Determining the origin of pain is crucial when evaluating patients with multiple joint pain. A thorough physical examination is the first and most important step to distinguish whether the pain arises from the joints themselves, surrounding structures like tendons, muscles, and bursae, or a combination of both. This initial assessment guides further diagnostic steps and treatment strategies.
Differentiating Joint Pain Origins
Pinpointing the exact location of tenderness and swelling provides valuable clues. Pain or swelling localized to one side of a joint or away from the joint line often indicates an extra-articular source, such as tendinitis or bursitis. Conversely, tenderness directly along the joint line or a more widespread involvement within the joint suggests an intra-articular cause.
A simple yet effective test involves compressing the joint without bending or straightening it. This maneuver typically elicits minimal pain in conditions like tendinitis or bursitis. However, in cases of arthritis, this compression will be significantly painful. Furthermore, observing the impact of active and passive joint motion is informative. Pain that intensifies with active movement but not with passive movement may point towards tendinitis or bursitis, indicating an issue outside the joint. In contrast, intra-articular inflammation usually restricts both active and passive range of motion considerably.
Alt text: Table listing suggestive findings in polyarticular joint pain, categorized by general and hand findings, and associated possible causes including rheumatoid arthritis, psoriatic arthritis, gout, reactive arthritis, and systemic lupus erythematosus.
Assessing Joint Inflammation
Another critical aspect of the evaluation is to determine if the joints are inflamed. Pain experienced during rest and upon initiating movement is a strong indicator of joint inflammation. Conversely, pain that worsens with activity and improves with rest is more characteristic of mechanical or non-inflammatory conditions, such as osteoarthritis. While increased warmth and redness (erythema) are classic signs of inflammation, their absence doesn’t rule it out, as these findings can be subtle or insensitive.
Systemic Inflammatory Disorder Indicators
Certain clinical findings suggest a systemic inflammatory disorder affecting the joints. Prolonged morning stiffness, stiffness following periods of inactivity (known as the gel phenomenon), joint swelling without a history of trauma, and systemic symptoms like fever or unintentional weight loss are all red flags. If the pain is diffuse, vaguely described, and primarily affects myofascial structures without overt signs of inflammation, fibromyalgia should be considered.
Patterns of Joint Involvement
The pattern of joints affected provides further diagnostic direction. Symmetrical joint involvement, affecting the same joints on both sides of the body, is commonly seen in rheumatoid arthritis. In contrast, asymmetrical involvement is more typical of psoriatic arthritis, gout, reactive arthritis, and enteropathic arthritis.
Examination of the hand joints can yield additional differentiating clues, helping to distinguish osteoarthritis from rheumatoid arthritis and suggesting other potential diagnoses. For example, characteristic findings like Heberden’s nodes and Bouchard’s nodes can point towards osteoarthritis, while swan-neck or boutonnière deformities are more indicative of rheumatoid arthritis.
Alt text: Table comparing differential features of the hand in rheumatoid arthritis and osteoarthritis, focusing on joint swelling, bony hypertrophy, DIP, MCP, PIP, and wrist involvement, aiding in diagnosis of multiple joint pain.
Spinal Pain and Peripheral Arthritis
The presence of spinal pain alongside peripheral arthritis raises suspicion for a seronegative spondyloarthropathy. This group includes conditions like ankylosing spondylitis, reactive arthritis, psoriatic arthritis, and enteropathic arthritis. While spinal pain can also occur in rheumatoid arthritis, it’s less common and typically involves the cervical spine. New-onset oligoarthritis (pain in few joints) combined with spinal pain is particularly suggestive of a seronegative spondyloarthropathy, especially if there’s a family history of such disorders. Specific symptoms like eye redness and pain along with low back pain are indicative of ankylosing spondylitis. A history of plaque psoriasis in a patient developing new-onset oligoarthritis strongly suggests psoriatic arthritis.
By systematically evaluating the location, characteristics, and pattern of joint pain, along with associated clinical findings, clinicians can effectively narrow down the differential diagnosis of multiple joint pain and guide appropriate management.
