This study was planned to evaluate the effect of psoriatic arthritis on the strength, proprioception, skill, coordination, and functional condition of the hand and to determine the correlate disease activity with these parameters.

Psoriatic arthritis (PsA) is a chronic, progressive, inflammatory arthritis that occurs as a condition associated with patients with psoriasis and may result in permanent joint damage and an increased risk of mortality. Synovial membrane inflammation characterized by increased vascularization and immune cell infiltration is an important feature of psoriatic arthritis. This inflamed synovial microenvironment leads to the formation of synovial pannus, entheseal inflammation, and joint damage. Although PsA is generally thought of as a benign arthropathy, structural damage has been shown with the progression of the disease, along with joint inflammation.As a result of the researches, it has been stated that tissue biomechanical stress and microtraumas that lead to the activation of abnormal natural immune responses in psoriatic arthritis can trigger joint inflammation. In parallel, inflammation is expected to be more common in peripheral joints, which are known to be more exposed to microtrauma. Studies have reported that hand joint involvement is frequently seen in patients with PsA and is an important cause of loss of function and that erosions in hand joints are associated with statistically significant loss of hand strength. Theoretically, either the mechanical effect of the fluid in the acute joint effusion or the components of the inflammatory fluid and the changing capsular compliance after chronic effusion and has been reported that problems may occur in proprioception due to causes such as pain, trauma, and fatigue. However, pain, decreased joint ROM and grip strength, muscle weakness, and hand deformities can affect hand fine hand skills and function. The hypothesis of this study is that supporting the clinical condition of the participants with parameters related to general hand function will be effective in predicting disease progression and disability. Accordingly, the aim of the researchers is to evaluate the effect of PsA on the grip and pinch strength of the hand, proprioception, skill, coordination and functional status, and to determine the relationship of disease activity with these parameters.

Inclusion Criteria:

• Individuals between the ages of 18-65

Exclusion Criteria:

• Neurological diseases that caused sequelae at hand, upper extremity surgeries, neuropathies, traumas, and history of nerve damage
• Psychiatric disorders,
• Reluctance to continue evaluation

Individuals and healthy controls diagnosed with PsA according to the classification criteria for PsA (Classification Criteria for Psoriatic Arthritis, CASPAR).