[Clinical diagnosis of Colles fracture combined with dorsal subluxation of radial carpal joints].

OBJECTIVE

To study the criteria for evaluating Colles fracture combined with dorsal radiocarpal subluxation (DRS).

METHOD

Fifty cases of Colles fracture combined with DRS, 100 cases of simple Colles fracture without DRS, and 100 normal wrist joint controls were included. We analysed central point displacement and perpendicular line ratio on the lateral view X-ray. For comminuted and severely displaced fracture, central point displacement (CPD) was not adopted because of difficulties in identifying the central point of the articular surface. Perpendicular line ratio (PLR) was suggested.

RESULT

Prominent difference was seen in the CPDs and the PLRs between the Colles fracture combined with DRS group and the simple Colles fracture and the normal control group (P < 0.01). Prominent relevance between the CPD and the PLR was also found (P < 0.05).

CONCLUSION

Central point displacement and perpendicular line ratio can be regarded as the diagnostic criteria for Colles fracture combined with DRS. PLR is especially valuable when the central point is hard to be identified in very comminuted and severely displaced fractures. DRS is suggested when CPD is more than 2.5 mm and PLR is less than 0.76.