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Anton E. Bowden - One of the best experts on this subject based on the ideXlab platform.
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Thoracolumbar spinal Ligaments exhibit negative and transverse pre-strain
Journal of the mechanical behavior of biomedical materials, 2013Co-Authors: Daniel J. Robertson, Gregory A. Von Forell, Jeremy Alsup, Anton E. BowdenAbstract:The present work represents the first reported bi-axial spinal Ligament pre-strain data for the thoracic and lumbar spine. Ligament pre-strain (in-situ strain) is known to significantly alter joint biomechanics. However, there is currently a lack of comprehensive data with regards to spinal Ligament pre-strain. The current work determined the pre-strain of 71 spinal Ligaments (30 anterior longitudinal Ligaments, 27 Supraspinous Ligaments and 14 interspinous Ligaments). The interspinous Ligament and the anterior longitudinal Ligament exhibited bi-axial pre-strain distributions, demonstrating they are not uniaxial structures. The Supraspinous Ligament frequently exhibited large amounts of negative pre-strain or laxity suggesting it makes no mechanical contribution to spinal stability near the neutral posture. Upon implementing multi-axial pre-strain results into a finite element model of the lumbar spine, large differences in spinal biomechanics were observed. These results demonstrate the necessity of accounting for Ligament pre-strain in biomechanical models. In addition, the authors present a unique experimental method for obtaining Ligament pre-strain that presents a number of advantages when compared to standard techniques.
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the lumbar Supraspinous Ligament demonstrates increased material stiffness and strength on its ventral aspect
Journal of The Mechanical Behavior of Biomedical Materials, 2013Co-Authors: Daniel J. Robertson, R. Willardson, D. Parajuli, A. Cannon, Anton E. BowdenAbstract:The present work represents the first reported quantified anisotropic, inhomogeneous material constitutive data for the human Supraspinous Ligament (SSL). Multi-axial material data from 30 human cadaveric SSL samples was collected from distinct locations (dorsal, midsection, and ventral). A structurally motivated strain-energy based continuum model was employed to characterize anisotropic constitutive parameters for each sample. The anisotropic constitutive response correlated well with the reported experimental data (R2>0.97). Results show that in the lumbar spine both the material stiffness and stress at failure were significantly higher in the ventral region of the SSL as compared with the dorsal region (p<0.05). In the along fiber direction a higher stiffness and stress at failure were observed when compared to the transverse direction. These results indicate that modeling spinal Ligaments using the hyperelastic line elements that have typically been used may be insufficient to capture their complex material response.
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The lumbar Supraspinous Ligament demonstrates increased material stiffness and strength on its ventral aspect
Journal of the mechanical behavior of biomedical materials, 2012Co-Authors: Daniel J. Robertson, R. Willardson, D. Parajuli, A. Cannon, Anton E. BowdenAbstract:The present work represents the first reported quantified anisotropic, inhomogeneous material constitutive data for the human Supraspinous Ligament (SSL). Multi-axial material data from 30 human cadaveric SSL samples was collected from distinct locations (dorsal, midsection, and ventral). A structurally motivated strain-energy based continuum model was employed to characterize anisotropic constitutive parameters for each sample. The anisotropic constitutive response correlated well with the reported experimental data (R2>0.97). Results show that in the lumbar spine both the material stiffness and stress at failure were significantly higher in the ventral region of the SSL as compared with the dorsal region (p
Moshe Solomonow - One of the best experts on this subject based on the ideXlab platform.
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Power spectra characteristics associated with static reflexive activation of the multifidus muscle in feline models
European Journal of Applied Physiology, 2008Co-Authors: Todor Arabadzhiev, Moshe Solomonow, Bing He Zhou, Nonna A. Dimitrova, G.v. DimitrovAbstract:The aim of the study was to track changes in the spectrum of electromyographic (EMG) signals recorded from the feline multifidus muscles during stretching of the Supraspinous Ligament. The Ligaments were exposed to external 40 N-tension for six consecutive trials of 10-min duration. Two experimental groups were formed, according to the rest periods supplied (10 or 20 min). EMG signals were recorded intramuscularly from the right multifidus muscles. The EMG signals from each trial were split into segments. For each segment, a representative averaged motor unit potential (AvMUP) was determined. The number of single MUPs averaged to obtain AvMUP was defined as muscular activity. The relative changes in a muscle fatigue index, median frequency as well as activity were analyzed. It was concluded that faster and powerful motor units are recruited firstly, in order to quickly provide stronger support to the spine and/or as a reaction to a minor damage of tissue. Depending on the applied rest periods, peripheral fatigue might be accumulated.
