This study assessed the prevalence rates of psychopathology in acute carpal tunnel syndrome (CTS) and acute low back pain (LBP) patients. Psychopathology was assessed with the Structured Clinical Interview for the DSM-III-R (SCID). The results showed that the CTS patients had significantly higher rates of anxiety disorders, both current and lifetime, than the LBP patients. However, LBP patients had significantly higher rates of lifetime substance abuse than the CTS patients. In regard to other types of psychopathology, such as depression, current substance abuse, and somatoform pain disorders, CTS patients had similar rates as the LBP patients. It was concluded that anxiety disorders may be a concomitant of carpal tunnel syndrome, and that treating psychological problems along with physical aspects of the syndrome may increase the patient's chance of a successful therapeutic outcome.