Osteonecrosis of the Elbow Joint
Osteonecrosis of the elbow joint is an often-missed diagnosis. Like the scaphoid bone of the wrist, the elbow joint is extremely susceptible to this disease because of the tenuous blood supply of the articular cartilage.
This blood supply is easily disrupted, often leaving the proximal portion of the bone without nutrition and leading to osteonecrosis.
A disease of the fourth and fifth decades, with the exception of patients with osteonecrosis of the elbow joint secondary to collagen-vascular disease, osteonecrosis of the elbow joint is more common in men. In younger patients, sickle cell disease is the most common cause of osteonecrosis of the elbow. The disease is bilateral in 45% to 50% of cases.
Factors predisposing to osteonecrosis of the elbow joint are listed in the below table. They include trauma to the joint; corticosteroid use; Cushing disease; alcohol abuse; connective tissue diseases, especially systemic lupus erythematosus; osteomyelitis; human immunodeficiency virus infection; organ transplantation; hemoglobinopathies, including sickle cell disease; hyperlipidemia; gout; renal failure; pregnancy; and radiation therapy involving the femoral head.
Predisposing Factors for Osteonecrosis of the Elbow Joint
|Trauma to the elbow joint|
|Connective tissue diseases, especially systemic lupus erythematosus|
|Human immunodeficiency virus|
|Hemoglobinopathies, including sickle cell disease|
|Sickle cell disease|
Patients with osteonecrosis of the elbow joint report pain over the affected elbow joint or joints that may radiate into the upper extremity. The pain is deep and aching, and patients often report a catching sensation with range of motion of the affected elbow joint or joints. Range of motion decreases as the disease progresses.
What are the Symptoms of Osteonecrosis of the Elbow Joint?
Physical examination of patients with osteonecrosis of the elbow joint reveals pain to deep palpation of the elbow joint. The pain can be worsened by passive and active range of motion. A click or crepitus also may be appreciated by the examiner when ranging the elbow joint. A decreased range of motion is invariably present.
How is Osteonecrosis of the Elbow Joint diagnosed?
Plain radiographs are indicated in all patients with osteonecrosis of the elbow joint to rule out underlying occult bony pathological processes and identify sclerosis and fragmentation of the osseous support of the articular surface. However, early in the course of the disease, plain radiographs can be notoriously unreliable; magnetic resonance imaging (MRI) reveals articular changes before significant changes are evident on plain radiographs. Based on the patient’s clinical presentation, additional testing, including complete blood cell count, uric acid level, erythrocyte sedimentation rate, and antinuclear antibody testing, also may be indicated. MRI and ultrasound imaging of the elbow joint is indicated in all patients thought to have osteonecrosis of the elbow joint; if other causes of joint instability, infection, or tumor are suspected; or if plain radiographs are nondiagnostic. Computed tomography (CT) may be useful in early diagnosis, especially with three-dimensional reconstruction. Administration of gadolinium followed by post-contrast imaging may help delineate the adequacy of blood supply, with contrast enhancement of the elbow joint being a good prognostic sign.
Electromyography is indicated if coexistent cervical radiculopathy or brachial plexopathy is suspected. A very gentle intraarticular injection of the elbow joint with small volumes of local anesthetic will provide immediate improvement of the pain and help demonstrate the nidus of the pain is in fact the elbow joint. Ultimately, total joint replacement will be required in most patients with osteonecrosis of the elbow joint, although newer joint preservation techniques are becoming more popular in younger, more active patients, given the short life expectancy of total shoulder prosthesis.
Coexistent arthritis and gout of the elbow joint, bursitis, and tendinitis may coexist with osteonecrosis of the elbow joints and exacerbate the pain and disability. Tears of the ligaments, bone cysts, bone contusions, and fractures may mimic the pain of osteonecrosis of the elbow joint, as can occult metastatic disease.
Initial treatment of the pain and functional disability associated with osteonecrosis of the elbow joint should include a combination of the nonsteroidal antiinflammatory drugs (NSAIDs) or cyclooxygenase-2 (COX-2) inhibitors and decreased weight bearing of the affected elbow joint or joints. Local application of heat and cold may be beneficial. For patients who do not respond to these treatment modalities, an injection of a local anesthetic into the elbow joint may be a reasonable next step to provide palliation of acute pain.
Ultrasound guidance may improve the accuracy of needle placement and decrease the incidence of needle-related complications. Vigorous exercises should be avoided because they will exacerbate the symptoms. Ultimately, surgical repair in the form of total joint arthroplasty is the treatment of choice.
Failure to surgically treat significant osteonecrosis of the elbow joint usually will result in continued pain and disability and in most patients will lead to ongoing damage to the elbow joint. Injection of the joint with local anesthetic is a relatively safe technique if the clinician is attentive to detail, specifically using small amounts of local anesthetic and avoiding high injection pressures, which may further damage the joint. Another complication of this injection technique is infection.
This complication should be exceedingly rare if strict aseptic technique is followed. Approximately 25% of patients report a transient increase in pain after this injection technique and should be warned of this possibility.
Osteonecrosis of the elbow joint is a diagnosis that is often missed, leading to considerable unnecessary pain and disability. The clinician should include osteonecrosis of the elbow joint in the differential diagnosis in all patients with shoulder joint pain, especially if any of the predisposing factors listed in the above table are present.
Coexistent arthritis, tendinitis, and gout may contribute to the pain and may require additional treatment. The use of physical modalities, including local heat and cold and decreased weight bearing, may provide symptomatic relief.
Vigorous exercises should be avoided because they will exacerbate the symptoms and may cause further damage to the wrist. Simple analgesics and NSAIDs may be used concurrently with this injection technique.