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.

The Dynamic Sitting Exercise (DSE)

Life can be busy. And with this busyness, people often do not have the time for lower back pain exercises. In 2010, Jerome Fryer (the owner and developer of Dynamic Disc Designs Corp.) set out to measure a simple seated decompression strategy for the lumbar spine. A pilot study used an upright MRI to investigate changes in the lumbar spine before and after this Dynamic Sitting Exercise (DSE) 1

It was originally coined “chair-care decompression exercise” to make it memorable. In a recent article written in the Indian Journal of Physiotherapy and Occupational Therapy, the researchers renamed it DSE and compared it to the popular McKenzie prone press-up. 2


Dynamic Sitting Exercise

Dynamic Sitting Exercise (DSE)


McKenzie Prone Press-up

McKenzie Prone Press-up

These researchers recruited thirty adults in the age range of 20-30 years with mechanical low back pain. To read the full inclusion and exclusion criteria, you can visit the full-text link in the references below. They randomly assigned the participants to two groups: the DSE group or the McKenzie prone press-up group. Each subject conducted 6 repetitions within the 5-minute interval with the exercises being conducted at the beginning of the 5 minutes, followed by 4 minutes of rest. Over the course of 30 minutes, each participant would have performed 6 repetitions multiplied by 5 sets for a total of 30 repetitions over the course of 30 minutes. This was equivalent to 2.5 minutes of active exercise over the course of 30 minutes.

Exercise Protocol

Exercise Protocol


The DSE instructions included:

  1. sit upright
  2. place hands-on seat pan
  3. push down on the seat pan to offload the lower spine
  4. participants should feel a slight stretching in the lower back
  5. hold for 5 seconds
  6. return to neutral for 5 seconds
  7. while returning to neutral, draw-in-abdomen.


The McKenzie Prone Press-Up instructions included:

  1. lie down on the abdomen
  2. extend back while on elbows and palms down (neutral position)
  3. perform press-up maneuver with straight arms for 5 seconds
  4. return to neutral for 5 seconds


Over 6 weeks, outcome measures included the Visual Analog Scale for pain and the Short Form-36 Health Survey Questionaire for quality of life.

What did they conclude?

Both forms of exercise demonstrated improvement of pain and quality of life. However, the DSE outperformed the McKenzie Prone Press-up in this group of mechanical low back pain adults.

Overall, this paper could have been written a little better. Their conclusions were bold and overly confident. It is still an important paper to share as the practicality of investing a few seconds of offloading to your work-day while sitting looks to be promising in those with lower back pain in this age range.


lordosis. degenrative joint disease

Flat Back (Lack of Lumbar Lordosis) and Disc Herniation

Lordosis, or the lack of it, has been thought to be a biomechanical precursor to disc herniation in the lumbar spine. To investigate this possible correlation, a group of researchers from Gothenburg University looked at sixteen young active young patients with a median age of 18yrs old who experienced a disc herniation and underwent discectomy surgery. 1

Lordosis is the curve in the lower back—which they measured before and after the surgery.


Researchers used the Roussouly 4-type classification system to measure the degree of lordosis in the lumbar spine.

The researchers found less lordosis in the subjects that had surgery for their disc herniation. In other words, disc herniation was twice as likely to be present in the group with a flatter back. All the disc herniations were found to be in the lowest two levels of the lumbar spine (L4-5 and L5-S1), consistent with other epidemiological studies. 2

Dynamic Disc Designs Models

At Dynamic Disc Designs Corp. we have worked to represent the anatomy accurately. Our Professional LxH  Dynamic Disc Model is created with 12mm of disc height anteriorly and 10mm posteriorly providing a slight lordotic curve. Further, the model has been created with a higher percentage of nucleus pulposus which is often found in younger lumbar spines. To demonstrate that disc herniation occurs more likely with less lordosis all one has to do is dynamically move the single-level model into a less lordosis position and manually create compression. With more lordosis, the nucleus has a more difficult time penetrating through the outer annulus fissure. This can be an important posture teaching point in the prevention of disc herniation.

