Humeral shaft fracture
X-ray of a normal humerus showing the long shaft


Fracture of the humerus shaft comprises a break of the long humeral bone between its extremities: the humeral head, joining at the shoulder joint with the glenoid fossa of the scapula, and the distal humeral head forming the elbow joint. The humeral shaft is the middle portion of the bone.

Left: X-ray of a complex humerus shaft fracture; Right: Image of radial nerve damage caused by a humeral fracture


The fractures of the humerus shaft represent 3-5% of all fractures. They can occur at any level of the humerus shaft including the proximal, middle or distal humerus. The involvement of the radial nerve is critical in humerus shaft fractures. This nerve travels along the humerus from the humerus neck to the hand, and spirals closely around the bone shaft. Fractures of the humeral shaft can damage the radial nerve causing the inability to extend (bend) the wrist and the fingers backwards (drop hand). Injury to this nerve is caused by its entrapment within the bone break.

Fractures of the humerus shaft showing a transverse, oblique and spiral type.


Fractures of the humerus shaft can display various patterns: transverse, oblique, spiral, and comminuted. In addition they are differentiated depending on whether the fracture is displaced or undisplaced, relative to the loss of bone alignment and closed or open fracture. The AO (Arbeitsgemeinschaft für Osteosynthesefragen) Foundation, an international organisation founded in Switzerland, focussing on research and education for the management of orthopaedic injuries), is one of most used systems available to characterise humerus shaft fractures. According to the AO humerus shaft fractures are divided into their level of comminution:

Type A - No comminution

Type B - Presence of butterfly fragment (wedge-shaped fragment of bone

Type C - Comminution

Fractures of the humerus shaft showing a transverse, oblique and spiral type.
Fractures of the humerus shaft showing a transverse, oblique and spiral type.
Road traffic accidents are a frequent cause of humerus shaft fractures


Fractures to the humeral shaft are mostly caused by trauma with only a small percentage due to underlying conditions that weaken the bone density (osteoporosis, cancer, Paget's disease). This type of fractures is common among middle-aged and elderly people, mostly women, due to low energy falls. More commonly in younger males, humerus fractures often result from high-energy impact injuries with direct trauma to the arm and torsion of the upper extremity. They often coexist with a shoulder dislocation. In this young population humerus shaft fractures are caused by road traffic accidents and sport injuries.

Contact sports with high energy impact increase the risk of a humerus shaft fracture

Risk factors

The most frequent risk factors leading to a humeral shaft fracture include:

Tendency to fall in elderly individuals (poor vision, lack of physical exercise)

Medical conditions (diabetes, seizure)

Sports (bicycle, horse riding)

Contact sports (football, rugby)

Post-menopausal age in women  

Cancerous metastases

Pain on the upper arm is the main symptom following a humeral shaft fracture


The symptoms arising from a humerus shaft fracture are quite evident:

Sudden sharp pain on the upper arm at time of injury

Snapping noise

Deformity of the upper arm

Shortening of the upper arm

Crepitus with arm movement and palpation Significant swelling

Subcutaneous bleeding

Inability to raise the arm

Increasing pain when attempting to move the arm

Radial nerve palsy

A bruised arm following a humerus shaft fracture


Clinical examination begins by discussing the medical history including the causes leading to a humeral shaft fracture. The main scope of the diagnosis is to determine the type of humerus shaft fracture to develop an optimal treatment plan suitable to the specific fracture. It is critical for the examiner to assess potential damage caused to the radial nerve and the vasculature. Clinical examination will determine:

Changes in the anatomy of the upper arm and bone deformities

Presence of bruises and lacerations in case of open fractures

Functional restriction in the range of movement of the arm

Increasing pain while moving the arm

Neurological symptoms relative to the radial nerve

Peripheral pulses to evaluate possible vascular injury

X-rays are taken under different angles to ascertain the type of humerus shaft fracture and whether the elbow and shoulder joints have been affected by the injury. A CT scan and MRI may be requested in more complex cases. Severe multiple injuries to the humerus shaft can lead to secondary complications and require immediate attention at the Emergency Department including the examination by an orthopaedic surgeon.


Patient with a humerus shaft fracture treated conservatively with a cast

Nonoperative treatment

In case of undisplaced or minimally displaced humeral fractures, conservative treatment is standard management. Nonoperative treatment is also accepted in case of relatively small displacement with a 30-40° angulation of the bone extremities. Standard management involves the use of a sling, cast, splint or brace and arm immobilisation for a few weeks. A coaptation splint may be used initially until the arm swelling has subsided and then replaced with a rigid cast or a brace after 1-2 weeks. A hanging arm cast may also be used to keep the arm bone in alignment.

Intramedullary rod

Surgical treatment

Surgery is required in significantly displaced, comminute humeral fractures as well as in open fractures. This treatment option will depend on the age, general health and the osteoporotic nature of the bone. Several approaches are available to repair the humeral shaft fracture including:

Intramedullary rod or nail involves the use of a metal rod introduced in the canal of the bone shaft that is fixed on the outer bone extremities with screws. The rod can be inserted either from the proximal or distal end of the humerus

Open reduction and internal fixation (ORIF)

Open reduction and internal fixation (ORIF) consists of accessing the humerus with a large skin incision to allow the insertion of a metal plate along the fracture length, which is fixed with multiple screws.

External fixation of a comminuted humerus shaft fracture

External fixation with percutaneous screws is a temporary fixation of the humerus fracture with screws inserted through the skin to maintain the anatomical bone alignment while the fracture is healing. This procedure is often followed by permanent internal fixation within 14 days after the injury. This treatment is used in situations where an immediate internal fixation cannot be performed, eg. multiple injured patients or severe soft tissue damage. In rare cases the external fixator remains in place until the fracture has healed completely.

Complication: malunion of the bone extremities


With either conservative or surgical treatments, complications after the repair of humerus shaft fracture can occur. The most frequent complications include:


Non-union of the fracture (when the gap between the bone extremities is not closed)

Mal-union when the fracture heals with abnormal bone alignment

Temporary damage to the radial nerve

Vascular damage

Joint stiffness of the shoulder and elbow

Physiotherapy begins following stabilisation of the humeral fracture


A humeral shaft fracture requires approximately three months to heal. Major attention is drawn to restore the function of the elbow and shoulder joints that may have stiffened during the immobilisation phase. Rehabilitation will begin as soon as the fracture has become stable as recommended by the orthopaedic surgeon. Physical exercise is gradually increased in intensity to regain strength, flexibility and range of movement of the elbow and shoulder. The prognosis of humeral shaft fracture is usually good. Standard rehabilitative therapy includes:


Joint mobilisation


Dry needling


Activity modification advice

Return to sport/work plan

Postural taping

Monitoring osteoporosis in post-menopausal women to prevent fractures


The main preventative measures aim at reducing the risk of falls and use a protecting gear during contact sports, biking/motor biking to protect the arm in case of collision and accident. Other common preventive strategies include:

Postural taping

Osteoporosis treatment

Use of walking devices to improve stability and avoid falls in elderly patients

Modification of physical activities

Regular physical exercise to maintain muscle strength, joint flexibility and correct posture