the greater tuberosity and the surgical neck/shaft). Two-part, three-part and four-part fractures can occur. The fractures are then classified by their degree of displacement and angulation.
  • Considered to be displaced if more than 10mm movement or angulation >45º.
  • Surgical neck fractures are the commonest type of proximal humeral fracture.

Management

  • General principles: the fracture should be immobilized as soon as possible and potent analgesia given. Keep patient comfortable and minimise any need for movement. Open fractures, those associated with a shoulder dislocation or combined with fracture in forearm are a surgical emergency and an immediate orthopaedic opinion is necessary.
  • Most fractures are extra-articular and minimally displaced.
  • Up to 85% of proximal humerus fractures can be treated non-operatively. This involves the use of a sling or shoulder immobiliser. A physiotherapy referral should be made.
  • If displaced, surgery may be needed but which surgical technique is used is controversial. Some advocate the use of conservative treatment for some displaced fractures.
  • Surgery involves either closed reduction with percutaneous fixation, open reduction and internal fixation, or proximal humeral head replacement.
  • Fracture dislocations and fractures of the anatomical neck should be referred for orthopaedic review.

Complications

  • Neurovascular injury: 21-36% of proximal humerus fractures produce neurovascular injury. Axillary nerve damage is most common. Suprascapular, radial and musculocutaneous nerves can also be affected. Axillary artery injury may rarely occur (look for expanding mass over proximal shoulder girdle). Brachial artery is also rarely injured.
  • Avascular necrosis of the humeral head: more common in complex fractures with multiple fragments where interruption to the blood supply is more likely and in fractures of the surgical neck. Causes pain and stiffness in the shoulder. Shoulder arthroplasty may eventually be needed or may be the initial treatment of choice in the fracture management. However, the development of intramedullary nails and minimally invasive locking plates provides greater ability to fix more complex fractures with less risk to the blood supply.
  • Malunion
  • Associated glenohumeral dislocation
  • Associated rotator cuff injury

Prognosis

  • This depends on fracture type, mechanism of injury and patient’s age and underlying health. In general an elderly person with a proximal humerus fracture never regains full range of movement, whether treated conservatively or surgically. The aim is rehabilitation to a functional range of movement.
  • Generally recovery takes at least 1 year but union is expected at 6-8 weeks.

Prevention

  • Adequate treatment of those at risk of osteoporosis

Hill-Sachs lesion

This is a type of proximal humerus fracture. It is defined as a posterolateral humeral head compression fracture and can occur following anterior shoulder dislocation. It occurs in 35-40% of anterior dislocations and up to 80% of recurrent dislocations. Xray views should include an AP view of the shoulder in internal rotation and a special view known as the Stryker Notch view.The reverse Hill-Sachs lesion is a compression fracture of the anteromedial humeral head as a result of posterior shoulder dislocation.

Humeral shaft fractures

Epidemiology

  • 3% of all fractures
  • 3% of fractures in children <16

Mechanism of injury

  • A swedish study in 2006 found most are caused by a simple fall
  • May be linked to non-accidental injury in children <3 years
  • Usually direct trauma or torsion injury to upper limb. Occasionally fall onto outstretched abducted arm. Blunt injury/bending forces usually cause transverse fractures. Torsional force tends to result in spiral fracture.

Age group affected

  • The swedish study found that most fractures occurred in elderly patients.

Presentation

  • History of trauma
  • Arm pain, swelling and deformity

Investigations

  • AP and lateral Xrays of the humerus
  • Include views of the shoulder and the elbow

Classification

There is no recognised universally accepted classification. Can be described using:

  • Location – proximal, middle, distal. Distal third humeral fractures are also known as Holstein-Lewis fractures.
  • Type of fracture line – transverse, oblique, spiral, comminuted, segmental
  • Open or closed

Management

  • The same general principles as listed above should be applied.
  • Most can be treated non-operatively in a hanging arm cast or coaptation splint (a splint from the axilla to the nape of the neck with a stirrup around the elbow) followed by a functional arm brace (this has an anterior and posterior plastic shell held together by adjustable Velcro straps) after 1-3 weeks. A physiotherapy referral should be made.
  • Mildly displaced/overlapping humeral shaft fractures may be treated by closed reduction and long arm splint from shoulder to wrist. After any humeral closed reduction, neurovascular assessment and x-rays should be repeated.
  • Surgical fixation may be needed if the fracture is segmental or if there is vascular compromise. This involves open reduction and the use of plates and screws or intramedullary fixation/nailing. Radial nerve injury, which may only be temporary, is a risk in any operative procedure.

