The injury impairment scale in pelvic and lower limb fractures sustained in road traffic accidents.

To assess the validity of the Injury Impairment Scale for pelvic and lower limb fractures sustained in road traffic accidents, the Expected Injury Impairment Scale score was correlated with the Observed Injury Impairment Scale score for patients who attended the Accident and Emergency department in Nottingham during 1992 and 1993. Seventy-four per cent of the patients had an Observed IIS score equivalent to their Expected IIS score. The validity of the observed IIS scores for mobility and pain were assessed by correlating them with: (a) Functional assessment and visual pain scale scoring systems. A significant difference was found between scores 0 and 1 for both mobility and pain and between scores 1 and 2 for mobility only. (b) The physical functioning and pain parts of the Short Form 36 (SF36) disability questionnaire. A significant difference was found between scores 0 and 1 for both mobility and pain and between scores 1 and 2 for mobility only. The level of impairment was compared with the level of disability for mobility using the functional assessment score and the physical functioning part of the SF36 and for pain using the visual pain scale score and the pain part of the SF36 and no statistically significant relation was found. This study does not validate the IIS for pelvic and lower limb fractures. However, minor modifications would make it a valid and useful method for predicting the outcome of these injuries.