A knee replacement requires the removal of bone and cartilage, so a person can expect some pain while healing after the procedure. Because the nerves in the hip and knee joints come from the same area, pain from a knee replacement can cause hip pain.
Knee replacement surgery is a common procedure that replaces a damaged joint with a prosthetic one. A person may need a knee replacement for several reasons, including osteoarthritis, rheumatoid arthritis, and knee injury.
In some cases, people may experience hip pain after knee replacement. This pain is usually a typical part of the healing process and goes away on its own. However, it may be a sign of complications such as infection or nerve damage.
Read more to learn why hip pain happens, how much pain a person can expect, how to manage it, and more.
It makes sense to expect hip pain after hip replacement surgery, but why would someone experience it after a knee replacement procedure?
Although it seems confusing, hip pain after a knee replacement can actually be a typical part of the recovery process. The nerves in both the hip and knee joints originate from the same area, so issues with the nerves in the knee can cause pain or discomfort in the hip and vice versa.
There are several common causes of this hip pain, including:
- Hip osteoarthritis: Sometimes, hip osteoarthritis can present as knee pain. When this occurs, a person may get a knee replacement when they actually need a total hip replacement.
- Nerve and tissue inflammation: Nerve irritation and inflammation during surgery may cause temporary numbness, discomfort, or pain in the knee. This can then radiate to the hip.
- Biomechanics: After surgery, a person may have biomechanical changes and walk or move differently. These subtle differences can affect the hip, causing pain or soreness. After surgery, the body — which has likely gotten used to walking a certain way and is perhaps compensating for an injured knee — will need to adjust as a person learns to walk with the new joint.
- Referred pain: According to a
2018 study, some people present with knee pain that comes from the hip. Doctors call this referred pain. People with referred pain may receive unnecessary knee replacement surgery for a problem that actually stems from the hip. After surgery, they may continue to experience pain, including hip pain.
- Masking: This can happen when a person has both knee and hip osteoarthritis, and the knee pain masks the hip pain. Once the knee replacement fixes the knee osteoarthritis, an individual can notice the hip pain.
Most people can expect mild to moderate pain when recovering from knee replacement surgery. If pain continues once a person has fully healed, it may be time to talk with a doctor. Additionally, severe pain that makes it difficult to sleep or function as usual likely requires medical attention.
A person could return to their everyday activity 3–6 weeks following knee replacement surgery. However, they may still experience pain for several months. These times will vary from person to person, and a doctor can advise what to expect during the healing process.
Increasing pain and the following symptoms may even be a sign of infection, a potential complication with any surgery. Signs of an infection include:
- the wound is warm to the touch
- tenderness and swelling
- high fever
- visible redness that radiates from the wound area
- pain that gets worse whether a person is moving or resting
- worsening stiffness
- drainage from the wound
It is important to note that knee joint infection is rare and occurs in less than 2% of knee replacements.
Blood clots are a more common complication and can cause pain in the legs. A person may have a blood clot if they:
- feel a persistent leg cramp-like feeling
- have skin that is red or warm to the touch
- experience swelling in the leg
Pain that occurs in the hip after knee replacement surgery may be due to several factors, including:
- nerve or blood vessel damage
- blood clots
- problems with the new knee joint
Changes in biomechanics after knee surgery may also lead to hip pain on the same or opposite side of the knee joint replacement.
It is also possible that in people with degenerative conditions, such as osteoarthritis, hip pain can happen because the hip joint has become damaged in addition to the knee joint.
In most cases, hip pain after knee replacement surgery is a typical part of the healing process and will go away on its own.
However, it is important to have realistic expectations for the recovery period. Mild to moderate pain is typical after this kind of surgery and should gradually improve with time.
People can relieve pain and discomfort with the following strategies:
- Rest, ice, compression, and elevation: Rest is a crucial part of the recovery process. Without proper rest and reduced activity, healing may take longer, and the risk for complications may increase. Additionally, applying ice, using a compression dressing, and elevating the affected knee can also help relieve pain and swelling.
- Pain relievers: People may also find it helpful to use prescription or over-the-counter pain relievers. Examples of pain relievers that can help reduce swelling and pain include nonsteroidal anti-inflammatories, acetaminophen, and prescription opioids.
- Other medications: A doctor may also recommend other medications, such as muscle relaxers, to help with recovery.
- Exercises: Some people may find that exercises may help strengthen hip muscles that have weakened over time due to favoring one leg.
If a person experiences chronic pain in the hip that does not resolve with rest and home treatments, they may wish to follow up with a doctor.
An individual should contact a doctor if hip pain interferes with their daily activities. And if pain persists after the wound has fully healed, they can discuss this with a healthcare professional.
Additionally, if someone suspects they have a joint infection or blood clot, they should seek emergency medical care.
Most people will find they have significantly less pain after knee replacement surgery, but some pain during the recovery period is typical.
In some cases, individuals may undergo knee replacement surgery and later discover that pain originates in the hip. Nerve and other tissue damage may also lead to pain in the hip after knee replacement surgery.
It is crucial that people consult their doctor about the potential risks and complications of knee replacement surgery. Having a complete picture of what to expect during the recovery process can help a person recognize when pain requires a visit to the doctor.