Carpal collapse in patients with rheumatoid arthritis

The inflammation of the wrist and carpal collapse play an important role in the deformity of the rheumatoid hand and leads to functional limitation. The aim of this study was to evaluate carpal collapse and related clinical variables in patients with rheumatoid arthritis (RA). Carpal height ratio (CHR) indicating the degree of carpal collapse was measured in 33 female RA patients with a mean age of 41.9+/-10.3 years and 30 female healthy control subjects with a mean age of 40.5+/-9.2 years. The normal range of the carpal collapse was defined in our study population and the incidence of carpal collapse was determined. The correlation between carpal collapse and clinical and laboratory variables including pain by visual analog scale, Ritchie articular index, erythrocyte sedimentation rate, C-reactive protein, health assessment questionnaire indicating functional status, and Larsen roentgenological evaluation were determined. Subgroup analyses were also performed in patients with and without carpal collapse. The mean disease duration of the patients was 12.4+/-5.5 years. The mean CHR index of the patients was significantly lower than in the control group (0.47+/-4.3 and 0.54+/-1.4 respectively). CHR <0.48 was defined as carpal collapse in our study group. Seventeen patients (51.5%) had carpal collapse in the patient group. None of the clinical or laboratory variables except levels of disease duration and Larsen score was correlated with carpal collapse as represented by CHR. The best related clinical variable with carpal collapse was found as duration of disease. The mean duration of disease and the Larsen score were significantly higher in patients with carpal collapse than those without collapse. Other clinical parameters and functional status were similar between patients with and without carpal collapse. In conclusion, although various clinical parameters and functional disability in patients with RA may not be correlated with radiological malalignment, the carpal collapse may be more common in RA than is generally recognized.