Factors affecting healing following percutaneous intramedullary fixation of metacarpal fractures

Although percutaneous intramedullary nailing of metacarpal fractures is a straightforward and reliable technique, it is not without complications, and patients experience different outcomes. This study analyzed factors affecting fracture healing time and complication rates in patients who underwent percutaneous intramedullary fixation of metacarpal fractures. This study was a retrospective review of the 25 patients who underwent retrograde percutaneous Kirschner wire (K-wire) nailing for fracture of the metacarpal shaft or neck at a military hospital between May 2016 and October 2018. Correlation study and multiple regression analysis were performed to evaluate variables (age, smoking history in pack-years, body-mass index, fracture site, number of K-wires used) that affect time to bone union. Clinical features of patients with metacarpal neck fractures and those with metacarpal shaft fractures were also compared. The metacarpal shaft fractures (as opposed to metacarpal neck fractures) and higher number of K-wire used were associated with longer time to bone union. Mean union time was significantly longer for metacarpal shaft fracture (8.6 weeks) than for metacarpal neck fracture (6.1 weeks) and for patients who received more K-wires than for those who received less (regression coefficient 1.307). One patient suffered fixation failure and required revision operation, and another experienced superficial infection which was treated with intravenous antibiotics. Percutaneous intramedullary nailing is an effective technique for metacarpal fractures, but fracture site and number of K-wire used affect time to achieve bone union.