News for Dynamic Disc Designs which includes updated research and a synthesis of the most updated studies to help efficiently engage with patients and their back and neck pain.

We take an approach that an evidence-based practitioner would take. Carefully dissecting the history of a patients complaints, weaving the mechanical and psychosocial factors and then deliver a rational and tangible approach to relieving the back pain to the patient. Our news helps keep the practitioner abreast of the latest publications related to musculoskeletal health.

At our headquarters, we dedicate weekly hours to comb through the research for those who treat back pain and neck pain and deliver it.

lumbar disc herniation

A study investigating kinematic changes in subjects with lumbar disc herniation (LDH) performing five activities of active daily living (ADL) found that LDH patients were more apt than healthy subjects to restrict the lower lumbar (LLx) and upper lumbar (ULx) spinal motions when performing ADLs. The LDH patients used pelvic rotation to compensate for their reduced lumbar flexibility and increased pelvic tilt and lower extremity flexion during problematic ADLs. 

What’s at Stake?

Lower back pain affects up to 85 percent of the worldwide population—especially those over 40—and can contribute to musculoskeletal problems when the lower spine and its surrounding structure is overloaded. Because LBP patients often restrict musculoskeletal motions during ADLs to avoid pain, understanding the kinematic idiosyncrasies of LBP patients during their ADLs is essential when treating spinal issues through physical therapy that involves gait and functional training. 

Past research has indicated LBP patients had less transverse plane movement than healthy subjects during level walking exercises. One study found that LBP subjects were more likely to exhibit spinal or pelvic rotation, while another study came to the opposite conclusion but found that LBP patients had less range of motion (ROM) in the lumbar spine than the control group. Conflicting studies have concluded that LBP patients had significant reductions in the range of hip flexion and spinal movement across all three planes during trunk flexion or better ROM in the lumbar spine, with more restriction in the pelvic or thorax ROM. The divergent conclusions are likely due to the trunk and whole lumbar being considered a single, rigid segment, rather than interconnected segments that operate independently. The prior studies may also have neglected to consider the kinematic differences among LBP patient subgroups. Analyzing the variability of joints and segments is vital when studying LBP patients and their unique kinematics. 

This study focused on how lumbar disc herniation (LDH) specifically contributes to LBP, including the lower trunk, thorax, hip, and pelvis. The goal of the study was to use a computing model to study LBP patients with LDH and understand their pain-related modulation of their lower extremities and multi-segmental trunk kinematics during level walking, stair climbing, trunk flexion, ipsilateral pickup, and contralateral pickup. 

The Study

Twenty-six healthy males with a mean age of approximately 24 years and seven LHD diagnosed male patients who were, on average, approximately 28 years old participated in the study. The disc herniations occurred at L4/5 in three of the LDH patients, L5/S1 in three cases, and at both locations in one patient. 

The motion of thorax, ULx, LLx, pelvis, hip, and knee were tracked via 3D active markers placed in various locations on the subjects’ spines, pelvises, thighs, and shanks. All the markers were placed by a single surgeon, who had previously demonstrated the five ADLs the subjects were to perform. After practicing the motions a few times, the subjects repeated them while data was collected through the active markers. 

The kinematics of the thoracic segment, ULx, LLx, pelvis, hip, and knee were calculated using a modified Gait-full-body computing model that would analyze the motion of each lumbar vertebra using at least three markers. The kinematic spine and hip angles were analyzed with the computing model using a Euler rotation sequence of spinal segments or thigh/pelvis movement, and the thoracic segment as it related to the L1 vertebra. The ROM for all segmental or joint angles during flexion-extension or gait cycles across all three planes in three planes was calculated, and data analysis was performed using a custom program. 

Results

The LDH subjects had much more pelvic rotation and LLx rotation than the healthy subjects during level walking. The LDH group had much less ROM for thoracic flexion, pelvic tilt, and hip abduction during stair climbing, but they showed more ROM for LLx rotation. No clinically significant variance was noted between the two groups for thoracic flexion, trunk flexion or ipsilateral and contralateral pickups. Lumbar flexion ROM was significantly decreased in the LDH group—especially for ULx with nearly no sagittal angular displacement.  

