Elbow arthritis can be divided into two primary etiologies – osteoarthritis and rheumatoid arthritis. Secondary causes of elbow arthritis include trauma, hemophilia, joint infection, and crystalline arthropathy. The most common symptoms associated with elbow arthritis include painful range of motion, decreased range of motion, and weakness.
Patients with primary rheumatoid arthritis typically present with complaints at multiple joints, even if one joint is more greatly affected than another. Rheumatoid patients have pain throughout their arc of motion, anywhere from full flexion to extension. Early morning stiffness starting in the smaller joints of the hand and then progressing to the elbow is common in rheumatoids.
In contrast, patients with osteoarthritis present with pain typically in one portion of the range of motion where the osteophytes impinge on surrounding soft tissues or bony structures. It is important to isolate which portion of the arc of motion is painful and therefore determine where the impingement is occurring. For arthritic changes of the ulnohumeral joint, pain would occur during flexion and extension, while radiocapitellar involvement would affect supination and pronation. It is much more common for the arthritic elbow, regardless of etiology, to be stiff, rather than unstable.
If the patient has numbness and tingling in the distribution of the ulnar nerve (ring and small fingers of the hand), consider the possibility that the arthritic degeneration of the joint is affecting the ulnar nerve at the cubital tunnel.
The incidence of primary osteoarthritis is less than 2% of the general population. Typically patients have used the affected arm for heavy labor, significant weightlifting, or been a throwing athlete. Rheumatoid arthritis is more rare, affecting 0.5%-1% of the general population, with a 2:1 female to male ratio. 20%-65% of patients diagnosed with rheumatoid arthritis have elbow involvement. End stage symptoms have become less common with the advent of improved disease modifying medications.
Pathology and pathophysiology
For primary osteoarthritis, there is overload of one portion of the articular surface of the ulnohumeral joint, or the radiocapitellar joint. These surfaces develop new bone formation as osteophytes, which may also contribute to tightening of the capsule, joint contracture, and resultant stiffness. In early OA the osteophytes occur on the tips of either the olecranon or the coronoid, therefore impinging in their respective fossae during terminal extension or flexion.
Rheumatoid arthritis, much like in other parts of the body results from an inflammatory reaction to native joint architecture. The inflammatory pannus eats away at normal articular cartilage and subchondral bone and can cause capsular hypertrophy. At times when the pannus is excessive, the medial and/or lateral collateral ligaments of the elbow may be degraded leading to a degree of instability.
The differential diagnosis would include any etiology leading to elbow pain with range of motion. This would include tendon pathology about the elbow, such as medial or lateral epicondylitis, distal biceps tendiopathy or tendon rupture, and triceps tendonitis. Additionally, ligamentous injury to the ulnar collateral ligament or lateral collateral ligament may cause instability leading to painful range of motion. Ulnar neuropathy can lead to significant pain with range of motion, especially because the ulnar nerve travels a great distance with elbow flexion and extension. Elbow trauma including fractures, dislocations and subluxations can cause painful range of motion and stiffness; however the onset is acute as opposed to the chronic nature of arthritis.
The etiology, as mentioned above, of osteoarthritis is typically overuse with bearing heavy loads, or post-traumatic in nature. Septic arthritis can cause articular degeneration. Rheumatoid arthritis is due to the autoimmune destruction of the synovial lining and articular cartilage.
Radiographic and laboratory findings
Radiographic findings in osteoarthritis typically show preservation of the central portion of the ulnohumeral articulation with osteophyte formation and joint space narrowing at the periphery of the joint, either medially, laterally, anteriorly, or posteriorly. If the arthritic changes are post-traumatic in nature, displacement of the radial head with intraarticular step-off may indicate the reason for the arthritic changes. CT scans provide three dimensional views to visualize loose bodies from fractured osteophytes.
Rheumatoid imaging reveals symmetric joint space narrowing, periarticular erosions, and eventual subluxation, dislocation, fragmentation, fracture, and ankylosis. Rheumatoid patients typically have elevated autoantibodies to immunoglobulin G (IgG). Other elevated serum markers include rheumatoid factor (RF), anticitrullinated protein antibody (ACPA), C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR).
Risk factors and prevention
Prevention for osteoarthritis is primarily focused on anatomic reduction of intraarticular fractures with open reduction and internal fixation. If early arthritic changes are found in heavy laborers or weightlifters, they should be educated to limit the exacerbating activities and focus on range of motion exercises.
Early diagnosis and treatment with disease modifying antirheumatic drugs (DMARDs) is the mainstay of prevention for rheumatoid arthritis.
Treatment for osteoarthritis focuses primarily on the main complaint of the patient. Initial treatment involves conservative measures, such as anti-inflammatory medications and activity modification. Following this, if the primary complaint is stiffness without pain, a joint release, either open or arthroscopic can be performed. If there is pain at the extremes of motion secondary to osteophyte formation, the offending osteophytes can be debrided either arthroscopically or in an open fashion. If the primary area of pathology is at the radiocapitellar joint and there is no instability at the elbow or the wrist a radial head excision may be performed, either open or arthroscopically. Radial head arthroplasty may be performed if there is a concern for proximal migration of the radius or increasing wear at the ulnohumeral articulation. For younger patients who have more significant symptoms than can be addressed with debridement an interpositional arthroplasty or arthrodesis may be performed. The interpositional arthroplasty involves using a tendon allograft and placing it within the articulating surface of the ulnohumeral joint to provide a cushion and more padding than the worn down articular surfaces can provide. Arthrodesis is when the ulnohumeral joint is fused so there is no flexion or extension possible at the elbow joint. End stage disease in the elderly, low demand patient is treated with total elbow arthroplasty. The primary concern with this procedure is the limitations on weight lifting (nothing greater than 10 lbs), whereas these limitations do not exist with interposition arthroplasty.
Rheumatoid treatment initially focuses on maintenance of elbow range of motion, typically under the guidance of an occupational therapist. Medical treatments such as DMARDs (methotrexate, sulfasalazine, and hydroxychloroquine) and tumor necrosis factor alpha (TNF-?) inhibitors (etanercept, infliximab, adalimumab) used in concert have helped slow disease progression. Surgical treatment is similar to that of osteoarthritis and includes synovectomy, interposition arthroplasty, and total elbow arthroplasty.
Open and arthroscopic debridement have been shown to increase the total arc of motion by 20 to 30 degrees. Studies have shown significant improvements in pain and range of motion. Early treatment with DMARD and TNF-? has been shown to prevent radiographic progression of rheumatoid arthritis over a 5 year period. At 6 years status post interposition arthroplasty the arc of motion improved 47°. Total arc of motion after total elbow arthroplasty improved from 69° preoperatively to 107°postoperatively.
The main complication associated with interposition arthroplasty is instability of the elbow joint with range of motion. Complications associated with total elbow arthroplasty include infection, osteolysis, early loosening of the implant, and nerve injury (median and/or ulnar). The revision rate for total elbow arthroplasty for osteoarthritis averages 9% and for rheumatoid arthritis ranges from 5%-21%. The revision rate was 3 times higher for patients under 65 years old treated with total elbow arthroplasty compared with those older than 65 years old.
Stiffness, painful range of motion, crepitance, instability, osteophytes, joint space narrowing, osteosclerosis.
Skills and competencies
Students should be able to identify an elbow with decrease range of motion, palpate crepitance with range of motion, identify which side of the elbow is the symptomatic side (radial or ulnar), and perform a Tinel test at the cubital tunnel to evaluate for ulnar neuropathy.