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Short rest periods after static lumbar flexion are a risk factor for cumulative low back disorder.
Journal of electromyography and kinesiology : official journal of the International Society of Electrophysiological Kinesiology, 2005Co-Authors: Amy Courville, Moshe Solomonow, Bing He Zhou, Paola Sbriccoli, Evalina L. BurgerAbstract:Abstract The objective of this work was to study the effect of rest periods of various durations applied between six 10-min sessions of static flexion on the development of cumulative low back disorder (CLBD). Three experimental groups of a feline model were used, and the rest duration between sequential static load periods was set to 5, 10, and 20 min, with a corresponding load-to-rest ratio of 2:1, 1:1 and 1:2, respectively. The reflex electromyographic (EMG) activity from the multifidus muscles and Supraspinous Ligament displacement (creep) were recorded during the flexion periods and over 7 h of rest following the load–rest cycles. It was found that a minor disorder developed in all the groups whereas a severe neuromuscular disorder including a delayed hyperexcitability was observed only in the group subjected to 5 min rest. The two-way ANOVA showed a significant effect of time post loading ( p p p p
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Neuromuscular dysfunction elicited by cyclic lumbar flexion.
Muscle & nerve, 2003Co-Authors: Lakiesha N Claude, B.-h. Zhou, Moshe Solomonow, Richard V. Baratta, Meng Ping ZhuAbstract:An attempt was made to develop an in vivo model that could explain the neurophysiological and biomechanical processes active in the development of the idiopathic low back disorder common in workers who perform repetitive lifting tasks in industry. Passive cyclic flexion of the feline lumbar spine at 0.1 HZ for 20 min resulted in creep of the Supraspinous Ligament and other lumbar viscoelastic tissues as well as spasms superimposed on a decreasing electromyogram (EMG) elicited reflexly from the multifidus muscles. Rest for 7 h did not allow full recovery of the viscoelastic creep; the multifidus EMG gradually increased with initial and delayed hyperexcitability. Increasing the peak load of the cyclic flexion resulted in larger creep in the passive tissues and required a longer time for recovery of reflex EMG activity and longer delayed hyperexcitability, but development of spasms and hyperexcitability was unaffected. It is conceivable that damage to the viscoelastic tissues elicits an inflammatory process that in turn triggers a transient neuromuscular disorder. The present findings provide a biomechanical and neurophysiological explanation for a common idiopathic low back disorder as well as for the development of a cumulative trauma disorder often seen in workers engaged in repetitive lumbar flexion.
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Neuromuscular disorders associated with static lumbar flexion: a feline model
Journal of Electromyography and Kinesiology, 2002Co-Authors: Moshe Solomonow, B.-h. Zhou, Richard V. Baratta, Y LuAbstract:Abstract Static flexion of the lumbar spine with constant load applied to the viscoelastic structures for 20 minutes and for 50 minutes resulted in development of spasms and inhibition in the multifidus muscles (e.g., deep erector spinae) and in creep of the Supraspinous Ligament in the feline model. The development of spasms and inhibition was not dependent on load magnitude. It is suggested that occupational and sports activities which require prolonged static lumbar flexion within the physiological range can cause a “sprain”-like injury to the Ligaments, which in turn reflexively induce spasms and inhibition in some erector spinae muscles. Such disorder may take a long time to recover, in the order of days to weeks, depending on the level of creep developed in the tissues.
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Neuromuscular neutral zones sensitivity to lumbar displacement rate.
Clinical biomechanics (Bristol Avon), 2001Co-Authors: B.s Elizabeth Eversull, Moshe Solomonow, Richard V. Baratta, E.e Bing He Zhou, Meng Ping ZhuAbstract:Abstract Objectives . To determine the displacement and tension thresholds (developed during anterior lumbar flexion) which trigger reflexive muscular activity in the multifidus muscles; their variability with the velocity of flexion; and the pattern of threshold variability across the lumbar spine. Design . An in-vivo study of the feline during passive lumbar flexion applied via the L-4/5 Supraspinous Ligament. Method . EMG from six pairs of intramuscular electrodes inserted in the L-1/2 to L-6/7 multifidus muscles was recorded while the lumbar spine was passively flexed to 75% of the physiological strain of the Supraspinous Ligament at rates of 17–100%/s. Three-dimensional models of tension threshold, flexion rate and lumbar levels were developed from the experimental data. Results . Displacement and tension thresholds were the lowest at the fastest flexion rate and gradually increased as flexion rates decreased. Electromyographic activity was detected at low thresholds at the center of the flexion and at gradually increasing thresholds at higher and lower lumbar segments. Conclusion . Multifidus reflexive muscular activity, which stabilize the spine, is triggered at a displacement and tension thresholds of 5–15% of the physiological range. Earlier activation of muscular activity occurs as the velocity of flexion increases. Earlier activation also occurs near the center of flexion. Relevance Sensory-motor neurological feedback maintains spine stability and is responsive to the velocity of lumbar motion. A neuromuscular silence exists in small lumbar movements in which spine stability is not protected by the musculature. Spine models constructed to predict risk factors could benefit from incorporating this new information.
