Seeing through the ′MIST′ (Minor Impact Soft Tissue Injury)?

Chedoke Rehabilitation Centre, Hamilton, Ontario Correspondence: Dr E Tunks, Chedoke Rehabilitation Centre, PO Box 2000, Hamilton, Ontario L8N 3Z5. Telephone 905-521-2100 ext 77038, fax 905-521-7954, e-mail tunks@hhsc.ca I n this issue, Centeno et al (pages 71-74) discuss the merits of the concept of ‘minor impact soft tissue injury’ (MIST), or chronic pain after whiplash-associated disorder. We like to think of ourselves as reasonable clinicians and that clinical beliefs that are long-held and with apparent face validity do not need more proof. Yet, often we find that when venerable opinions are put to the test in clinical trials, some are refuted. With regard to ‘whiplash-associated disorder’, one might assume that once we have excluded fracture and neural injury, we are left with soft tissue (muscular and ligamentous) sprain/strain as the only remaining mechanism of injury. By analogy to sprains and strains elsewhere in the body, we might reasonably assume that the healing curve for this soft tissue follows a time-limited trajectory of inflammation and healing, that pain might be expected during that healing process (from two weeks to two months at the outside) and, that, by the end of that time, no impairment or disability should remain from the whiplash injury. Centeno et al examined two main hypotheses inherent in the ‘sprain/strain’ view of whiplash: