Assessment of fracture healing by vibration

The wave signal from percussion of a bone (i.e. percussion-note) has been used to evaluate the extent of bony consolidation after fracture. Forty-one cases with a fresh tibial fracture and eight cases of delayed union of the tibia were investigated. The medial malleolus of the tibia was struck with a tapper and the vibration signal was picked up at the medial region of the tibial tuberosity. The changes in the signal waveform of the percussion-note with time were investigated. As healing proceeds, the signal waveform of the fractured bone approaches that of intact bone. In cases of delayed union, the character of the wave does not improve sufficiently with time. The authors are convinced that this is a promising new method for the early diagnosis of delayed union.