Extension of the elbow and supracondylar fractures in children

We tested the hypothesis that children who sustain a supracondylar fracture have a greater range of elbow hyperextension than those with a fracture of the distal radius. Three observers made 358 measurements in 183 children (114 boys and 69 girl s). There mere 119 fractures of the distal radius and 64 supracondylar frac tures. Initially, the group with a supracondylar fracture appeared to have extensi on 1.7 degrees greater than that of the group with fracture of the distal r adius. On average, there was a maximum variation of 3 degrees between obser vers. After allowing for age, gender and observer, there was no significant difference between the groups, Our study had greater than 80% power to det ect a difference in hyperextension of 2 degrees at the 5% level with the ab ove observer variability. When age and gender are taken into account, any variation in the amount of hyperextension at the elbow is not sufficient to explain the occurrence of a supracondylar fracture.