Periacetabular cortical and cancellous bone mineral density loss after press-fit cup fixation: a prospective 7-year follow-up.
The impact of total hip arthroplasty on strain adaptive bone remodeling has been extensively analyzed by dual-energy x-ray absorptiometry. In this study, we present a prospective computed tomography-assisted study of periacetabular cortical and cancellous bone mineral density (in milligrams of calcium hydroxyapatite [CaHA] per milliliter, or mgCaHA/mL) changes 10 days and 1, 3, and 7 years after press-fit cup implantation for 38 hips in vivo. Cancellous bone mineral density decreased by Ø -63% ventral and Ø -85% dorsal to the cup; cortical bone mineral density, by Ø -22% ventral and Ø -18% dorsal to the cup. The presented periacetabular strain adaptive bone mineral density data are the most extensive of the current literature. Even the measured extensive cancellous bone mineral density loss was thus far of no clinical relevance because all cups showed radiographic signs of stable ingrowth.
Department of Orthopaedic Surgery, Friedrich Alexander University Erlangen-Nuremberg, Erlangen, Germany.
Rainer
R
Schmidt
Alexander Michael
AM
Kress
Melanie
M
Nowak
Raimund
R
Forst
Tobias Eckhard
TE
Nowak
Lutz Arne
LA
Mueller
D000077:Acetabulum / Q000000981:diagnostic imaging / Q000503:physiopathology*; D000328:Adult; D000368:Aged; D019644:Arthroplasty, Replacement, Hip / Q000295:instrumentation / Q000379:methods*; D015519:Bone Density / Q000502:physiology*; D016723:Bone Remodeling / Q000502:physiology; D001862:Bone Resorption / Q000503:physiopathology*; D005260:Female; D005500:Follow-Up Studies; D006622:Hip Prosthesis; D006801:Humans; D008297:Male; D008875:Middle Aged; D011183:Postoperative Complications / Q000503:physiopathology*; D011446:Prospective Studies; D011474:Prosthesis Design; D014057:Tomography, X-Ray Computed