Shoulder MRI (without contrast)

What it is

The shoulder is the loosest joint in the body. The ball sits against a shallow socket and is held in place almost entirely by soft tissue — a cuff of four tendons, a rim of cartilage around the socket called the labrum, and a set of ligaments. That design is what lets the arm reach anywhere, and it is also why shoulder problems are usually soft-tissue problems. An x-ray shows the bones and the space between them and says nothing about any of it. This scan is the one that shows the tendons themselves: whether the cuff is frayed, partly torn, torn through, or pulled off the bone, and how far retracted the torn edge is. Nothing is injected in this version. Where fluid has collected in a joint that is inflamed or torn, that fluid does much of the work a dye would otherwise do.

Why it is done

• To find out whether a rotator cuff tendon is torn, and if so how big the tear is and whether the muscle behind it has wasted
• To investigate shoulder pain that has not responded to rest, injections or physical therapy
• To look at the labrum and the biceps tendon after a dislocation or a wrenching injury
• To find a fracture that a plain x-ray missed, or an area of dead bone
• To look for infection or a tumor in the bone or the surrounding soft tissue
• To check the state of the joint before a planned operation, and to look at progress after one

What to expect

Metal screening comes first and is thorough, because the magnet is never switched off. For the scan the arm is positioned at the side, palm up or in a set rotation, and a coil is strapped around the shoulder. One practical quirk of this study: the shoulder has to sit near the middle of the magnet, so the body lies off to one side of the tube rather than down the middle, which can feel more enclosed than a head or knee scan. The requirement is stillness, for roughly twenty to forty-five minutes, with ear protection against the noise. Nothing is injected, there is no preparation, and you can drive home. A radiologist reads the images and reports separately.

Questions worth asking

• Check whether the order says plain MRI or MR arthrogram. An arthrogram means a joint injection and image guidance billed on top of the scan, and a different, costlier MRI code.
• Orthopedic practices increasingly own their own scanner. Ask whether being imaged there versus at the hospital changes the total, and whether the practice bills the scan and the reading together.
• Ask for the facility's self-pay or cash price alongside the insured estimate. For an unenhanced extremity MRI the two are often far apart.
• Ask whether your plan requires prior authorization for shoulder MRI and whether a course of physical therapy has to be documented first, because a denial after the scan leaves the bill with you.
• Ask that the images be released to you on disc or through a portal, so a second opinion does not turn into a second scan.