That seems pretty hard to believe knowing the modern medicine, especially since he played football after the operation? He was also training regularly, I am not sure why he didn't retire if that was the case instead of opting for continuing training and playing because the way it's described it's not going to magically appear again?
It could well be truth though, I am not saying you are lying or something like that, but I find it hard to believe.
https://www.90min.com/posts/man-utd...-hell-criticism-rio-ferdinand-losing-his-mind
"....However, the
meniscus was so badly damaged that the surgeon was forced to remove it altogether, meaning his bones would rub together inside the joint. That caused serious pain when making sideways movements, and the issue eventually caught up with Jones..."
What is the Meniscus?
The menisci are essential shock absorbers for the joint. They are also important for normal gait and stability of the knee.
Young athletes who have undergone a partial or full meniscectomy due to a meniscus injury or prior non-treated ACL tears have a very high chance of
developing osteoarthritis later in life, which has been found to be between 65% to 90% of the time.
"....
Osteoarthritis is a degenerative disease that worsens over time, often resulting in chronic pain.
Joint pain and stiffness can become severe enough to make daily tasks difficult. Depression and sleep disturbances can result from the pain and disability of osteoarthritis..."
https://www.mayoclinic.org/diseases-conditions/osteoarthritis/symptoms-causes/syc-20351925
For people with arthritis to aid walking, options range from custom shoes, to specially designed shoe inserts called orthotics, to braces, canes, crutches, and even walkers