If you want to take your patient education to a dynamic level, explore what Dynamic Disc Designs models can do for you, your practice and ultimately, your patients.

facet osteoarthritis

Facet osteoarthritis pain is common and thought to be a significant contributor to back pain in the US. Within the United States, it costs 100 Billion dollars annually to combat this endemic problem. However, back pain can originate from many anatomical structures, and the facet joint is only one of them but thought by many as significant. Other common pain structures are the intervertebral discs in the case of disc bulges, disc extrusions, disc protrusions and frank nuclear sequestration. There are also more severe causes of back pain like aneurysm and other organ pathology, so it is crucial to have a professional look carefully at the diagnostics of each case.

In the case of mechanical lower back pain (others use the term non-specific lower back pain), the facet joint garners good attention. The word ‘facet’ comes from the French facette (12c., Old French facete), diminutive of face “face, appearance” and are two anatomical structures that reside behind the intervertebral disc.

Facet osteoarthritis

Modeling facet osteoarthritis is tricky because of the complexity of motion at the spinal level. The intervertebral disc height plays a role with respective facet compression because it resides on the front of the spinal motion segment. It is this compression thought to be contributing to back pain.

Clincally, facet osteoarthritis pain is often unilateral in nature

In a study conducted recently 1, researchers worked to induce facet joint arthritis by creating compression with a spring. Over time the researchers found the increased expression of interleukin‑1β and tumour necrosis factor‑α expression. In other words, with more compression elapsing over time, the more the expression of the molecules related to many low back pain patients.

This is an important study linking the mechanics of compression and the associated physiology of molecules, which are thought to be markers of back pain patients.

At Dynamic Disc Designs, we have developed models to help explain the associated compression of facet joints as it relates to disc height loss and gains. We are committed to bringing the best in modelling. Explore our website for more.

Crack Propagation Osteoarthritis

Osteoarthritis is common and causes much disability in the world to many. It is a joint condition that causes pain, which often leads people to seek therapy. Despite the efforts to learn the underlying causes, researchers have been confused as to the source and propagation of degenerative osteoarthritic changes. We know that surface injury to cartilage can occur from high-risk competitive sports and result in the development of osteoarthritis; the precise reasons as to this has eluded researchers in the field. Understanding the mechanobiology of the early stages of OA when micro-cracks start will be an important piece of the puzzle in the prevention of osteoarthritis.

Just this month, a group of researchers out of the University of Calgary, looked at the finer micro-structure of the cartilage. 1 They looked at crack propagation (micro-fracturing) of the cartilage to get a better understanding of the load and respective magnitude as it relates to the damage. Their objective included looking carefully at the local strain distribution of the cartilage nearby to the microcracks.

What did they do?

Cylindrical osteochondral punch plugs were harvested from pig knees and fixed to a custom design compression testing device. The cartilage thickness was measured at three different locations of the surface. To prevent dehydration, which can often occur in these testing environments and affect the results, they fully immersed the sample in a phosphate-buffered solution. The thickness of the cartilage was measured using light microscopy. Measures of strain were applied. To simulate the crack in the cartilage found in-vivo, vertical cuts were made in the cartilage at the most superficial part of the surface cartilage along with the middle zone.

What did they find out?

Axial strains were significantly more abundant at the damage zone compared to the non-damaged cartilage. This indicates that the ability of the cartilage to resist compression is less in the damaged or micro fractured cartilage, disrupting the biomechanics.

Crack Propagation Osteoarthritis


What can we take away from this study?

The drive to learn about osteoarthritis is essential. Billions of dollars are spent annually for a multitude of therapeutics, including joint replacement, injections, pharmaceuticals and manual therapy. By learning about how cracks propagate in the cartilage and, ultimately, how we prevent the development of osteoarthritis will be a great asset to the planet.

