Fifth Metacarpal Neck Fractures: Outcome-influencing Factors

Abstract

Abstract Introduction Fifth metacarpal neck fractures are extremely common, but there is still no consensus regarding the ideal course of treatment.Volar angulation and shortening are decisive factors; however, there is still controversy about the cut-off values that translate into worse clinical results.The present study aims to answer these questions in order to provide additional data to aid in the clinical practice and decision making. Materials and Methods A retrospective study evaluated patients with fifth metacarpal fractures treated between 2013 and 2018. A total of 133 patients were included, with an average follow-up of 2 months. Surgery was performed in 21 patients, and 112 were treated conservatively. The radiological assessment of volar anguation and shortening was based in the first and last radiographs of the follow-up. The patients were contacted and submited to a questionnaire that included the Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) score and subjective evaluations of pain (Visual Analogue Scale, VAS), hand strength, stiffness and finger mobility, and cosmetic result. Results Surgery was more successful in reducing angulation than the conservative treatment, achieving more anatomic final values for angulation and shortening (p < 0.05). On the other hand, surgery seems to be associated with a higher notion of limited finger mobility (p = 0.02).Among patients treated conservatively, inicial angulations > 60° and final angulations > 50° were associated with worse cosmetic results (p = 0,039). Final shortening > 4 mm translated into a higher notion of stiffness and limited finger mobility (p = 0.034).More advanced age showed a correlation with higher scores on the VAS (p = 0.023) and QuickDASH (p < 0,001). Female patients (p = 0.02) were also associated with higher VAS scores. The overall satisfaction rate was of 97%. Conclusion Although globally the functional outcome of these fractures is very good, the present study reports several factors that should be considered when treating fifth metacarpal neck fractures.