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.

children and back pain

The goal of this study?

The objective of this study 1 examined the causes and risk factors for lower back pain (LBP) in children and adolescents who accessed a specific clinic.

Why are they doing this study?

LBP is common in children and adolescents, with existing research showing the prevalence of LBP ranging from 9%-69%, increasing significantly between 12 and 18. While research shows that LBP causes in children are as diverse as adults, there is much less information on LBP in children and adolescents. 

Who was involved?

The research looked at patients under 18 who came to the researcher’s clinic to address LBP between May 2014 and May 2018.

 

  • A total of 106 children and adolescents, aged between 8 and 17:
  • 55 girls (51.8%) & 51 boys (48.1%)

 

Those excluded included:

  • Anyone with referred pain, infections or anyone with emotional or mental stressors that are causing pain.

What was done?

The researchers used a retrospective study for their design, meaning that all of the patients were already experiencing LBP, and they look back in time to determine why.

 

The researchers looked at a variety of patient data, including:

    • demographic information (age, gender, ethnicity, etc.), 
    • pain severity, which was measured using a visual analog scale (VAS)
    • physical examinations
    • laboratory tests
  • Imaging using X-ray and MRI 
  • Family history
  • Lifestyle, including how much sitting per day, sporting activity
  • Examination for hypermobility and hamstring flexibility

 

Statistical analysis of all the data was done using SPSS (which is stat software) to determine…

What did they find?

The researchers found six different etiologies (causes) for LBP in children and adolescents. Overall, they found that LBP was more common in their adolescent patients than younger children. 

 

The vast majority of patients in this study, 62 (58.4%), had non-specific LBP. These patients had various risk factors, including obesity, poor posture, tight hamstring muscles, hypermobility, family history and immobility. All patients in this group had their symptoms resolved either independently or through the use of rest and analgesic medication. Additionally, all patients in this group were given a home exercise program.

 

The second most common cause was lumbar disc herniation, with 24 patients (22.6%). The causes of this were mostly related to trauma and family history. Treatment for these patients varied from steroid injections, analgesic medication, physiotherapy and three patients with uncontrolled pain required surgery.

 

Inflammatory LBP was the third most common findings, with 6 patients (5.6%). All of these patients were treated with non-steroidal anti-inflammatory drugs, exercise and referred to a pediatric rheumatologist.

 

Among the remaining patients, 5 had spondylolysis-listhesis (a crack or stress fracture in one of the vertebrae, the small bones that make up the spinal column), 5 had scoliosis, and 4 had Scheuermann disease (a childhood disorder where the vertebrae grow unevenly and can result in a humpback). Patients in these categories were treated with various approaches, including analgesics, rest, physiotherapy and exercise.

Why do these findings matter?

Determining the cause of LBP in children and adolescents is important to address pain and mobility issues for young people and because it is a significant risk factor for adulthood. If not diagnosed and treated appropriately, it may become chronic and cause disability in adulthood. 

osteophyte

The patterns of vertebral osteophytosis (or the growth of bony projections from vertebrae) is a common study among researchers. The actual cause of these bony outgrowth projections has been questioned over the years, with some pointing to the abnormal movement patterns of motion segments. Others have questioned this and believe the cause to be related to age and genetics. In a 2014 paper, researchers sought to answer: Is vertebral body osteophytosis a reliable indicator of occupational stress1. A shallow dive into their findings will be shared here.

What we do know from the work of Kumareson et al. 2 and Adams & Roughley 3 is that osteophytosis looks to be linked to degeneration of the intervertebral disc which is defined by an aberrant, cell-mediated response to progressive structural failure. With this structural failure, inevitably, there must be physical stress and thought to influence the cells at the vertebral-disc interface margins to produce bony outgrowths.

Furthermore, others have looked at these bony outgrowths and tried to relate them to aberrant mechanical loading patterns along with physical age and genetics. 4 5 6. Archeologists that study biological remains have used this finding as a tool to measure historical population activity level and lifestyles 7 drawing speculative conclusions on the inter and intra-population differences. Two well documented skeletal population differences demonstrated that the women had more severe osteophytosis than the men and was thought to be caused by heavy lifting that the men did not do during this same time period.