At Dynamic Disc Designs, we work to follow the research and work to bring that to the doctor-patient engagement process. Our latest modelling now includes a crack in the cartilage of the facet joint.



Disc Herniation Spondylolisthesis

Spondylolisthesis is the slippage of one vertebra on another—frequently found with disc herniation. However, in this recent paper titled: “Over-reporting of the disc herniation in lumbar spine MRI scans performed for patients with spondylolisthesis” 1 they sought to find if disc herniation is over-reported and in turn, possibly over-treated.

Spondylolisthesis is best diagnosed when the spine is under load. Many MRI scans, because done in the lie-down position, miss these small (or large) slippages. To accurately assess one for a spondylolisthesis, the spine is best visualized by x-ray in the forward bending and backward bending position. Upright MRI is also another great way to assess; however, the access to these expensive machines may not be available.

The authors of the above paper discuss how it is imperative to find an accurate diagnosis for both the conservative and surgical management of back pain.

Disc herniation is often found with spondylolisthesis. However, what they found was disc herniation reporting was often over-reported and believed that the disc herniation was more of a pseudo disc herniation rather than an actual disc herniation.


What do the authors mean by pseudo-herniation?


The authors point to a nomenclature issue. In Fardon’s 2014 paper 2 he helps clarify the language professionals use when discussing disc herniation, extrusion, protrusion and bulge. However, the authors of this paper explain that Fardon’s article does not address this nomenclature in light of spondylolisthesis.


They point out in this retrospective study of 258 patients that disc herniation was over-reported because the disc herniation was read with the superior vertebra in mind rather than referencing the lower vertebra. In other words, if the radiological reporting used the lower vertebra as a reference point, the reporting of a disc herniation would be much less because the outer disc border remained anterior to the posterior vertebral ring apophysis. Therefore, it is essential to deferentially diagnose whether symptoms are related to a real disc herniation or due to the mechanics of a spondylolisthesis. A spondylolisthesis can throw off the reporting in this case.



Dynamic Disc Designs creates 3d models to help reveal the dynamics of disc herniation, including the up-roofing of the disc material. This mechanism is shown in our Professional LxH Model, with the added features of spondylolisthesis.


Ergonomic Seating

Lower back pain is a global problem. Its rate has increased steadily over the last several decades, with now more than 637 million individuals suffering around the world. 1

What has also been steadily increasing is the act of sitting. People are working from home more than ever, especially with the recent coronavirus outbreak, forcing people to self-isolate to reduce the spread of the disease. Even before COVID-19, businesses and individuals have increasingly adopted computer-based platforms that increase screen time. Engaging with screens are a large part of life for many and presents a new reality of work life.

What do we know about the origins of lower back pain?

Lower back pain is considered multifaceted with intervertebral disc degeneration (IDD) being the most probable leading cause. IDD is a precursor to many commonly known conditions, with only some of them being disc herniation, spondylosis and lumbar spinal stenosis. 2 A common radiological finding within IDD and the other related spinal conditions are the reduction of spacing between the vertebra. Or, in other words, disc height loss. So how does disc height loss occur?


Disc height loss is normal through the day/night cycle. As humans, we lose approximately 20% of the fluid from our discs over the day to regain it at night, when we lie down to sleep. 3 The regaining or recovery of the fluid and respective height is imperative for the health of the disc. If we do not recover the height, this leads to a state of compression and resulting pain. On the flip side, if discs regain too much fluid, this also results in over expansion as we see with astronauts. Problems also incur if one lies in bed for too long.


So we need a balance—a balance of compression and decompression to our spines. If there is an excess in either direction, problems can arise. To minimize over-compression, we have to look at our postural behaviours. And one act that we just do too much of is sitting. We know that sitting causes disc compression and height loss as the spine undergoes the movement of flexion. 4. And why does the spine round into that posture? Well, the main reason is because of traditional seat pans 5 which cause the lumbar spine to round and causing increased pressure on the disc. 6

So what is it about sitting that is so different?