Thomas J. Masaryk - One of the best experts on this subject based on the ideXlab platform.
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Thoracolumbar burst fractures: evaluation with MR imaging.
Radiology, 1995Co-Authors: Cheryl A. Petersilge, Sanford E Emery, Mini N. Pathria, Thomas J. MasarykAbstract:PURPOSE: To determine the frequency of posterior Ligamentous injury that occurs in patients with thoracolumbar burst fractures and to correlate Ligamentous disruption with radiographic appearance. MATERIALS AND METHODS: Magnetic resonance (MR) imaging examinations of 21 patients with 25 thoracolumbar burst fractures were retrospectively evaluated to determine spinal Ligament integrity. Radiographic and computed tomographic (CT) examinations were evaluated for interpediculate widening, midsagittal canal narrowing, posterior element fractures, and kyphosis; a radiographic assessment of posterior Ligamentous integrity was made. These findings were then correlated with the status of the spinal Ligaments. RESULTS: The patients were divided into two groups on the basis of the status of their Supraspinous Ligament (SSL). Six patients had disrupted SSLs, and 15 had intact SSLs. Radiographic and CT findings did not correlate with Supraspinous Ligament disruption. Radiographic indicators of posterior Ligamentous di...
Richard V. Baratta - One of the best experts on this subject based on the ideXlab platform.
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Neuromuscular dysfunction elicited by cyclic lumbar flexion.
Muscle & nerve, 2003Co-Authors: Lakiesha N Claude, B.-h. Zhou, Moshe Solomonow, Richard V. Baratta, Meng Ping ZhuAbstract:An attempt was made to develop an in vivo model that could explain the neurophysiological and biomechanical processes active in the development of the idiopathic low back disorder common in workers who perform repetitive lifting tasks in industry. Passive cyclic flexion of the feline lumbar spine at 0.1 HZ for 20 min resulted in creep of the Supraspinous Ligament and other lumbar viscoelastic tissues as well as spasms superimposed on a decreasing electromyogram (EMG) elicited reflexly from the multifidus muscles. Rest for 7 h did not allow full recovery of the viscoelastic creep; the multifidus EMG gradually increased with initial and delayed hyperexcitability. Increasing the peak load of the cyclic flexion resulted in larger creep in the passive tissues and required a longer time for recovery of reflex EMG activity and longer delayed hyperexcitability, but development of spasms and hyperexcitability was unaffected. It is conceivable that damage to the viscoelastic tissues elicits an inflammatory process that in turn triggers a transient neuromuscular disorder. The present findings provide a biomechanical and neurophysiological explanation for a common idiopathic low back disorder as well as for the development of a cumulative trauma disorder often seen in workers engaged in repetitive lumbar flexion.
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Neuromuscular disorders associated with static lumbar flexion: a feline model
Journal of Electromyography and Kinesiology, 2002Co-Authors: Moshe Solomonow, B.-h. Zhou, Richard V. Baratta, Y LuAbstract:Abstract Static flexion of the lumbar spine with constant load applied to the viscoelastic structures for 20 minutes and for 50 minutes resulted in development of spasms and inhibition in the multifidus muscles (e.g., deep erector spinae) and in creep of the Supraspinous Ligament in the feline model. The development of spasms and inhibition was not dependent on load magnitude. It is suggested that occupational and sports activities which require prolonged static lumbar flexion within the physiological range can cause a “sprain”-like injury to the Ligaments, which in turn reflexively induce spasms and inhibition in some erector spinae muscles. Such disorder may take a long time to recover, in the order of days to weeks, depending on the level of creep developed in the tissues.
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Neuromuscular neutral zones sensitivity to lumbar displacement rate.
