Inflammation as the Possible Cause of Cystic Radiolucencies in Carpal Bones of Patients on Hemodialysis

In this investigation of the etiology of amyloid-associated arthropathy in hemodialysis (HD) patients, determination of whether amyloid deposition triggered the formation of the cystic radiolucent bone lesions was attempted. The relationship between these lesions in carpal bones and carpal tunnel syndrome (CTS) was studied by radiography and tomography, and one of the carpal bones, the os capitatum, was examined histologically at autopsy. The mean number of cystic radiolucent lesions in carpal bones of the 21 patients with CTS was significantly greater than that in the 43 patients without CTS. On tomograms, cystic radiolucent lesions of carpal bones had interconnections with joint spaces. Inflammatory fibrous granulation tissue, with or without amyloid deposits, was found in the cystic lesions. It was concluded that cystic radiolucent lesions in carpal bones of patients on HD was related to CTS, and that synovitis and subsequent chronic inflammation were responsible. Thus, amyloid deposits did not trigger the formation of such lesions.