Long-Term Results of the Treatment of Mallet Finger Injuries: A Retrospective Analysis

Background. Unsatisfactory clinical outcomes and patient dissatisfaction with the functional and aesthetic results of treating a mallet finger remain a significant challenge, as there is a lack of consensus among specialists regarding the optimal treatment approach, depending on the specific injury type. The aim of the study — to retrospectively evaluate the efficacy of external immobilization, trans-articular fixation and percutaneous extension block pinning for different types of mallet finger injuries, and to identify factors that influence functional outcomes. Methods. In a retrospective single-center study, functional results of 120 patients treated for acute mallet finger injuries were analyzed according to the Crawford classification. Patient satisfaction with the treatment was also assessed, and factors influencing treatment outcomes were identified. Results. Depending on the type of injury among the study participants, excellent and good outcomes were achieved in 22 (25%) and 30 (34%) patients with type I injuries, while satisfactory and poor outcomes were observed in 26 (29.5%) and 10 (11.4%), respectively. Patients with IVB and IVC injuries mostly experienced poor outcomes in 13 (48.1%) and 2 (40%) cases with satisfactory outcomes in 11 (40.7%) and 3 (60%), respectively. The type of injury according to the Doyle classification system, treatment method, and initial nail phalanx extension deficiency had a significant impact on treatment outcomes. Most patients with type I injury received conservative treatment, whereas patients with an initial phalanx extension defect of 30 degrees or more often experienced satisfactory and poor outcomes with a residual extension defect of 15±5 degrees. In patients with type IVB and type IVC injuries, 40% underwent percutaneous extension block pinning. These patients were more likely to have residual deficit in extension more than 20±6°, a higher incidence of pain syndrome and flexion insufficiency in the distal interphalangeal joint. Conclusion. In the management of type I injuries, the most significant factor influencing the functional outcome is the degree of initial deformity. Surgical intervention for type I injuries using trans-articular fixation can improve clinical outcomes, but it is associated with a significant risk of infection-related complications. When performing percutaneous extension block pinning for IVB and IVC type injuries, it is essential to achieve adequate repositioning to prevent improper fusion and the development of deformity-related osteoarthritis in the distal interphalangeal joints.