title: Intraoperative mechanical measurement of bone quality with the DensiProbe.
abstract: Reduced bone stock can result in fractures that mostly occur in the spine, distal radius, and proximal femur. In case of operative treatment, osteoporosis is associated with an increased failure rate. To estimate implant anchorage, mechanical methods seem to be promising to measure bone strength intraoperatively. It has been shown that the mechanical peak torque correlates with the local bone mineral density and screw failure load in hip, hindfoot, humerus, and spine in vitro. One device to measure mechanical peak torque is the DensiProbe (AO Research Institute, Davos, Switzerland). The device has shown its effectiveness in mechanical peak torque measurement in mechanical testing setups for the use in hip, hindfoot, and spine. In all studies, the correlation of mechanical torque measurement and local bone mineral density and screw failure load could be shown. It allows the surgeon to judge local bone strength intraoperatively directly at the region of interest and gives valuable information if additional augmentation is needed. We summarize methods of this new technique, its advantages and limitations, and give an overview of actual and possible future applications.
authors.affiliation: Department of Orthopaedic Surgery, University of Bern, Inselspital, Bern, Switzerland. Electronic address: sven.hoppe@insel.ch.
authors.forename: Sven
authors.initials: S
authors.lastname: Hoppe
authors.affiliation: Department of Orthopaedic Surgery, University of Bern, Inselspital, Bern, Switzerland; Department of Traumatology, Kantonsspital Baselland, Laufen, Switzerland.
authors.forename: Michael
authors.initials: M
authors.lastname: Uhlmann
authors.affiliation: AO Research Institute, Biomechanical Services, AO Foundation, Davos, Switzerland.
authors.forename: Robert
authors.initials: R
authors.lastname: Schwyn
authors.affiliation: Department of Traumatology, University Hospital Basel, Basel, Switzerland.
authors.forename: Norbert
authors.initials: N
authors.lastname: Suhm
authors.affiliation: Department of Orthopaedic Surgery, University of Bern, Inselspital, Bern, Switzerland.
authors.forename: Lorin M
authors.initials: LM
authors.lastname: Benneker
mesh_terms: D015519:Bone Density; D057186:Comparative Effectiveness Research; D003720:Densitometry / Q000295:instrumentation / Q000379:methods; D019719:Diagnostic Equipment; D004867:Equipment Design; D005592:Fracture Fixation / Q000379:methods; D050723:Fractures, Bone / Q000150:complications / Q000601:surgery*; D006801:Humans; D007430:Intraoperative Care / Q000295:instrumentation / Q000379:methods; D007431:Intraoperative Complications / Q000517:prevention & control*; D008422:Materials Testing; D010024:Osteoporosis / Q000150:complications / Q000175:diagnosis*; D011183:Postoperative Complications / Q000517:prevention & control*
keywords: Bone strength; DensiProbe; implants failure; mechanical measurement; osteoporosis