Patient engagement is at the core of a patient-centered approach to spine care. Spine professionals engage with their patients with different tools. We all use language but to enhance it, very often a physical model can support the words chosen to educate.

In the past, models have been static, so it made it very difficult to connect patient’s back and neck pain to the specific movements that cause the pain. At Dynamic Disc Designs, we have developed models to help the practitioner engage in a mechanical way through a better rendering of a motion segment. We have created a dynamic disc with the ability of the models to bulge or herniate. We have integrated a dynamic nucleus pulposus and a stiffer annulus fibrosus as well as added features of the ligamentum flavum to show how the facets are inter-related to one another.

Explore how a dynamic model can enhance the language one uses in a clinical setting of a musculoskeletal practice.

A professional lumbar spine model with a flexible and totally dynamic herniating (or prolapse) nucleus pulposus.

Lumbar disc herniation is a very common condition which often generates pain and disability. It is a physiological process that starts from the inside out as the nucleus pushes radially into the annulus fibrosus. But not all disc herniations cause pain, and many of them don’t cause long-term disability.

The literature has been quite varied in answering questions surrounding resorption rate. Yes, many disc herniations resorb, and it is believed to be due to the anaerobic and avascular nature of the nucleus pulposus. Once the material extends beyond the annular outskirts, the immune system identifies it as foreign and macrophages begin to chew it up.

But not all lumbar disc herniations are equal while some respond to manual therapy and some do not. Some cases require surgery to remove the offending material.

In a recent meta-analysis titled: ‘Incidence of spontaneous resorption of lumbar disc herniation’ 1 a group of authors looked at 11 cohort studies but found only a very limited number of high-quality papers on the subject. What they found was the phenomenon of lumbar disc herniation resorption to be 66.66% and suggested that conservative treatment may be a first line approach to reduce costs associated with unnecessary surgical bills.

Disc herniations are quite varied in nature, and this is likely why there is such variability in the outcomes reported regarding resorption and pain. As a spine modeling company which continuously invests in the property characteristics of materials, we have found that subtle changes to the nucleus pulposus make-up and annulus fibrosus tensile properties have a significant impact on the biomechanical behaviour of our lumbar disc herniation model.

Many mechanically anatomical variations exist which can cause a wide spread of varying symptoms. These symptoms are likely related to the type of herniations with some more central within the spinal canal and others are more lateral. Further to that, Depending on the severity, an astute clinician can be relatively accurate in the anatomical location to help in the mechanical management of lumbar disc herniation.

flexion, lumbar, model, pain, relief

Flexion lumbar loading

To see how a spine surgeon uses the model to explain a lumbar disc herniation while referencing an MRI, we present Iona Collins of fixmyspine below.


spine patient education, patient education, spine, models, lumbar, cervical

Improving compliance through spine patient education.

Communication is very important. We all know that. In any relationship, communication seems to be the key element in making sure a common goal is delivered. This is especially important when doctors connect with patients about spinal problems. Spine patient education is imperative in a patient centered model. It also seems helpful in reducing fear avoidance behaviours. 1

Spine Patient Education, Patient Centered, Education

Patient Centered

Doctor-patient communication is critical when relaying information about what the spinal diagnosis is.  Effective communication is also important when relaying the best options for treatment. Doctors and therapists will use their skills to connect with patients. Making reference to the experience they have had with the condition with some offering of favourable outcomes.

What is important is that the patient feels ‘listened to’ and that the doctor can relate their symptoms with the spinal movements that seem to aggravate or miminize the problem.

For example, if a patient exhibits pain bending forward, it can be very helpful to have a dynamic spine model that bulges under flexion load. If a patient can physically see and understand that bending forward can compress the discs (or squeeze on the nerves), this can be very effective in communicating the disc is the likely culprit in the case of sciatica.

spine, education, patient, doctor

Bending forward can cause pain.

Conversely, if a patient demonstrates pain while bending backwards, a dynamic model can show how the facets rub together into extension.

A doctor unequipped for spine patient education is like a mechanic without its tools. Patients are usually very curious about the internal workings of their own bodies. When a doctor or therapist can clearly demonstrate where and why it hurts, often they will be a patient for life.

