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Calcium pyrophosphate dihydrate crystal deposition disease of the wrist: trapezioscaphoid joint abnormality.

OBJECTIVE
To determine whether trapezioscaphoid (TS) joint alterations are associated with calcium pyrophosphate dihydrate (CPPD) crystal deposition disease and, if so, to determine the nature of these alterations.


METHODS
Radiographs of 160 wrists with evidence of chondrocalcinosis were evaluated with regard to TS joint abnormalities, and findings were compared with a similar number of radiographs in an age and sex matched control population in whom no evidence of chondrocalcinosis or other calcification in the wrist was seen. Two radiologists in consensus recorded radiographic findings in both groups, and a third radiologist blinded to the presence or absence of chondrocalcinosis reviewed wrist radiographs in both groups in a random order. Correlation of TS joint abnormalities with other changes in the wrist was also accomplished. RESULTS; TS arthropathy was found in 43.7% of CPPD wrists and in 14.4% of control wrists in the consensus evaluation. In the blind evaluation, 30% of CPPD wrists and 12.5% of control wrists had TS arthropathy. The degree of arthropathy was more extensive in the CPPD group than in the control group. Features associated with TS arthropathy in the patient population were first carpometacarpal arthropathy and subchondral cysts in the scaphoid or trapezium, or both bones.


CONCLUSION
CPPD patients, compared to a control population, reveal frequent and significant radiographic abnormalities of the TS joint that may be suggestive of the diagnosis, even in patients in whom chondrocalcinosis is obscured or absent. The features associated with TS arthropathy are first carpometacarpal arthropathy and subchondral cysts in the scaphoid and trapezium.