An image-based method to measure joint deformity in inflammatory arthritis: development and pilot study

Area of Science:

• Rheumatology
• Medical Imaging
• Orthopedics

Background:

• Quantifying joint deformity in rheumatoid arthritis (RA) and psoriatic arthritis (PsA) is difficult.
• Existing methods may not fully capture the extent of bone erosion and periosteal changes.
• Accurate measurement is crucial for disease monitoring and treatment evaluation.

Purpose of the Study:

• To introduce and validate a novel surface-based method for quantifying joint bone erosions and abnormal periosteal growths.
• To assess the accuracy and sensitivity of this new method in measuring bone changes.
• To compare bone erosion levels between patients with RA/PsA and healthy individuals.

Main Methods:

• Developed a method measuring the difference between predicted healthy and actual diseased joint surfaces.
• Optimized the method using artificial bone erosions and growths for calibration.
• Measured 46 healthy and diseased patient joint surfaces, analyzing bone erosion and periosteal changes.

Main Results:

• The method achieved average sensitivity errors of ≤0.27 mm when measuring artificial bone erosions and growths.
• Patients with RA and PsA demonstrated significantly more bone erosion compared to healthy subjects.
• The surface-based approach proved effective in detecting and quantifying bone alterations.

Conclusions:

• The novel surface-based method provides accurate quantification of bone erosions and periosteal growths in arthritic joints.
• This technique offers a reliable way to interpret and measure bone changes associated with psoriatic arthritis and rheumatoid arthritis.
• Surface-based outcomes represent a new paradigm for assessing joint structural damage in inflammatory arthritis.