Biomechanical Comparison of Fifth Carpometacarpal Fusion Methods: Kirschner Wires Versus Plate and Screws

Abstract

Background:Fractures and dislocations of the base of the fifth metacarpal can lead to arthritis of the fifth carpometacarpal (CMC) joint. For patients who are symptomatic and fail conservative management, arthrodesis of the fifth CMC joint can be offered. The fusion can be performed using Kirschner wires (K-wires), but can lead to complications such as pin tract infection and pin migration. A low-profile locking plate may represent an attractive alternative. The purpose of this study was to compare the biomechanical stability of these 2 fusion techniques.Methods:Twelve fresh frozen cadaver hands were divided into 2 groups. The first group underwent fixation of the fifth CMC joint using 2 1.6 mm (0.062 inches) diameter K-wires in a cross-pin configuration. The second group underwent fixation using a 2.0 mm locking plate with 2 locking screws in the hamate and 3 nonlocking screws in the fifth metacarpal shaft. The specimens were then loaded in extension until failure.Results:The stiffness was 15.0±7.2 N/mm for the K-wire group and 14.7±6.0 N/mm (mean±SD) for the plate group (P=0.9366). The peak loads were 62.5±40.0 N and 64.6±24.8 N for K-wire and plate groups, respectively (P=0.9181). The energy to peak load was 294±281 N mm for the K-wire group and 418±190 N mm for the plate group (P=0.3904).Conclusions:Fifth CMC fusion using either K-wires or plate and screws showed no significant difference in stiffness, peak load, and energy to peak load. These results suggest the 2 methods provide similar biomechanical stability.

Management of Fifth Metacarpal Neck Fracture (Boxer's Fracture): A Literature Review

“…However, a focused study found no significant differences in the peak load and stiffness profile of the bone for fixation with plate and screw versus K-wires. The study, however, only focused on the CMC joint fixation using cadaveric bones [ 31 ]. Other potential benefits of the plate and screw fixation include ease of fixation when there is significant comminution is present or there are multiple metacarpal neck fractures [ 24 ].…”

Arthrodesis for Carpometacarpal Joint Arthritis: A Systematic Review

“…31 When compared to other fixation methods such as plate and screw, K-wire may result in less stability and delayed rehabilitation given its lesser rigidity and lack of permanent fixation. 32,33 Nonunion has been associated with a need for additional surgery in some cases, but also with higher postoperative DASH scores. 31 Peritrapezial arthritis is another known complication of arthrodesis.…”

Comparative study on the effectiveness of bone grafting for arthrodesis of the thumb carpometacarpal arthritis

“…(2015) showed a higher nonunion rate with K-wires compared with screws and staples. Compared with other fixation methods, such as screws and plates, K-wire may result in less stability due to its lower rigidity and lack of permanent fixation (Dreyfuss et al., 2019; Singh et al., 2015; Yoshida et al., 2018). In this study, the main surgical methods were K-wire fixation in the bone grafting group and TBW and screw fixation in the non-bone grafting group.…”

“…Forseth and Stern (2003) reported no difference in nonunion rates between K-wire and plate fixation, whereas Singh et al (2015) showed a higher nonunion rate with K-wires compared with screws and staples. Compared with other fixation methods, such as screws and plates, K-wire may result in less stability due to its lower rigidity and lack of permanent fixation (Dreyfuss et al, 2019;Singh et al, 2015;Yoshida et al, 2018).…”