Ask the Expert: Dr. Austin Fragomen, Orthopedic Surgeon, Answers Your Questions on Knock Knees
Q1. What causes knock knees and can they be corrected? What is the impact on the ankles, knees and hips?
There are many causes for genu valgum (knock knees). Most cases are developmental, where people are born with the deformity and it becomes more noticeable with time. An injury to the growth plate in a child can also lead to knock knees. Knock knees can be surgically corrected. The surgical technique used may vary depending on age.
Knock knees can affect the ankles and knees as well as the hips. This is a form of misalignment and it can cause increasing pressure and pain in the front of the knee because the knee cap is off center. The ankles may struggle to keep the foot flat on the ground. The ankle and foot will need to compensate to make up for misalignment at the knee, often leading to ankle pain. Abnormal hip rotation is often associated with knock knees and can cause hip pain. This needs to be recognized and addressed with any corrective surgery for the knock knees.
Q2. I have knock knees as well as hip and back issues. Is there any correlation?
Knock knees can be associated with knee, hip and back pain. Furthermore, correction of the deformity will often alleviate the pain. If a patient is overweight and has knock knees, then losing weight will help the hip and back pain. Knock knees are often related to leg length differences. A leg length inequality will often lead to hip and back pain. Having the legs equalized will help treat the pain. Consult with a physician for the best course of treatment.
Q3. Is knock knee surgery possible on someone in their late twenties?
Yes, there is no age limit for corrective surgery for knock knees. The surgical technique used may vary depending on age. Children can take advantage of their remaining growth to guide the bones straighter with minor surgery. Adults can benefit from osteotomy surgery on the knee to obtain a correction. Older patients with arthritis will often receive a knee replacement to treat both problems with great success. It is important to consult with a physician to determine the best course of treatment.
Q4. Can knock knees get worse over time?
The deformity can get worse in some cases. In children the deformity can progress with growth. If arthritis is present, the deformity can progress as the joint wears out further. In adults the medial ligaments of the knee can stretch and cause greater deformity.
Q5. Are there any non-surgical treatments for knock knees?
The best non-surgical treatments are aimed at reducing the risk of arthritis development in the knee. This includes maintaining a low body weight, keeping fit while avoiding high impact activities (running, soccer, singles, tennis, basketball, etc.) and bracing. These treatments will not change the knock knee deformity but they will help in reducing the functional problems associated with the deformity. Talk with a physician about the best treatment for you.
Dr. Austin Fragomen is an orthopedic surgeon and the director of the Limb Lengthening and Complex Reconstruction Service at Hospital for Special Surgery.