Clinical biomechanics (Bristol Avon), 2001Co-Authors: B.s Elizabeth Eversull, Moshe Solomonow, Richard V. Baratta, E.e Bing He Zhou, Meng Ping ZhuAbstract:Abstract Objectives . To determine the displacement and tension thresholds (developed during anterior lumbar flexion) which trigger reflexive muscular activity in the multifidus muscles; their variability with the velocity of flexion; and the pattern of threshold variability across the lumbar spine. Design . An in-vivo study of the feline during passive lumbar flexion applied via the L-4/5 Supraspinous Ligament. Method . EMG from six pairs of intramuscular electrodes inserted in the L-1/2 to L-6/7 multifidus muscles was recorded while the lumbar spine was passively flexed to 75% of the physiological strain of the Supraspinous Ligament at rates of 17–100%/s. Three-dimensional models of tension threshold, flexion rate and lumbar levels were developed from the experimental data. Results . Displacement and tension thresholds were the lowest at the fastest flexion rate and gradually increased as flexion rates decreased. Electromyographic activity was detected at low thresholds at the center of the flexion and at gradually increasing thresholds at higher and lower lumbar segments. Conclusion . Multifidus reflexive muscular activity, which stabilize the spine, is triggered at a displacement and tension thresholds of 5–15% of the physiological range. Earlier activation of muscular activity occurs as the velocity of flexion increases. Earlier activation also occurs near the center of flexion. Relevance Sensory-motor neurological feedback maintains spine stability and is responsive to the velocity of lumbar motion. A neuromuscular silence exists in small lumbar movements in which spine stability is not protected by the musculature. Spine models constructed to predict risk factors could benefit from incorporating this new information.
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Multifidus spasms elicited by prolonged lumbar flexion.
Spine, 2000Co-Authors: Mathew Williams, B.-h. Zhou, Moshe Solomonow, Richard V. Baratta, Mitchel B. HarrisAbstract:Study design The electromyogram of the L1-L7 multifidus muscles of the in vivo cat were recorded while applying a prolonged steady displacement to the lumbar spine through the L4-L5 Supraspinous Ligament, simulating a moderate anterior flexion. Objective To demonstrate that tension-relaxation and laxity of the viscoelastic structures (Ligaments, discs, and capsules) induced by prolonged static flexion of the spine results in loss of reflexive muscular stabilizing activity and in muscular disorders that may lead to or are associated with low back pain. Summary of background Epidemiologic data show that prolonged loading of the spine, such as in some occupational activities, can cause low back pain and muscle spasms. Direct experimental evidence linking prolonged loading to a decrease in spinal stability, low back pain, and muscle spasms was not found. It was hypothesized, however, that mechanoreceptors in the viscoelastic structures, when strained, reflexively activate the multifidus muscles to maintain intervertebral stability; that the reflexive muscular activity decreases with stress-relaxation and laxity in the viscoelastic structures; and that when severe strain and possible damage of the viscoelastic structures occurs with time, nociceptive receptors elicit spasms in the musculature and possible pain. Methods The lumbar spine of seven in vivo cat preparations was displaced through the L4-L5 Supraspinous Ligament into moderate flexion that was steadily maintained for 50 minutes while intramuscular electromyograms were recorded from each of the multifidus muscles of L1-L2 through L6-L7. Load and electromyogram were continuously monitored and recorded. Five additional preparations were used as controls, in which dissection and recordings were identical, but the lumbar flexion was excluded. Results Prolonged flexion of the lumbar spine resulted in initial reflexive electromyogram from the multifidus muscles that decreased to approximately 5% of its initial value as tension-relaxation began in the viscoelastic structures within the first 3 minutes, after which, random and unpredictable electromyogram discharges (i.e., spasms) of high amplitude were recorded from different levels. In some preparations the spasms were present in L1-L4, and in others in all the levels. In other preparations the spasms were recorded only at L5 and L6. The onset of the spasms was also unpredictable, because they were initiated in some cases within 2-3 minutes after the spine was loaded. In other cases, the spasms were observed anytime during the test period and up to 20 minutes after the load was removed. Spasms were also observed in the spinalis and longissimus muscles. Conclusions Prolonged flexion of the lumbar spine results in tension-relaxation and laxity of its viscoelastic structures, loss of reflexive muscular activity within 3 minutes and electromyogram spasms in the multifidus and other posterior muscles.
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The Ligamento-muscular stabilizing system of the spine.
