“The clinical diagnosis shows a disc bulge in their neck and some arthritis, so their neck symptoms are not associated with the crash. Lots of folks have those and do not have pain although it could be a minimal herniation. It’s our diagnosis that it was there before the crash.” This statement from an adjuster is an argument that has been made for many years, allowing insurance companies to inappropriately reduce settlements to their clients based on the client’s inability to prove when or how the damage or injury occurred. To factually counter this sort of statement, an individual must use imaging and age dating to discuss causality. Without medical experts utilizing the current medical and academic research available, it will continue to be difficult for any argument to be made explaining effects of these injuries and their mechanism based on fact vs. rhetoric.
Imaging of the spine is critically important in most cases of injured clients. In cases, imaging is necessary for proper diagnosis and future management of injuries. Imaging needs to be performed as per the academic and modern criteria to ensure an accurate diagnosis. The most common injuries in car accidents are spinal related, and the simple imaging available includes x-rays, CAT scans and magnetic resonance imaging (MRI), allowing medical providers to make an accurate diagnosis, when medically indicated.
Every medical provider has a permit to see and treat automobile related injuries. However a “license” is not the same as “specialization.” By way of example, though psychiatrists may have a license to do heart surgery and are MDs, it would not be in the patient’s best interest. Nor would I go to a spine surgeon for psychological concerns although they are licensed to treat medical conditions. In spinal trauma, certain suppliers specialize in connective tissue injuries of the spine, allowing us to go one step farther in diagnosis, prognosis and management, including “age-dating” these generally found disc and ligament injuries.
Understanding Age-Dating of Injuries
To understand age-dating, one wants to have a basic medical understanding of anatomy and physiology, and what tissue is commonly injured and the probable “pain generator”. Since neck injuries are the most common injuries cervical joints will be our focus. Related to anatomy, every set of two vertebrae in the neck is connected with three joints; two facet joints and a single disc. These joints allow for normal movement of the spine (mobility). There are multiple ligaments that are responsible for stability and hold together these joints. The correct balance of mobility and stability is critical when looking at the part of patient’s injuries, meaning that too little or too much movement in spinal joints can lead to pain, secondary to damaged tissue. The tissue most commonly hurt in a car crash is nerve, ligament, disc, facet and muscle/tendon. Spinal cord and bone injuries also happen although less frequently. To determine causality, the supplier should comment on what tissue is injured, and also use imaging to help determine if this injury occurred (age-dating).
There are two fundamental problems that must be addressed. Fardon and Milette (2001) reported, “The phrase ‘herniated disc’ does not infer knowledge of cause, relation to trauma or activity, concordance with symptoms, or need for treatment” (p. E108). Simply having a disc herniation’s presence, without a physical exam or without symptom documentation that is appropriate, does not allow one to comment on the cause of the injury. In a rear impact collision by way of example, even if the diagnosis is confirmed, additional criteria will need to be fulfilled to answer the question of “Was there sufficient force generated into the vehicle and the occupant to induce the cervical/lumbar herniation?” Fardon, in a follow-up study (2014) reported that disc injury “in the absence of significant imaging evidence of associated violent injury, should be classified as degeneration rather than trauma.” (p. 2531). Thus, we must more objectively define the subjective connotations of “violent injury” and address the issue of “degeneration as opposed to trauma”. Although this statement can frequently be misleading, it gives the trauma trained expert doctor a basis in going forward understanding that every patient’s physiology is unique and not subject to rhetoric, but clinical findings.
