Abstract
Object. Interspinous devices are widely used for the treatment of lumbar stenosis. The DIAM spinal stabilization system (Medtronic, Ltd.) is an interspinous implant made of silicone and secured in place with 2 laces. The device can be implanted via posterior access with the sacrifice of the supraspinous ligament (SSL) or via lateral access with preservation of the ligament. The aim of the present work was to evaluate the role of the laces, the SSL, and the device size and positioning to determine the device's ability in reducing segmental lordosis and in stabilizing motion. Methods. Biomechanical tests were performed in flexion and extension on 8 porcine spines implanted with the DIAM either with or without the laces and the SSL. A finite element model of the human L4-5 spine segments was also created and used to test 2 sizes of the device implanted in 2 different positions in the anteroposterior direction. Results. Implantation of the DIAM induced a shift toward kyphosis in the neutral position. Laces, the SSL, and device size and placement had a significant influence on the neutral position, the stiffness of the implanted spine, and the positions of the instantaneous centers of rotation. Conclusions. The shift of the neutral position toward kyphosis may be beneficial in reducing symptoms of spinal stenosis such as radicular pain, sensation disturbance, and loss of strength in the legs. The authors recommend preservation of the SSL and the use of the fixation laces, given their relevant mechanical role. Choosing the proper device size and placement should be achieved by using a correct surgical technique.
| Original language | English |
|---|---|
| Pages (from-to) | 568-575 |
| Number of pages | 8 |
| Journal | Journal of Neurosurgery: Spine |
| Volume | 13 |
| Issue number | 5 |
| DOIs | |
| Publication status | Published - Nov 2010 |
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Keywords
- Dynamic stabilization
- Interspinous implant
- Lumbar stenosis
- Spine biomechanics
ASJC Scopus subject areas
- Clinical Neurology
- Surgery
- Neurology
Cite this
Spine stability after implantation of an interspinous device : An in vitro and finite element biomechanical study - Laboratory investigation. / Anasetti, Federica; Galbusera, Fabio; Aziz, Hadi N.; Bellini, Chiara M.; Addis, Alessandro; Villa, Tomaso; Teli, Marco; Lovi, Alessio; Brayda-Bruno, Marco.
In: Journal of Neurosurgery: Spine, Vol. 13, No. 5, 11.2010, p. 568-575.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Spine stability after implantation of an interspinous device
T2 - An in vitro and finite element biomechanical study - Laboratory investigation
AU - Anasetti, Federica
AU - Galbusera, Fabio
AU - Aziz, Hadi N.
AU - Bellini, Chiara M.
AU - Addis, Alessandro
AU - Villa, Tomaso
AU - Teli, Marco
AU - Lovi, Alessio
AU - Brayda-Bruno, Marco
PY - 2010/11
Y1 - 2010/11
N2 - Object. Interspinous devices are widely used for the treatment of lumbar stenosis. The DIAM spinal stabilization system (Medtronic, Ltd.) is an interspinous implant made of silicone and secured in place with 2 laces. The device can be implanted via posterior access with the sacrifice of the supraspinous ligament (SSL) or via lateral access with preservation of the ligament. The aim of the present work was to evaluate the role of the laces, the SSL, and the device size and positioning to determine the device's ability in reducing segmental lordosis and in stabilizing motion. Methods. Biomechanical tests were performed in flexion and extension on 8 porcine spines implanted with the DIAM either with or without the laces and the SSL. A finite element model of the human L4-5 spine segments was also created and used to test 2 sizes of the device implanted in 2 different positions in the anteroposterior direction. Results. Implantation of the DIAM induced a shift toward kyphosis in the neutral position. Laces, the SSL, and device size and placement had a significant influence on the neutral position, the stiffness of the implanted spine, and the positions of the instantaneous centers of rotation. Conclusions. The shift of the neutral position toward kyphosis may be beneficial in reducing symptoms of spinal stenosis such as radicular pain, sensation disturbance, and loss of strength in the legs. The authors recommend preservation of the SSL and the use of the fixation laces, given their relevant mechanical role. Choosing the proper device size and placement should be achieved by using a correct surgical technique.
AB - Object. Interspinous devices are widely used for the treatment of lumbar stenosis. The DIAM spinal stabilization system (Medtronic, Ltd.) is an interspinous implant made of silicone and secured in place with 2 laces. The device can be implanted via posterior access with the sacrifice of the supraspinous ligament (SSL) or via lateral access with preservation of the ligament. The aim of the present work was to evaluate the role of the laces, the SSL, and the device size and positioning to determine the device's ability in reducing segmental lordosis and in stabilizing motion. Methods. Biomechanical tests were performed in flexion and extension on 8 porcine spines implanted with the DIAM either with or without the laces and the SSL. A finite element model of the human L4-5 spine segments was also created and used to test 2 sizes of the device implanted in 2 different positions in the anteroposterior direction. Results. Implantation of the DIAM induced a shift toward kyphosis in the neutral position. Laces, the SSL, and device size and placement had a significant influence on the neutral position, the stiffness of the implanted spine, and the positions of the instantaneous centers of rotation. Conclusions. The shift of the neutral position toward kyphosis may be beneficial in reducing symptoms of spinal stenosis such as radicular pain, sensation disturbance, and loss of strength in the legs. The authors recommend preservation of the SSL and the use of the fixation laces, given their relevant mechanical role. Choosing the proper device size and placement should be achieved by using a correct surgical technique.
KW - Dynamic stabilization
KW - Interspinous implant
KW - Lumbar stenosis
KW - Spine biomechanics
UR - http://www.scopus.com/inward/record.url?scp=78149324166&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=78149324166&partnerID=8YFLogxK
U2 - 10.3171/2010.6.SPINE09885
DO - 10.3171/2010.6.SPINE09885
M3 - Article
VL - 13
SP - 568
EP - 575
JO - Journal of Neurosurgery: Spine
JF - Journal of Neurosurgery: Spine
SN - 1547-5654
IS - 5
ER -