A novel method for prevention of intraoperative fracture in cementless hip arthroplasty: vibration analysis during femoral component insertion.

Emerging minimally invasive surgery (MIS) techniques in hip arthroplasty heralded an increase in intraoperative femoral periprosthetic fractures, likely due to diminished visibility, auditory, and tactile feedback. This study attempts to identify a method to supplement the surgeon's tactile and auditory senses by analyzing vibration characteristics during femoral component impaction. A cementless femoral component was instrumented with accelerometers and a piezoelectric (PZT) patch. Data was obtained during implant impaction into replicate femurs. Acceleration measurements were obtained and signal processing techniques were applied. Metrics were analyzed from PZT excitation data. The two most correlative indices are the frequency of the anti-resonance in the 10.5 to 12 kHz band and the peak magnitude in the 9 to 11 kHz band. Both demonstrate good convergence as the prosthesis is inserted. Impact test data revealed the sum of the acceleration divided by the sum of the impact force demonstrates good convergence with implant insertion. This pattern of convergence indicates these two indices may demonstrate the ability to accurately predict optimal implant seating. This methodology is promising and has the potential to enable intraoperative determination of maximal femoral component seating and provide the surgeon valuable information to potentially prevent intraoperative fractures.