The findings suggest that people with LDH modulate their movement patterns and motor regulation in response to, or avoidance of pain. There were evident kinematic differences between the healthy subjects and LDH patients in this study. LDH patients had more pelvic rotation and increased LLx rotation during level walking, contradicting earlier studies where patients had less than or similar pelvic rotation when compared with healthy subjects. The use of different marker sets, study methods, computer models, and speed of motion might account for the varying test results, but it appears that pelvis and LLx motions in the transverse plane may have a more pronounced effect than that of the other two planes during LDH abnormal motion level walking analysis. 

Conclusion

In regard to the direction or range of motion, there were contrasting kinematic characteristics and different adaptations to LDH between the ULx and LLx in this study. The thoracic motion did not appear to be affected by the LDH when subjects were performing the ADLs, with the exception of stair climbing. During all five ADLs the LDH patients maintained limited lumbar flexion, and their pelvises, knees, and hips compensated for the lost lumbar motion capacity in the sagittal plane during contralateral pickups. In four of the five ADLs (the exception being stair climbing), the LDH patients increased their pelvic rotation significantly. They also had higher rates of antiphase movement between thorax and pelvis in the two pickups and in level walking and stair climbing in the transverse plane between ULx and LLx.

The findings of this study should help provide a more comprehensive understanding of how LDH influences kinematics and lead to more specific treatments and better therapeutic outcomes for LDH patients. 

disc height

In this Spine Education video, Dynamic Disc Designs’ Dr. Jerome Fryer demonstrates the benefits of helping lower back pain patients better understand their condition by using dynamic models and visual aids.

“How often do you encounter a patient that explains that their symptoms are worse as the day progresses?” he asks.

Though clinicians understand the key to a graduating pain syndrome involves a complex biomechanical and biochemical matrix in the spine, back pain patients don’t need extensive medical knowledge to appreciate the dynamics of what is happening in their bodies. A simple visual aid can help clarify and simplify their predicament and potential solutions.

 

Hands-On Demo of Diurnal Expression of Fluid from the Disc

Using a dynamic disc model, Fryer demonstrates the diurnal expression of fluid from the disc as the disc height changes over the course of the day.

“We know that the disc height is tallest in the morning,” he says, holding a fully expanded disc model to the camera and then slowly squeezing the dynamic model to demonstrate the loss of height that occurs throughout the day.

“As the day progresses, the disc height will slowly lose its height [causing the facets] to imbricate or shingle. If a patient [complains] their symptoms are more present as the day progresses, you [use] this graph 1 to demonstrate what’s happening in their spine.

“As the person gets up in the morning, there is a quick change in the disc height in the first 10 minutes,” he says, pointing out a steep curve on the graph.

“As the day progresses, the disc height is lost.”

Annular Disruption in Degenerated Discs Reduce Capacity to Maintain Height

Fryer says the situation can be even more extreme when a patient is suffering from degeneration in the disc because the disc can no longer hold its full height, due to disruption in the annulus.

“Helping patients understand symptoms as the day progresses will help them understand why it hurts,” he says. “That gives you more empowered strategies to help patients get motivated, if its posture, or even recumbency, or exercise, or getting out of a chair to help with the disc height changes. These dynamic disc models are very powerful in helping patients with self-awareness.”

For more information on dynamic disc models and patient teaching aids, visit Dynamic Disc Designs.

Zygapophyseal Joint Pain in Chronic Whiplash Patients

A study 1 of sensory hypersensitivity in patients suffering from chronic whiplash associated disorder 6 months or more after being involved in a motor vehicle collision (MVC) found that the hypersensitivity was reduced, and pain thresholds were increased after receiving a medial branch block (MBB) procedure of the cervical spine.  The results of the study indicate the cervical zygapophyseal joints most likely contribute to sensory hypersensitivity caused by peripheral and centrally mediated pain.