However, other researchers believe that degeneration is not solely related to physical activity and more so related to genetic factors 8, ageing 9, and body mass 10. And with this, one can see the complexities underpinning the causative factors of these bony outgrowths that some call ‘bony spurs’ projecting from vertebrae.

The osteophytes’ anatomical margins are the entheses, which you can see in our Lumbar Spinal Stenosis Model. This is the region where a muscle, tendon or ligament attaches to the bone. It is the interface where force intersects with bony anatomy. This is often represented in the extremities but the same biological process is thought to be at the crux of these anatomical changes.

osteophyte

Osteophyte Projection in our Lumbar Spinal Stenosis Model

What did these researchers investigate?

A group of researchers 1 wanted to see if they could determine whether mechanical factors related to osteophyte formation. They looked at these entheseal margins in the lower and upper extremities and the spine to see if they were correlated. Their logic was to see if the bony osteophytes were similar in all anatomical regions and if so, they could speculate that there was a mechanical influence of the formation of them. They also wanted to see if age played a factor as they explored the relationship between vertebral osteophyte formation and entheseal changes in the extremities.

The samples that were used came from a burial site in Cedynia, Poland. 101 male skeletons were examined and divided into two age groups, 20-40 years old and 41-56 years old. To determine the vertebral osteophyte degree, they used a rating scale developed by Swedborg (1974) to measure the entheseal grade; they used Mysezka & Piontek (2012). The entheseal anatomical sites they measured included the humerus, radius, femur and the tibia.

What they found

Interestingly, the researchers found no significant age differences when comparing the presence and degree of both osteophytosis and enthesopathy in the spine and extremities, respectively. They did find a significant correlation between the lower extremity enthesopathy and the vertebral osteophytosis, however. In other words, if they saw bony spurs in the lower extremities of the specimens, there was a good chance they were going to find vertebral osteophytes of the spine.

 

Does this solve anything regarding whether mechanics plays a role in osteophyte presence?

No. But it does shed light on the possible mechanics. These researchers agreed that other factors, besides physical ones, could be at play and should be considered. In particular, like age, body mass and genetics.

 

Commentary by Jerome Fryer

From a clinical standpoint, we should be mindful of these anatomical changes. Do they cause pain and problems all the time? No. We have seen this time and time again with clinically abnormal imaging findings. However, in the case of vertebral osteophytosis, a projecting osteophyte into the foramen where an exiting nerve root needs room for its vascular geometry for nourishing itself, space is everything. Learning about how to prevent the progressive changes of these types of osteophytes that can encroach on the dorsal root ganglia is important. Ongoing facet arthropathy is an adaptable process, but if adaptation is too great and osteogenesis takes up space where the nerve needs it, pain and disability can present and often, there is no turning back. My hunch is if we can improve the spine’s mechanics and keep an eye on disc height changes over a lifetime, we can keep the spine healthier and avoid spinal conditions like lumbar spinal stenosis. However, this is purely speculative in nature, and much more research on the causes of osteophytosis must occur. JF

 

