There are two cushion like structures between the bones called the meniscus. The bone inside the joint is covered by a smooth lining called the cartilage. Injury to either the ligaments, meniscus or cartilage can cause progressive damage to the joint. This leads to mal-alignment, i.e., the knee becomes bow shaped and bends inwards(varus) or outwards (valgus). Knee preservation involves correcting the alignment to get a straight leg and also to treat the ligament, meniscus or cartilage injury by arthroscopy. The operation to straighten the leg is called an ‘osteotomy’. Dr. Shekhar has been trained in osteotomy surgery for Dr. Ronald van Heerwaarden from Netherlands, a world leader in this operation. Osteotomy basically involves making a cut in the bone to straighten the leg and fixing the bone with titanium plate and screws. It is meant for patients who are either too young for a knee replacement, or do not want a replacement but wish to have pain relief and a straight leg.