Spinal pain frequently relates to the spacing of the vertebrae, or lack thereof. Dynamic disc height loss, for example, can now be shown with a model both a doctor and patient can hold and manipulate.


Published May 5th, 2o16 in the New England Journal of Medicine 1 is a review paper on herniated lumbar disk. Dr. Deyo opens the manuscript with a case presentation of  41-yr-old man. He develops progressive increasing lower back and leg pain from doing yard work. This involved pulling out large bushes. With a positive straight leg raise at 40 degrees, the most probable diagnosis is herniated lumbar disk.

About two-thirds of adults experience back pain some time in their life. Sciatica is often used to describe the result of a disk herniation as the sciatic nerve is the downstream nerve effected. A more appropriate term is lumbar radiculopathy. This is due to the proximal origin of the issue and the sensory and motor findings that presents along the sciatic nerve distribution.

Herniated Lumbar Disk

To help with patient education of a herniated lumbar disk, accurate modeling of the nucleus pulposus and annulus fibrosus is developed by Dynamic Disc Designs Corp. Now, a patient can understand the geometry and forces involved to create a disk herniation and may think twice about repeating the activity that causes the problem initially. Accurate patient education of herniated lumbar disk to reveal the mechanism of the injury is very helpful in the management of the condition. This is both in onset and rehabilitation as load with flexion causes the nucleus to push posteriorly.

herniated lumbar disk. lumbar, disk

Herniated lumbar intervertebral disk – important for patients to see how this happened

It is important for patients to understand what caused their symptoms as to change future behaviours. It is known that a herniated lumbar disk is caused by hydraulic compression of overloading the spine into a flexion moment as the posterior annulus is compromised causing radial fissures 2. And now, this never before seen event can be shown with a knowledge transfer to the patient in an easily understandable dynamic model to help improve outcomes.


  1. Richard A. Deyo, M.D., M.P.H., and Sohail K. Mirza, M.D., M.P.H. Herniated Lumbar Intervertebral Disk. The New England Journal of Medicine. May 5, 2016 1763-72
  2.  Samuel P. Veres, BEng, Peter A. Robertson, MD, Neil D. Broom, PhD The Morphology of Acute Disc Herniation. A Clinically Relevant Model Defining the Role of Flexion. SPINE 2009 Volume 34, Number 21, pp 2288–2296
osteoarthritis model, spine, facet, disc height loss

Osteoarthritis is a burden on the people of this world and a major cause of disability. It is considered a degenerative disorder, affecting the aging population as it erodes cartilage, disrupting subchondral bone, leading to osteophytosis, muscle weakening and inflammation to the structures within the joint. 1 An accurate osteoarthritis model would be very helpful for spine.

Historically, osteoarthritis has been looked at from the perspective of cartilage wear with newer insights and interest at the subchondral level. (sub = below + chondro = cartilage) In a paper published in Arthritis and Research Therapy, researchers gave special attention to the subchondral bone. 2

In the perspective of the spine, disc height loss has an influence on the facet joints which are synovial joints. 3 It is disc height loss (a measure of vertebra approximation or closeness) that has shown to have the greatest impact on the biomechanics of a spinal motion segment. In particular, it narrows the intervertebral foramen, causes disc bulging as well as annular stress, and the narrowing can have an effect on the vascular flow in and around the nerves that exit the spine directly influencing nerve roots. There are few other degenerative conditions that can have such a large impact effect on the musculoskeletal system. 4

In Figure 1. of Subchondral bone in osteoarthritis: insight into risk factors and microstructural changes 2 a beautiful histological image showcases the microanatomy of the: calcified cartilage, uncalcified cartialge, the subchondral bone along with the tide mark and cement line of a normal synovial joint. This is an important area of the facet joint.

osteoarthritis model

As mechanical stress is placed onto the uncalcified cartilage, stress will translate through this avascular structure and into the subchondral bone. Chondrocytes secrete glycosaminoglycans (GAGs) and collagen type II-rich extracellular matrix (ECM) that are essential for the maintenance and regeneration of the cartilage which acts to protect subchondral bone. 6 Articular cartilage is mainly water, contributing to 80% of its weight. 7 Interestingly, we have seen that there is a diurnal variation of the cartilage in cartilage 8 similar to what we see in the discs. 9

The bottom line is our tissues that marry our bones together are dynamic and are in constant change to mechanical forces. Disc height loss of the spine will cause the facet joints in the spine to compress and lead to arthritis if not carefully managed.