Violent injury to the occupant can occur when there are sudden acceleration and deceleration forces (g’s) generated to the neck and head which overwhelm connective tissue or pull them past their physiological limit. To determine the acceleration force, ΔV (delta V) is utilized. ΔV is the change in speed of the occupant vehicle when it is hit from behind (i.e., going from a stopped position to seven mph in 0.5 seconds because of forces moved from the “bullet” vehicle to the “target” vehicle). Utilizing these data, research allows us to make specific comments related to violent injury. Since the cervical spine is subjected to shearing forces, and compression, tension we are oversimplifying. Along with g-forces and the elastic nature of the majority of rear impact crashes makes it almost impossible to discover an actual minimum threshold for injury even though the literature has given us many examples of low-speed crashes which are dependent not simply on speed, but the mass (weight) of the subject vehicles. Each individual’s susceptibility to injury is unique. While g-forces alone are insufficient to predict injury, Krafft et al. (2002) reported that in low-speed collisions there’s an injury threshold of 4.2 g’s for males and 3.6 g’s for females. Krafft’s analysis is unique in that she has access to insurance data inaccessible to researchers. Panjabi (2004) revealed that forces as low as 3.5g impacts would lead to damage to the front of the disc, and 6.5g and 8g impacts would lead to disc damage posteriorly where the neurological components are.
Diagnosis for Disc and Ligament Injuries
A spinal biomechanical expert can look for evidence that is conclusive by disc and pathology, according to two phenomena. First, it is recognized that the body is electric. We’re measuring activity to diagnose when an EMG is done. Second, there are bioelectrical fields in all tissues. This typical field is disrupted when an injury occurs, and in the case of joints calcium is drawn to the damaged tissue. Issacson and Bloebaum (2010) reported “The particular loading pattern of bone has been documented as a significant piezoelectric parameter since potential gaps in bone have been known to be due to charge displacement during the deformation period” (p. 1271). For the patient, we have the ability to tell just how much of this process has occurred before or after their crash, especially if we take into consideration the tissue damage and signs of bone/calcium deposition.
In addition, the body begins a healing process that includes regeneration and remodeling of the soft and hard tissue as reported by Issacson and Bloebaum (2010). Spinal vertebrae have a unique structure of bone which allows it to adapt to abnormal mobility and stability (injury) by changing shape, which can be found on radiographs or MRI. Moreover, shape will change according to patterns based on the pressure or load it undergoes post-injury. Issacson and Bloebaum stated that “Physical forces exerted on a bone change bone structure and is a well-established principle…” (p. 1271). This is a further understanding of a scientific principle called Wolff’s law established in the 1800’s. Because we know what “normal” is, when we see “abnormal” findings as a result of mechanical stress we could broach the topic of an acute injury versus a degenerative process being the cause of the abnormality and create specific medical predictions accordingly.
He and Xinghua (2006) studied the predictability of the bone remodeling process and were able to make predictions of pathological changes that will occur in bone, specifically the osteophyte (bone spur) on the edge of a bone structure. Significantly, they noted their findings “confirmed that osteophyte formation was an adaptive process in response to this change of mechanical environment”. They noted that factors are crucial to the morphology of bones, particularly bones such as the femur and vertebrae.
For readers familiar with current academic and medical accepted nomenclature for disc injury, recognized from the combined task forces of the North American Spine Society (NASS), the American Society of Spine Radiology (ASSR) and the American Society of Neuroradiology (ASNR), disc herniations must have a directional component. When this occurs, the additional and abnormal pressure at the level of the disc damage matched with the direction of the herniation will cause that section of the vertebrae.
Thus, if there’s a C5/6 right sided herniation (protrusion/extrusion) secondary to a cervical acceleration/deceleration injury, then only that side of the vertebrae will change shape, creating an osteophyte. Facet arthritis is additionally caused by this compounded loading on the facet joint. This process is very similar to the formation of a callous on your hand or foot. The callous is a recognized and expected tissue response to increased load/friction exposure. Similarly, an osteophyte is a known and anticipated bone response to a rise in load/friction exposure.
At a basic level, the body has an electrical and mechanical response to injury leading to additional stress that leads to calcium (bone) to flow in the region of injury to further support the joint. The joint then abnormally grows, developing a called hypertrophy, degeneration, disc osteophyte complex, or arthritis/arthropathy, common terms seen in the reports of doctor and radiology.
