Knee Osteoarthritis (OA) is a major cause of disability and a common reason that people stop daily exercise. The estimated incidence of knee OA is 22.9% over the age of 40. The 2020 worldwide incidence of knee OA is estimated to be between 565.6 and 745.6 million individuals over the age of 40. Its incidence increases with weight and age and is associated with prior injury.
In a series of three studies, 9,683 knees (in 5,774 patients) were assessed for joint damage and osteoarthritis at baseline and 6,074 knees (in 3,988 individuals) for progression of their knee OA.
The knees were x-rayed and assessed at baseline and again four or five years later. Changes that the researchers were looking for were joint space narrowing as well as osteophytes and these changes were correlated against changes in BMI.
Unfortunately, as we and our patients all too well know, as knee osteoarthritis and pain worsen, the next stage is total knee replacement.
Th important finding and takeaway message from these studies was that for every | unit decrease in BMI (about 5 Ibs) was associated with an additional 4.76% reduction in the incidence and progression of the bone defects in knee OA.