Osteoarthritis of the scaphoidtrapezium joint: an early sign of calcium pyrophosphate dihydrate disease

The aim of this study was to determine the value of scaphoidtrapezium osteo arthritis (ST osteoarthritis) as an early sign of calcium pyrophosphate dih ydrate disease (CPDD) in a cohort of patients undergoing surgery for osteoa rthritis of the first carpometacarpal joint. We examined whether patients w ith cartilage calcification of the wrist at the time of operation had ST os teoarthritis, indicating CPDD at an earlier time (retrospective study), and whether patients with ST osteoarthritis but without cartilage calcificatio n at the time of surgery develop radiological or clinical signs of CPDD at a later time (prospective study). From 1 January 1989 to 31 December 1995 a total of 169 patients (from an orthopaedic clinic) with a diagnosis of ost eoarthritis of the first carpometacarpal joint were included in the study; 167 underwent surgery and two were treated without. Of the 16 patients show ing calcification on surgery and therefore included in the retrospective st udy, 12 had prior radiographs, of which eight showed ST osteoarthritis. Amo ng these, four had no concomitant cartilage calcification in the prior radi ographs. Of the 32 patients in the prospective group having ST osteoarthrit is but no calcifications at the time of surgery, 27 could be clinically exa mined. Of these, two showed cartilage calcifications on the followup radiog raphs of the hands. The presence of ST osteoarthritis is a helpful diagnost ic finding for the diagnosis of CPDD, especially in cases without radiograp hic cartilage or fibrocartilage calcification of the wrist. ST osteoarthrit is may then point to the correct diagnosis.