Intraoperative measurement of bone electrical potential: a piece in the puzzle of understanding fracture healing

Bone electrical potentials change with the force applied. Also, fracture alters the bone electrical potential, so it becomes more electronegative. These potentials have an important role in fracture healing, bone growth and remodelling. Literature data on the influence of fracture operative treatment on bone electrical potentials, and possible consequences of this influence, are sparse. The objective of this study was to establish a method of intraoperative bone potential measurement, and to try to find a correlation between electrical potential and fracture type, osteosynthesis method and prognosis.

52 patients with a pertrochanteric fracture were included in the study. Bone electrical potentials were measured intraoperatively using a thin Kirschner wire introduced through bone cortex at the selected point and pointed to opposite cortex, not penetrating it. Kirschner wires were connected using clamps to multimeter (YF-78 Multimeter) device. Neutral electrode (inductive rubber) was placed behind ipsilateral gluteus.

Near the fracture site potentials of -199 up to -267 mV were recorded. Mean measured potential of bone plate after fixation was -240 mV. Bone potentials correlated with the subtype of fracture and early mobilisation of patients.

Bone potentials, caused by fracture, can be measured intraoperatively; the operative procedure appears to influence their generation. Measured potentials depend on the fracture type, and could be correlated with prognosis.