Complications

  • Radial nerve injury: occurs in 11.8% of fractures. Most common in distal third fractures. More common in transverse or spiral fracture. Spontaneous recovery occurs in 70.7% treated conservatively. Initial expectant treatment may avoid unnecessary operations.
  • Brachial artery injury
  • Non-union

Prognosis

  • Usually heal within 4 months

Fractures of distal humerus

  • Supracondylar/transcondylar – most are extension-type injuries from fall on outstretched arm.
  • Transcondylar fractures are more common in elderly.
  • Supracondylar fractures are more common in children.
  • Patient usually presents with elbow swelling and pain.
  • Careful examination for neural or vascular involvement due to risk of damage to brachial artery and nerve.
  • Marked swelling of forearm or palpable induration of forearm flexors, with pain on passive extension of the fingers suggests acute volar compartment syndrome requiring emergency fasciotomy.
  • AP and lateral X-rays of elbow.
  • Images of transcondylar fracture and its repair.

Management

  • All but non-displaced or minimally displaced fractures without neural or vascular involvement should be referred for surgical repair.
  • Immobilize elbow in long arm posterior splint with elbow at 90° degrees forearm in neutral rotation.
  • Check distal pulses after splint applied and if absent, extend elbow to point where pulses return.
  • Frequent checking of neural and vascular function essential during first 7–10 days, ice and elevation are important in reducing swelling.
  • Re-examine within 24–48 hours.
  • After 2 weeks, patients should remove splint and perform gentle exercises and continue using splint for approx. 6 weeks, then start vigorous exercises.

Intercondylar fractures

  • T- or Y-shaped fractures with varying displacement between the condyles and the humerus.
  • Commonly caused by direct or indirect blow to elbow.
  • Patient usually presents with marked tissue swelling holding their forearm in pronation.
  • Injured forearm may appear shortened.
  • May feel crepitus of movement when condyles are pressed together.
  • AP and lateral views of intercondylar fracture.

Management

  • Most fractures require surgery because they are displaced.
  • Refer for orthopaedic opinion.
  • Rarely, non-displaced fractures can be treated similarly to non-displaced supracondylar fractures, as above.

Condylar fractures

  • Lateral condyle fractures are more common than medial.
  • Lateral fractures are usually due to direct impact on a flexed elbow.
  • Medial due to impact to olecranon with flexed elbow.
  • Sudden adduction or hyperextension may also cause these fractures.
  • Patients usually present with swelling, limited range of movement and tenderness over injured condyle.
  • Crepitus with motion is frequently present.
  • AP and lateral x-rays reveal a widened intercondylar distance and there may be displaced fracture fragments.

Management

  • Aspiration of joint haemarthrosis relieves discomfort.
  • Displaced fractures require surgical correction.
  • Undisplaced fractures can be treated with a long arm posterior splint with elbow at 90°.

Radial head and neck fractures

  • Radial head fracture is the commonest fracture around the elbow joint in adults, whereas radial neck fractures occur more commonly in children.
  • Most commonly due to fall on outstretched arm.
  • Patient presents with swelling over the lateral elbow with limited range of motion, particularly forearm rotation and elbow extension ± elbow effusion and bruising. Pain increased with passive rotation.
  • Most reliable clinical sign is point tenderness over radial head.
  • Needs careful assessment for nerve and vascular involvement, especially with brachial artery, median and ulnar nerves.
  • Important to detect a mechanical blockage of motion from displaced fracture fragments. Often needs aspiration of the haemarthrosis with instillation of local anaesthetic for pain relief.
  • Presence of severe crepitation or complete blockage of motion for full extension and flexion shows presence of displaced fragments.
  • If there is significant wrist pain and/or central forearm pain, may be acute longitudinal radioulnar dissociation with disruption of the distal radioulnar joint.

Investigations

  • AP and lateral X-ray views of elbow are usually sufficient.
  • Findings may be quite subtle and only clue may be fat pad sign (triangular radiolucent shadows anterior and posterior to distal humerus on lateral x-ray, indicating haemarthrosis and displacement of intra-articular fat pad – often associated with intra-articular skeletal injury).
  • Image of elbow fat pad sign. Images of radial head fractures.

