title: Biomechanical comparison of intact lumbar lamb spine and endoscopic discectomized lamb spine.
abstract: OBJECTIVE
  This study aims to perform a biomechanical comparison of changes on motion segments after minimally invasive percutaneous endoscopically discectomized and intact spine and to investigate the effects of endoscopic discectomy on the lumbar spine of the lamb.
  
  
  METHODS
  Ten fresh-frozen lamb spines were used in this study. Percutaneous endoscopic discectomy was performed on each spine at L4-L5 level. The biomechanical tests for both intact spine and endoscopically discectomized spine were performed by using axial compression testing machine. The axial compression was applied to all specimens with a loading speed of 5 mm/min. 8400 N/mm moment was applied to each specimen to achieve flexion and extension motions, right and left bending through a specially designed fixture.
  
  
  RESULTS
  In axial compression and flexion tests, the specimens were more stable based on displacement values. The displacement values of discected spines were closer to the values of intact specimens. Comparing both groups, only displacement values of the left-bending anteroposterior test were significant (p≤0.05).
  
  
  CONCLUSIONS
  Percutaneous transforaminal endoscopic discectomy (PTED) has no biomechanical and clinical disadvantages. Endoscopic discectomy has also no stability disadvantages. Only anteroposterior displacement values of left bending test were statistically significant. We consider that the reason for such results were due to the fact that PTED was performed on the left side of all specimens.
authors: Department of Orthopedics and Traumatology, Tire State Hospital, 35900 Tire, İzmir, Turkey. akarakasli@mail.city.com
authors: Ahmet
authors: A
authors: Karakaşlı
authors: Didem Venüs
authors: DV
authors: Yıldız
authors: Erdem
authors: E
authors: Kumtepe
authors: Ceren
authors: C
authors: Kızmazoğlu
authors: Hasan
authors: H
authors: Havıtçıoğlu
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D001696:Biomechanical Phenomena; D017586:Diskectomy; D004724:Endoscopy; D008159:Lumbar Vertebrae / Q000502:physiology* / Q000601:surgery; D023421:Models, Animal; D012756:Sheep