Detect rheumatoid arthritis in your patients with established criteria and radiography to determine chiropractic care protocols

Rheumatoid arthritis is a generalized connective tissue autoimmune condition characterized by significant inflammation of the synovial membrane. This inflammatory arthropathy affects between 1% and 3% of the adult, predominantly female population. The clinical expression of this disease commonly manifests by the time that the patient is 35 to 45 years old. If a patient has the onset of symptoms and signs of less than 16 years, this is classified as juvenile chronic arthritis and may involve the clinical and radiological appearances of several inflammatory arthropathies.

Figure 1: Bilateral anterior-posterior views of the knees demonstrating bilateral symmetrical involvement of the femorotibial articulation. In addition, a large subchondral cyst is noted in the midportion of the left (reading right) proximal tibia.

Rheumatoid arthritis is a condition classically known to affect the hands and feet, initially at the metacarpal and metatarsal articulations and in the carpus of the hand. However, as the condition progresses, it is quite possible for more extensive involvement of the smaller articulations in the hands and feet. The remaining joints may also be affected, including the knees, shoulders, cervical spine, and sacroiliac articulations.

This disease is not restricted to articulations. Rheumatoid arthritis may also affect a number of other systems, contributing to a worse prognosis for the patient if such involvement exists. Extra-articular manifestations include involvement of the heart, eyes, skin, nervous system, kidneys and vascular system.¹

General pathology. During the initial stages of the disease, the most prominent pathologic feature is that of acute synovitis. The synovial membrane is edematous, and there is vascular congestion. Accumulation of macrophages, polymorphonuclear leukocytes, erythrocytes, and later plasma and multinucleated giant cells is noted. The local collection of cells leads to increases in cell numbers and the potential for the synovial destructive process. These features also contribute to the ability to detect joint effusion and thickened synovium, which may enhance with intravenous injection of gadolinium using magnetic resonance imaging (MRI). During the inflammatory proliferation of the synovium, or pannus formation, regions within the articulations not covered with articular cartilage (the bare areas) begin to be destroyed, thus leading to periarticular or marginal erosions.

Clinical examination. Patients with rheumatoid arthritis present with common characteristic clinical features that have been established as criteria to assist in the diagnosis² (if 4 out of the following are present for more than 6 weeks): ): 1) morning stiffness for at least 1 hour; 2) swelling of three or more joints; 3) swelling of the wrist, metacarpal, or proximal interphalangeal joint; 4) symmetrical joint swelling; 5) hand x-rays typical of rheumatoid arthritis that must include erosions or unequivocal bony decalcifications; 6) serum rheumatoid factor by a method positive in less than 5% of normal subjects; and 7) characteristic histologic changes in rheumatoid nodules.

The nodules that form in subcutaneous locations at pressure points, such as the elbow, hands, or even visceral locations such as in the lungs, may suggest a poor prognosis. Histologically, they consist of a central area of fibrinoid necrosis surrounded by palisading epithelioid macrophages and other mononuclear cells.

Initially, patients may be fatigued, at times manifesting prior to the articular involvement. As the disease progresses and the articular destructive process continues, limitation of movement may occur, as well as the development of a variety of deformities, most especially of the hands and feet.³

Clinical investigations. Laboratory evaluations may be revealing and are recommended if there is a clinical history of rheumatoid arthritis. A full blood count can demonstrate normochromic normocytic anemia with an elevation of the erythrocyte sedimentation rate (ESR) and c-reactive protein (CPR) reflecting the activity of the disease. The leukocyte count may be normal or elevated.

Patients with rheumatoid arthritis may commonly, but not exclusively, have the presence of rheumatoid factor, a group of autoantibodies with anti-iImmunoglobulin G activity. In patients with rheumatoid arthritis, titers are usually much higher compared with the unaffected population. However, not all patients with rheumatoid arthritis have a positive rheumatoid factor.

Imaging findings. In the clinical setting, plain film radiography is usually performed as the preliminary study of choice.

In the initial stages of the disease, periarticular soft-tissue swelling and marginal erosions may be present. Remember to scrutinize the metacarphalangeal articulations in the hands. A special view called the ball-catchers view may be used to facilitate detection of the marginal erosions. As the hyperemia progresses, juxta-articular osteopenia may be noted.

