Session IX - Upper Extremity

Control of Forearm Rotation during Nonoperative Management of Colles' Fracture: A Prospective Randomized Controlled Trial

Abizar Aladin, BmedSci, BMBS, MRCS; Steven A. Earnshaw, MBChB, DM, FRCS; Christopher G. Moran, MD, FRCS, University Hospital, Nottingham, U.K.

Purpose: Displaced Colles' fractures are commonly treated with closed reduction and immobilization in a below-elbow Colles' plaster. This plaster allows full movement of the elbow, including forearm rotation. With this technique, up to 70% of fractures will show some re-displacement at fracture union. We hypothesized that blocking forearm rotation but allowing flexion/extension at the elbow with use of a modified sugar-tong cast would reduce the levels of re-displacement compared with a conventional Colles' cast. We tested this hypothesis in a prospective randomized controlled trial.

Methods: A total of 126 patients with 128 displaced Colles'-type fractures were randomized to treatment with either a conventional Colles' cast (63 patients) or modified sugar-tong cast (65 patients). All fractures were reduced using the Chinese finger-trap method. The groups did not differ in age, sex, side of injury, fracture grade, or displacement at presentation (P >0.1). The fractures were assessed radiographically by measurement of radial angle, dorsal tilt, and radial shortening immediately after manipulation and after 1 and 5 weeks. This study had 90% power to detect differences in mean angular deformities of 3, 2 mm of radial shortening, and 20% in failure rates.

Results: No significant differences in radiographic measurements were found between groups (P >0.05). If dorsal tilt less than 10° and radial shortening less than 5 mm were considered acceptable, the two techniques resulted in successful reduction of 92% and 88% of fractures. Re-displacement occurred in both groups: in 40% and 39% by 1 week and 69% and 66% by 5 weeks (Colles' and sugar-tong, respectively). The final dorsal angulation was 11.0 ± 4.3 and 8.7 ± 4.0. There was no significant difference in the failure rate between the two groups (P >0.1). Multivariate analysis showed that younger patients (<65 years) had significantly less re-displacement (P = 0.029), but the type of cast did not influence the radiological outcome, even in this sub-group.

Discussion: The ideal treatment for displaced Colles' fracture remains controversial. Final accurate anatomic alignment increases the chances of a good functional outcome. Closed manipulation achieves a good reduction in 90% of cases, but accurate reduction is often not maintained in a conventional Colles' plaster until fracture union. Traditional cast treatment requires immobilization of the joint above and below the fracture. The Colles' plaster allows rotation of the forearm, and we hypothesized that prevention of this movement would reduce the risk of fracture displacement. Our results in a randomised prospective trial have shown that there is no difference with respect to dorsal tilt, radial shortening, radial angle, or carpal malalignment, whatever cast is used for immobilization.

Conclusion: Prevention of forearm rotation after manipulation of displaced Colles' fracture offers no advantage over a conventional Colles' plaster.