Everybody is subject to these morphological (structural) changes, always and predictably determined by mechanical imbalances in the spine. He and Xinghua (2006) concluded that, “…it will actually take about over half a year to discover the bone morphological changes…” (p. 101). This indicates that it takes approximately six months to get an osteophyte (bone spur) to be demonstrable post-mechanical breakdown or failure. This again provides a time frame to better understand whether pathology of the intervertebral disc has been present for a long period of time (pre-existing) or has been produced as the direct result of the specific traumatic event by deficiency of the existence of an osteophyte, meaning the disc pathology is less than six months old, dependent on location and management of the pathology.
In conclusion, that by definition, a disc is a ligament connecting a bone to a bone and it has the structural responsibility to the vertebrae above and below to maintain the spinal system in equilibrium. Damage to the disc because of a tear (herniation or annular fissure) or a bulge will create abnormal load-bearing forces in the injury site. These present differently based on  if traumatic failure on the side of the disc lesion, or  if age related, as a general complex. Since other research and human subject crash testing have defined the term “violent trauma” as not being dependent upon the amount of damage done to the vehicle but rather to the forces to which the neck and head are exposed, we can now accurately predict in a demonstrable way the timing of causality of this disc lesion. This depends upon the symptomatology of the the morphology of the structure and is a subject that can be predicated upon speculation or rhetoric.
The scope of our information is limited to chiropractic and spinal injuries and conditions. To discuss options on the subject matter, please feel free to ask Dr. Jimenez or contact us at 915-850-0900 .
- Fardon, D. F., & Milette, P. C. (2001). Nomenclature and classification of lumbar disc pathology: Recommendations of the combined task forces of the North American Spine Society, American Society of Spine Radiology, and American Society of Neuroradiology. Spine, 26(5), E93–E113.
- Fardon, D. F., Williams, A. L., Dohring, E. J., Murtagh, F. R., Rothman, S. L. G., & Sze, G. K. (2014). Lumbar Disc Nomenclature: Version 2.0: Recommendations of the combined task forces of the North American Spine Society, American Society of Spine Radiology, and American Society of Neuroradiology. Spine, 14(11), 2525-2545.
- Krafft, M., Kullgren, A., Malm, S., and Ydenius, A. (2002). Influence of crash severity on various whiplash injury symptoms: A study based on real life rear end crashes with recorded crash pulses. In Proc. 19th Int. Techn. Conf. on ESV, Paper No. 05-0363, 1-7
- Batterman, S.D., Batterman, S.C. (2002). Delta-V, Spinal Trauma, and the Myth of the Minimal Damage Accident. Journal of Whiplash & Related Disorders, 1:1, 41-64.
- Panjabi, M.M. et al. (2004). Injury Mechanisms of the Cervical Intervertebral Disc During Simulated Whiplash. Spine 29 (11): 1217-25.
- Issacson, B. M., & Bloebaum, R. D. (2010). Bone electricity: What have we learned in the past 160 years? Journal of Biomedical Research, 95A(4), 1270-1279.
- Studin, M., Peyster R., Owens W., Sundby P. (2016) Age dating disc injury: Herniations and bulges, Causally Relating Traumatic Discs.
- Frost, H. M. (1994). Wolff’s Law and bone’s structural adaptations to mechanical usage: an overview for clinicians. The Angle Orthodontist, 64(3), 175-188.
- He, G., & Xinghua, Z. (2006). The numerical simulation of osteophyte formation on the edge of the vertebral body using quantitative bone remodeling theory. Joint Bone Spine 73(1), 95-101.
Additional Topics: Weakened Ligaments After Whiplash
Whiplash is a commonly reported injury after an individual has been involved in an automobile accident. During an auto accident, the sheer force of the impact often causes the head and neck of the victim to jerk abruptly, back-and-forth, causing damage to the complex structures surrounding the cervical spine. Chiropractic care is a safe and effective, alternative treatment option utilized to help decrease the symptoms of whiplash.