title: 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.
authors.affiliation: The Ernest Cooke Vascular and Microvascular Unit, St. Bartholomews Hospital, London EC1A 7BE, UK Department of Psychological Medicine, St. Bartholomews Hospital, London EC1A 7BE, UK William Harvey Institute, Barts and The London, Queen Mary School of Medicine & Dentistry, London E1 2AD, UK Clinical Pharmacology, Barts and The London, Queen Mary School of Medicine and Dentistry, London E1 2AD, UK Harold Wood Hospital, Romford RM3 0BE, UK Pain Centre, Department of Neurosurgery, Karolinska University Hospital/Karolinska Institute, Stockholm, Sweden.
authors.forename: A T
authors.initials: AT
authors.lastname: Tucker
authors.forename: P D
authors.initials: PD
authors.lastname: White
authors.forename: E
authors.initials: E
authors.lastname: Kosek
authors.forename: R M
authors.initials: RM
authors.lastname: Pearson
authors.forename: M
authors.initials: M
authors.lastname: Henderson
authors.forename: A R
authors.initials: AR
authors.lastname: Coldrick
authors.forename: E D
authors.initials: ED
authors.lastname: Cooke
authors.forename: B L
authors.initials: BL
authors.lastname: Kidd
mesh_terms: D000222:Adaptation, Physiological; D000293:Adolescent; D000328:Adult; D000368:Aged; D002349:Carpal Tunnel Syndrome / Q000503:physiopathology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010146:Pain / Q000503:physiopathology*; D010812:Physical Stimulation / Q000379:methods*; D012684:Sensory Thresholds; D034941:Upper Extremity / Q000503:physiopathology*; D014732:Vibration