 

What’s at Stake?

A common problem of people who have been involved in MVC’s is chronic whiplash associated disorder (WAD). According to research, between 32-56 percent of those involved in MVC’s may continue to suffer from related disability or pain 6 months or longer after their accident. Research has implicated the cervical zygapophyseal joint as a possible source of chronic hypersensitivity in 54-60 percent of subjects with WAD—evidence that is supported across multiple biomechanical and neurophysiological studies. It is thought that tissues that had been seemingly unaffected by the MVC experience sensory hypersensitivity when the body’s pain processing mechanisms are altered in the spinal cord. This sensory hypersensitivity and central nervous system hyperexcitability decrease the pain thresholds in the body, creating an exaggerated response for thermal, electrical, or mechanical stimuli for WAD patients. The prognosis for WAD patients suffering from sensory hypersensitivity is poor, and better understanding of the phenomenon could improve long-term treatment outcomes.

The Study

 

The pretest-posttest exploratory study involved 18 volunteers (15 females, 3 males) with an average age of 45 years and who had experienced WAD for 6 months or longer, with numerous neck complaints, body tenderness, and decreased range of motion. A control group of 18 healthy patients (15 females, 3 males) with an average age of 45 years also participated in the study. A group of chronic WAD patients with pain reported for 6 months or longer and who had a minimum of 80 percent decrease in neck pain intensity following an intra-articular zygapophyseal joint block procedure also took part in this study. Exclusionary criteria included pregnancy, previous history of headaches or neck pain requiring treatment, central or peripheral neurological problems, coronary artery or peripheral vascular disease.

Researchers rated the subjects’ pain intensity levels on a scale of 1-10 before and after receiving MBB procedures. Quantitative sensory testing (QST) based upon pressure pain thresholds (PPT’s) and cold pain thresholds (CPT’s) were conducted on the control and WAD groups. All measures were recorded, including patient demographic variables and their current MVC litigation status.

Cold Pain Threshold Testing

A 30mm x 30mm thermode set to 32 degrees Celsius placed over the anaesthetized articular pillars of the cervical zygapophyseal joints measured cold pain thresholds in the test subjects as the temperature was decreased at the rate of 1 degree Celsius per second. Patients used a self-controlled switch to indicate when the sensation of cold turned to pain as each bilateral site was tested. (The minimum temperature was 1 degree Celsius.) The average values were gathered for analysis.

Pressure Pain Threshold Testing

The articular pillars of the cervical zygapophyseal joints, peripheral nerve trunk of the median nerve, and the tibialis anterior were measured in the PPT tests, with the subjects using a self-controlled switch to indicate when the sensation of pressure turned to one of pain. The tests were performed three times bilaterally on each site, with a pause of 10 seconds between each test. The average values were recorded and later statistically analyzed.

Cervical spine model to demonstrate zygapophyseal joints

Dynamic Cervical Model

Diagnostic Cervical Zygapophyseal Joint Blockade

The patient group with chronic WAD underwent two diagnostic zygapophyseal joint block procedures—one, prior to the study, where a spinal needle was inserted with fluoroscopic guidance into the joint while the patient was in the prone position. An injection containing a local anesthetic and a corticosteroid was made into the affected zygapophyseal joint. If these patients experienced a relief of pain intensity of at least 80 percent but their pain later returned, they received the second MBB injection. In this study, none of the patients were excluded from the second MBB, as each of them had experienced at least an 80 percent reduction of pain from the first procedure, with the return of pain post-procedure.

