Hammering sound frequency analysis and prevention of intraoperative periprosthetic fractures during total hip arthroplasty.

Adequate fixation at the time of cementless stem implantation depends on the operator's experience. An objective evaluation method to determine whether the stem has been appropriately implanted may be helpful. We studied the relationship between the hammering sound frequency during stem implantation and internal stress in a femoral model, and evaluated the possible usefulness of hammering sound frequency analysis for preventing intraoperative fracture.

Hammering force during cementless total hip arthroplasty and risk of microfracture.

During cementless stem fixation, impaction of the stem is occasionally complicated by bony injuries. Small fractures not visible to the eye during surgery or on post-operative radiographs may remain undetected, and the incidence of such injuries may be underestimated. Employing the same techniques as those employed during total hip arthroplasty, we implanted cementless stems into artificial femora, with equivalent mechanical characteristics to living femora.