Why Did My Orthopaedic Surgeon Order An MRI?
As an Orthopaedist (or Orthopaedic Surgeon), I can diagnose a lot of problems and injuries by listening carefully to your symptoms, how you got them and by doing a thorough examination. Other times things like X-rays and MRIs are necessary to be more thorough.
Sometimes my experience may make it seem like I can see through your outer layers and into your joints, muscles and bones. Other times things like X-rays and MRIs are necessary to be more thorough.
So, for what common purposes are the different types of “imaging” used?
What is an MRI and Other Common Body Scans?
Magnetic resonance imaging uses a really powerful magnet to see the soft tissues that X-rays don’t show well. I can see:
- Damage and more subtle wear from arthritis or injury to the cartilage on the bone, the meniscus or labrum (which act like spacers) in the joint
- Ligament tears or stretches
- Bruising in the muscle, tendon or bone
- Muscle strains or tears
- Inflammation or damage to the tendons
- Fluid collections
I use X-rays to be able to see the condition of bones. With X-rays I can see fractures or breaks in the bone – which, contrary to some popular beliefs, are the same thing.
I can also see some of the signs of arthritis such as bone spurs or bumps of bone where there should not be any — which is why your joints often feel enlarged with arthritis. The narrowing of the space between the bones at joints indicating wearing of the cartilage is something else I can also see. Usually see the cartilage itself is not doable, unless there are calcium deposits which are also a sign of arthritis.
I can see dislocations of joints when they don’t line up properly after an injury. I can also see if bones have weakened with age or disease – known as osteoporosis.
CAT Scan vs MRI
A CT or CAT scan is like a much more sensitive X-ray and can show me the above things from many angles. An MRI uses a magnet to view tissues.
I can use ultrasound to get a moving picture, or real-time view, of muscle, tendon and bone if they are not too deep in the body.
Sometimes I use ultrasound to assist in injections or look for the cause of popping or clicking that the other studies can’t show since they don’t show movement well.
I can also use ultrasound to look for blood clots in veins, but this is usually done by another type of doctor.
Less often I will order bone scans to look for areas that a bone is trying to heal or strengthen itself. This usually means I will order one if I am looking for:
- A stress fracture
- Shin splints
- Loosening of a total joint replacement
- Other similar issues
It is less sensitive than the other studies but is often used to help focus in on a more specific location for the diagnosis.
This is different from a bone density study which looks more specifically for osteoporosis.
Most often, I will need more than one of these types of studies to paint a more complete picture of a diagnosis. Each one provides something that adds to homing in on the correct issue and, therefore, developing the right treatments.
So, don’t be surprised if I have to order more than one type of study – it’s how I can treat you best and these “pictures” are often worth a thousand words.
Stay healthy. Keep moving.