Pain control after total knee replacement is an important postoperative goal. Surgeons have found that injecting a numbing agent in and around the joint work well in reducing the need for narcotic drugs after surgery.
Adding a steroid to the injected fluid may help control inflammation. But there’s an increased risk of infection with steroids and the possibility of an allergic reaction. It’s not entirely clear that adding a steroid is really needed. A recent study from a well-known clinic specializing in joint reconstruction studied the question of whether adding a steroid gains patients any additional pain relief.
They compared two groups of patients having a total knee replacement. One group had the injection with the steroid (steroid group). The second group had the standard injection without the steroid (no-steroid group). No one in either group knew what type of injection they were getting. Their surgeons didn’t know what type of injection was being given. That research method is called a double-blind study.
All surgeries were performed by one surgeon who had advanced training in joint reconstruction. A periarticular approach was used for all injections. This means a little bit of the contents of each syringe was squirted around the knee ligaments where they attached to the joint, around the synovium (lining of the joint holding lubricating joint fluid), and along the back of the knee where the joint capsule (fibrous cartilage) is accessible.
Results were measured by looking at levels of pain, how much narcotic medication was needed/used during hospitalization, and how long each patient stayed in the hospital. They also measured range-of-motion of the knee and performed a test called the Knee Society score to gain an idea of knee function. These two tests of motion and function were done before and after surgery. Any problems or complications were recorded.
The authors thought the steroid group would do better with shorter hospital stays, improved motion, better function, and no real increased problems afterwards compared with the no-steroid group. What really happened was the steroid group got out of the hospital faster, but there wasn’t any difference in their pain levels, joint motion, or function. And there were some serious complications in the steroid group that did not develop in the no-steroid group. Each of those patients had unique circumstances contributing to the complications. The role of the steroid in those complications wasn’t clear, so can’t be ruled out entirely.
The authors conclude that adding a steroid to the injection given during total knee replacement surgery isn’t necessary. There was no clear benefit to it and safety concerns remain. Comparing the results of this study with other similar studies showed the authors that the other medications used in the no-steroid group are really effective and better than steroids at controlling pain.
Be sure and talk with your surgeon about your history and concerns. Reviewing in advance any potential problem areas can help save you worry and possibly reduce the risk of complications.