Purpose: Classification of the lower extremity of the radius does not have prognostic value. We propose a severity score based on the initial radiographic presentation. We tested five radiographic criteria to determine their correlation with the final outcome (function, radiographic aspect, subjective assessment).

Material and methods: The study series included 86 patients (91 wrist fractures) hospitalised between January 1998 and March 2000. The initial radiological severity score (IRSS) was noted on a scale of 20 points (five items): comminution (extent, aspect, localisation), cancellous impaction (metaphyseal, epiphyseal, both), ulnar fractures (localisation), severe fracture deviation, carpal and ligamentary injury. Each item was scored 0 to 4. Higher IRSS indicated a more severe fracture. Initial radiograms with or without traction were analysed carefully. Intra- and inter-observer reliability was proven. To evaluate the prognostic significance of the IRSS, the final outcome was scored using four items: motion (palmar and dorsal flexion, radial and ulnar inclination, pronosupination), final radiogram (frontal and sagittal tilt, index of deviation), subjective outcome (very good, good, fair, poor), osteoarthritis (one or two facets involved). The outcome score was noted on a 20 point scale (higher score indicating poorer outcome).

Results: We found a statistically significant relationship between the IRSS and the final outcome score.

Discussion: Precise analysis demonstrated other significant correlations with the IRSS: skin opening and occupational accident were generally related with poor initial scores. There was no statistically significant relationship with age, gender, high or low-energy trauma, associated upper limb damage, multiple injury, osteoporosis or reflex dystrophy. The final outcome was statistically and logically related with age, osteoporosis, open fractures, but also with reflex dystrophy and degree of secondary displacement.

Conclusion: This study validated the prognostic severity score of fractures of the lower extremity of the radius. The IRSS can be determined solely from the initial radiograms with or without traction. This score should be useful to modulate aggressive treatment as a function of the patient’s age and functional demands.