THE CLINICAL SYNDROME

• Avascular necrosis, also known as osteonecrosis, of the glenohumeral joint is a commonly missed diagnosis.

  • This condition is also known as osteonecrosis.

• Because of the fragile blood supply of the articular cartilage, which is only 1.0 to 1.2 mm thick at the center of the humeral head, the glenohumeral joint, like the scaphoid, is extremely susceptible to this disease.

• This makes the glenohumeral joint similar to the scaphoid.

• Because of how easily this blood supply can be disrupted, the proximal portion of the bone is frequently deprived of nutrition, which can eventually lead to osteonecrosis.

• Except in cases where it is a secondary complication of collagen vascular disease, avascular necrosis of the glenohumeral joint typically affects people in their fourth and fifth decades.

• Men are more likely to suffer from avascular necrosis of the glenohumeral joint than women.

• In approximately half to a majority of cases, both sides of the body are affected.

• Avascular necrosis of the glenohumeral joint can be caused by a number of risk factors.

• Trauma to the joint, use of corticosteroids, Cushing's disease, abuse of alcohol, and connective tissue diseases such as systemic lupus erythematosus, osteomyelitis, human immunodeficiency virus infection, organ transplantation, hemoglobinopathies such as sickle cell disease, hyperlipidemia, gout, renal failure, pregnancy, and radiation therapy involving the femoral head are all examples of these risk factors.

• Patients who have avascular necrosis of the glenohumeral joint typically experience pain in the area of the affected glenohumeral joint or joints, and this pain may radiate into the proximal upper extremity and shoulder.

• Patients frequently report that they experience a catching sensation in the affected glenohumeral joint or joints when they move their arms through their full range of motion.

• The pain is severe and throbbing in nature.

• As the disease progresses, there is a reduction in the patient's range of motion.

SIGNS AND SYMPTOMS

• Pain is felt upon deep palpation of the glenohumeral joint in patients who have been diagnosed with avascular necrosis of the glenohumeral joint.

• This is discovered during a patient's physical examination.

• Both active and passive ranges of motion have the potential to make the pain worse.

• When the examiner performs a range of motion on the glenohumeral joint, they may also hear or feel a clicking or crepitating sound.

• Inevitably, the range of motion will be restricted.

TESTING

• Plain radiographs are recommended for all patients who present with avascular necrosis of the glenohumeral joint.

• This is done to rule out any underlying occult bony disease, as well as to identify sclerosis and fragmentation of the humoral head.

• Despite the fact that plain radiographs are notoriously unreliable early in the course of the disease, plain radiographs are indicated in all patients who present with this condition.

• The clinical presentation of the patient may indicate the need for additional testing, which may include a complete blood cell count, uric acid, sedimentation rate, and testing for antinuclear antibodies.

• When other potential causes of joint instability, such as infection or tumor, are suspected in a patient, a magnetic resonance imaging (MRI) scan of the glenohumeral joint is recommended.

• This includes patients in whom the patient is suspected of suffering from avascular necrosis of the glenohumeral joint.

• In some cases, the administration of gadolinium, followed by postcontrast imaging, can help determine whether or not the blood supply is adequate.

• Contrast enhancement of the glenohumeral joint is a positive indicator of the patient's prognosis.

• If you suspect that you have cervical radiculopathy and brachial plexopathy at the same time, then you should get an electromyography.

• A very careful intraarticular injection of the glenohumeral joint with a small volume of local anesthetic provides immediate relief from the patient's pain and helps demonstrate that the glenohumeral joint is indeed the source of the patient's pain.

• Eventually, patients who suffer from avascular necrosis of the glenohumeral joint will need to have their entire joints replaced.

• However, newer joint preservation techniques are becoming more popular in younger patients who engage in more physical activity.

• This is due to the fact that total shoulder prostheses have a relatively short life expectancy.

DIFFERENTIAL DIAGNOSIS

• It is possible for avascular necrosis of the glenohumeral joints to coexist with other conditions, such as arthritis and gout of the glenohumeral joint, joint bursitis, and tendinitis.

• These conditions can make the patient's pain and disability worse.

• Avascular necrosis of the glenohumeral joint can cause pain that is similar to that caused by other conditions, such as labral tears, ligament tears, bone cysts, bone contusions, and fractures.

• Occult metastatic disease can also cause pain that is similar to that caused by avascular necrosis.

TREATMENT

• A combination of nonsteroidal anti-inflammatory drugs (NSAIDs) or cyclooxygenase-2 (COX-2) inhibitors and decreased weight bearing of the affected glenohumeral joint should be used as the initial treatment for the pain and functional disability associated with avascular necrosis of the glenohumeral joint.

• The application of heat and cold to specific areas of the body may also be beneficial.

• Patients who do not respond to these treatment modalities may benefit from the administration of a local anesthetic through an injection into the glenohumeral joint as the next step in the treatment process to provide palliation of acute pain.

• The intraarticular injection of platelet-rich plasma and/or stem cells may provide some resolution of the osteonecrosis of the femoral head, so this new treatment may be worthy of consideration in patients suffering from avascular necrosis of the glenohumeral joint.

• Clinical reports suggest that the resolution of the osteonecrosis of the femoral head may provide some resolution.

• Exercises that are too strenuous for the patient should be avoided because doing so will make their symptoms worse.

• In the end, the most effective treatment for total joint arthroplasty is surgical repair in the form of total joint replacement.

COMPLICATIONS AND PITFALLS

• If significant avascular necrosis of the glenohumeral joint is not treated surgically, the typical outcome is ongoing pain and disability, and in the majority of patients, this results in ongoing damage to the glenohumeral joint.

• If the clinician pays close attention to the details, uses only a small amount of local anesthetic, and avoids high injection pressures that could cause the joint to sustain additional damage, then the injection of the joint with local anesthetic is a technique that is relatively safe.

• Infection is yet another potential risk associated with this method of injection.

• If the aseptic procedure is carried out in a meticulous manner, it is expected that this complication will occur only very infrequently.

• After receiving this type of injection, approximately one quarter of patients experience an increase in the pain for a brief period of time.

• Patients should be informed that this is a possibility.