We offer a range of diagnostic tests to help identify and treat your condition or injury. Your provider will use what they learn from the tests to develop a custom treatment plan that meets your specific needs.
Discography is a diagnostic test your doctor uses to find out if your neck or back pain is being caused by damaged spinal discs. It’s also called a discogram.
The doctor uses a special type of X-ray called fluoroscopy to place a small needle in each spinal disc to be tested. The doctor then injects a sterile liquid that’s visible on the X-ray.
If a disc is the source of your pain, the injection should cause the same pain. The doctor uses the test to tell which disc is causing pain and to help decide on the best treatment. You also might have other tests, such as X-rays or a CT scan.
This is an outpatient procedure that usually takes less than an hour. You will be given sedation and local anesthetic.
Your pain might get worse for a few days or a week after discography. Your doctor can prescribe medication. You should not eat before the procedure, and you will need someone to take you home afterward. Specialists at the OHSU Spine Center will explain the procedure and follow-up care in more detail.
Electromyography, or EMG, is a diagnostic test that measures the electrical activity inside your muscles. Because muscles produce electrical signals when they contract, electromyography can help your doctor see if they’re working correctly.
You might have an EMG if an imaging test such as an MRI doesn’t adequately explain your symptoms or if the doctor thinks more than one health problem could be causing your symptoms. An EMG can also help identify nerve problems such as polyneuropathies, or damage to several nerves, that can be caused by conditions such as diabetes.
It takes about 30 minutes to test one arm or leg. Your doctor does a brief history and physical exam to identify the muscles that need to be tested. Next, the doctor places very thin needles, about the size of acupuncture needles, in the muscles. The needles go about one-eighth to one-quarter inch under the skin. The doctor can test three to seven muscles at a time.
The needles are connected to a machine that produces graphs, sounds or numbers to indicate how well your muscles are working. Your doctor will ask you to relax and then gently contract the muscles. The needles pick up electrical activity in the muscles and send the signals to the machine. The results show the doctor which nerves or muscles, if any, are damaged.
Your doctor might send a mild electrical current to the muscle through a needle or small patch (electrode). This feels like a small static electricity shock. Some people describe the feeling as a strong tap. Another needle or electrode picks up the signal and sends it to the machine.
OHSU is one of only two Oregon hospitals with the EOS Imaging System, which offers advanced scanning for pediatric and adult spine conditions, including scoliosis. Compared with other imaging systems, benefits include:
- Significantly better image quality.
- Less radiation than a traditional X-ray or CT scan.
- Full-body images that allow a better understanding of how your bones relate to one another.
- 3D images that help in surgical planning available.
- High quality weight-bearing images that provide an understanding of how the spine, hip and knee compensate for injuries and conditions.
- Available to both children and adults.
How it works
The EOS Imaging System takes a low-dose image from the front and side at the same time. It can take full-body images or focus on a specific body part. A micro-dose option is ideal for follow-up scans. Images can be taken with the patient standing, bending, squatting or sitting.
What to expect
- You will be guided to the EOS scanner — a large, L-shaped X-ray machine.
- A technician will help you get in the right position.
- The technician will run a 30- to 40-second laser positioning process to make sure you’re in the right position.
- Scans take about 15 seconds for children and 20 seconds for adults.
Why it matters
- Better images help your doctors make a more precise diagnosis so they can better plan treatment.
- Less radiation means less risk of future health problems, especially for those with conditions such as scoliosis that need regular scans, often over years.
- Faster images mean more comfort and convenience for you.
- OHSU has the only EOS system for adult spine patients between Seattle and San Francisco.
Nerve conduction studies measure how quickly electrical signals travel along your nerves. The studies, also called NCS, offer one way to test how well your nerves are working. You might have NCS if an imaging test such as an MRI doesn’t adequately explain all your symptoms or if the doctor thinks more than one health problem could be causing your symptoms. NCS can help identify nerve problems such as polyneuropathies, or damage to several nerves, caused by conditions such as diabetes.
It takes about 30 minutes to study one arm or leg. Your doctor does a brief history and physical exam to identify the nerves that need to be tested, then tapes small electrodes over muscles to evaluate individual nerves.
The testing itself takes only a few minutes. The doctor uses a stimulator to send a small electrical charge to the nerves. A machine connected to the electrodes records how long the signal takes to travel along nerves. The machine creates graphs, sounds or numbers that tell your doctor how well the nerves are working.
The electrical charge feels like a small static electricity shock. Some people describe the feeling as a strong tap. The results tell the doctor if a specific nerve in your back, arm or leg is causing the problem.