Comparison of Intramedullary Screws, Plating, and K-Wires for Metacarpal Fracture Fixation: A Meta-analysis

Abstract

PURPOSE: Metacarpal fractures are common injuries with multiple options for fixation, including plating and screws, K-wires, and intramedullary screws. Our purpose was to compare outcomes, including DASH score, total active motion (TAM), grip strength, and rates of re-operation or infection, in metacarpal fractures treated with intramedullary screw fixation (IMF), K-wires, or plates/screws. METHOD: A systematic literature review using the MEDLINE Database was performed for studies investigating metacarpal fractures treated with IMF, plates/screw, or K-wires. We identified nine studies using IMF, eight using plates/screws, and 17 using K-wires. A meta-analysis using random or fixed effects models was performed to calculate pooled effect size estimates, controlling for heterogeneity between studies. Outcome measures included mean DASH scores, mean TAM, mean grip strength (percentage to contralateral), mean time to radiographic healing, and the proportion of patients with infection and re-operation. RESULTS: Patients with IMF of metacarpal fractures had significantly lower mean DASH scores at an average of 0.6 [95% CI: 0.2, 1.0] compared to both K-wire (7.4 [4.8, 9.9]) and plates/screws (9.8 [5.3, 14.3]) (both p<0.001). IMF also had significantly lower rates of reoperation at 4% [2%, 7%], compared to K-wires 11% [7%, 16%], p= 0.001 and plate/screw fixation at 11% [0.07, 0.17] p=0.01. Grip strength was significantly higher in IMF (104.4% [97.0, 111.8]) compared to K-wires (88.5%, [88.3, 88.7]) and plate/screws (90.3, [85.4, 95.2] (both p<0.001). There were no statistically significant differences in time to radiographic healing of evidence, mean TAM, or rates of infection. Mean OR time was similar between IMF (average of 21.0 minutes [10.4, 31.6]) and K-wires (20.8 minutes [14.0, 27.6]), but both were shorter compared to plate/screw fixation (average 52.6 minutes [33.1, 72.1]) with K wires being significantly shorter (p<0.001). Summary This meta-analysis compares outcomes of metacarpal fixation with IMF, K-wires, or plates/screws. IMF provided statistically significant lower DASH scores, higher grip strength, lower rates of re-operation, when compared to K-wires and plates/screws for fixation of metacarpal fractures. There were no statistically significant differences in rates of mean TAM, time to radiographic healing, or rates of infection between the 3 groups. OR time was lower for both IMF and K wires as compared to plates and screws, but only K wires had enough data points for significance. CONCLUSION: Intramedullary screw fixation of metacarpal fractures provides lower DASH scores, higher grip strength, and lower rates of re-operation when compared to K-wires and plates/screws.