Results

The WAD patients demonstrated clinically significant changes in their sensory hyperactivity measurements after the blockade of the cervical zygapophyseal joint. These changes included a decrease in CPT’s and increase of PPT’s in the cervical spine and distal sites. This finding is unique in the study of chronic WAD patients and suggests that minimizing the source of pain—in this case, the zygapophyseal joint—may help modulate sensory hypersensitivity in chronic WAD patients, at least in the short-term. The study authors urge larger trials with long-term follow-ups of patients to gather more information and improve the treatment outcomes of patients with WAD.

intradiscal, endplate

A study 1 on the efficacy of intradiscal biologic therapy, where new cells or genes are implanted into the degenerated disc matrix to reduce inflammation and increase matrix cell production, found that degenerated discs may not have the necessary nutrient transport capabilities to ensure proper disc nutrition during this form of therapy. The authors of the study emphasize the importance of research into the determining factors influencing disc cell nutrient transport in informing targeted treatments and strategies to improve disc nutrition in degenerated discs.

What’s at Stake?

Disc degeneration (DD) is a chronic condition that causes spinal pain in aging adults worldwide. The process of DD involves biomechanical modeling of the entire disc matrix and frequently leads to surgical intervention to remove the offending disc and restore functionality to the spine. For many patients, surgical procedures are unsuccessful, however. A noninvasive treatment that has demonstrated recent promise involves regenerating the DD by injecting it with genes, growth factors, small molecules, or implanted cells. These procedures are intended to reduce inflammation and catabolism and assist in the creation of a new disc matrix. But a cell-rich disc requires increased nutrients, and the cartilage endplate (CEP) of the DD may not have the capacity to deliver these nutrients to the matrix. In this study, researchers examined the effects of CEP transport properties in DD on nutrient diffusion and cell function and survival.

The Study

In order to isolate the variable of how nutrient supply affects the nucleus pulposus (NP) cell function, the researchers involved in this study mimicked the in vivo, diffusion-poor disc environment by creating diffusion chambers with similar parameters to isolate the NP nutrient supply mechanics. The cells of the NP receive nutrients that are diffused through the CEP matrix. Cells at the center of the lumbar discs can be up to 10mm from a capillary, while other cells can be just beside a CEP.

Researchers provided glucose and oxygen to cultured NP cells within the chambers. These nutrients were delivered through diffusion from human CEP’s from the open sides of the chamber. Metabolites were expelled into the culture medium by CEP diffusion. The functioning and survival of the cells require a balance between CEP transport properties and cell density, allowing for the request and supply of nutrients. The researchers reproduced the disc matrix environment and physiologic transport conditions in their CEP tissue cultures and diffusion chambers to monitor the effects of NP cell viability and gene expression across the different conditions of nutrient transport.

Specifically, intact human CEP’s from human cadaveric lumbar spines were used for the study. Full-thickness samples of the CEP’s and surrounding calcified cartilage were frozen and sectioned. The researchers calculated the diffusivity of each full-thickness CEP sample through fluorescence and photo-bleaching and using the Axelrod method. They measured each CEP’s biochemical composition spatially via imaging. They created special maps of the collagen, aggrecan, and mineral-to-matrix ratio of the CEP samples with the highest and lowest diffusivities. They measured CEP thickness with photomicrographs and then determined the average measurement across the five chambers.

Bovine NP cells were used in the study (similar to human NP cells). Post-incubation cell viability was determined using a cytotoxicity assay involving gel-stains and low-magnification imagery. Each L4-L5 donor CEP was analyzed for cell density and the anabolic and catabolic gene expressions were examined after chamber incubation. A regression model of fluorescence intensity was used to determine the NP cell gene expression and distance from the CEP. Spatial fluctuations of the CEP composition were described based upon regression models.

Results

The diffusive transport of nutrients varied widely between the CEP samples, affecting the function, health, and survival potential of the NP cells. In fact, there was a four-fold variation in small solute diffusivity in our human CEP sample array. Those allowing less diffusive transport reduced the supply of nutrients to the NP and shortened the viable distance within the diffusion chambers up to 51 percent with typical cell density. Those permitting poor diffusion seemed to downregulate anabolic and catabolic NP cell gene expression. This may mean that a reduced number of disc cells are capable of being sustained through low nutrient CEP diffusion, and the cell’s ability to retain its matrix homeostatic condition is hindered.