Dynamic Disc Designs develops models to help in the greater understanding of how a compressed disc can have a multitude of mechanical effects on a spinal motion segment. Understanding the load distribution as it occurs naturally with diurnal variation, lying down, or with injury lifting, or prolonged sitting can be of great assistance in managing the treatment of spinal osteoarthritis as a result of disc height loss and facet arthrosis. Patient education proves to improve outcomes of osteoarthritis when patients understand what not to do first and secondly, why it is important to continue to do safe exercise. 6

The Professional LxH Model demonstrates hyaline cartilage and perichondrial vascularization, while the Lumbar Spinal Stenosis Model demonstrates subchondral sclerosis helping in the education of facet osteoarthritis. A dynamic osteoarthritis model for spine is important to have if educating is a part of a physician’s clinical life.

“Helping doctors be better teachers”

  1. Grynpas MD, Alpert B, Katz I, Lieberman I, Pritzker KP: Subchondral bone in
    osteoarthritis. Calcif Tissue Int 1991, 49:20–26.
  2.  Li et al. Arthritis Research & Therapy 2013 2013, 15:223
  3.  Arbit, E., Pannullo, S., 2001. Lumbar stenosis: a clinical review. Clin. Orthop. Relat. Res.(Mar), 137–143.
  4.  Disc height loss and restoration via injectable hydrogel influences
    adjacent segment mechanics in-vitro Christian Balkovec , Andrea J. Vernengo, Stuart M. McGill Clinical Biomechanics 36 (2016) 1–7
  5.  Li et al. Arthritis Research & Therapy 2013 2013, 15:223
  6.  Blazek AD, Nam J, Gupta R, Pradhan M, Perera P, Weisleder NL, Hewett TE, Chaudhari AM, Lee BS, Leblebicioglu B1, Butterfield TA, Agarwal S. Exercise-driven metabolic pathways in healthy cartilage. Osteoarthritis Cartilage. 2016 Feb 27. pii: S1063-4584(16)01025-6. doi: 10.1016/j.joca.2016.02.004. [Epub ahead of print
  7.  The basic science of articular cartilage: structure, composition, and function. Sophia Fox AJ, Bedi A, Rodeo SA. Sports Health. 2009 Nov;1(6):461-8.
  8.  J Biomech. 2013 Feb 1;46(3):541-7. doi: 10.1016/j.jbiomech.2012.09.013. Epub 2012 Oct 24. Diurnal variations in articular cartilage thickness and strain in the human knee.Coleman JL, Widmyer MR, Leddy HA, Utturkar GM, Spritzer CE, Moorman CT 3rd, Guilak F, DeFrate LE.
  9.  Botsford, D. J. MD; Esses, S. I. MD, FRCS(C); Ogilvie-Harris, D. J. MB, FRCS(C)  In Vivo Diurnal Variation in Intervertebral Disc Volume and Morphology. Spine: April 15, 1994
  10.  Blazek AD, Nam J, Gupta R, Pradhan M, Perera P, Weisleder NL, Hewett TE, Chaudhari AM, Lee BS, Leblebicioglu B1, Butterfield TA, Agarwal S. Exercise-driven metabolic pathways in healthy cartilage. Osteoarthritis Cartilage. 2016 Feb 27. pii: S1063-4584(16)01025-6. doi: 10.1016/j.joca.2016.02.004. [Epub ahead of print
Human spine models, modeling, anatomical models, patient education

A Selection of Human Spine Models Make Patient Education Easier

Most individuals don’t really enjoy going to their doctor, no matter what the reason, be it a routine checkup or for a problem that they’re worried might be serious. Some people get nervous at the mention of a doctor visit and others see their blood pressure spike when they enter any medical office. Experts call this “White Coat Syndrome”.

