Ventral Surgical Approach for an Intervertebral Disc Degeneration and Regeneration Model in Sheep Cervical Spine: Anatomic Technical Description, Strengths and LimitationsFunding This study was funded by the AO Foundation Collaborative Research Program Annulus Fibrosus Repair. The authors on this article are all Research Partners of the Collaborative Research Program Annulus Fibrosus Repair of the AO Foundation.
05 September 2018
27 March 2019
03 June 2019 (eFirst)
Objective Sheep are used as a large animal model for intervertebral disc research. However, for the ovine ventral surgical approach to the cervical disc, limited descriptions exist. We, therefore, give a detailed in vivo anatomical description of this approach in sheep for the use in intervertebral disc regeneration and degeneration models to increase the reproducibility of such interventions.
Materials and Methods Eighteen female Swiss white alpine sheep, with an age range of 2 to 4 years, were used. A ventral surgical access was performed to establish defined intervertebral disc punch defect from cervical levels C3/4 to C5/6. Cervical levels C2/3 and C6/7 were used as negative controls. Intraoperative findings, radiographical controls and postoperative clinical follow-up were documented and collected for this clinical report.
Results All sheep recovered rapidly from the surgical intervention. Two sheep developed wound seroma, which resorbed spontaneously. Two further sheep showed wound dehiscence within 3 days after surgery, which had to be revised. No clinical wound infections occurred and all sheep healed well and did not show any side effects related to the surgical procedure.
Conclusion The ventral surgical access to the ovine cervical spine is a safe and reliable procedure. The advantage of the cervical intervertebral disc is the easier surgical access and the increased disc height compared to the sheep lumbar spine. Since the ovine cervical intervertebral disc shows a high grade of similarities (e.g. molecular characteristics) compared to human discs, it is a promising degeneration and regeneration model for disc diseases.
The authors are not compensated and there are no other institutional subsidies, corporate affiliations or funding sources supporting this work unless clearly documented and disclosed. This project was performed at the AO Research Institute Davos, Davos, Switzerland.
Moritz C. Deml and Lorin M. Benneker contributed to conception of study, study design, acquisition of data, and data analysis and interpretation. Stephan Zeiter, Tanja Schmid and Daisuke Sakai contributed to conception of study, study design and acquisition of data. Christoph E. Albers and Sven Hoppe contributed to data analysis and interpretation. Moritz C. Deml, Stephan Zeiter, Christoph E. Albers, Sven Hoppe and Tanja Schmid drafted and revised the manuscript. All authors approved the submitted manuscript.
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