If you look carefully at a single motion segment (vertebra-disc-vertebra complex), each vertebra is separated by three joints. The largest and most important anatomical structure in the fight to resist compression is the intervertebral disc, which supports about 80 percent of the load in the standing posture. The remaining 20% load is distributed through the facet joints. Lumbar Model - Intervertebral Disc and FacetsProfessional LxH Dynamic Disc Model

I often describe this using a tricycle as a metaphor. The big tire on the front is like the disc, and the two facet joints are similarly like the two little tires. Sitting will place all the pressure over the big tire on the front of the tricycle, which increases the pressure on it. And over time, because the disc is a hydraulic structure, water will squeeze water out of it, reducing its height.

Neutral Loading

Office Chairs and Lumbar Alignment

To optimize sitting alignment during sitting, researchers have looked at lumbar supports to balance the motion segments of the spine. 7 These groups of researchers asked one question: Which office chair feature is better at improving spine posture in sitting? What they did was evaluate 28 participants, measuring by x-ray postures in four different chair conditions: control, lumbar support, seat pan tilt and backrest with scapular relief. They concluded that not one of the four stood out with regards to improving lumbar flexion, but the angled seat pan did improve pelvic posture significantly. They also discussed how the tilting seat pan did reduce flexion in the lumbar spine and suggesting that this may still be of practical significance. 8


Ergonomic Seating from Dynamic Disc Designs Corp.

At Dynamic Disc Designs, we are introducing ergonomic seating. Some may know the CEO, Jerome Fryer BSc DC, who has, from an early start in his career, observed the increasing trend of global sitting. In 1998, he made a simple observation during his training years as a chiropractor. And this simple observation of self-decompression led to two publications in The Journal of Bodywork and Movement Therapies and also The Spine Journal.

With the knowledge gained, he thought it was time to bring it to others.

With an adjustable seat pan and a saddle orientation to keep your hips in a more neutral position, the Ergonomic Saddle – Task Chair will optimize lumbopelvic posture. A 12-degree seat pan tilt is adjustable to each user’s unique lower back.

Seat Pan Angle Adjustability

Adjustable Tilt






Telehealth in light of COVID19

The current focus of health systems on hospital preparedness and public health measures to reduce spread of the COVID-19 virus, and flatten critical illness curves, has led to the reduction, or temporary closure, of many in-person clinical services around the world.  Despite the importance of readiness for spikes in critical illness related to COVID-19, as well as for maintaining physical distance to curb spread of disease, it is also crucial to keep in mind that many patients are currently at risk for experiencing gaps in care, as services deemed non-urgent have been put on hold.  Health care providers are finding that telemedicine may present a possible solution to the issue of continuity of care while maintaining physical distance during the COVID-19 pandemic restrictions.

What is Telemedicine?

The World Health Organization defines telemedicine as “The delivery of health care services, where distance is a critical factor, by all health care professionals using information and communication technologies for the exchange of valid information for diagnosis, treatment and prevention of disease and injuries, research and evaluation, and for the continuing education of health care providers, all in the interests of advancing the health of individuals and their communities.”1  As this definition suggests, there are many potential contexts for leveraging telemedicine technologies and approaches – as well, there is a growing body of literature to support and inform the use of telemedicine in practice.

Telemedicine is currently demonstrating utility in an environment where it is necessary to maintain distance while providing optimal patient care.2,3  Lock downs or quarantines due to COVID-19 have pressed the need to move the delivery of certain health care services onto a telemedicine platform for a number of patient scenarios.  One of these is to facilitate ongoing dialogue between patients and their health care providers regarding existing and/or chronic health conditions.4 A crucial part of this dialogue is clear, sound and effective patient education.

