Epidemiologic associations of carpal tunnel syndrome and sleep position: Is there a case for causation?
INTRODUCTION: Carpal tunnel syndrome (CTS) is thought to be due to compression of the median nerve in the carpal tunnel. It is known that carpal tunnel pressures are elevated in wrist postures of flexion and extension and in those patients with CTS. Classic symptoms of CTS include night waking with pain, tingling, and numbness. These classic symptoms stimulated our interest in the relationship of sleep to the development of CTS. METHOD: We reviewed the literature surrounding the epidemiology of CTS and the literature regarding sleep disturbances. Through careful distillation of these studies and a process of reasoning, we have developed a hypothesis for a causal mechanism of CTS. RESULTS: Epidemiologically, it has been shown that CTS is associated with age, gender, increased body mass index (BMI), diabetes, pregnancy, and is more common in some populations. The same associations noted above for CTS are strongly associated with sleep disturbances. Sleep disturbances due to age, gender,
