After total hip replacement surgery, is it normal for the operated leg to be a little bit longer than the good one?

Can be: While i wouldn't call it normal, leg lengthening is a potential result of total hip replacement and can be no big deal or a significant disability. Leg lengthening has become less common with newer implants and surgical techniques. Significant lengthening can be balanced with a heel lift in the other shoe.

Yes: During hip replacement surgery, the soft tissues around the hip are tightened by varying the length of the prosthesis. Although the restoration of equal length is desired, sometimes, a slight increase in length is necessary for stability. Your body is used to walking with flexed hip prior to the replacement surgery. This plus the loss of cartilage height can lead to a perception of a longer leg.

Normal? No.: As arthritis of the hip progresses, the joint collapses and the leg becomes slightly shorter. When hip replacement is performed, it is our goal to re-establish the 'normal' length of the leg, so the joint and muscles work best. If the other leg is 'good', then the lengths of the two legs should be equal after surgery. It may feel initially slightly longer, but should feel normal within 3-6 mos.