Comparison of vibration perception thresholds in individuals with diffuse upper limb pain and carpal tunnel syndrome

Abstract

The study objective was to compare vibration perception and patterns of blood flow in outpatients with diffuse upper limb pain disorder (ULPD), carpal tunnel syndrome (CTS) and age and sex matched healthy controls. Vibration perception and discrimination thresholds were compared in subjects with ULPD (n=27), CTS (n=27) and healthy matched controls (n=54). Vibration measurements were taken bilaterally at three sites: (a) over the dorsum of the second and (b) fifth metacarpals and (c) the palmar aspect of the first and second metacarpals, corresponding to the innervation territories of the radial, ulnar and median nerves, respectively. Non-invasive assessments of peripheral blood flow were also performed in both limbs. When compared to healthy controls, subjects with ULPD had widespread elevation of vibration thresholds both ipsilateral and contralateral to the symptomatic limb. Subjects with CTS had similarly elevated vibration thresholds at sites both adjacent to and distant from the site of peripheral nerve injury. The responses to cold pressor testing of the upper limbs were physiologically normal in both the CTS and ULPD patient groups. Furthermore, there were no significant differences in the haemodynamic responses between the patient groups. The global elevation of vibration thresholds in subjects with both ULPD and CTS is consistent with altered central nervous system mechanisms, common to both conditions, which may be either adaptive to or maintaining the perception of pain.

Reply to the letter to the editor by Tamburin and Zanette

“…Unlike stated in their letter (Tamburin and Zanette, 2011), we did observe altered vibration and cold detection thresholds over the median innervation territory of the hand. This impairment is in agreement with earlier reports by both Tucker et al (2007) and Tamburin et al (2010). The testing location of the shaft of the first metacarpal was specifically chosen to compare the results of our study with QST data that were available at the time the study was designed (Tucker et al, 2007;de la Llave-Rincon et al, 2009).…”

Specific Mechanical Pain Hypersensitivity Over Peripheral Nerve Trunks in Women With Either Unilateral Epicondylalgia or Carpal Tunnel Syndrome

“…70 Several studies have demonstrated that LE is characterized by bilateral sensory 21,22,53 and motor 6,54 changes, suggesting central sensitization mechanisms. Furthermore, vibration, 63 thermal, 19 and motor 29 impairments have been identified bilaterally in patients with unilateral CTS, which also suggests the presence of central mechanisms. A recent study demonstrated that LE is different to CTS in some sensory disturbances, as no deficit in thermal and vibration detection thresholds were found in individuals with LE.…”

Thermal and vibratory thresholds after liposuction in patients with Dercum's disease

“…In subjects with other disorders, for example diffuse upper limb pain disorders [17], chronic whiplash [18] and different unilateral muscoskeletal disorders that encompass diffuse pain, such as frozen shoulder and epicondylitis [19], previous studies have shown decreased pain thresholds but raised detection of vibration and thermal thresholds both ipsilaterally and contralaterally to the affected limb. Such findings have suggested a common generalised disturbance of somatosensory processing and changed central nervous perception, rather than peripheral nerve dysfunction in patients with such chronic pain syndromes [17,20].…”

“…Such findings have suggested a common generalised disturbance of somatosensory processing and changed central nervous perception, rather than peripheral nerve dysfunction in patients with such chronic pain syndromes [17,20]. In contrast to this, it has been shown that patients with fibromyalgia have hypersensitivity to pain, but normal perception thresholds [21,22], which indicates that different mechanisms are involved in the various pain syndromes.…”