Can patients with low energy whiplash associated disorder develop low back pain?

800 consecutive claimant generated medicolegal reports were analysed for symptomatology of whiplash associated disorder (WAD) including the presence of mid and low back pain. We aimed to establish whether the two were linked and if so if there were correlations between accident vector and severity. We also aimed to establish if a low back injury could result from a vehicular accident in the absence of a neck injury. In addition we examined if occupant bracing and occupant neutral position at the time of the accident affected symptom patterns. We found that a claimed back injury following WAD was independent of both accident severity and accident vectors, approximately 40% claiming injury in low, medium and high violence groups and with rear, frontal and side impact. We established that it was unusual to have a back injury in the absence of a neck injury (18 out of 325, 5.5%) without a past medical history of back pain (72.2% of this group having previous back pain). Occupant bracing was not protective. We also showed that occupant neutral position was not protective against a back injury. We were surprised that patients with next to no car damage had the same incidence of back pain as those involved in more violent crashes when biomechanically unlikely. The complex biopsychosocial response and the relationship to constitutional factors are discussed. The literature concerning forces across the lumbar spine and possibilities of injury is reviewed.