  1. Anthropol. Anz. 71/4 (2014), pp. 381–389 Notes J. Biol. Clinic. Anthropol. Stuttgart, November 2014
  2. Kumaresan, S., Yoganandan, N., Pintar, F.A., Maiman, D.J. & Goel, V.K. (2001): Contribution of disc degeneration to osteophyte formation in the cervical spine: a biomechanical investigation. – Journal of Orthopaedic Research 19, 977–984. DOI: 10.1016/S0736-0266(01)00 010-9.
  3. Adams, M.A. & Roughley, P.J. (2006): What is intervertebral disc degeneration, and what causes it? – Spine 31, 2151–2161. DOI: 10.1097/01.brs.0000231761.73859.2c.
  4. Sambrook, P.N., McGregor, A.J. & Spector,T.D. (1999): Genetic influences on cervical and lumbar disc degeneration: magnetic resonance imaging study in twins. – Arthritis and Rheumatism. 42, 366–372. DOI: 10.1002/1529-0131(199902)42:2<366::AIDANR20>3.0.CO;2-6.
  5. Spector, T.D. & McGregor, A.J. (2004): Risk factors for osteoarthritis: genetics. Osteoarthritis and Cartilage 12, 39–44. DOI:org/10.1016/j.joca.2003.09.005.
  6. Knüsel, C., Göggel, S. & Lucy, D. (1997): Comparative degenerative joint disease of the vertebral column in the medieval monastic cemetery of the Gilbertine Priory of St. Andrew, Fishergate, York, England. – American Journal of Physical Anthropology 103, 481–495. DOI: 10.1002/(SICI)1096-8644(199708)103:4<481::AID-AJPA6>3.0.CO;2-Q.
  7. Novak, M. & ˇ Slaus, M. (2011): Vertebral pathologies in two Early Modern Period (16th–19th) century) populations from Croatia. – American Journal of Physical Anthropology 145, 270–281. DOI: 10.1002/ajpa.21491.
  8. Sambrook, P.N., McGregor, A.J. & Spector,T.D. (1999): Genetic influences on cervical and lumbar disc degeneration: magnetic resonance imaging study in twins. – Arthritis and Rheumatism. 42, 366–372. DOI: 10.1002/1529-0131(199902)42:2<366::AIDANR20> 3.0.CO;2-6. , ageing and body mass index.
  9. Snodgrass, J.J. (2004): Sex differences and ageing of the vertebral column. – Journal of Forensic Science 49 (3), 458–463.
  10. Oishi, Y., Shimizu, K., Katoh, T., Nakao, H., Yamaura, M., Furuko, T., Narusawa, K. & Nakamura, T. (2003): Lack of association between lumbar disk degeneration and osteophyte formation in elderly Japanese women with back pain. – Bone 32, 405–411. DOI:10.1016/S8756-3282(03)00031-0.
  11. Anthropol. Anz. 71/4 (2014), pp. 381–389 Notes J. Biol. Clinic. Anthropol. Stuttgart, November 2014
Intervertebral disk

Intervertebral Disk Degeneration – Fibrotic Remodelling, Time and Entropy

Lower back pain is an issue on this planet. It affects 632 million people worldwide and plagues 70-80% of US individuals at some point in their lives. The good news is that it is often self-resolving, but repeated bouts’ of recurrence are very frequent. The most popular low back pain diagnosis is intervertebral disk degeneration, with specific structural disruptions often contributing to pain. Therefore it is only logical for researchers to look at this structure to learn more about how the structure contributes to back pain.

We have known for years that the intervertebral disk is composed of two main structural components. The annulus fibrosus, which is the tough criss-cross oriented outer layer and the nucleus pulposus, which is an inner, softer gelatinous structure that holds water to help with the resistance against compression forces. To dive a little deeper, the annulus fibrosus consists of type 1 collagen, and the nucleus pulposus consists of type 2 collagen. If you want to explore the microstructure, you can visit Eyre et al.

The key structural element of the intervertebral disk looks to be the extra-cellular matrix. This is the ‘stuff’ between cells. The scaffolding, so to speak. The infrastructure within that holds things in place—or at least, is supposed to hold things in place.

In highlighting this research, James Iatradis, a well-known spine researcher, assembled a team to look at the intervertebral disk’s microstructure and look closely at what could be going on. In a Special Issue Article in the Journal Spine 1, his team used a special technique, named second harmonic generation imaging (SHG), to quantify the collagen content and structural make-up of intervertebral disk degeneration.

The concept of entropy, which is a physics term to describe order, or lack thereof, helped the researchers describe the disorganization of the degenerated tissue compared to the disk’s non-degenerated tissue. They found the tendency of the degenerated disk to be less organized with an increasing intensity seen with the imaging technique used. In other words, more chaos or entropy signalled disorder of the tissue. Collagen, in its healthy form, is organized. These researchers found the degenerated disks contained less microstructural organization and fibrotic remodelling.

This is an important paper. It demonstrates that tissues change over time. And with structural changes, there must be a biomechanical change. At Dynamic Disc Designs, we understand that the spine is in constant change and with that, we must learn and adapt as we age. Explore our wide-ranging dynamic models with varying properties to help with the education of the spine.

 

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.

Lordosis

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.