People who are born with spinal bifida can end up having more chronic health problems, depending on how severe the spinal bifida was and what kind of surgical correction was necessary.
Typically, the types of chronic medical problems that people with a history of spinal bifida can have include trouble with bowel or bladder control and weakness in the muscles of the legs leading to difficulty walking or, in some cases, inability to walk.
Spinal bifida can also be associated with some severe orthopedic problems, such as deformities of the hip, knee, ankle, or foot. I assume that you do not have any of these major deformities, but rather are talking about new knee pain that has developed recently. If this is the case, it is still possible that your knee pain might be related to your spinal bifida, especially if you have some weakness in the leg muscles, leading to imbalanced strain on the knees over the years.
I suggest that you discuss this issue with your
primary care doctor, if you have not done so already. If they find any evidence of a significant problem, they will likely want to refer you to an orthopedic specialist for more in depth evaluation.