What Is Needle Arthroscopy for Knee Pain?

There are many common types of knee problems that cause people to visit their healthcare providers. To determine the source of the pain, practitioners will use information obtained through their discussion with patients, their examination of the knee, and various tests. In addition, a new diagnostic tool has recently become available for healthcare providers.

Having an arthroscopic surgery in an operating room means that your healthcare provider looks inside of a joint through an instrument called an arthroscope. During a knee arthroscopy (one of the most common types), your practitioner inserts a camera into the joint to evaluate and treat many conditions that can lead to painful knee joints.

Healthcare providers are now starting to perform arthroscopy right in their offices through a procedure called a needle arthroscopy—this is performed using smaller instruments and without making a surgical incision. Learn more about how to know if this is an appropriate procedure for you to evaluate your own knee pain.

The Procedure

Needle arthroscopy is performed in your surgeon's office. The procedure typically takes about 15 to 20 minutes to perform. Your surgeon will begin by cleaning the area around your knee and anesthetizing the location for the insertion of the needle arthroscope.

The local anesthesia routinely used is Xylocaine 2% with adrenaline. Once the area around the knee has been anesthetized and sterilely prepared, your surgeon will insert the needle arthroscope.

The needle arthroscope is attached to a camera and light source that allows your surgeon to inspect within the joint. The arthroscope can be inserted into several different locations depending on the area of suspected damage within the joint. The most common location in which to insert the arthroscope is just inside or outside of the patellar tendon, underneath the level of the kneecap.

In order to better visualize the inside of the joint, your surgeon will intermittently irrigate the joint with sterile saline solution. A small burst of fluid will be intermittently pushed into the joints and can be suctioned out upon completion of the procedure.

Diagnostic Tool

A needle arthroscopy is primarily a diagnostic tool. This means that your surgeon has a limited ability to actually treat any condition that is found, unlike when surgery is performed arthroscopically in the operating room. The reason to perform a needle arthroscopy is essentially to make a proper diagnosis and to determine if further intervention might be necessary.

Post-Procedure

Following the needle arthroscopy procedure, a small bandage will be placed on the joint, and your surgeon may use a larger compressive bandage to help prevent swelling into the joint. Depending on the pain level experienced by the patient and the amount of swelling and trauma around the knee, your surgeon may allow you to fully weight-bear (put your full weight on your knee) and walk out of the office.

If not, she may recommend using crutches for a short duration to allow the joint to settle down. Over-the-counter (OTC) pain medications are typically sufficient to control any symptoms of discomfort following this procedure.

Many people who undergo needle arthroscopy return to normal work activities either the same day or the day following their procedure.

Advantages

There are several advantages to performing a needle arthroscopy compared to other diagnostic tests, such as MRIs.

Immediate Results

Compared to an MRI which needs to be scheduled (and the results may take some time to return) a needle arthroscopy can be performed immediately, offering immediate answers to the source of knee pain. This may mean fewer trips to the hospital and fewer imaging tests.

Accuracy

In addition, MRIs are known to miss some problems, and they can be difficult to interpret in certain circumstances (such as when a person has undergone a previous surgery).

Cartilage Damage

When planning for a surgery such as autologous chondrocyte implantation (ACI) or osteoarticular cartilage transfer (OATS), a needle arthroscopy may provide your surgeon with more accurate information about the size of a cartilage defect.

Arthritis

In terms of arthritis, a needle arthroscopy can be helpful in determining if knee replacement or partial knee replacement may be necessary. A challenge for surgeons is determining when arthritis may be too extensive to allow for arthroscopic surgery or partial knee replacements versus having a full knee replacement. Needle arthroscopy can provide some useful insight into evaluating the extent of arthritis.

Dynamic Evaluation

Finally, needle arthroscopy allows your surgeon to evaluate the knee joint in a dynamic fashion. This means that your surgeon can have you move the joint while they are looking inside at the structures of the knee. This may be useful in determining the stability of the joint and cartilage within. This type of dynamic evaluation is not possible with routine MRI imaging.

These are some of the reasons why surgeons are starting to utilize this tool more frequently—especially because it allows patients not to undergo more extensive surgery.

The needle arthroscopy can help to address some of the shortcomings of other tools that are used to diagnose knee conditions.

Disadvantages

Not every surgeon feels that a needle arthroscopy has reached the point of being routinely useful.

Diagnostic Tool Only

The major disadvantage is the fact the needle arthroscopy remains primarily a diagnostic tool, and not a treatment modality. This means that even if your surgeon locates an area of damage, a formal surgical procedure in the operating room is likely to be necessary in order to correct that.

Complications

In addition, there are possible complications of needle arthroscopy. These complications include pain during the procedure, infection, bleeding, and the possibility of damage from the needle arthroscopy procedure (iatrogenic damage).

Probably the most significant of these concerns is the possibility of septic arthritis. When this occurs, infection enters into the joint making surgical intervention and long-term antibiotics necessary. Septic arthritis is a concern any time the joint space is entered.

While performing needle arthroscopy is not highly invasive, any time a needle enters the joint there is the possibility of introducing infection. The risk of these complications is low, but it is not negligible. An argument can be made that an MRI provides similar information to the needle arthroscopy without the exposure to these potential risks.

Limited Information

Lastly, while a needle arthroscopy does provide real-time visualization of the structures within the knee joint, it does not provide any information about structures that surround the joint including muscles, tendons, ligaments, bursa, and other structures that can lead to symptoms of knee pain.

Therefore, it is possible that the true source of discomfort may not be visualized as well through a needle arthroscopy as with a test such as an MRI, which will visualize these surrounding structures just as well as those inside the knee joint.

The Costs

There is also a debate as to whether or not needle arthroscopy represents cost savings or an added cost. If your surgeon uses needle arthroscopy in place of an MRI, this certainly represents savings in cost. By not having to perform the MRI, surgeons who use needle arthroscopy can be saving money by not performing additional tests.

By performing the needle arthroscopy at the time of the visit evaluation, there is also potential cost savings in avoiding unnecessary follow-up visits.

However, there are also many situations in which surgeons perform MRI tests and a needle arthroscopy together. In these situations, it is more difficult to make an argument that the needle arthroscopy is a complete savings.

Over half of arthroscopic surgery on the knee joint is used for the treatment of cartilage and meniscus damage. Performing needle arthroscopy as a diagnostic tool rather than using an MRI has an estimated savings between $115 to 177 million to the healthcare system each year in the United States.

However, note that these figures assume that surgeons will perform needle arthroscopy instead of (not in addition to) performing an MRI.

Other Joints

Needle arthroscopy is most commonly used to evaluate the knee joint, and most of the published reports on the procedure are focused on the evaluation of the knee joint pathology. However, needle arthroscopy has also been used in other joints, including the shoulder, elbow, and ankle.

For example, shoulder evaluation by needle arthroscopy in the office has been used to diagnose tears of the labrum and tears of the rotator cuff. Needle arthroscopy of the ankle joint can be used to diagnose areas of cartilage damage, and needle arthroscopy of the elbow can be used to identify loose cartilage within the joint.

A Word From Verywell

Minimally invasive surgical interventions are a popular subject for patients and surgeons. A needle arthroscopy procedure of the knee joint is an effort to provide a convenient and effective way to diagnose many common knee problems without the risks of surgery. However, there are limitations to a needle arthroscopy. Surgeons who perform this procedure agree that routine use of needle arthroscopy is not always appropriate. It is best to discuss your options with your healthcare provider to determine what the best course is for you.