EAD INJURY IS ONE OF THE most common injuries in the Western world with an estimated incidence of hospitaltreated patients with minor head injury of 100 to 300 per 100 000 population. 1 Minor head injury is commonly defined as blunt trauma to the head, after which the patient has lost consciousness for less than 15 minutes or has a short posttraumatic amnesia of less than 1 hour, or both, as well as a normal or minimally altered mental status on presentation (a Glasgow Coma Scale [GCS] score of 13-15). 2,3 Intracranial complications of minor head injury are infrequent (6%-21%) but potentially life-threatening and may require neurosurgical intervention in a minority of cases (0.4%-1.0%). 3-8 Neurocranial injury that does not require See also pp 1511 and 1551 and Patient Page.

The authors propose the highly sensitive CHIP prediction rule for the selective use of CT in patients with minor head injury with or without loss of consciousness.

radiology.rsnajnls.org/cgi/content/full/2452061509/DC1 (c) RSNA, 2007.

Objective: A history of loss of consciousness (LOC) or post-traumatic amnesia (PTA) is commonly considered a prerequisite for minor head injury (MHI), although neurocranial complications also occur when LOC/PTA are absent, particularly in the presence of other risk factors. The purpose of this study was to evaluate whether known risk factors for complications after MHI in the absence of LOC/PTA have the same predictive value as when LOC/PTA are present. Methods: A prospective multicentre study was performed in four university hospitals between February 2002 and August 2004 of consecutive blunt head injury patients (>16 years) presenting with a normal level of consciousness and a risk factor. Outcome measures were any neurocranial traumatic CT finding and neurosurgical intervention. Common odds ratios (OR) were estimated for each of the risk factors and tested for homogeneity. Results: 2462 patients were included: 1708 with and 754 without LOC/PTA. Neurocranial traumatic findings on CT were present in 7.5% and were more common when LOC/PTA was present (8.7%). Neurosurgical intervention was required in 0.4%, irrespective of the presence of LOC/PTA. ORs were comparable across the two subgroups (p.0.05), except for clinical evidence of a skull fracture, with high ORs both when LOC/PTA was present (OR = 37, 95% CI 17 to 80) or absent (OR = 6.9, 95% CI 1.8 to 27). LOC and PTA had significant ORs of 1.9 (95% CI 1.0 to 2.7) and 1.7 (95% CI 1.3 to 2.3), respectively. Conclusion: Known risk factors have comparable ORs in MHI patients with or without LOC or PTA. MHI patients without LOC or PTA need to be explicitly considered in clinical guidelines.H ead injury is one of the most common injuries seen in emergency departments, minor head injury (MHI) accounting for 90-95% of cases.