Bony injuries to the humeral head are referred to as humeral head fractures. This type of injury mainly occurs after falls on the outstretched arm and on the shoulder.
It accounts for around 4 to 5 percent of all fractures. In addition, the humeral head fracture is the most common fracture of the shoulder girdle, accounting for 47 percent of all fractures.
Risk factors for humeral head fractures are advanced age and the presence of osteoporosis. As the population is getting older and the incidence of osteoporosis is increasing, the number of humeral head fractures is also rising continuously.
On average, women are affected 2 to 3 times more frequently than men.
Together with the glenoid cavity, the humerus forms the main movable part of the shoulder joint.
The bone of the humeral head is considerably larger than the glenoid cavity. This enables the greatest possible mobility in the shoulder joint. However, this means that the joint is not as strong as the hip joint, for example, where the femoral head is almost completely surrounded by the acetabulum.
The shoulder joint is therefore mainly supported by the attached soft tissue, i.e.
- tendons,
- muscles and
- ligaments
stabilized. This knowledge is essential for understanding the following descriptions of humeral head fractures (fractures of the humeral head) and their treatment.
The following diagram shows the basics of anatomy in simplified form:
- Humeral head/Tuberculum majus
- Humeral head: articular cartilage
- glenoid cavity
- Clavicle
- Acromion
- Humeral shaft
- Acromioclavicular joint
Various structures of the humeral head can be injured in an accident. These injuries differ considerably in their diagnosis, treatment and long-term outcome. It is therefore not possible to consider all humeral head fractures together.
Depending on
- the number of fragments produced in the humeral head fracture,
- the extent of the fragment displacement and
- the height of the fracture
the injury is divided into different types. Different procedures are used to treat each type.
A distinction is made between type 0 fractures as non-displaced "single-part fractures" and type A fractures. The latter are two-fragment fractures with avulsion of the large tuberosity (greater tuberosity) or the small tuberosity (lesser tuberosity).
There are also type B fractures, which occur in the surgical neck and can have 2 to 4 fracture fragments. Type C fractures occur in the anatomical neck. Here, too, there may be 2 to 4 fracture fragments.
Type X fractures are anterior or posterior dislocation fractures (dislocation of the shoulder joint with accompanying bone fracture). After shoulder joint reduction (re-dislocation), this fracture is also classified according to type A to C.
We also differentiate between comminuted head fractures (so-called head splitting and impression fractures).
The main symptom of a humeral head fracture is pain as well as limited functionality and mobility.
In the case of a humeral head fracture, the affected person holds the humerus in a protective position to minimize pain. There is usually more or less pronounced swelling of the shoulder joint.
This is followed by the appearance of a bruise (hematoma) in the area of the affected shoulder. The hematoma may spread to the elbow.
Confirmation of a suspected humeral head fracture is made possible by an X-ray.
Computed tomography(CT) is used as a further examination for complex fractures of the humeral head. A CT scan also helps to decide whether or not surgical treatment of the humeral head fracture is necessary.
Different stages of osteoporosis, in which the bone density decreases © crevis | AdobeStock
The aim of treatment is to maintain the free range of motion of the shoulder joint without pain, depending on the patient's age and functional requirements.
The treatment concept must therefore be individually adapted to the patient's requirements.
Treatment principles for a fracture of the humeral head (humeral head fracture)
60 to 85 percent of humeral head fractures are type 0 fractures. The non-displaced or only slightly displaced humeral head fracture (type 0 fracture) is not operated on.
This type of fracture is "splinted" by the periosteum, the joint capsule and the muscles. Immobilization in a tubular bandage for 7 to 14 days is therefore sufficient until the pain subsides.
Early functional exercise treatment is important to prevent the shoulder joint from stiffening. After around 6 to 8 weeks, the bone fracture will be solid again.
Artificial joint replacement
Fracture types A to C, type X and humeral head comminuted fractures result in
- severe malalignment,
- restricted movement and
- pain.
Surgery is necessary to restore the original condition of the humeral head as far as possible. Different materials are used to stabilize the fracture, depending on the type of fracture. A fracture can be stabilized using
can be stabilized.
In some cases, it is also advisable to replace the humeral head with a shoulder prosthesis(artificial joint replacement). The prerequisite for this is that
- due to the severity of the injury, surgery to preserve shoulder joint function is not possible, or
- the vessels supplying the humeral head are destroyed, so that the probability of the humeral head dying off is very high.
In recent years, special fracture prostheses have been developed for this type of joint replacement. They can be individually adapted to the fracture.
The height of the prosthesis head can be adjusted to compensate for any loss of height caused by the fracture. In addition, the fracture prosthesis has special features to refix the torn rollers(major and minortuberosities ) to the prosthesis in an anatomical position. This is important, as the tendons of the rotator cuff attach to the rollers.
