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Updated: May 13, 2026
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Transvaginal Mesh Insertion in the Ovine Model
Published on: July 27, 2017
Experimentally induced cam impingement in the sheep hip
Klaus A Siebenrock1, Ruth Fiechter, Moritz Tannast
1Department of Orthopedic Surgery, University of Bern, Inselspital, CH-3010 Bern, Switzerland. klaus.siebenrock@insel.ch
Summary
Researchers created cam-type femoro-acetabular impingement (FAI) in sheep hips, successfully reproducing cartilage damage similar to human FAI. The study found that this induced FAI leads to hip degeneration, which worsens over time with increased activity.
Area of Science:
- Orthopedics
- Comparative Pathology
- Biomechanical Engineering
Background:
- Sheep possess naturally non-spherical femoral heads, analogous to human cam-type deformities.
- Intertrochanteric varus osteotomy can experimentally induce cam-type femoro-acetabular impingement (FAI) in ovine models.
- Understanding FAI mechanisms is crucial for developing effective human treatments.
Purpose of the Study:
- To determine if experimentally induced cam-type FAI in an ovine model reproduces macroscopic cartilage lesions and elevated Mankin scores (MS).
- To investigate if the MS increases with prolonged ambulatory periods in the ovine model.
- To validate the ovine model for studying cam-type FAI and associated hip degeneration.
Main Methods:
- Unilateral intertrochanteric varus osteotomy was performed on sixteen sheep, with contralateral hips serving as controls.
- Sheep were sacrificed at 14, 22, 30, and 38 weeks post-surgery to assess outcomes.
- Macroscopic chondrolabral alterations were evaluated, and Mankin scores (MS) were determined via histochemical staining.
Main Results:
- A significantly higher incidence of macroscopic chondrolabral lesions was observed in the impingement zones of operated hips.
- Operated hips exhibited significantly higher Mankin scores in both acetabular and femoral cartilage.
- Mankin scores demonstrated a progressive increase correlating with longer ambulatory periods.
Conclusions:
- Cam-type FAI can be reliably induced in an ovine in vivo model.
- This model successfully replicates localized chondrolabral degeneration observed in human hip FAI.
- The ovine model provides a valuable platform for investigating the pathogenesis and potential treatments of cam-type FAI.
