title: Temperature control with internally applied cooling in solid material drilling: an experimental, biomechanical study.
abstract: OBJECTIVE
  The purpose of this study was to evaluate the different temperature levels while drilling solid materials and to compare different cooling solutions for possible temperature control. An additional purpose was to develop an internal cooling device which can be connected to routinely used manual drilling devices in trauma surgery.
  
  
  METHODS
  Drilling was performed on a straight hip stem implanted in bovine femora without cooling, with externally applied cooling and with a newly developed internal cooling device. Temperature changes were measured by seven thermocouples arranged near the borehole. Additionally, thermographic scans were performed during drilling.
  
  
  RESULTS
  Drilling without cooling leads to an immediate increase in temperature to levels of thermal osteonecrosis (over 200 °C). With externally applied cooling temperatures were decreased, but were still up to a tissue damaging 85 °C. Internally applied cooling led to a temperature decrease to tissue-preserving levels during the drilling procedure (24.7 °C).
  
  
  CONCLUSIONS
  Internal cooling with HPC-drillers lowered the measured temperatures to non-tissue damaging temperatures and should avoid structural tissue damage.
authors.affiliation: Trauma Department Hannover Medical School, MHH, Carl-Neuberg-Street 1, D-30625 Hannover, Germany. brand.stephan@mh-hannover.de
authors.forename: Stephan
authors.initials: S
authors.lastname: Brand
authors.forename: Johannes
authors.initials: J
authors.lastname: Klotz
authors.forename: Maximilian
authors.initials: M
authors.lastname: Petri
authors.forename: Max
authors.initials: M
authors.lastname: Ettinger
authors.forename: Thomas
authors.initials: T
authors.lastname: Hassel
authors.forename: Christian
authors.initials: C
authors.lastname: Krettek
authors.forename: Thomas
authors.initials: T
authors.lastname: Goesling
authors.forename: Friedrich-Wilhelm
authors.initials: FW
authors.lastname: Bach
mesh_terms: D000818:Animals; D002417:Cattle; D004867:Equipment Design; D006621:Hip Joint / Q000601:surgery; D006622:Hip Prosthesis; D008422:Materials Testing; D023421:Models, Animal; D009983:Orthopedic Equipment / Q000592:standards*; D009985:Orthopedics / Q000379:methods*; D013696:Temperature