What Parts of the Body Are Affected by PsA?
Psoriatic arthritis can affect any part of the body where there are joints or a joint and connective tissues. The connective tissues and synovial fluids that are found in the joint areas are highly susceptible to the inflammatory processes that happen as a result of PsA. Additionally, the chronic inflammation that is a hallmark of PsA can affect the other parts of the body that are not the joints–the vascular system, eyes, ears, and skin.
Hands and wrists
Symptoms of PsA in the hands and wrists include stiffness, especially first thing in the morning or after a period of rest. The initial symptoms of psoriatic arthritis in the hands and wrists may be swelling, warmth, and stiffness. Joint pain and reduced range of motion are also common symptoms in the hands and wrists. The fingers and nails may also be affected by PsA.
One or both hands or wrists may be affected in a patient with psoriatic arthritis. PsA is frequently asymmetrical, affecting only one side of the body. For example, PsA may involve the right hand or wrist while the left hand is unaffected. PsA can also be symmetrical, affecting both sides of the body, such as both hands and/or wrists at the same time.
Fingers and toes
Psoriatic arthritis often begins in the distal joints, those farthest away from the core of the body, such as the joints in the fingers and toes. The disease can cause significant swelling in the fingers and toes, creating a sausage-like appearance, called dactylitis. Dactylitis is a combination of swelling in the joint, as well as inflammation at the attachment points of ligaments and tendons, a condition called enthesitis. Inflammation of the fingers and toes can erode the joints, and lead to deformity and loss range of motion and function.
Severe damage to fingers and toes results in shortening of the digits, deformity, and loss of function, this is called arthritis mutilans. This is the most severe form of PsA and occurs in approximately 5% of people with PsA.
Fingernails and toenails can also be affected. In fact, nail changes are often an early warning sign that a person with psoriasis is also developing psoriatic arthritis. Nail changes can affect all or part of one or more of the nails, but most commonly occur on the fingernails.
Feet and Heel
The initial symptoms of psoriatic arthritis in the feet are pain, swelling, warmth, and stiffness. Psoriatic inflammation may affect the entheses in the foot and heel. When the inflammation of this connective tissue occurs, it often appears at the heel as Achilles tendonitis or at the bottom of the foot as plantar fasciitis. Plantar fasciitis is characterized by pain that feels like the arch of the foot is tearing, and the pain is often worse in the morning or after a period of inactivity. The pain a person experiences with Achilles tendon affects the tendon which runs from the heel up to the calf.
Legs and knees
Symptoms of PsA in the legs and knees include stiffness, especially first thing in the morning or after a period of rest, joint pain, swelling, and reduced range of motion.
One or both knees may be affected in a patient with psoriatic arthritis. PsA is frequently asymmetrical, affecting only one side of the body. For example, PsA may involve the right knee while the left knee is unaffected. PsA can also be symmetrical, affecting both sides of the body, such as both legs at the same time.
The spine can be involved in about 40 percent of people with PsA, but it is rare for the spine to be the only area involved in psoriatic arthritis. While the lower back is usually the part of the spine that experiences the most inflammation, and where a person with PsA is most likely to experience back pain, neck pain is often experienced as well.
Both back and neck pain will usually feel better with activity and worse with rest. Inflammatory back pain can frequently awaken those who suffer from this symptom from sleep at night.
The hips are not frequently affected in most people with PsA. It is estimated that the hips become inflamed due to PsA in less than 10% of cases. People who have the onset of PsA symptoms before age 30 seem to be at the greatest risk for hip involvement, especially if they have spinal involvement. Pain in the hip joint may radiate outward and also include pain in the groin, outer thigh, or buttocks. Inflammation affecting the hips may cause stiffness, and affect the range of motion, making it difficult to walk without a limp.