A Trial of the Effect of 2-Step Orthosis Treatment for Mallet Finger Fractures

Abstract

Context: Many patients report poor therapeutic outcomes following mallet finger fracture surgery. A more reliable technique is urgently needed. Objective: To present a novel treatment for mallet finger fractures using a 2-step orthosis method. Design: Prospective, observational study. Setting: Hospital. Participants: Patients with mallet finger fractures. Interventions: The finger is fixed with splints for 6 weeks, including 3 weeks for the proximal interphalangeal joint in the flexion position and the distal interphalangeal joint in the hyperextension position (first splint) and 3 weeks for the distal interphalangeal joint in the hyperextension position (second splint). Up to week 8, the second splint was attached at night and during physical exertion. Main Outcome Measures: Crawford criteria, Abouna–Brown criteria, bone fusion, grip strength, Doyle classification, Ishiguro classification. Results: Sufficient bone fusion was achieved 12 weeks after fixation; at which time, the range of motion with the distal interphalangeal joint flexed, and extended in the 3 patients was 50° and 0°, 70° and −3°, and 60° and 0°, respectively. The right and left hand grip strengths in the 3 patients were 58 and 55 kg, 62 and 58 kg, and 31 and 29 kg, respectively; there were no problems with respect to function or work. The first 2 patients could start sports again with partial return after 1 week and complete return after 12 weeks and 8 weeks, respectively. For the third patient, rehabilitation was complete after 16 weeks. Evaluation of the fracture sites based on the Crawford criteria showed the condition to be perfect, and evaluation based on the Abouna–Brown criteria showed success. Conclusions: This method provides satisfactory fixation and can prevent proximal interphalangeal joint contracture. Favorable long-term outcomes were confirmed in all patients, suggesting that this method may be effective for previously untreated mallet finger fractures with little displacement.