Blind Knee Injections: Why is this procedure still being performed?
Knee shots for arthritis? Doctors have injected many things inside knee joints through the years, the most common being steroid injections and hyaluronic acid injections (SynVisc, Orthovisc, Eufflexxa, etc…). More recently these older treatments are giving way to newer biologic therapies like platelet rich plasma and stem cells. However, did you know that the way the doctor performs your knee shot to help your arthritis may determine if the shot works? There are two ways to inject a joint-blind or with imaging guidance. Injecting any joint “blind” means that the doctor doesn’t use any type of imaging guidance and can’t see where the needle is going. The problem is that sometimes with a blind injection the doctor isn’t really in the joint, but just close to the joint. With imaging guidance the doctor can see where the needle is going and watch the medication go inside the joint. To understand this, think of a joint as a capsule of tissue that surrounds the bone and cartilage. If you get the needle inside the joint capsule, then what’s being injected will go inside the joint and contact the bones and cartilage. If you miss that capsule, then the medication or cells never make it inside the joint. In addition, for our stem cell work, we want even more exact placement than just inside the joint, we usually want to be in a specific portion of the joint or in a specific tear or hole in the cartilage. While a good c-arm x-ray machine to help guide the injection can cost as much as a condo, in the last few years relatively inexpensive ultrasound machines have flooded the market-leaving no excuse for any physician to perform a “blind” joint injection. Now research out this week provides many more incentives for doctors to enter the 21st century when it comes to injecting joints. In this study, the use of ultrasound guidance to inject arthritic knees resulted in a 48% reduction in pain from the procedure, 42% more reduction in knee pain, twice as many patients that responded, and treatments that lasted longer. The use of ultrasound for these injections also significantly reduced treatment costs. The upshot? Don’t let anyone inject any joint without the use of imaging guidance (x-ray/fluoroscopy or ultrasound) or you’ll have the “blind leading the blind”.