(See also the eMedicine article Osteoarthritis
in the Physical Medicine and
Rehabilitation section.) Although the prevalence of Baker cysts in patients with inflammatory arthritis is higher than in patients with osteoarthritis, osteoarthritis is much more common than inflammatory arthritis. Using ultrasonography, Fam and colleagues found that 21 of 50 patients (42%) with osteoarthritis had Baker cysts.5 Bilateral cysts were seen in 8 patients (16%).