When we increased cell density, there was a reduction in cell viability caused by the CEP transport properties, though increasing cell density should raise nutritional demands and shorten the viable distance.  The CEP’s in our study that exhibited low diffusive transport were unresponsive to doubling the cell density, perhaps because they did not provide enough nutrient diffusion to nurture the cell.

We imaged the CEP’s to identify any differences between those with low or high intradiscal diffusivity. Our data found that those with low-diffusivity (and shortened viable distance) contained more collagen and aggrecan, mineral, and lower cross-link maturity. This could explain the blockage of solute penetration and diffusion. At any rate, there appears to be a strong correlation between NP cell survival or function and the availability and mobility of the nutrient supply in the CEP. Compositional defects with the CEP matrix can inhibit nutrient diffusion and undermine biologic therapies that depend upon an increased supply of nutrients to the cell matrix to succeed.

Summary

Our findings suggest that the composition of CEP can contribute to or detract from the function and viability of NP cells. Deficits within the CEP matrix can cause poor nutrient diffusion and block solute passages. This can cause an abundance of collagen and aggrecan, as well as mineral, and lower cross-link maturity. When cell density is increased, CEP’s developed transport deficits, decreasing the cell’s viability. It appears NP function and survival are dependent on the proper CEP composition, as an imbalance in this makeup can reduce the supply of nutrients to the cells, reducing the success rates of biologic therapies.

 

intensive patient education, pathoanatomy

This study 1 published in JAMA (Neurology), randomly selected 202 acute low back pain patients to compare pain education to non-pain education. The results demonstrated not much difference between the groups.

The Methods

Participants engaged with their common physician and in addition to this familiar interaction, each participant was then randomly partitioned into two groups. Each of these groups experienced, in addition to the advice and interaction of their physician, an additional two x hour sessions of either:

Group 1: Normal engagement with doctor PLUS intensive one on one patient education (delivered by clinical psychologist in pain management (M.K.N.) trained) for an additional 2 (1hr) sessions. This patient education was delivered based on Butler’s and Moseley’s work. 2

Group 2: Normal engagement with doctor PLUS placebo patient education (delivered by the same clinical psychologist) for an additional 2 (1hr) sessions. Participants in the placebo patient education group received no information, advice, or education about low back pain from the trial clinician. Participants were encouraged to talk about any topic that they desired.

The Results

Retention rates remained high for both groups at ninety percent. Intensive patient education was not more effective than placebo patient education at reducing pain intensity at the three months. There was a small effect of utilizing intensive at one week and at three months but not at six or twelve months.

 

Discussion

In this study, patient education was used through a psychological framework model rather than a biomechanical model. It is important to understand that this study does not mean that patient education is ineffective or as effective as a placebo. This patient education angle does not attempt to help patients understand the cause of their pain. This approach is more of a top-down psychological strategy of patient education. Methods to subclassify these acute low back pain patients into specific biomechanical categories and then, offer those patients specific education and movement strategies would be helpful to study as groups within the acute low back pain group. These sub-groups could then be compared to placebo.

 


At Dynamic Disc Designs, we believe that empowering patients with a greater sense of self-awareness on the probable mechanical cause of the acute low back pain can be helpful in the management. Initially, pain-reducing strategies through movement awareness of painful structures should be prompt and focus on reducing nociceptive inflammation for the patient. Following the acute phase of low back pain, professionals using our dynamic disc models can further promote the physical awareness of specific postures to help prevent the recurrence and avoid a progression of the condition. Our models allow the practitioner to explain patho-anatomy in a patient-friendly way that does not induce fear avoidance behaviours for the long term.  They also enable the practitioner to provide a realistic forecast of the temporal biological adaptation process within the degenerative cascade framework of natural ageing with a dynamic 3d model. In other words, our dynamic disc models assist the patient engagement process with the opportunity to bring up anatomy in a non-scary and empowering way. We look forward to more research on this topic.

