순간중심 고정식 및 이동식 인공디스크 적용에 대한 유한요소 모델을 이용한 생체역학적 분석

다국어 초록 (Multilingual Abstract)

Although several artificial disc designs have been developed for the treatment of discogenic low back pain, biomechanical changes with its implantation were rarely studied. To evaluate the effect of artificial disc implantation on the biomechanics of functional spinal unit, a nonlinear three-dimensional finite element model of L4-L5 was developed with 1-mm CT scan data. Biomechanical analysis was performed for two different types of artificial disc having constrained and unconstrained instant center of rotation(ICR), ProDisc and SB Charite III model. The implanted model predictions were compared with that of intact model. Angular motion of vertebral body, forces on the spinal ligaments and facet joint, and stress distribution of vertebral endplate for flexion-extension, lateral bending, and axial rotation with a compressive preload of 400 N were compared. The implanted model showed increased flexion-extension range of motion compared to that of intact model. Under 6Nm moment, the range of motion were 140%, 170% and 200% of intact in SB Charite III model and 133%, 137%, and 138% in ProDisc model. The increased stress distribution on vertebral endplate for implanted cases could be able to explain the heterotopic ossification around vertebral body in clinical observation. As a result of this study, it is obvious that implanted segment with artificial disc suffers from increased motion and stress that can result in accelerated degenerated change of surrounding structure. Unconstrained ICR model showed increased in motion but less stress in the implanted segment than constrained model.

참고문헌 (Reference)

1 De Kleuver, M, "Total Disc Replacement for Chronic Low Back pain: background and a Systematic Review of the Literature" 12 : 108-116, 2003

2 Dooris,A.P, "Load-sharing between Anterior and Posterior Elements in Lumbar Motion Segment Implanted with an Artificial Disc" Spine 26 : 122-129, 2001

3 Lemaire, J.P, "Intervetevral Disc Prosthesis. Results and Prospects for the Year 2000" 64-76, 1997

4 Rohlmann,A, "Effect of Total Disc Replacement with ProDisc on Intersegmental Rotation of the Lumbar Spine" Spine 30 : 738-743, 2005

5 McAfee,P.C, "Classification of Heterotopic Ossification in Artificial Disk Replacement" 16 : 384-389, 2003

6 Btter-Janz,K.,Schellnack,K, "Biomechanics of the SB Charit Lumbar Intervertebral Disc Endoprosthesis" 13 : 173-176, 1989.

7 Cunningham, B.W, "Biomechanical Evaluation of Total Disc Replacement Arthroplasty An in Vitro human Cadaveric Model" 28 : 110-117, 2004

8 Kim,Y.E, "Analysis of Dural-sac Occlusion in a Lumbar Spinal Motion Segment FE Model" 5 : 243-252, 2001

9 "* 저자 1의 소속"