Feasibility, precision and validity of a novel fully automated quantitative method developed for measurement of digital joint space width in inflammatory arthritis

• ObjectivesIn rheumatoid arthritis (RA) radiographic joint damage is a key long-term outcome and is often evaluated in clinical trials through the van der Heijde modified Sharp method which includes the joint space narrowing (JSN) score. The aim of this study was to investigate the feasibility, the precision and the validity of a novel fully automated method for quantifying joint space width (JSW) in metacarpophalangeal (MCP) and proximal interphalangeal (PIP) joints in order to develop a method for use in the clinic where manual scoring is usually not available.MethodsRadiographs from the SWEFOT trial were examined and processed for automated quantification of 1 year change (1yCh) in average JSW in MCP joints 2, 3 and 4 and proximal PIP joints 2 and 3. The relationship between change in JSW and change in JSN was studied using linear regression.Results1yCh in MCP234 and PIP23 was successfully measured in 119/119 and 117/119 patients respectively. Reproducibility expressed as coefficient of variation was 1.4% for MCP234 JSW and 1.6% for PIP23 JSW. There was a significant relationship between 1yCh in MCP234 JSW and 1yCh in JSN (r= -0.19, p=0.036). In contrast, 1yCh in PIP23 JSW was not independently significantly associated with 1yCh in JSN.Conclusion Automated measurement of change in MCP234 JSW was technically feasible and it was related to the change in JSN. Adding PIP23 JSW did not strengthen the association to JSN. We are continuing to study the possible utility of JSW in clinical trials and clinical practice.

Subject headings

TEKNIK OCH TEKNOLOGIER  -- Medicinteknik -- Medicinsk bildbehandling (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Medical Engineering -- Medical Image Processing (hsv//eng)

MEDICIN OCH HÄLSOVETENSKAP  -- Klinisk medicin -- Radiologi och bildbehandling (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Clinical Medicine -- Radiology, Nuclear Medicine and Medical Imaging (hsv//eng)

Keyword

Joint space width

rheumatoid arthritis

Computer-aided joint space analysis

Sharp van der Heijde score

Digital X-ray radiogrammetry

Publication and Content Type

vet (subject category)

ovr (subject category)