Hammering K-wires is Superior to Drilling with Irrigation

Cooling during drilling Kirschner wires is not always effective in preventing thermal related damage. In this study, we used a human in vitro model and compared temperature elevation, insertion time, and extraction force between three Kirschner wire insertion methods—drilling with and without irrigation and pneumatic hammering. Forty five Kirschner wires were inserted into 15 fresh human cadaver metacarpals. All three insertion methods were applied in each metacarpal. Drilling without irrigation resulted in a temperature elevation of 67.25 ± 5.4 ºC with significantly lower values for drilling with irrigation (4.15 ± 0.6 ºC) and pneumatic hammering (31.52 ± 3.4 ºC). The insertion time for pneumatic hammering (47.63 ± 8.8 s) was significantly lower compared to drilling without irrigation (263.16 ± 36.5 s) and drilling with irrigation (196.10 ± 28.5 s). Extraction forces after drilling without irrigation, drilling with irrigation, and pneumatic hammering were 39.85 ± 4.1 N, 57.81 ± 6.5 N, and 62.23 ± 6.7 N, respectively. Pneumatic hammering is superior to drilling without irrigation, especially when irrigation is not possible.