OATS procedure is indicated for defects of what size?

OATS procedure is indicated for defects of what size?

• A. 0.5 square cm
• B. 1.0 square cm
• C. 2.0 square cm
• D. 1.5 square cm

Answer: (D)

OATS is used for restoring a focal, full-thickness cartilage defect with osteochondral plugs, so the size of the defect matters because it determines how many plugs you can harvest and how well you can recreate a smooth joint surface without overloading the donor site. The most appropriate indication is a defect around 1.5 cm2 because it is large enough to require an autograft mosaic of plugs to fill the area, yet small enough to cover with a manageable number of plugs and minimize donor-site morbidity. Very small defects (around 0.5 cm2) are typically treated with less invasive methods like debridement or microfracture, while larger defects (such as 2.0 cm2) pose greater challenges in achieving congruence and may push practitioners toward alternative options. Thus, 1.5 square centimeters is the best-fit size for this procedure.