Previous studies have suggested a high prevalence of carpal tunnel syndrome in patients seeking treatment for basal joint arthritis of the thumb. The purpose of this study was to compare the prevalence of carpal tunnel syndrome between individuals with and those without radiographic evidence of basal joint arthritis of the thumb in the general elderly Korean population, and to determine if there is a correlation between the severity of carpal tunnel syndrome shown by electrophysiological studies and the severity of basal joint arthritis as seen on radiographs.
We evaluated hand radiographs and nerve conduction studies of 192 men and 176 women (more than sixty-five years of age) who participated in the Korean Longitudinal Study on Health and Aging. The basal joint of the thumb was assigned a grade for osteoarthritis of 0 to 4 on radiographs with use of the Kellgren and Lawrence criteria. The diagnosis of carpal tunnel syndrome was based on the combination of a positive response to survey questions and a positive nerve conduction study. Motor distal latency and motor conduction velocity were measured to assess the electrophysiological severity of carpal tunnel syndrome.
The prevalence of carpal tunnel syndrome was 16.7% in the group with basal joint arthritis and 10.9% in the group without basal joint arthritis, a difference that was not significant (p = 0.249). Neither motor distal latency nor motor conduction velocity was significantly correlated with the severity of the basal joint arthritis in the entire group of 368 study subjects (p = 0.154 and p = 0.662, respectively) or in those with carpal tunnel syndrome (p = 0.603 and p = 0.998, respectively).
This study of Koreans who were more than sixty-five years of age showed that the prevalence of carpal tunnel syndrome is similar in patients with and those without radiographic findings of basal joint arthritis of the thumb. We found no correlation between the electrophysiological severity of carpal tunnel syndrome and the severity of basal joint arthritis.