Deep muscle pain, tender points and recovery in acute whiplash patients: A 1-year follow-up study
From: Pain. 2008 Sep 1; [Epub ahead of print]
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 whiplash associated disorders grade 2 (n=153) or grade 3 (n=4) seen about 5 days after injury and who subsequently had or had not recovered 1 year after a neck 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 whiplash associated disorder 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, 107 and 384 days 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 and trapezius muscles 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.
