Wrist Arthritis

Etiology

According to the American academy of orthopedic surgeons (AAOS), three primary types of arthritis affect the human wrist: osteoarthritis, rheumatoid arthritis, and post-traumatic arthritis.[1]

1. Osteoarthritis (OA): This is a common cause of wrist pain in the elderly population, although it can affect any age group. Aging, hereditary factors, high BMI, joint anatomy, and gender are the risk factors linked to the development of osteoarthritis. In young adults, it usually happens secondary to preceding joint injury.
2. Rheumatoid arthritis (RA) is an inflammatory condition that affects the peripheral joints symmetrically. The exact etiology of rheumatoid arthritis remains unknown, but it is thought to be multifactorial.[2][3]
3. Post-traumatic arthritis develops because of traumatic events such as injuries to the ligaments or fractures of the wrist bones. Despite adequate treatment, damage to the bones increases the risk of developing arthritis over time.[4] It usually affects the victim many years after the initial injury.

Other causes of wrist arthritis are infection (septic arthritis), crystal-induced arthritis, reactive arthritis, and systemic diseases like sarcoid arthropathy, myelodysplastic, and leukemic disorders.

Epidemiology

Although the wrist is not a weight-bearing joint, it has a significant function in day-to-day activities, and that predisposes it to trauma and arthritis. On an estimate, one in seven persons in the United States has wrist arthritis (13.6%). The prevalence of rheumatoid arthritis affecting the wrist is 2.5 million people in the United States and approximately 75% in the general population. Gout affects the wrist in 0.28% of the population.[5]

Pathophysiology

The pathophysiology of wrist arthritis depends on the type of arthritis affecting the wrist. Here, we are briefly mentioning the pathophysiology of the most common types.

• Osteoarthritis, a disease previously thought to be due to wear and tear, has a more complex pathogenesis. Some of the factors involved are biomechanical factors, proteases like several matrices metalloproteinases (MMPs), cysteine proteinases, serine proteinases, and proinflammatory cytokines.
• Rheumatoid arthritis results from a complex interaction between genetic and environmental factors that leads to a breakdown of immune tolerance and synovial inflammation.
• In post-traumatic osteoarthritis, the mechanics of the wrist and ligaments will change, and loading factors are redirected or misdirected, resulting in damage to cartilage, and that promotes osteoarthritis.

History and Physical

History: The most common manifestation of wrist arthritis is pain that is diffuse in the whole wrist joint. The character of the pain varies depending on the type of arthritis. For example, pain due to osteoarthritis is worse with joint use and is relieved by rest. Pain due to rheumatoid arthritis is often associated with stiffness, which is worse in the morning and gets better as the day goes on. Symmetric involvement of the joints is also more common in rheumatoid arthritis. Other than pain, swelling is an important feature of arthritis. Swelling can be due to effusion or synovial hypertrophy.

Redness and warmth of the joints, along with swelling in a non-traumatic wrist joint suggest inflammation (inflammatory arthritis) or infection (septic arthritis). Patients may also present with limitations in range of motion and can even feel weakness.

Constitutional symptoms like fevers, chills, fatigue, night sweats, and weight loss suggest a systemic cause. The systemic cause could be a systemic rheumatological disease, malignancy, or septic arthritis.

Physical examination includes inspection, palpation, range of motion, and special tests.

Inspection: Swelling and deformities are the two important findings associated with arthritis. Regarding swelling, it is important to distinguish between a joint effusion from tenosynovitis or a localized mass. Arthritis usually produces a diffuse circumferential swelling. Chronic inflammation in diseases like rheumatoid arthritis can cause deformities like volar subluxation of the carpus, carpal collapse, and radial deviation of the carpus. It can also result in instability with dorsal subluxation of the ulnar head, which causes "piano key" like movement with downward pressure.

Palpation: Palpation helps in identifying the specific area affected by the underlying pathology. The wrist is best palpated in slight flexion and feeling the dorsal surface of the wrist with the thumb while supporting the wrist with the fingers of both hands. Dorsal instability is a sign of joint effusion. Instability can be tested by looking for transmission of pressure from one hand placed at one side of the joint to the second hand placed on the opposite side.

Range of Motion: Providers should test the active range of motion first. They should attempt if there is any limitation to look for any improvement. The range of motion tested at the wrists is flexion, extension, radial, and ulnar deviation. The normal range of flexion is 65 to 80 degrees of flexion, 55 to 75 degrees of extension, 30-45 degrees of ulnar deviation, and 15 to 25 degrees of radial deviation.

Special tests: Tinel sign, Carpal compression test, Phalen test, Finkelstein test, etc. in excluding causes other than arthritis in a patient with wrist pain.

A wrist joint examination is complete only after an examination of the elbow (joint above) and the hand joints (joint below).

Evaluation

Evaluation of wrist arthritis begins with a complete history, including the onset of symptoms, location, nature, duration, aggravating, and easing factors. If the pain is chronic, triggers causing recent exacerbations should be enquired. Apart from history, a complete physical examination, as outlined above, will guide the provider in ordering appropriate diagnostic tests.

Radiographs of the Joint: Conventional radiography is the most widely used imaging modality and allows for the detection of bone pathologies like fracture, erosions, osteonecrosis, osteoarthritis, or a juxta-articular bone tumor. Characteristic features of osteoarthritis include marginal osteophytes, joint space narrowing, subchondral sclerosis, and cysts. The presence of chondrocalcinosis, a radiologic feature of calcium pyrophosphate deposition disease, increases suspicion for pseudogout.