Figure 2. Posterior-anterior radiograph of the right wrist demonstrating multiple erosive changes throughout the carpus and the carpometacarpal articulations. A uniform loss of joint space particularly affecting the 2nd and 3rd metacarpalphalangel articulations is also evident.

The radiographic appearance is most commonly a bilateral and symmetrical process with a uniform loss of joint space (Figure 1). With the evolution of the disease, characteristic involvement of the metacarpal and metatarsophalangeal articulations may be noted as well as erosive changes within the carpal, sometimes giving rise to the radiologic sign—the spotty carpal (Figure 2). The ulnar styloid process may be eroded due to the overlying synovial sheath of the extensor carpi ulnaris tendon—termed a rat-bite erosion.

For chiropractors, it is essential to determine the stability of the C1-C2 synovial-based articulation prior to treatment involving movement of the cervical spine. Patients should be assessed to determine the neurological status. If the examination is negative, evaluate the C1-C2 articulation using dynamic views to assess the atlanto-dental interspace—the normal upper limit in adults and children is 3 and 5 millimeters, respectively (Figure 3). If there is any doubt, an MRI will more clearly determine the presence of pannus tissue and evidence of instability, as well as additional complications of the spinal cord, including basilar impression/cranial settling.

Figure 3. Lateral spot radiograph of the upper cervical spine demonstrating a large atlantodental interspace, with erosive changes to the odontoid process, and on close inspection, tapering of the spinous processes can also be observed. Generalized osteopenia is present.

In the late stages rheumatoid arthritis, a variety of radiologic signs can be identified, and it is not possible to provide an exhaustive list. However, classic signs include elevation of the humeral heads as a result of rotator cuff injury and the subsequent unapposed action of the deltoid muscles. In addition, destruction of the distal clavicle may occur. Elsewhere, the cervical spinous processes may become resorbed and appear somewhat tapered. The sacroiliac articulations may be affected, most commonly demonstrating a unilateral sacroiliitis. The pelvis may demonstrate protrusio acetabulae in a bilateral and symmetric pattern.

Special imaging can also be used to evaluate patients. Ultrasound of the hand may reveal evidence of pannus formation or a focal synovitis in the early stages of the disease.⁴ An MRI can be useful to characterize the degree of articular involvement, as well as to determine the presence of additional complications such as those about the shoulder.⁵ The addition of contrast (gadolinium) intravenously in patients can determine the degree of synovial enhancement and hyperemia affecting an articulation.

There is not a particular technique that is advocated, but it is best to be gentle, with no forceful adjustments especially during the active stages of the disease. The most important thing to remember is to not adjust the cervical spine. CP

Michelle Wessely, BSc (Chiropractic), DC, DACBR, FCC (UK/Radiology) is the departmental head of Radiology at Institut Franco-European de Chiropratique, Paris, France. She completed her fellowship in musculoskeletal radiology at the Department of Osteoradiology, Veterans Affairs Healthcare Center, San Diego, under Donald Resnick, MD, professor of radiology. Wessely provides a film-reading service for chiropractors and lectures to both chiropractic undergraduates and postgraduates in Europe. She can be reached at: mwessely@ifec.net; michelle_wessely@yahoo.com; (0033) (0)1 45 15 89 10.

References
1. Yochum T, Rowe L. Arthritic Disorders. Essentials of Skeletal Radiology. 2nd ed. Baltimore: Williams and Wilkins; 1996: 795–974.
2. Berquist,TH. Musculoskeletal Imaging Companion. Arthropathies/Connective Tissue Diseases. Philadelphia: Lippincott, Williams and Wilkins; 2002:666–668.
3. Olofsson Y, Book C, Jacobsson LT. Shoulder joint involvement in patients with newly diagnosed rheumatoid arthritis: prevalence and associations. Scandanavian Journal of Rheumatology. 2003;32(1): 25–32.
4. Krolak C, Wirth S, Hoepfner S, Treitl M, Becker-Gaab C, Reiser M. Systematic characterization of sonomorphological changes in the early stage of rheumatoid arthritis. Ultraschall Med. 2003;24(2):101–106.
5. Boutry N, Larde A, Lapegue F, Solau-Gervais E, Flipo RM, Cotten A. Magnetic resonance imaging appearance of the hands and feet in patients with early rheumatoid arthritis. Journal of Rheumatology. 2003;30(4):671–679.