title: Deep muscle pain, tender points and recovery in acute whiplash patients: a 1-year follow-up study.
abstract: Local sensitization to noxious stimuli has been previously described in acute whiplash injury and has been suggested to be a risk factor for chronic sequelae following acute whiplash injury. In this study, we prospectively examined the development of tender points and mechano-sensitivity in 157 acute whiplash injured patients, who fulfilled criteria for WAD grade 2 (n=153) or grade 3 (n=4) seen about 5 days after injury (4.8+/-2.3) and who subsequently had or had not recovered 1 year after a cervical sprain. Tender point scores and stimulus-response function for mechanical pressure were determined in injured and non-injured body regions at specific time-points after injury. Thirty-six of 157 WAD grade 2 patients (22.9%) had not recovered, defined as reduced work capacity after 1 year. Non-recovered patients had higher total tender point scores after 12 (p<0.05), 107 (p<0.05) and 384 days (p<0.05) relative to those who recovered. Tenderness was found in the neck region and in remote areas in non-recovered patients. The stimulus-response curves for recovered and non-recovered patients were similar after 12 days and 107 days after the injury, but non-recovered patients had steeper stimulus-response curves for the masseter (p<0.02) and trapezius muscles (p<0.04) after 384 days. This study shows early mechano-sensitization after an acute whiplash injury and the development of further sensitization in patients with long-term disability.
authors.affiliation: Danish Pain Research Center, Department of Neurology, Aarhus University Hospital, Noerrebrogade 44, DK-8000 Aarhus, Denmark Department of Neurophysiology, Aarhus University Hospital, Denmark The Back Research Center, Funen Hospital, University of Southern Denmark, Denmark.
authors.forename: Helge
authors.initials: H
authors.lastname: Kasch
authors.forename: Erisela
authors.initials: E
authors.lastname: Qerama
authors.forename: Alice
authors.initials: A
authors.lastname: Kongsted
authors.forename: Flemming W
authors.initials: FW
authors.lastname: Bach
authors.forename: Tom
authors.initials: T
authors.lastname: Bendix
authors.forename: Troels S
authors.initials: TS
authors.lastname: Jensen