 

 

3d modeling, endplate lesion

An October 2018 study compared MRI’s of 966 lower back pain (LBP) patients to introduce a simplified, reliable method of classification for common endplate lesions. The study also noted associations between endplate lesions and variables, including age, rate of disc degeneration, sex, and Modic changes. The researchers then demonstrated the new system’s reliability by repeated observational rating over a period of days, using outside raters evaluating a percentage of the total sample results. The demographic and physiological findings of the study were largely in agreement with previous IVD endplate lesion studies but also added novel findings that had not previously been published.

basivertebral nerve, bone marrow edema, modic changes

Modic vertebra model- midsagittal cut exposing the basivertebral nerve.

The Study

The subjects in the study were all LBP sufferers under the age of 70, excluding patients with a history of back surgery, spondylodiscitis, or vertebral fractures. Data including age and sex were collected on all patients, and images were scanned and evaluated by an experienced radiologist.

A scoring and classification system for the Lumbar IVD spaces was noted on the images, with the descriptions:

  • Normal—Physiological curvature of both endplates, without the detection of any visual lesions in any of the sagittal MRI IVD space slices.
  • Wavy/Irregular—Curvature in at least one of the endplates, without detectable IVD lesions.
  • Notched—The presence of at least one circular small or V-shaped lesion on an MRI saggital slice.
  • Schmort’s Node—Clearly evident vertebral endplate deep focal defect, where the endplate is rounded, with a smooth margin
  • Fracture—Thickened bone fragment at the edge of an endplate, or any evident fracture of the endplate with similarly-sized fragments

A sampling of the image data was also evaluated multiple times over a period of two days by independent raters to ensure observer reliability. To determine how often each type of endplate lesion appeared associated with disc degeneration and alterations of the MRI signals, subgroups of the study subjects were created, and comparisons were made based on age and sex. A scatter-plot chart was created to track Modic changes, and the relative percentages were calculated and identified against an established threshold.

 

Results

The findings indicated minimal association between patient age at the time of the scan and disc degeneration, as well as minimal Modic changes in older patients, as opposed to entire population studied. The most common types of endplate lesion observed were the “notched” and “Schmorl’s Node” type lesions, and both were more common in male patients than in females. Few of the patients studied had “Wavy/irregular” or “fracture” lesions, which occurred in nearly equal numbers of male and female subjects.

There was a strongly evident correlation between disc degeneration and endplate defects across all LBP subjects in the study. All lesion types increased in all IVD levels where disc degeneration was evident. There was a significant increase in “wavy/irregular” endplate types whenever severe disc degeneration was present. This can be considered a reliable marker for the process of extreme disc degeneration.

Signal alterations were found to be associated with endplate lesions, specifically in “notched,” “wavy/irregular,” and “Schmorl’s Node” endplates. There were nearly twice as many notches in Modic changes of types 1 or 2 corner signal alterations. Schmorl’s nodes showed even more evidence of association.

 

Discussion

Though this study was conducted with the intention of developing a reliable method of endplate defect classification in LBP patients and to find correlations in the distribution of LBP by analyzing a large population of subjects via MRI, previous studies have indicated a correlation between back pain and lesions—something this study did not specifically address.

The results of this study agreed with previous studies that indicated male LBP patients are more likely to have IVD lesions than female patients, though similar lesion-levels were observed in male and female patients who showed evidence of severe disc degeneration, as is found in Schmorl’s nodes and in those with disc fractures.

Most of the patients showed no evidence of endplate lesions on the lumbar MRIs. Of those who who did have lesions, most (18.7 %) experienced them only in a single IVD level, and males were more likely than females (20.7 % to 16.7 %) to show evidence of lesions. Progressively fewer subjects had lesions involving more IVD levels.

There was a very slight correlation between age and lesions in this and some previous studies. That correlation appears to be stronger in the female LBP population than in males—a new observation that has not been discussed in previous studies.

