title: Does impaction matter in hip resurfacing? A cadaveric study.
abstract: Eight pairs of fresh frozen human femora were prepared for hip resurfacing. One side of each pair was impacted gently, the other side vigorously. After implantation procedure, specimens were loaded in a material testing machine to the ultimate fracture load. Median impaction loads on the vigorously implanted side were 11,298N compared to 1374N on the gently implanted side. Failure loads in the high-impact group (median, 8873N) were significantly (P = .0078) reduced when compared with the low-impact group (median, 9237N). The study stresses that meticulous reaming of the femoral head and the pinhole is of tremendous importance. Remaining obstacles can lead to excessive loads, while attempting to enforce the correct seating of the implant. Only careful, slight tapping should be applied to ensure final seating.
authors.affiliation: Department of Orthopedic and Trauma Surgery, University of Cologne, Cologne, Germany.
authors.forename: Ulf J
authors.initials: UJ
authors.lastname: Schlegel
authors.forename: Stephan
authors.initials: S
authors.lastname: Rothstock
authors.forename: Jan
authors.initials: J
authors.lastname: Siewe
authors.forename: Karl H
authors.initials: KH
authors.lastname: Schiwy-Bochat
authors.forename: Peer
authors.initials: P
authors.lastname: Eysel
authors.forename: Michael M
authors.initials: MM
authors.lastname: Morlock
mesh_terms: D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000379:methods*; D001696:Biomechanical Phenomena; D002102:Cadaver; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D057068:Periprosthetic Fractures / Q000209:etiology / Q000517:prevention & control; D011475:Prosthesis Failure