Providers have also used ultrasonography with varying success. It is unhelpful in checking the bones or deep parts of the joints and is operator-dependent, but it might show OA-associated structural changes, osteophytes, crystal deposition and is also useful for detecting synovial inflammation, joint effusion, and erosions.[6][7]

Laboratory Tests- Leukocytosis supports the possibility of infection. Cultures of blood, urine or other possible primary sites of infection are mandatory when a septic joint is being considered. Elevated inflammatory markers like ESR or CRP, although nonspecific, suggest an infectious or inflammatory process. Rheumatoid factor and anti-CCP (cyclic citrullinated peptide) antibodies should be ordered if there is clinical suspicion for rheumatoid arthritis. A serum uric acid level is often ordered by providers when gout is suspected, but it is not reliable as it may be spuriously elevated in acute inflammatory conditions or acutely diminished during a true gout attack.

Synovial Fluid Analysis: A joint arthrocentesis and synovial fluid analysis are mandatory if an infection is suspected. Such patients should also be started on empiric antibiotic therapy as soon as possible after the synovial fluid sample is obtained. The fluid analysis is also helpful in diagnosing crystal-induced arthritis. The sensitivity of polarizing microscopy in identifying birefringent crystals approaches 90% in acute gout and 70% in acute pseudogout. The degree of elevation of synovial fluid WBC count can be useful in differentiating inflammatory from non-inflammatory causes of arthritis.

Treatment / Management

Like the pathogenesis, treatment of wrist arthritis greatly depends upon the type of arthritis.

Osteoarthritis: Non-surgical management includes acetaminophen, NSAIDs, and other analgesic medications, avoiding activities causing exacerbation of the pain, immobilizing joints with wrist splints, especially during daytime and during activities, physical therapy, and local corticosteroid injections. Systemic steroids have no role and should be avoided. Pills containing hyaluronic acid and glucosamine are ineffective and have a placebo effect.[8](B3)

Rheumatoid Arthritis (RA): Disease-modifying antirheumatic drug (DMARD) therapy is the cornerstone in the management of RA. Anti-inflammatory therapies, including systemic and intraarticular glucocorticoids and NSAIDs, are used primarily as adjuncts for temporary control of disease activity in patients in whom treatment is being started with DMARDs or during disease flares and modification of the DMARD regimen. Methotrexate, hydroxychloroquine, sulfasalazine, and leflunomide are the major traditional DMARDs. Biologic agents like anti-TNF-alpha agents, including etanercept, infliximab and adalimumab, tocilizumab (IL-6 inhibitor), tofacitinib (JAK inhibitor), and rituximab (anti-CD-20 monoclonal antibody) are all used for the treatment of RA.

Surgical treatment is indicated when disabling pain emerges despite conservative and non-surgical treatments. There are many surgical approaches available, like wrist denervation, ulnar resection (removes the pressure from wrist), or synovectomy, but the ones used most often include proximal row carpectomy, wrist fusion, and wrist replacement (AAOS, 2018).

Proximal row carpectomy involves the removal of the three carpal bones close to the forearm to ease pain and sustain wrist motion. Fusion or arthrodesis is a welding process that removes the damaged cartilage and attaches wrist bones to make sure they heal as a single and solid bone that does not cause pain. Fusion will reduce the range of motion but eliminate the pain. Arthrodesis can be limited or total. In wrist replacement, the surgical procedure involves the removal of the damaged wrist cartilages and bones and replacement with plastic or metal joints. The goal is to restore function, regain range of motion, and reduce the pain. The implants have not resulted in gratifying results such as those with knee or hip replacement.[9][10][11][12]

Differential Diagnosis

Apart from the causes discussed above, the important differentials to consider are Lyme arthritis, sarcoid arthropathy, peripheral spondyloarthritis, and atypical infections like mycobacteria and fungi.

Besides wrist arthritis, one should consider the following differentials during the evaluation of wrist pain.

• Peri-articular: Tenosynovitis including De Quervain tenosynovitis, pigmented villonodular tenosynovitis, acute calcific peri-arthritis
• Bone lesions: Fractures, neoplasms, infection, osteonecrosis like Kienbock disease (avascular necrosis of the lunate bone) and Preiser disease (scaphoid bone)
• Neurologic: Nerve entrapment syndromes, particularly carpal tunnel syndrome and ulnar nerve entrapment in the Guyon canal
• Vascular: Scleroderma and occupational vibration syndromes
• Referred Pain: Cervical spine disorders and reflex sympathetic osteodystrophy

Prognosis

The prognosis of wrist arthritis is cause specific. Osteoarthritis or repetitive use injury arthritis may do well with conservative management or surgical treatment. Autoimmune causes may have a poorer prognosis based on the severity of the disease and the efficacy of disease-modifying agents to control the inflammation. Poor control of wrist pain may lead to progressive debility and morbidity in the elderly, leading to poor functional status. 

Complications

The complications of wrist arthritis are mostly due to the various surgical treatments of the disease. Continued wrist pain due to a nonunion or fibrous union is a potential complication of fusion surgeries. As with all orthopedic surgical procedures, there is a risk of prosthetic infection, neurovascular injury as a complication of the procedure itself, and implant failure or loosening.