Spine, 1998Co-Authors: Moshe Solomonow, B.-h. Zhou, Mitchel B. Harris, Richard V. BarattaAbstract:Study design Electrical and mechanical stimulation of the lumbar Supraspinous Ligament of three patients with L4-L5 spinal deficits and of the feline model, respectively, was applied while recording electromyography on the multifidus muscles. Objectives To determine if mechanoreceptors in the human spine can reflexively recruit muscle force to stabilize the lumbar spine, and to demonstrate, in the feline model, that such Ligamento-muscular synergy is elicited by mechanical deformation of the lumbar Supraspinous Ligament (and possibly of other spinal Ligaments), the facet joint capsule, and the disc. Summary of background data The literature repeatedly confirms that Ligaments have only a minor mechanical role in maintaining spine stability, and that muscular co-contraction of anterior and posterior muscles is the major stabilizing mechanism of the spine. The literature also points out that various sensory receptors are present in spinal Ligaments, and that the Ligaments are innervated by spinal and autonomic nerves. Data that describe how Ligaments and muscles interact to provide stability to the spine were not found. Methods The Supraspinous Ligament at L2-L3 and L3-L4 was electrically stimulated in three patients undergoing surgery to correct deficits at L4-L5. Electromyography was performed from the multifidus muscles at L2-L3 and L3-L4, bilaterally. In 12 cats, the Supraspinous Ligaments from L1-L2 to L6-L7 were mechanically deformed, sequentially, while electromyography was performed from the multifidus muscles of the six levels. Loading of the Ligament was applied before and after each of the two vertebrae were externally fixed to prevent motion. Results Electromyograms were recorded from the multifidus muscles, bilaterally, in the two of the three patients, demonstrating a direct relationship to receptors in the Supraspinous Ligament. Electromyograms were recorded from the feline multifidus muscle with mechanical loading of the supraspinal Ligament at each of the L1-L2 to L6-L7 motion segments. In the free-spine condition the largest electromyographic discharge was present in the level of Ligament deformation, and lower electromyographic discharge was recorded in two rostral and caudal segments. After immobilizing any two vertebrae, loading of the Ligament resulted in electromyographic discharge in the muscles of the same level and at least one level above and/or below. Conclusions Deformation or stress in the Supraspinous Ligament, and possibly in other spinal Ligaments, recruits multifidus muscle force to stiffen one to three lumbar motion segments and prevent instability. Strong muscular activity is seen when loads that can cause permanent damage to the Ligament are applied, indicating that spastic muscle activity and possibly pain can be caused by Ligament overloading.
R Sobottke - One of the best experts on this subject based on the ideXlab platform.
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Research Article The Interspinous Spacer: A Clinicoanatomical Investigation
2016Co-Authors: Using Plastination, P Eysel, Juergen Koebke, R SobottkeAbstract:Copyright © 2012 Thomas Kaulhausen et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Purpose. The relatively new and less-invasive therapeutic alternative “interspinous process decompression device (IPD) ” is expected to result in improved symptoms of neurogenic intermittent claudication (NIC) caused by lumbar spinal stenosis. The aim of the study was to analyze IPD position particularly regarding damage originating from surgical implantation. Methods. Anatomic assessments were performed on a fresh human cadaver. For the anatomic examination, the lumbar spine was plastinated after implantation of the IPDs. After radiographic control, serial 4 mm thick sections of the block plastinate were cut in the sagittal (L1– L3) and horizontal (L3–L5) planes. The macroanatomical positioning of the implants was then analyzed. The insertion procedure caused only little injury to osteoLigamentous or muscular structures. The Supraspinous Ligament was completely intact, and the interspinous Ligaments were not torn as was initially presupposed. No osseous changes at the spinal processes were apparent. Contact of the IPD with the spinous processes was visible, so that sufficient biomechanical limitation of the spinal extension seems likely. Conclusions. Minimally invasive IPD implantation with accurate positioning in the anterior portion of the interspinous place is possible without severe surgical trauma. 1
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The Interspinous Spacer: A Clinicoanatomical Investigation Using Plastination
Minimally invasive surgery, 2012Co-Authors: T Kaulhausen, P Eysel, J Knifka, Kourosh Zarghooni, Gregor Stein, Juergen Koebke, R SobottkeAbstract:Purpose. The relatively new and less-invasive therapeutic alternative “interspinous process decompression device (IPD)” is expected to result in improved symptoms of neurogenic intermittent claudication (NIC) caused by lumbar spinal stenosis. The aim of the study was to analyze IPD position particularly regarding damage originating from surgical implantation. Methods. Anatomic assessments were performed on a fresh human cadaver. For the anatomic examination, the lumbar spine was plastinated after implantation of the IPDs. After radiographic control, serial 4 mm thick sections of the block plastinate were cut in the sagittal (L1–L3) and horizontal (L3–L5) planes. The macroanatomical positioning of the implants was then analyzed. The insertion procedure caused only little injury to osteoLigamentous or muscular structures. The Supraspinous Ligament was completely intact, and the interspinous Ligaments were not torn as was initially presupposed. No osseous changes at the spinal processes were apparent. Contact of the IPD with the spinous processes was visible, so that sufficient biomechanical limitation of the spinal extension seems likely. Conclusions. Minimally invasive IPD implantation with accurate positioning in the anterior portion of the interspinous place is possible without severe surgical trauma.
