Radiographic changes in algodystrophy of the hand.

It is not certain to what extent the radiographic features of post-traumatic algodystrophy can be differentiated from disuse atrophy following trauma. A semi-quantitative scoring system has been devised, grading the dominant features seen on radiography in both conditions following Colles' fracture. The technique had intra- and inter-observer errors of 14% and 17% respectively. When applied prospectively 7 weeks after Colles' fractures, there was a significantly greater score in patients with algodystrophy (p less than 0.001) than those without. Analysis of the scores was performed to identify a score for the optimal identification of algodystrophy. At a score of four or greater, 87.5% of patients with algodystrophy were positively identified with a positive predictive value of 83%. It is suggested that use of this scoring system will aid in the early diagnosis of algodystrophy.