When you have a rotator cuff tear, your shoulder is painful and difficult to move. The pain is due to the injury to the muscles and tendons that help move your shoulder. According to the Cleveland Clinic, this injury is often accompanied by pain at night, which is sometimes severe enough to interfere with sleep. Your doctor will use at least one of six possible methods to diagnose whether your injury is indeed a rotator cuff tear.
Comprehensive Physical Exam
Your doctor will ask you how the injury happened and will check your shoulder for pain, tenderness, weakness and loss of motion, especially for a loss in overhead movement. She will ask you to move your arm in all directions to assess your range of motion. While you are doing this, your doctor will watch you for signs of increased pain. Your doctor will ask you if the pain began at a gradual or rapid pace. He will also assess your desire to keep the shoulder inactive. Tears to the rotator cuff muscle can be full or partial. In an article published in the July 2006 issue of "Clinical Inquiries," lead author Dr. Sabina Diehr states that while full-thickness tears weaken shoulder muscle strength, partial tears might not impact shoulder strength and they can be harder to diagnose.
X-ray
Often, your doctor will order an X-ray to check whether your shoulder pain is caused by a bone spur or some other structural abnormality. If your pain is due to a fall, the X-ray will show the doctor whether you have a broken bone or an injury to the shoulder joint's ball and socket.
Arthrogram
An arthrogram is conducted when the doctor injects a contrast dye into your shoulder joint and then takes an X-ray or magnetic resonance images (MRI) to see where the dye goes. Normally, the dye is confined to a specific area. Dye that spreads into the shoulder's soft tissue signifies a torn rotator cuff.
Magnetic Resonance Imaging
An MRI uses magnets, radio waves and computers to create detailed images of your shoulder and its surrounding structures. The images are three-dimensional, allowing the doctor to see your injury from all sides.
Ultrasound
Ultrasound images are created with the use of a wand placed on your skin. The wand transmits video images of your shoulder area and is the same equipment used to show expectant mothers their babies inside the womb. The ultrasound images can show your doctor whether your shoulder muscle tendons are intact or not. Dr. Diehr concluded in her study that even though either an MRI or an ultrasound can confirm whether the muscle tear is full or partial, an ultrasound is best for verifying partial-thickness tears.
Arthroscopy
Arthroscopy is a minimally invasive surgical procedure where your doctor inserts a small instrument into your shoulder joint to look directly at your rotator cuff. If you do end up having a rotator cuff tear, arthroscopy is also how it will be repaired. Your doctor will use the arthroscope to trim torn tendons and stitch or apply anchors to larger tears. Since the muscles and tendons cannot heal on their own, surgery is almost always required with full-thickness rotator cuff tears.
