ANATOMY IN ACTION SERIES: Understanding X-ray Fundamentals
Educational articles designed to help CA’s understand the underlying anatomy and physiology of conditions or issues presenting to the chiropractic office.
Laurie Mueller
BA, DC, CFMP
X-ray as a Tool
In the chiropractic office x-rays are an important tool to help DC's look deeper into a patient's skeletal structure and alignment. Some offices take X-rays as a standard procedure to rule out underlying pathology (like a possible tumor, infection, fracture if there has been trauma, or osteoporosis in folks at risk). If a patient has been in an accident or trauma, X-rays are typically indicated as a prudent part of care and best practice.
In cases of non-traumatic musculoskeletal pain, many offices may offer a trial of care for the patient before moving on to X-rays. (Eg. If no other findings or history indicate risk). This type of approach has been supported in our research. For example one review study found that in a sample of 340 X-rays, 15% showed a significant pathology that changed treatment recommendations. For the other whopping 85% there were no clinically significant findings found on the films. The conclusion of this review and other similar reviews is that unless a thorough clinical evaluation specifically indicates the need for X-rays, it is not warranted and exposes the patient to unnecessary radiation. With that said, it may be reasonable to consider X-ray if there is an absence or plateau in symptom improvement after a trial of care.
Note that some specific technique styles also specifically require X-ray analysis as part of the process, so offices practicing such techniques will utilize X-rays routinely. In this article we are going to walk you through a few select X-ray findings, and whatthey may mean clinically.
X-ray Basics
First a reminder of the basics. X-rays are a type of electromagnetic radiation (just like visible light). An X-ray machine will send individual X-ray particles through the body and the images are recorded on a computer or film. Digital computer images are becoming the norm due to their clarity and the ability to focus in on specific areas.
Structures that are very dense, like bone, will block most of the particles from reaching the recording
media and thus will appear white on the image. Things like metal (or if contract media is used) will also appear white. Structures containing air will be black and tissues like muscle, fat and fluid will appear as shades of grey. It takes special skills to read them. Your DC has been trained in chiropractic school, however, there are a variety of cases when the DC may send the X-ray out for a more formal radiology report from someone that has had extra specialized training in the area of reading X-rays.
When X-rays are taken, how the patient is positioned against the Bucky wall will indicate where the beam will go through the body and what structures can be seen in the final image. Special breathing techniques may be used when taking chest or thoracic films to clear the lungs of air and provide a clearer image. It is important that patients also wear a gown and take off anything with metal (piercings, zippers on clothing, hooks or underwire on braziers, necklaces, belts etc.) as those things will obstruct the view of the anatomy that needs to be seen. In this image if the patient had
a spur, tumor or other abnormality underneath the zipper or buckle, the doctor would not be able to find it. We also can't fully visualize the symphysis pubis cartilaginous space. To radiate a patient and not be able to see the desired anatomy due to not attiring them properly in a gown is radiating for nothing.
Patients will also wear an apron or be shielded to protect body parts (like gonads) from receiving radiation if that area of anatomy is not the focus of the study. Note that we avoid ever radiating a pregnant patient as it can cause harm to the unborn. Asking all female patients to confirm that they are not pregnant and even sign a release form stating such is common practice. It is also important that the staff who are taking X-rays (such as CT's/chiropractic technologists who have special training to position patients and take Xrays) or anyone else near the X-rays also stand behind a lead wall and wear protective clothingto reduce risk of unnecessary radiation. Things like dosimetry badges can be worn by staff to help monitor exposure.
Alignment and Degeneration
X-rays are highly useful to visualize spinal alignment and to provide indicators of degeneration. The healthy spine demonstrates a nice S-shape that features a C-shaped lordotic (forward) curve in the cervical, a kyphotic curve in the thoracics, and another lordotic curve in the lumbar region. If diminished one of the goals of your doctor will be to try to help the patient restore those natural curves.
We also look for signs of degeneration. The image on this page shows a progression from an optimal spine, to one with alignment change to more profound stages of degeneration. You may notice than phases 3 and 4 both have very diminished disc spaces (the darker areas between the vertebrae) and the bones have started to lip, spur with osteophytes, misshape and in final stages even fuse. This is important information to have as it can affect the patients range of motion, and if bone spurs or fusion has occurred it can alter what techniques the DC may use to adjust the region or if certain segments need to be avoided.
About the Disc Space
We mentioned earlier that soft tissues like fat or muscle show up as shades of grey on X-ray. The intervertebral discs consist of fibrocartilaginous tissue and they contain a fair amount of water so they are significantly darker than bones. Please understand that disc space degeneration does NOT automatically equal a disc herniation or mean that there is a disc bulge in that area. Similarly, a healthy sized disc space does not mean that there isn't a disc bulge. What degenerated disc space means is that the biomechanics of that area were altered enough and for a long enough period of time to cause a degenerative
change. The DC may approach the patient very differently if they are treating a disc bulge vs. working with degeneration only. Symptoms and examination will lead the DC to their initial diagnosis. However, special imaging may be indicated as a follow-up to confirm the exact disc location in the spinal anatomy, and how large it may be. Where X-ray is great to look at bone, a CT or MRI scan allow better visualization of soft tissue. The doctor can then use this information when applying different traction or techniques so that they are targeting the exact location of the bulge.
Osteoporosis
Lastly we'll mention osteoporosis as it can be a significant threat, particularly with our older patients. The process replaces regular bone with a weaker, brittle, more porous bone that can result in fragility fractures. Osteoporosis itself really has no recognized symptoms, but it is actually the most common reason for a broken bone among the elderly. Sometimes the pain or fall from a broken bone is the first clue a patient has. Finding it early is important so that patients can start on bone strengthening exercise, engage in nutrition that can support healthy bones, and co-care with other doctors if indicated. Keep in mind, however, that abnormal finding in X-ray are not always detectable until more than 30% of bone density is reduced. In older patients, the DC may opt for a baseline CT or DEXA scan to better gauge the degree of osteoporosis and risk for fracture in certain patients. The stage of the process can also greatly affect how we choose to adjust the patient. In the early stages we may not have to do much differently, but in later stages DC's will opt for very low impact gentle adjusting procedures. They may also find it prudent to avoid traction which can stress the brittle bone, and avoid strenuous physiotherapy such as Russian Stim EMSthat can cause sudden jerking on tendon on bone that may result in injury in these patients.
The more you understand, the better you can help support patient care. At your next staff meeting ask your doc to show a few X-rays and explain how they use the information to benefit their patients!
Laurie Mueller, BA, DC, CFMP served in private practice in San Diego, California. She was the postgraduate director at Palmer College from 2000-2010; served as the ACC Post Graduate subcommittee chair for 6years; peer reviewedfor the Research Agenda Conference, and wrote the informal role determination study that aided in the development of FCLB's guidelines for chiropractic assistants (CCCAs). Dr. Mueller currently works as a private eLearning consultant with a focus on healthcare topics and functional medicine through her company, Impact Writing Solutions LLC, and subsidiary www. CCCAonline. com. She is a clinician, an educator and an expert in online educational pedagogy.
