Have you experienced a knee injury and noticed a few twinges or stabs of pain? Or maybe you’ve had successful knee surgery and still feel persistent discomfort? You’re not alone.
Some athletes who have undergone arthroscopic knee surgery to address the meniscus or the ligaments can still have debilitating pain around the knee despite a successful orthopedic procedure. This can be extremely frustrating for the athlete who is trying to get back in the line-up or competition.
Persistent pain can result in significant downtime away from your sport, additional time spent in physical therapy, and even additional knee surgery to make sure the repair is intact. However, in cases where the pain does not appear to have any orthopedic-related causes or the pain is localized on the 1-2 specific areas on the skin or near the scars, some of the small nerve branches in the skin could be irritated or damaged.
If you’ve already had knee surgery but still have nerve pain on the surface, board-certified surgeon Anthony Echo, M.D., in Houston, Texas, specializes in diagnosing and treating nerve injuries around the knee.
Keep reading to see how you can better determine if you have an injured or scarred nerve from a prior surgery and how our practice can help.
How do I know if my pain is related to a nerve injury versus an orthopedic issue?
If you’ve injured your knee or you are in the immediate postoperative period, your orthopedic surgeon is going to be your first line for evaluation and treatment. However, if you are still having nerve pain after the standard postoperative period, then you might have a nerve issue.
1. The pain is reproducible with pressure
Nerves follow a consistent pathway and occupy a specific area. When a nerve is injured or scarred, there is usually a small area which is extremely painful and tender to touch. This is usually located near a scar. Pressure on that area will produce a sharp, electrical pain months after a surgery which can be debilitating for the athlete.
2. There are no other orthopedic explanations for the pain
If you have completed your knee rehabilitation as prescribed, but there is still pain, your orthopedic surgeon may order additional studies. However, for patients who have a normal orthopedic exam and no findings on x-rays or MRIs, the nerve could be involved.
If your orthopedic surgeon cannot find an orthopedic source for your persistent pain after surgery and rehab, then the sensory nerves could be involved.
3. Nerve block to diagnose the problem
Once a nerve injury is suspected around the knee, your physician may determine that a nerve block is appropriate. This is usually performed with a small amount of lidocaine (a common numbing medication) which is injected just below the skin where the pain is located.
If the pain goes away within a few minutes, then this means that there is potentially a scarred or injured nerve.
If the nerve block does not work, then the nerve in the skin is not likely the main source of pain.
What nerves are commonly involved?
While orthopedic surgeons operating on the knee work hard to avoid the nerves around the knee during surgery, everyone's anatomy is slightly different and there is no way to predict every deviation in your anatomy. In many cases, the small nerve branch is just scarred from the normal postoperative swelling. There are 3 main nerves around the knee which can be affected.
1. Saphenous nerve
This nerve emerges on the inner thigh above the knee then runs just behind the inner knee, before running toward the inner ankle. This nerve can be injured from a nerve block or during surgery. When the saphenous nerve is affected there could be numbness or pain down the inner leg and focal pain at the incision.
2. Infrapatellar nerve branch
The infra-patellar nerve is a branch of the saphenous nerve and runs just below the kneecap. This is probably one of the most common nerves to be injured from the placement of the ports or an open incision at the knee. Patients with this nerve injury will have pain when anything bumps their knee or when resting their knee on the ground.
3. Common peroneal nerve
The common peroneal nerve can be compressed at the outer knee. Many patients have a baseline compression around this nerve, then the injury or surgery resulted in swelling around the nerve, thereby tightening the tunnel that it runs through. When this nerve is strangulated, you may experience foot drop, pain at the lateral knee, or numbness on the top of the foot.
What can be done if the nerve block was successful?
While orthopedic knee surgeries aim to rectify issues caused by an injury, sometimes they can inadvertently cause postoperative nerve issues.
Once you have been diagnosed with a nerve issue around the knee and have failed conservative therapy, then surgical intervention might be necessary. We recommend that you exhaust our conservative treatment with your orthopedic surgeon, and in some cases you might require a pain management physician to offer further minimally invasive options. However, for patients who have chronic nerve pain 6-12 months after a surgery and a documented nerve problem, then a peripheral nerve surgical procedure might be necessary.
Each surgical procedure is tailored to the specific nerve involved and the type of injury. Some of the nerves can be decompressed to remove the band of tissue squeezing it while other nerves might require removal of the damaged segment. Some of the nerves branches can be quite small and require a peripheral nerve surgeon to trace out the nerve and branches to help alleviate the pain.
Seeking expert help
When such symptoms emerge, it's crucial to consult a board-certified surgeon who specializes in nerve repair for personalized recommendations and advice.
Dr. Echo has years of experience with this type of post-surgery injury. For example, Dr. Echo may recommend treatment to release the compressed nerve, easing your pain and restoring nerve function so you can resume your physical activities.
For personalized recommendations on preventing chronic knee pain after an injury or previous knee surgery, schedule a consultation online or over the phone at Anthony Echo, M.D.