The association between endplate defects and disc degeneration was evident, especially where “wavy/irregular” endplates occurred, indicating severe degeneration of the discs. Signal alterations and endplate lesions also showed a positive correlation, specifically in “wavy/irregular,” “notched,” endplates. This association was significantly evident in Schmorl’s nodes.

 

Lower back pain (LBP) patients present with a wide variety of motor control adaptations in response to, and in anticipation of pain. Though these adaptations manifest across a spectrum of functionality, studies have indicated two common phenotypes that represent the trunk posture and movement of most LBP patients. Further study 1 of these two phenotypes can help practitioners target more specific, effective treatments for their patients who have developed motor control adaptations that may undermine and contribute to their long-term spinal health.

 

Variations of Motor Control Adaptations in LBP Patients

People with LBP adapt the way they move to mediate pain or avoid pain. These adaptations may be conscious or unconscious processes, or a combination of the two, but the changes in posture and movement—what we refer to as “motor control”—involve the muscles, joints, nerves, senses, and integrative processes. Studies of how LBP affects posture and motor control have been inconsistent in the conclusions, perhaps because of the built-in redundancy and flexibility of the musculoskeletal system.

There are many ways to adapt posture and movement in response to pain or in anticipation and avoidance of pain. But because each adaptation creates not only short-term solutions, but potential long-term changes in biomechanics, which can become problematic, creating a cycle of disfunction, it is helpful to study the two most prominent phenotypes of motor function adaptions to create targeted treatment and information options for LBP patients presenting these adaptations.

Identified Motor Function Phenotypes

Tight Control: Some LBP patients exhibit increased excitability and accompanying tight control over their trunk movements, which increases reflex gains, attention to how they control movement, tissue loading, and muscle contraction. While having tight control over trunk movements can help the LBP sufferer from short-term injury by constraining movement, it may also contribute to trunk stiffness and increase the amount of force necessary to move. This may manifest in subtle ways or, in extreme cases, lead to a complete bracing of the trunk, making movement difficult and leading to fatigue.

Patients with extreme tight control over their motor control have been shown to experience a reduction in lumbar stiffness and pain after spinal manipulation. This could mean that the adaptation could, itself, be responsible for pain. These patients are also more likely to experience spinal compression due to increased loading. This compression may lead to a reduced fluid flow in the discs, which may contribute to degeneration over time.

Tight control creates low-level muscular activity, even when the spine is at rest. This can create muscle fatigue, pain, and discomfort. The lack of muscle variability and reduced movement associated with tight control of motor function may also compromise tissue health and compromise the load-sharing capabilities, balance, and movement task learning abilities inherent in the body’s structures.

Loose Control: At the opposite end of the spectrum are patients with loose muscle and posture control and less muscular excitability. This creates an increase in spinal movements and subsequent tissue loading. This may help prevent the short-term pain associated with muscle movement, but the spine is unstable and requires musculature to support movement. Less muscle control means potential failure of the mid-range lumbar vertebral alignment segments, which can cause tissue strain and pain. Spinal displacement due to loose control may cause LBP.

 

Clinical Implications for Loose or Tight Muscle and Posture Control in LBP

Understanding whether a LBP patient is exhibiting a loose or tight control muscle and posture adaptation in response to their pain can help practitioners tailor their treatment in a targeted and more beneficial way. Increasing movement and reducing excitability in later stages of LBP adaptive tight control models can help a patient integrate movement variation as their LBP improves. Likewise, exercises and therapies to help loose control patient models develop more control of their musculature and posture may help them avoid the potential long-term consequences of a proper lack of spinal support.

Assessing LBP patients carefully to identify their motor control phenotype prior to the onset of treatment may allow practitioners to more efficiently target and proactively treat potential complications of their particular adaptation due to actual or anticipated pain.

KEYWORD LONG TAIL PHRASES: motor control phenotyping may help target treatment for lower back pain patients, motor control adaptations in response to, and in anticipation of pain, common phenotypes that represent the trunk posture and movement of most LBP patients, two most prominent phenotypes of motor function adaptions, reduction in lumbar stiffness and pain after spinal manipulation.