Orthotic Intervention with Custom-made Thermoplastic Material in Acute and Chronic Mallet Finger Injury: A Comparison of Outcomes

To compare the effect of using custom-made orthosis on improving extension lag and reducing disability in acute and chronic mallet fingers. We recruited 51 patients with acute or chronic Doyle type-1 mallet fingers, who were provided with a custom-made thermoplastic anti-mallet finger orthosis to wear full-time for 6 weeks and an additional 2 weeks at nighttime. The primary outcome, extension lag, was assessed at enrollment as well as six- and twelve-week followups. Secondary outcomes included disability and satisfaction, which were evaluated using the Disability of the Arm, Shoulder, and Hand questionnaire at enrollment and 12 weeks, and a satisfaction scale at 12 weeks follow-up. Data analysis was conducted using univariate analysis of variance (ANOVA), one-way repeated measure mixed model analysis of covariance (ANCOVA), and independent sample t-test. A total of 43 participants, 25 acute and 18 chronic mallet fingers, completed the 12-week evaluation. The study found no significant difference between the two groups in terms of improvement in extension lag at either follow-up time point (P=0.21). Disability improved in both the acute and chronic groups at follow-up (P<0.05). Additionally, both groups expressed satisfaction with the treatment outcome, and no statistically significant difference was observed (t=0.173, P=0.51). We could not identify any clinically significant difference between the two groups in regard to extension lag, disability, or satisfaction at follow-up. Notably, 96% of the patients in the acute group and 88% of the patients in the chronic group demonstrated good to excellent outcomes.  Orthotic intervention with custom-made thermoplastic material in acute and chronic mallet fingers improved extension lag and disability, and both groups were satisfied with the treatment outcomes. The findings of our study indicated that patients with chronic mallet fingers benefited from orthotic interventions in the same way that patients with acute mallet fingers did. Level of evidence: II