The Pros and Cons of Ultrasound-Guided Injections

Ultrasound-guided injections allow healthcare providers to see the needle in real-time as it enters the body and is injected into a precise spot. Orthopedic surgeons often use injections to treat a variety of conditions. Commonly injected medications include cortisone, local anesthetics, and joint lubricants such as hyaluronic acid.

In some cases, delivering an injection is not as easy as it sounds. Some require you to hit the target just right, often with the slimmest margin of error. Ultrasound-guided injections reduce the risk of errors or complications during such injections.

This article explains the pros and cons of ultrasound-guided injections. It touches on how the procedure is done, why it is controversial, and alternative methods available.

What Are the Benefits of Ultrasound-Guided Injections?

Ultrasound-guided injections are valuable for healthcare providers for several reasons. The use of ultrasound imaging allows providers to:

• Identify a precise "point of interest" or target area in the body to make the injection
• Guide the needle while viewing it in real time on a monitor
• Assure the injection is delivered to the exact spot where it is needed

Ultrasound is beneficial both for healthcare providers and their patients because it:

• Improves the accuracy of the injection spot
• Improves the effectiveness of the injection
• Lacks radiation, unlike computed tomography (CT)
• Can be repeated as many times as necessary without risk
• Lowers the risk of complications, such as puncturing nearby blood vessels or nerves
  

There is clear evidence that ultrasound-guided injections provide superior pain relief and a faster recovery compared to injections made without image guidance. The treatment's success is largely due to its accuracy.

What Conditions Do Ultrasound-Guided Injections Treat?

Ultrasound-guided injections are used to treat a variety of conditions related to the musculoskeletal system, including joints, muscles, tendons, nerves, and the fluid-filled sacs that cushion joints (bursae).

The technique is commonly used to treat:

• Osteoarthritis
• Rheumatoid arthritis
• Pain due to soft tissues trapped in a joint, often due to inflammation (impingement)
• Frozen shoulder syndrome
• Inflammation of the soft tissues connecting muscles to bones (tendonitis)
• Muscle tears
• Inflamed bursas (bursitis)
• Carpal tunnel syndrome, which causes numbness and tingling in the hand due to a pinched nerve in the wrist
• Chronic pain due to overuse injuries
• Pain in the sciatic nerve (sciatica)

Injections of botulinum toxin (botox) are sometimes done using ultrasound guidance, as well as aspirations (retrievals) of various tissues, including breast and liver tissues, for needle biopsy.

What Are the Drawbacks of Ultrasound-Guided Injections?

There has been an ongoing debate as to whether ultrasound-guided injections are worth all the fuss. Much of the dissent comes from insurers and private payers who cite two main objections:

• Healthcare providers should be given more thorough injection training, rather than relying on ultrasound guidance for accuracy.
• Ultrasound-guided injections may add unnecessary costs to a bill.

While there is some validity to these points, the fact remains that certain types of injection procedures are more challenging than others. Not to mention, differences in human anatomy can further complicate procedures, particularly in people with certain musculoskeletal conditions.

For example, delivering a lumbar puncture is especially challenging in people with conditions like ankylosing spondylitis, which causes spinal vertebrae to fuse. Ultrasound guidance allows providers to find a safe path for the needle through complex and abnormal spinal anatomy. This, in turn, dramatically reduces the risk of puncturing unintended tissues or structures.

What to Expect From Ultrasound-Guided Injections

Ultrasound-guided injections are performed much in the same way as traditional injections. To ensure the images come in clear, an ultrasound gel will be applied directly to the skin. The gel acts as a conductive medium that creates a tight bond between the skin and the ultrasound probe. This ensures the reflected sound waves have minimal interference.

The probe, also known as a transducer, is then placed near or adjacent to the targeted tendon or joint. Once the healthcare provider has identified the anatomic landmarks on the monitor, the injection will be delivered using a standard needle and syringe.

The ultrasound also allows you to visualize fluids so that you can see if the medication is being distributed exactly where you need it to be.

How Long Does an Ultrasound-Guided Injection Take?

Ultrasound-guided injections should not take much longer than traditional injections. In many cases, ultrasound-guided injections take less time and eliminate the need for multiple attempts (in people with more complicated anatomy).

Generally, ultrasound-guided injections should not take longer than one hour to complete. This includes the time it takes to:

• Clean the site around the injection
• Inject a local anesthetic like lidocaine to numb the insertion site
• Prepare the ultrasound and apply ultrasound gel
• Slowly administer the injection under ultrasound guidance

Keep in mind that certain procedures may take longer than others, particularly if you have unique anatomical features due to an underlying musculoskeletal condition.

Recovery

Recovery can vary somewhat depending on the procedure, so you will need to follow your healthcare provider's instructions closely. Your provider may instruct you to:

• Feel free to shower after your procedure, but avoid taking a bath, swimming in a pool, or using a hot tub for 48 hours
• Leave the bandage on for 24 hours then remove it
• Continue using any medications after the procedure
• Use a hot or cold compress to relieve pain and soreness at the injection site

Your pain may take a couple of weeks to improve, and your joint pain may feel worse the day after the injection (steroid injections only). You can take Tylenol to help with the pain.

As with a kind of injection or open wound, it's important to monitor the injection site for signs of infection. Call your healthcare provider if you develop:

• Fever of 100.4 F or higher within 10 days of the injection
• Persisting pain, redness, or swelling at the injection site
• Drainage from the injection site

What are the Side Effects of Ultrasound-Guided Injections?

Although uncommon, side effects and risks associated with injections include:

• Bleeding and bruising
• Temporary facial flushing
• Temporary pain or flaring of joint inflammation
• Temporary rise in blood sugar
• Tendon weakening or rupture
• Thinning of nearby bone (osteoporosis)
• Thinning of skin and fat around the injection site
• Lightening of skin around injection site
• Cartilage damage
• Joint infection
• Nerve damage

Different procedures also come with their own, distinct risks. Be sure to ask your healthcare provider about the risks associated with any procedure they prescribe.

Alternative Procedures

Computed tomography (CT) scanners are commonly used for some guided injections like nerve blocks and typically involve the use of contrast dye to monitor needle insertion. However, research shows that ultrasound may be just as effective as CT scanners for certain injections, minus the risk of radiation.

If your healthcare provider orders an injection guided by CAT scan or MRI, feel free to inquire about having an ultrasound-guided injection instead. This is particularly important to consider if you are paying out of pocket, since ultrasounds tend to be far more cost effective than CT scans, MRIs, and other imaging modalities.

Summary

Ultrasound-guided injections provide pain relief in a number of conditions, including arthritis, pinched nerves, and bursitis. Compared to traditional injections, ultrasound-guided injections tend to take less time and are more effective, as the procedure allows for more precision. Most ultrasound-guided injections take less than an hour to complete. The risk of side effects varies somewhat depending on the procedure, but overall, it's low.

While ultrasounds are a great alternative to other imaging modalities, they may not be right in every case. If you have questions about ultrasound-guided injections, talk to your healthcare provider.