Management

  • Refer for urgent surgical treatment if elbow fracture-dislocation or evidence of nerve or vascular involvement.
  • Complex fractures require open reduction and internal fixation.
  • Otherwise give sufficient analgesia and consider joint aspiration and instillation of anesthetic as described above (usually in expert hands).
  • Immobilize elbow in long arm posterior splint with elbow at 90°.
  • In non-displaced fractures, remove posterior splint and replace with sling for comfort only, monitor for displacement and institute active range of movement exercises, including rotation, flexion and extension at least 3–4 times daily.

In children

  • Can be difficult to diagnose as radial head ossification does not occur until age 4.
  • May be associated ulna shaft fracture (equivalent to adult Monteggia fracture).
  • US or MRI may be needed to confirm the diagnosis.

 

Olecranon fractures

  • Low energy fractures occur most commonly in the elderly and result from indirect trauma due to sudden pull of triceps and brachioradialis muscles.
  • In younger patients usually follow direct blow to the point of the elbow and are often comminuted and may have associated ulna shaft fracture.
  • Patient presents with swelling and tenderness over the olecranon with haemarthrosis and limited range of motion.
  • An inability to extend the elbow against gravity indicates dysfunction of triceps lever.
  • Need to check for ulnar nerve damage and examine distal pulses.
  • True lateral X-ray of elbow should reveal the fracture.

Management

  • Immobilise elbow in long arm posterior splint with elbow in 60–90° flexion, well moulded posteriorly.
  • Support arm with collar and cuffs or standard arm sling.
  • Refer displaced fractures for surgery. In non-displaced fractures, splint for 5–7 days, remove and repeat x-ray to confirm non-displacement.
  • If still stable, gentle supination and pronation exercises using a sling or removable posterior splint for comfort.
  • Flexion and extension exercises after 2 weeks.

Fractures of the coronoid process

  • Associated with elbow dislocation in about 40%
  • Patients present with tenderness over antecubital fossa and swelling about the elbow.
  • Check strength of radial pulse with elbow at 90°.
  • Lateral X-ray of elbow.
  • Image of coronoid fracture.

Management

  • Non-displaced fractures should be immobilised in long arm posterior splint with elbow at 90° and forearm in full supination. After 3 weeks, start active range of movement exercises using sling for comfort.
  • Displaced fractures or those involving >50% of process need surgical repair.

Capitulum Fracture

  • Fracture involving the distal humeral articular surface.
  • Usually fall onto outstretched hand or direct trauma.
  • Present with anterior elbow pain and effusion.
  • Lateral and AP radiography usually reveals the fracture.
  • Images of capitulum fracture.
  • Management: undisplaced fractures may be splinted but more usually they are displaced and require surgical fixation.

Elbow dislocation

  • Very common especially in young people undertaking sport.
  • Often due to fall onto extended elbow.
  • Those without fracture are termed simple whereas dislocations with fracture are termed complex.
  • Classified according to position of ulna in relation to humerus after injury.
  • Often associated with injury to brachial artery and nerve so full examination of distal pulses, median and ulnar nerve function.
  • Patient usually presents with severe pain with elbow flexed and swelling and deformity apparent.
  • AP and lateral X-rays of elbow to confirm dislocation and exclude fractures.
  • Image of lateral view of posterior dislocation.

Management

  • Prompt reduction essential. This is usually performed under IV sedation and with adequate analgesia.
  • Posterior dislocation
  • First try countertraction on the humerus while applying longitudinal traction on the wrist and forearm.
  • Continue distal traction as elbow is flexed.
  • May need downward pressure on proximal forearm.
  • If this fails, place patient face down with elbow hanging off side of table and place small pillow under the humerus just proximal to the elbow joint and hang a 2½–10 kg weight from the wrist or apply gentle longitudinal traction.
  • Usually reduces within several minutes but may need forward pressure on the olecranon.
  • Anterior dislocation
  • Basically the reverse of above applying posterior and downward pressure to the forearm whilst applying anterior pressure from behind to the distal humerus.
  • After reduction, test joint mobility and stability and check neural and vascular function. Repeat x-ray and immobilize elbow in posterior splint with elbow at 90°.