The MRI: When and Why to Order One

As I lecture around the country to both chiropractors and medical specialists, it's clear one of the main disconnects between the two professions is that of an accurate diagnosis. In teaching both chiropractic at the doctoral level and medicine at the graduate medical level, I have learned this disconnect arises due to standards of care. Too many doctors of chiropractic fail to utilize diagnostic tools such as magnetic resonance imaging (MRI), believing the adjustment can heal everything; while others only order MRIs for legal cases, pandering to the plaintiff's lawyers. Others order MRIs indiscriminately, not fully understanding the protocols or standards when determining the necessity for an MRI.

Before I outline the protocols / standards, let's briefly explore why an MRI could and/or should be ordered in the chiropractic-mechanical spine paradigm. Fracture, tumor or infection (nonmechanical spine issues) are a different conversation; this article focuses only on mechanical spine issues.

The Question of Necessity

Regardless of your technique, ancillary modalities (distraction, traction, etc.) or belief system, the first step for any health care provider is to make an accurate diagnosis, followed by a prognosis and then a treatment plan – all prior to rendering treatment. Part of the problem in chiropractic is that too many practitioners want to rush to treat before fully understanding what is going on in their patients. That is both problematic and not in the best public interest, as too many people can potentially get hurt – regardless of the doctor's good intentions.

Briefly summarized, the clinical protocols that are consistent with the literature and academia standards when it comes to ordering an MRI are as follows: Should there be significant radiculopathic clinical presentation of any myelopathic findings, no matter how mild, an immediate MRI is warranted prior to care. The central issue is what is causing that clinical presentation. No matter how good an adjuster you are or how good your modalities are, you don't know unless you look. You cannot repeat the mantra, "I know the patient will get well," and then adjust them without a conclusive diagnosis. It is not an appropriate standard of care and not in the best public interest.

To help clarify the necessity issue, a radiculopathic finding is any motor or sensory aberration in the limbs or radiating around the flanks inclusive of aberrant reflexes, foot drop, sensory deficit or hyperesthesia; in short, anything that can be affected at the root level from both the anterior and posterior horn innervations. A myelopathy is cord compression with ensuing deficit distal to the level of the lesion.

Unfortunately, most in the profession have not had adequate doctoral training on both of those basic findings that a spine specialist must have, as must our profession, if we aspire to be spine specialists. We must be expert in both. That is the purpose of postdoctoral or graduate training, and it is each individual doctor's responsibility to seek that training to ensure they are an expert in the basics of a spine specialist.

The purpose of the MRI is to determine if there is a space-occupying lesion that will alter the treatment plan. MRIs should never be used as a screening process to see if something can be found, as in a personal-injury case. That is both improperly pandering to an attorney and not within any standards of care.

Should a space-occupying lesion be found, such as a herniated disc, the doctor then has to determine if there is enough room between the lesion and the neurological element to safely adjust the patient. Sometimes it is prudent to simply wait until the disc shrinks or desiccates and recedes off the neurological element (cord or root) to safely adjust the patient. However, should there be any contact on the cord or root, unless the doctor is expert in interpreting MRI, the first step in triage is to refer this patient to a neurosurgeon for consultation to help determine if conservative care is warranted.

Should there be adequate room between the disc and the neurological element, there is then demonstrable evidence that it is safe to adjust the patient with minimal risk. As the adjustment increases intrathecal pressure, the disc will expand during the adjusting process; in that expansion, should the disc be too close to the cord or root, it can cause injury to that area.

Interpreting MRI: Considerations

It is my goal for you, the doctor, to be the expert in interpreting MRI images yourself, and be able to independently make that decision based upon a combination of clinical presentation and clinical findings followed by the MRI images. Although we all trust the general radiologist, according to Lurie, Donovan, Spratt, Tosteson and Weinstein (2009), there is a 42.2 percent error rate in rendering an accurate description of the morphology of the disc. 1 That means general radiologists are wrong 42.2 percent of the time and according to many leading neuroradiologists, that figure is probably significantly higher today.

Therefore, it is incumbent upon each of us to learn at least the basics of MRI spine interpretation to verify the radiologist's interpretation is accurate. It also provides a platform to have a peer-to-peer conversation to reach a consensus on the diagnosis.

There are some very good courses that can give you a solid foundation to start interpreting MRI, but you need to go beyond a few hours in a hotel room. Any program you choose should also have a strong section on pathology beyond the disc to help you fully triage your patients.

What you learn in chiropractic college gives you the minimum to pass your boards and start treating patients. That is your beginning, but what you do after graduation is solely your responsibility. So take your graduate education seriously and demand high-quality programs from your state organizations. It matters!

  1. Lurie JD, Doman DM, Spratt KF, et al. Magnetic resonance imaging interpretation in patients with symptomatic lumbar spine disc herniations: comparison of clinician and radiologist readings. Spine, 2009;34(7):701-705.

Editor's Note: Part 2 of this article will discuss what to do once you have the MRI findings in hand.