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The role of the inter-/Supraspinous Ligament complex in stand-alone interspinous process devices: a biomechanical and anatomic study.
Journal of neurological surgery. Part A Central European neurosurgery, 2012Co-Authors: T Kaulhausen, J Siewe, P Eysel, J Knifka, H P Notermans, J Koebke, R SobottkeAbstract:Lumbar spinal stenosis (LSS) with neurogenic intermittent claudication is one of the most common degenerative spinal diseases in the elderly. For patients over 65 years with LSS, open decompression is the most frequent spinal surgery. One problem associated with decompression surgery is the emergence of instability, which is found in varying grades of severity. For some patients with LSS, interspinous process devices (IPD) may be a viable alternative to open decompression. The purpose of this study is to examine the destruction and changes to the interspinous and Supraspinous Ligament complex after percutanous IPD implantation. Biomechanical and anatomic assessments were performed on the lumbar spine (L1-L4) of 11 fresh human cadavers. The biomechanical examination assayed the force necessary to disrupt the interspinous-Supraspinous Ligament complex without and after implantation of an IPD. For the anatomic examination, one lumbar spine was plastinated. Serial 4-mm thick sections were cut in sagittal and horizontal planes. The macroanatomic positioning of the implants was then analysed. Biomechanics: The average age of the cadavers was 80.6±10.2 years. The minimum average disrupting forces measured 313.74±113.44 N without and 239.47±63.64 N after IPD implantation, a significant (p<0.018) decrease of an average 23.7%. Anatomy: After posterolateral percutaneous IPD implantation, the posterior third of the interspinous Ligament, the Supraspinous Ligament, the thoracolumbar fascia and paraspinous muscles bordering the inter-/Supraspinous Ligament complex remained undamaged. The implantation of an interspinous "stand-alone" spacer significantly minimises the force necessary to disrupt the ISL/SSL complex. After posterolateral percutaneous IPD implantation, the thoracolumbar fascia and associated musculature, which act in synergy with the ISL/SSL complex to stabilise the vertebral column, remain intact. © 2012 by Thieme Medical Publishers, Inc.
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The role of the inter-/Supraspinous Ligament complex in stand-alone interspinous process devices: a biomechanical and anatomic study.
Central European Neurosurgery, 2012Co-Authors: T Kaulhausen, J Siewe, P Eysel, J Knifka, H P Notermans, J Koebke, R SobottkeAbstract:Background Lumbar spinal stenosis (LSS) with neurogenic intermittent claudication is one of the most common degenerative spinal diseases in the elderly. For patients over 65 years with LSS, open decompression is the most frequent spinal surgery. One problem associated with decompression surgery is the emergence of instability, which is found in varying grades of severity. For some patients with LSS, interspinous process devices (IPD) may be a viable alternative to open decompression. The purpose of this study is to examine the destruction and changes to the interspinous and Supraspinous Ligament complex after percutanous IPD implantation. Methods Biomechanical and anatomic assessments were performed on the lumbar spine (L1–L4) of 11 fresh human cadavers. The biomechanical examination assayed the force necessary to disrupt the interspinous-Supraspinous Ligament complex without and after implantation of an IPD. For the anatomic examination, one lumbar spine was plastinated. Serial 4-mm thick sections were cut in sagittal and horizontal planes. The macroanatomic positioning of the implants was then analysed. Results Biomechanics: The average age of the cadavers was 80.6±10.2 years. The minimum average disrupting forces measured 313.74±113.44 N without and 239.47±63.64 N after IPD implantation, a significant (p Conclusion The implantation of an interspinous “stand-alone” spacer significantly minimises the force necessary to disrupt the ISL/SSL complex. After posterolateral percutaneous IPD implantation, the thoracolumbar fascia and associated musculature, which act in synergy with the ISL/SSL complex to stabilise the vertebral column, remain intact.