The humeral comminuted fracture occupies a special position. If more than 40 percent of the joint surface is destroyed in this fracture, joint surface replacement using a humeral head prosthesis is also indicated here.
In some cases, a shoulder prosthesis is used © bilderzwerg | AdobeStock
Treatment of the different types of humeral head fractures
One problem with fractures in the shoulder area is the rapid stiffening of the shoulder. For this reason, prolonged immobilization in a cast or bandage should be avoided in the case of a humeral head fracture.
The treatment of the different fractures of the humeral head varies greatly depending on the type. The individual humeral head fractures and their treatment are therefore discussed below.
Humeral head fracture with avulsion fracture of the greater tuberosity
In a humeral head fracture with avulsion of the greater tuberosity, the large bony protrusion to which the rotator cuff has attached is blown off.
The accident mechanism is usually a direct impact trauma or adislocation of the shoulder. The dislocated part of the tuberosity typically remains in place (see Figure 1).
After the shoulder has been re-dislocated, the bone either settles well into its original position or it remains in a malposition (see Figure 2).
In the latter case, a minor operation is necessary. The bone fragment is returned to its original position. It is fixed in place with screws or strong stitches until it has healed. This usually takes around six weeks.
During this time, the follow-up treatment involves guided movements without the development of force. A final X-ray check can then document the success of the healing process.
Active muscle and movement development is then necessary.
Subcapital humeral head fracture
A subcapital humeral head fracture is a fracture that runs through the entire circumference of the humeral head. The red lines in the diagram below illustrate the different fracture lines that can run through the humeral head.
These injuries are generally referred to as humeral head fractures or humeral head fractures.
The treatment of these injuries depends on the extent of the displacement of the bone fragments.
If the bone fragments are only slightly displaced, treatment can be carried out without surgery. In this case, immobilization in a Gilchrist bandage for 3 weeks is sufficient. This is followed by physiotherapy with guided movements out of the bandage for 6 weeks. This therapy is also called "conservative" because no surgery is performed.
The healing process must be monitored at regular intervals using x-rays. Fractures can shift during this time. This is shown in the following example:
Comminuted humeral head fracture (head-split fracture)
Sometimes the humeral head is so shattered that the blood supply to the individual pieces of bone is destroyed. The bone can then no longer heal and must be replaced by an artificial joint.
Whether the humeral head can still be saved after a comminuted humeral head fracture depends on a number of factors. The basis of bone healing is a sufficient blood supply to the bone fragments. Without blood, there is no healing. The decision is therefore significantly influenced by all factors that affect the blood supply.
Another important factor is the degree of osteoporosis. This bone atrophy leads to the bone becoming thinner on the inside and less able to bear weight. This also makes it considerably more difficult to anchor screws in severely osteoporotic bone.
The decision as to whether the humeral head can be preserved or needs to be replaced also depends on the following factors:
- The patient's age, as the degree of osteoporosis is strongly influenced by this
- The patient's general state of health
- Heavy smokers already have poorer blood circulation from the outset.
- Chronic diseases such as dialysis, cortisone therapy and diabetes worsen the blood flow.
With careful consideration, reconstruction can be attempted in young, healthy and athletic patients. However, there is a higher risk that the reconstruction will not be successful and a prosthesis will be necessary. Patients must be aware of this risk.
If the procedure is successful, the joint can recover.
The surgical technique for humeral head fractures has improved revolutionarily in recent years thanks to new so-called stable-angle implants. As a result, it is now possible to reconstruct even the most severe fractures and treat them without an artificial joint. The surgeon's experience is crucial here.
Follow-up treatment must be individualized. Also
- the duration of the inability to work and
- and the time of resumption of sport-specific training
depends on the injury and the chosen surgical procedure.
The prognosis for humeral head fractures depends primarily on their complexity. As the number of fragments increases, the probability of being able to fully restore shoulder function decreases.
Other decisive factors for the chances of recovery from a humeral head fracture are
- On the one hand, the age of the patient,
- on the other hand, pre-existing, wear-related, bony or muscular restrictions.
The risks of surgery are
- Risk of infection and wound healing disorders
- nerve lesions
- Failure of bone healing with formation of a false joint
- Implant failure (breakage of a screw or plate)
- Functional impairment of the shoulder
In summary, the number of humeral head fractures has increased significantly in recent years. The treatment of a humeral head fracture depends on the degree of displacement and the patient's state of health.
In the case of surgery, the clinic should have as much experience as possible with cases of this type. The success of the treatment depends largely on the surgical procedure.
Images: Radiological images were kindly provided by Dr. Stefan Wirth.
Graphics: by Ms. Hella Thun
