Shoulder Fractures

Any of the bony components of the shoulder may fracture as a result of a wide variety of injuries. The Proximal or Upper Humerus and Clavicle are most often injured. These fractures may require consideration of surgery based on factors such as the degree of displacement or fragmentation of the bone. Fractures of the scapula are not as common. Depending upon the fracture pattern scapula fractures tend to require surgery less often than fractures of the Humerus and Clavicle.

Clavicle Fractures

The Clavicle or Collar Bone is a bony strut that supports and connects the scapula to the rib cage and sternum. The clavicle helps to stabilise the scapula and the entire shoulder joint. A fracture of the clavicle may have an effect on the mechanics of the shoulder. Fractures most often occur in the middle of the clavicle (mid-shaft). Less often fractures may involve the outer or inner end of the clavicle. The location of the fracture may determine the best treatment options.

Fractures of the clavicle typically involve a high degree of force. This might include a direct blow to the shoulder or a fall onto the outstretched arm. Bicycle, motorcycle, and car accidents often result in clavicle fractures.  Sporting injuries are also a common cause of clavicle fractures.

A fractured clavicle may be obvious just from the clinical appearance of the shoulder. The pain may be severe. There may be a visible deformity or lump at the fracture site. On rare occasions, the sharp end of the bone at the fracture site may penetrate the skin. The affected shoulder may droop downwards.

X-rays will help to confirm the diagnosis. X-rays and sometimes CT Scans will also help to monitor the healing process.

Many non-displaced or minimally displaced fractures will unite with non-surgical treatment. They may simply require pain management. Once the surgery pain has eased and healing is seen on X-rays a graduated rehabilitation process can take place.

Humerus Fractures

The humerus is the bone of the upper arm which spans between the shoulder and elbow. The Head of the humerus forms to ball component of the shoulder joint. It articulates with the socket of the shoulder joint or glenoid. Nearby the head is 2 bony prominences. The larger one is the Greater Tuberosity. The other is the Lesser Tuberosity. The rotator cuff tendons are attached to the tuberosities. Just below the tuberosities, the bone narrows a little to blend with the main shaft of the humerus. The zone between the head and the shaft of the humerus is referred to as the Neck of the humerus.

Fractures of the upper or proximal humerus are common in elderly patients as a result of falls. Women with underlying osteoporosis are particularly prone to this injury. This type of fracture also occurs in younger patients but usually requires a greater degree of force, such as a fall from a height, bicycle, motorcycle and car accidents. Fractures of the humerus may also occur in combination with a dislocation of the shoulder

Types of Proximal Humerus Fractures

Fractures may involve any of these 4 main components of the proximal humerus or combinations thereof. Fractures may also occur in the main shaft of the upper humerus. The fractures can be classified on the basis of:

• The Number of Components of the humerus involved
• Degree of Displacement of fracture components
• Angulation of the bone fragments
• Interference to Blood Supply of the head of the humerus

Greater Tuberosity Fractures: This injury can occur as an isolated injury or in combination with a dislocation of the shoulder joint. Part of the rotator cuff is attached to the greater tuberosity of the humerus. If the bone fragment is displaced upwards and heals in that abnormal position it will interfere with the free passage of the rotator cuff under the acromion.

Lesser Tuberosity Fractures: This fracture is uncommon in isolation. It more often occurs in combination with fractures of other components of the upper humerus. If it heals in a displaced position there may be significant impairment of shoulder function.

Humeral Head Fractures: A fracture of the head of the humerus will involve will cause damage to the cartilage covering the ball component of the shoulder joint. It is a serious injury that often predisposes to arthritic wear of the shoulder joint in later life. Surgical restoration of the ball after a humeral head fracture is difficult. Sometimes the damage to the ball is sufficient to warrant the replacement of the damaged ball with a prosthesis.

Neck of Humerus Fractures: This type of fracture is also commonly referred to as a fracture of the Surgical Neck of the Humerus. A vast spectrum of fracture patterns can be observed. The better end of this injury spectrum would include un-displaced stable fractures which will heal well with conservative treatment and rehabilitation. At the other end of the scale, the fracture may be grossly displaced. It may also be in combination with fractures of other components of the upper humerus. Some of these fractures may compromise the blood supply to the head of the humerus. The injury may be severe enough to need a prosthetic joint replacement.