Central sensitization does not identify patients with carpal tunnel syndrome who are likely to achieve short-term success with physical therapy

Abstract

The aim of the current study was to identify whether hyperexcitability of the central nervous system is a prognostic factor for individuals with carpal tunnel syndrome (CTS) likely to experience rapid and clinical self-reported improvement following a physical therapy program including soft tissue mobilization and nerve slider neurodynamic interventions. Women presenting with clinical and electrophysiological findings of CTS were involved in a prospective single-arm trial. Participants underwent a standardized examination and then a physical therapy session. The physical therapy sessions included both soft tissue mobilization directed at the anatomical sites of potential median nerve entrapment and a passive nerve slider neurodynamic technique targeted to the median nerve. Pressure pain thresholds (PPT) over the median, radial and ulnar nerves, C5-C6 zygapophyseal joint, carpal tunnel and tibialis anterior muscle were assessed bilaterally. Additionally, thermal detection and pain thresholds were measured over the carpal tunnel and thenar eminence bilaterally to evaluate central nervous system excitability. Subjects were classified as responders (having achieved a successful outcome) or non-responders based on self-perceived recovery. Variables were entered into a stepwise logistic regression model to determine the most accurate variables for determining prognosis. Data from 72 women were included in the analysis, of which 35 experienced a successful outcome (48.6%). Three variables including PPT over the C5-C6 joint affected side <137 kPa, HPT carpal tunnel affected side <39.6º and general health >66 points were identified. If 2 out of 3 variables were present (LR + 14.8), the likelihood of success increased from 48.6 to 93.3%. We identified 3 factors that may be associated with a rapid clinical response to both soft tissue mobilization and nerve slider neurodynamic techniques targeted to the median nerve in women presenting with CTS. Our results support that widespread central sensitization may not be present in women with CTS who are likely to achieve a successful outcome with physical therapy. Future studies are now necessary to validate these findings.

Clinical reasoning for manual therapy management of tension type and cervicogenic headache

“…37 In contrast, Ferná ndez-de-las-Peñas et al reported that the presence of peripheral sensitization, instead of widespread central sensitization, was related to a positive physical therapy response in women with carpal tunnel syndrome. 38 Current data support the role of central sensitization in headaches, particularly tension type headache. However, since central sensitization is generated by prolonged nociceptive inputs from peripheral structures 39 and dynamically influenced by activity and location of these nociceptive inputs, 40 the role of peripheral mechanisms should be not ignored.…”

Clinical, Physical, and Neurophysiological Impairments Associated With Decreased Function in Women With Carpal Tunnel Syndrome

“…These findings are consistent with those of a previous study that examined the predictive validity of PPT in identifying individuals with CTS who were likely to have a favorable prognosis. 17 The positive predictor of outcome in that previous study was PPT over the C5-6 joint, with a positive likelihood ratio of 4.2. 17 This may be related to the association between upper extremity function and the cervical spine.…”

“…17 The positive predictor of outcome in that previous study was PPT over the C5-6 joint, with a positive likelihood ratio of 4.2. 17 This may be related to the association between upper extremity function and the cervical spine. Sterling 44 also demonstrated that higher pressure and cold hypersensitivity were associated with poor outcomes in subjects with whiplash-associated disorders.…”

“…The assessed locations have been reported to exhibit mechanical pain hypersensitivity as a sign of central sensitization in individuals with CTS. 12,17,18 The mean of 3 trials was calculated and used for the analysis. A 30-second rest was allowed between each measure.…”

Whiplash associated disorders: A prospective investigation of the effects of cervical medial branch radiofrequency neurotomy on sensory, motor and psychological Features

“…Some of the sensory, motor and psychological measures may influence responsiveness to these procedures. For example, central sensitization has been demonstrated to be a predictor of poor prognosis in individuals with musculoskeletal pain undergoing conservative treatment [186,349] and individuals undergoing surgery [350]; whilst catastrophization predicts poor response to painful procedures [245,351] and increased pain and disability ratings post surgery [352]. The presence of posttraumatic stress symptoms has also been demonstrated to result in more frequent pain and poorer prognosis in headache patients [240].…”