Patient education on a telemedicine platform – to support the initiation of treatment regimens, follow-up and/or self-care at home – can be carried out in accordance to evidence-based findings for effective in-person patient education practice. One such finding is the utility of demonstrations and visual aids in order to elucidate to patients their pathology and reasons for their symptoms, and in order to explain why and how certain treatment or self-care regimens/behaviours will be effective.5,6  In the case of patient care related to spinal and musculoskeletal conditions, this could include the use of spine and intravertebral disc models.

How Spine Models by Dynamic Disc Designs could help

Spine models by Dynamic Disc Designs are anatomically accurate with features that can easily and clearly be pointed out to patients during their education sessions with their health care provider.  This is especially useful when utilizing a telemedicine platform, where the patient may need extra support to feel connected to the health care provider’s message.

Jordan van der Westhuizen is a Managing Partner and an Occupational Therapist (Hons) at Enhanced Occupational Therapy in Perth Australia.  He utilizes Dynamic Disc Designs spine models in his patient education sessions, both in-person and via telemedicine.  He notes,  “…Not only for in-person consultations but now for telehealth, our spine model allows the patient to understand their back issues and mechanisms causing pain which is a key component in the patient’s health journey.”

Telehealth - Spine Education

Dr. Robert Peace is a chiropractor in Tulsa Oklahoma who also currently utilizes Dynamic Disc Designs models for patient education sessions via telemedicine.

“The ddd spine models are an invaluable resource for the relating of findings and communicating the many causes of spine pain. The patients always seem to get a better understanding of their condition when viewing the detailed anatomy on this model.  I’m looking forward to receiving my next model – the Medial Branch Dynamic Disc Model – to even better demonstrate and educate the patients in regards to facet joint inflammation and medial branch involvement.”

We are currently experiencing a global health environment that calls for innovation in patient care on many levels. Health care provided through telemedicine offers opportunities for health care providers to safely and quickly triage patients with symptoms that may be related to COVID-19, but also provides a platform for continuity of care for patients with other illnesses, particularly those that are chronic and thus require ongoing, long-term follow-up.   The use of visual aids such as spine and disc models for patients with spinal issues can enhance the patient education that is an integral component of optimal care for patients with chronic conditions



  • World Health Organization. (1998, December 11-16). A health telematics policy in support of WHO’s health-for-all strategy for global health development: report of the WHO group consultation on health telematics. Geneva. Geneva.
  • Xiaoyun Zhou, Xiaoyun Zhou, Centaine L. Snoswell, Louise E. Harding, Matthew Bambling, Sisira Edirippulige, Xuejun Bai, and Anthony C. Smith. (2020, March 23). The Role of Telehealth in Reducing the Mental Health Burden from COVID-19. Telemedicine and e-health, 26(4).
  • Judd E. Hollander, M.D., and Brendan G. Carr, M.D. (2020, March 11). Virtually Perfect? Telemedicine for Covid-19. New England Journal of Medicine[online]. DOI: 10.1056/NEJMp2003539
  • Vivek Chauhan, Sagar Galwankar, Bonnie Arquilla, Manish Garg, Salvatore Di Somma, Ayman El-Menyar, Vimal Krishnan, Joel Gerber, Reuben Holland, Stanislaw P Stawicki.(2020) Novel coronavirus (COVID-19): Leveraging telemedicine to optimize care while minimizing exposures and viral transmission. Emerg Trauma Shock[serial online], 13(1), pp.20-24.;year=2020;volume=13;issue=1;spage=20;epage=24;aulast=Chauhan
  • Audrey Jusko Friedman, Roxanne Cosby, Susan Boyko, Jane Hatton-Bauer & Gale Turnbull. (2010, December 16). Effective Teaching Strategies and Methods of Delivery for Patient Education: A Systematic Review and Practice Guideline Recommendations. Journal of Cancer Education volume 26, pp12-21.
  • Robert P. Riemsma Erik Taal  John R. Kirwan  Johannes J. Rasker. (2004, December 8). Systematic review of rheumatoid Arthritis patient education. Arthritis care & Research, 51(6), 1045-1059.