Incidence of Complex Regional Pain Syndrome Following the Carpal Tunnel Release Surgery

[Background]Complex regional pain syndrome (CRPS) is a chronic syndrome of pain usually caused by an initiating noxious event in the periphery. Carpal tunnel release (CTR) surgery has been known to associate with the development of CRPS.[Objectives]The incidence rate of CRPS has been attributed to the differences in ethnic and socioeconomic background of the cohort. Here, we aimed at evaluating the incidence of CRPS after CTR surgery in Iranian population for the first time.[Methods]In a prospective study, a total of 106 patients with carpal tunnel syndrome (CTS), who underwent CTR surgery, were included in this cohort. The patients’ medical records were evaluated and the incidence of CRPS after CTR surgery was assessed accordingly. Visual analogue scale (VAS) was used to subjectively evaluate the pain level in each CRPS patient.[Results]In this study, 7 (6.6%) cases of postoperative CRPS including 1 (14.2%) male and 6 (85.8%) females were identified at a mean follow-up period of 6.1 ± 2.4 months, ranging from 2 to 7 months. The mean age of CRPS cases was 49.5 ± 10.6, ranging from 31 to 74 years. In 2 patients the dominant hand and in 5 patients nondominant hand were involved. The mean preoperative VAS was 2.9, ranging from 2 to 4, which increased to 8.1 in CRPS patients, ranging from 7 to 9.[Conclusions]CRPS could be seen frequently following the CTR surgery, giving rise to a pain level of significantly higher than the initial pain level. Consequently, the patients should be informed of this potential adverse consequence of CTR surgery, especially those having the risk factors of this condition including gender, age, and hand dominancy.