Our primary objective was to determine the effectiveness of 3 immobilization methods (circumferential casting [CC], volar–dorsal splinting [VDS] and modified sugar-tong [MST] splinting) in maintaining the position of displaced distal radius fractures after successful closed reduction. Our secondary objective was to assess long-term functional outcomes associated with immobilization with fibreglass splinting versus standard CC in patients maintaining initial nonoperative reductions.

We conducted a prospective randomized single-blind controlled trial in patients over 18 years of age who presented to the emergency department with a displaced fracture of the distal radius requiring closed reduction. The primary outcome was loss of reduction (defined as radiologic slippage or the need for surgical fixation during the 3–4 week primary immobilization period after initial successful reduction). Secondary outcomes included DASH (disabilities of the arm, shoulder and hand) score, return to work, activities of daily living, wrist pain, range of motion and grip strength assessed at 8 weeks and 6 months.

Thirty participants were randomly assigned to receive MST splinting, 31 to receive VDS and 40 to receive CC. Baseline characteristics were similar among groups. Radiographic loss of reduction occurred in 16% (95% confidence interval [CI] 3.1%–28.9%) of participants in the VDS group, 20% (95% CI 7.6%–32.4%) in the CC group and 30% (95% CI 13.6°%–46.4°%) in the MST splinting group (p = 0.17). Based on multivariate analysis of variance, functional outcomes at 8 weeks were similar among groups (p = 0.89). DASH scores at 8 weeks and 6 months were similar among groups, based on 1-way analysis of variance (p > 0.25).

Rates of loss in anatomic position were not statistically significant among the 3 types of dressings used. However, there was a clinically important trend of increased loss of reduction with the use of MST splinting. Functional outcomes at 8 weeks and 6 months were not significantly different between CC, VDS and MDS splinting. Ease of application and familiarity with use should guide clinical decisions when choosing a dressing type for displaced Colles fractures.