Metallic instrument debris: A source of third-body wear particles?

Polyethylene wear debris is considered an important factor in aseptic loosening of total joint arthroplasties. Particles of any hard material (third-body wear particles) trapped within the articulation have been shown to increase greatly the rate of polyethylene wear. Reported sources of third-body particles include bone-cement, metal debris from porous coatings, broken trochanteric wires or cables, and particles of bone. We have observed that small particles, just visible to the naked eye, occasionally are shed by the copper hammers commonly used in the United Kingdom during total joint arthroplasty. This phenomenon has been reported as the cause of an eye injury to the surgeon. The hypothesis that such debris is produced with sufficient frequency to represent a possible source of third-body wear particles has not been investigated previously, however. We performed a study that simulates the intraoperative use of orthopaedic hammers. The resultant particulate debris was collected and analyzed.