Single blind, prospective, randomized controlled trial comparing dorsal aluminum and custom thermoplastic splints to stack splint for acute mallet finger

Abstract

Objective: To compare Stack, dorsal, and custom splinting techniques in people with acute type 1a or b mallet finger.

Design: Multi-center randomized controlled trial.

Setting: Outpatient hand therapy clinics (2 public hospitals and 1 private clinic).

Participants: Patients (N=64) with acute type 1a or b mallet finger.

Interventions: Prefabricated Stack splint (control), dorsal padded aluminum splint, or custom-made thermoplastic thimble splint. All were worn for 8 weeks continuously, with a 4 week graduated withdrawal and exercise program.

Main outcome measures: The primary outcome was extensor lag at 12 and 20 weeks. Secondary outcomes were incidence of treatment failure, complications, range of motion of the distal interphalangeal joint, pain (visual analog scale) patient compliance, and patient satisfaction.

Results: There was no difference in the primary outcome between groups at 12 or 20 weeks; however, the Stack and dorsal splints had significant rates of treatment failure (23.8% in both groups, compared to none in the thermoplastic group; P=.04). There was a medium negative correlation between patient compliance and degree of extensor lag. No significant differences between groups were observed for patient satisfaction or pain.

Conclusions: As splints for mallet finger must be worn continuously for 6 to 8 weeks, and compliance correlates with favorable outcomes, treating practitioners must ensure the splint provided is robust enough for daily living requirements and does not cause complications, which are intolerable to the patient. In this study, no extensor lag difference was found between the 3 splint types, but custom-made thermoplastic splints were significantly less likely to result in treatment failure.

Trial registration: ClinicalTrials.gov NCT00310570.