Why does this occur? One reason is very obvious. The patient is afraid that they’ve developed a serious disease. Unfortunately, sometimes that’s the case. But in many instances, the anxiety comes from the fear of the unknown. In other words, patients don’t know what will transpire when they’re in that office. For that reason, patient education that involves talking about what’s wrong and how it will be fixed is essential.

For chiropractors, who often deal with patients who are in severe pain, this education is super important and should be done on the first visit after an overall assessment is performed. The fact that this instruction is done at all is obviously essential, but how it’s done is even more important. In short, chiropractors who use human spine models to educate their patients produce patients who are more satisfied with their care and who are pleased that they can walk out of the office knowing the facts about their pain and what can be done to fix it.

Human spine models from Dynamic Disc Designs (ddd) are continuously touted as the best available in this category. That’s because they’ve been designed and crafted by an experienced chiropractor who starting making these models because he was frustrated by the tools available for patient education.

Spine modeling, human, spine, models

Posters, while perfect for decorating office walls, just didn’t do the trick. After all, it’s tough to portray a disc bulge via a flat picture of the spine. Dr. Fryer, the owner of ddd, also found that the static models available for patient education didn’t fit what he needed to help his patients. Though 3-dimensional, they didn’t move like the spine moves, making it difficult to portray any number of spine-related problems. That’s why his human spine models move, making it possible for a patient to truly grasp the workings of the spine and why theirs isn’t functioning properly.

Dynamic Disc Designs offers a large selection of human spine models. In the “lumbar” category, the most popular is the Professional LxH model, which includes a flexible and totally dynamic herniating nucleus pulposus as well as a host of other features, including an audible release feature.

“This is the best model I’ve see,” opines Dr. Robert Gregory Lusk. “As a strong visual learner myself I’ve always appreciated that aspect of the educational process with patients. The moving parts accurately demonstrate how the lumbar spine functions. The disc is particularly impressive as it demonstrates the biomechanics involved with compression, flexion/extension, and rotary forces.”

In the “cervical spine” category, Dr. Fryer offers the Professional CxH model, which is a matching specimen to the Professional Lumbar LxH model (same human spine) portraying  identical cervical size with natural morphology including a two-part intervertebral disc with six degrees of natural motion with a red post-lateral nuclear migration upon manual compression, posterior longitudinal ligament (PLL), anterior longitudinal ligament (ALL) and periosteal fascia (POL) (adjacent to uncovertebral joint).

Many chiropractors choose more than one human spine model for their practice. As a matter of fact, Dynamic Disc Designs offers a Patient Educator Bundle, which combines 7 of the companies most popular models at a drastically-reduced price over what would be paid if they were purchased separately.

Check out the vast selection of human spine models available from ddd. Remember, with the proper education, your patients’ fear will lessen and they’ll develop confidence in you and your profession.

Larger Vertebra Model

Enlarged Vertebra Model – using #patientengagement tools

Over the years many people have asked Dynamic Disc Designs Corp. whether we could build a model 2 or 3 times the size for easier viewing. As we understand the need for some to see a larger than realistic model, our company is focused on delivering realistic sized models. Our models are geometrically identical to life size and because we adhere to our strict anatomical core values, there is a simple solution for those customers looking for a larger than life model. It is called a magnifying glass.

The intent is not to be cheeky but practical. There are many links where you can find magnifying glasses. We recommend the 90mm 10x.

Larger Vertebra Model

Having the patient hold the magnifying glass while you point to the posterior annulus and the dynamic nucleus, for example, can be a very effective way to incorporate and educate patients about internal pain generators when looking through our clear bone models. Those with deficiencies in seeing or those that want to have a closer look at the anatomical details of the spine can do it by looking through a magnified lens.

Magnified Clear Bone

So before you consider buying a larger than realistic model from somewhere else, consider a realistic size model by Dynamic Disc Designs Corp. and on the side, find yourself a nice magnifying glass to engage your patients in patient education.