title: First-time systematic postoperative clinical assessment of a minimally invasive approach for lumbar ventrolateral vertebroplasty in the large animal model sheep.
abstract: Large animal models are highly recommended for meaningful preclinical studies, including the optimization of cement augmentation for vertebral body defects by vertebroplasty/kyphoplasty.
  
  
  
  The aim of this study was to perform a systematic characterization of a strictly minimally invasive in vivo large animal model for lumbar ventrolateral vertebroplasty.
  
  
  
  This is a prospective experimental animal study.
  
  
  
  Lumbar defects (diameter 5 mm; depth approximately 14 mm) were created by a ventrolateral percutaneous approach in aged, osteopenic, female sheep (40 Merino sheep; 6-9 years; 68-110 kg). L1 remained untouched, L2 was left with an empty defect, and L3 carried a defect injected with a brushite-forming calcium phosphate cement (CPC). Trauma/functional impairment, surgical techniques (including drill sleeve and working canula with stop), reproducibility, bone defects, cement filling, and functional cement augmentation were documented by intraoperative incision-to-suture time and X-ray, postoperative trauma/impairment scores, and ex vivo osteodensitometry, microcomputed tomography (CT), histology, static/fluorescence histomorphometry, and biomechanical testing.
  
  
  
  Minimally invasive vertebroplasty resulted in short operation times (28±2 minutes; mean±standard error of the mean) and X-ray exposure (1.59±0.12 minutes), very limited local trauma (score 0.00±0.00 at 24 hours), short postoperative recovery (2.95±0.29 hours), and rapid decrease of the postoperative impairment score to 0 (3.28±0.36 hours). Reproducible defect creation and cement filling were documented by intraoperative X-ray and ex vivo conventional/micro-CT. Vertebral cement augmentation and osteoconductivity of the CPC was verified by osteodensitometry (CPC>control), micro-CT (CPC>control and empty defect), histology/static histomorphometry (CPC>control and empty defect), fluorescence histomorphometry (CPC>control; all p<.05 for 3 and 9 months), and compressive strength measurements (CPC numerically higher than control; 102% for 3 months and 110% for 9 months).
  
  
  
  This first-time systematic clinical assessment of a minimally invasive, ventrolateral, lumbar vertebroplasty model in aged, osteopenic sheep resulted in short operation times, rapid postoperative recovery, and high experimental reproducibility. This model represents an optimal basis for standardized evaluation of future studies on vertebral augmentation with resorbable and osteoconductive CPC.
authors.affiliation: Chair of Orthopedics, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle," Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany; Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle", Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany. Electronic address: m.bungartz@krankenhaus-eisenberg.de.
authors.forename: Matthias
authors.initials: M
authors.lastname: Bungartz
authors.affiliation: Chair of Materials Science, Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, D-07743 Jena, Germany; Jena School for Microbial Communication (JSMC), Friedrich Schiller University Jena, Neugasse 23, D-07743 Jena, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Maenz
authors.affiliation: Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle", Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany.
authors.forename: Elke
authors.initials: E
authors.lastname: Kunisch
authors.affiliation: Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle", Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany.
authors.forename: Victoria
authors.initials: V
authors.lastname: Horbert
authors.affiliation: Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle", Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany.
authors.forename: Long
authors.initials: L
authors.lastname: Xin
authors.affiliation: Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle", Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany.
authors.forename: Francesca
authors.initials: F
authors.lastname: Gunnella
authors.affiliation: Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle", Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany.
authors.forename: Joerg
authors.initials: J
authors.lastname: Mika
authors.affiliation: Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle", Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany.
authors.forename: Juliane
authors.initials: J
authors.lastname: Borowski
authors.affiliation: Institute of Laboratory Animal Sciences and Welfare, Jena University Hospital, Dornburger Str. 23, D-07743 Jena, Germany.
authors.forename: Sabine
authors.initials: S
authors.lastname: Bischoff
authors.affiliation: Institute of Laboratory Animal Sciences and Welfare, Jena University Hospital, Dornburger Str. 23, D-07743 Jena, Germany.
authors.forename: Harald
authors.initials: H
authors.lastname: Schubert
authors.affiliation: Chair of Orthopedics, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle," Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany.
authors.forename: Andre
authors.initials: A
authors.lastname: Sachse
authors.affiliation: BAM Bundesanstalt für Materialforschung und - prüfung (BAM), Unter den Eichen 87, D-12205 Berlin, Germany.
authors.forename: Bernhard
authors.initials: B
authors.lastname: Illerhaus
authors.affiliation: BAM Bundesanstalt für Materialforschung und - prüfung (BAM), Unter den Eichen 87, D-12205 Berlin, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Günster
authors.affiliation: Chair of Materials Science, Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, D-07743 Jena, Germany.
authors.forename: Jörg
authors.initials: J
authors.lastname: Bossert
authors.affiliation: Chair of Materials Science, Otto Schott Institute of Materials Research, Friedrich Schiller University Jena, Löbdergraben 32, D-07743 Jena, Germany; Jena School for Microbial Communication (JSMC), Friedrich Schiller University Jena, Neugasse 23, D-07743 Jena, Germany; Jena Center for Soft Matter (JCSM), Friedrich Schiller University Jena, Humboldstr. 10, D-07743 Jena, Germany.
authors.forename: Klaus D
authors.initials: KD
authors.lastname: Jandt
authors.affiliation: Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle", Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany.
authors.forename: Raimund W
authors.initials: RW
authors.lastname: Kinne
authors.affiliation: Chair of Orthopedics, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle," Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany; Experimental Rheumatology Unit, Department of Orthopedics, Jena University Hospital, Waldkrankenhaus "Rudolf Elle", Klosterlausnitzer Str 81, D-07607 Eisenberg, Germany.
authors.forename: Olaf
authors.initials: O
authors.lastname: Brinkmann
mesh_terms: D000818:Animals; D001843:Bone Cements / Q000627:therapeutic use; D005260:Female; D008159:Lumbar Vertebrae / Q000601:surgery*; D019060:Minimally Invasive Surgical Procedures / Q000009:adverse effects / Q000379:methods*; D011183:Postoperative Complications; D012756:Sheep; D054854:Vertebroplasty / Q000009:adverse effects / Q000379:methods*
chemical_list: D001843:Bone Cements
keywords: Calcium phosphate cement; Large animal model; Minimal-invasive; Sheep; Ventrolateral; Vertebroplasty; Void defect