INTRODUCTION: Carpal tunnel syndrome (CTS) is considered a simple entrapment of 
the median nerve at the carpal tunnel. In the last years, several studies have 
demonstrated the presence of peripheral and central sensitization mechanisms.
AIM: To review the basis neurophysiology of peripheral and central sensitization 
by applying them to CTS and to determine their clinical repercussions.
DEVELOPMENT: Several studies have revealed that patients with CTS exhibit 
somato-sensory changes in areas innervated by the median nerve and also in areas 
non-related with the median nerve. Individuals with CTS exhibited widespread 
mechanical and thermal pain hyperalgesia, although they suffered from unilateral 
symptoms. Further, patients also showed wide-spread impairments in vibration 
conduction, deficits in fine motor control and changes in the somato-sensory 
cortex. These evidences support the presence of a complex process of peripheral 
and central sensitization in patients with CTS which may constitute a negative 
prognosis factor for the management of these patients.
CONCLUSIONS: The advances in neurosciences in the last years support the 
presence of peripheral and central sensitization mechanisms in CTS. These 
mechanisms justify the necessity of conceptual changes and in the management, 
both conservative and surgical, of this syndrome. Additionally, central 
sensitization can also play a relevant role in the prognosis of CTS since it can 
constitute a negative prognosis factor for its treatment.