Proximal pain in patients with carpal tunnel syndrome: a clinical-neurophysiological study

Patients with carpal tunnel syndrome (CTS) usually complain of pain and paresthesia in the hand or wrist, but pain proximally to the wrist has been frequently reported in this condition. This study was aimed at understanding which clinical features are associated with the presence of proximal pain (PP) in the upper limb of CTS patients. We recruited 250 patients with clinical and neurophysiological evidence of CTS. After thorough selection to rule out concomitant upper limb painful conditions, 112 patients (175 hands) were included. PP was defined as the presence of pain in the upper limb proximally to the wrist (neck excluded) in association with sensory complaints in the hand. Patients were asked about the presence and severity of proximal sensory complaints, the distribution of sensory complaints in the hand, and underwent an objective evaluation and neurographic study. Thenar muscle strength was significantly larger, the neurophysiological measures were significantly less severe, and hand paresthesia was significantly greater in patients with PP. The neurographic score and the measures of median nerve damage were inversely correlated with the severity of PP. PP was related to extramedian spread of symptoms in the hand. None of the objective/neurographic variables was related to severity of sensory complaints restricted to the hand. PP may be found in a consistent number of CTS patients. PP may represent a clinical marker of mild median nerve damage. The presence of proximal complaints might be related to peripheral or central nervous system mechanisms.