Dear Dr. Roach: On Nov. 2, 2020, I had a total right hip replacement. The surgery was successful, and the incision has healed completely. X-rays on the day of the surgery are clear. However, X-rays in April this year show something the surgeon called heterotopic ossification.

It feels as if there is something large growing inside my hip. How often does this type of thing occur, and is surgery necessary for treatment? — D.N.

Answer: “Heterotopic” is from the Greek roots meaning “another place,” while ossification refers to making bone. So, heterotopic ossification is a bone in a place it doesn’t belong.

The major cause of heterotopic ossification is trauma, and a hip replacement surgery is quite traumatic. The pieces of bone form in the soft tissues around the hip. Men are more likely to develop this than women, and different studies report from 53% up to 100% of people will develop some bone fragments, but only about 10% of people will develop large enough fragments to cause symptoms.

If the symptoms (usually pain and stiffness) become advanced, then, yes, surgery is usually required to remove the fragments.

Dear Dr. Roach: I take generic thyroid medication daily since my thyroidectomy. I get my levels checked every six months.

Unfortunately, I am changing to a new endocrinologist who does not feel the generics are as reliable as the name brand. The generic is $3 for 90 days, but the brand name costs $200 for 90 days. — M.K.

Answer: I agree with your endocrinologist that the brand-name Synthroid has better quality control than the generic manufacturers; however, that difference is now very small.

With some precautions, most people will do fine with generic versions of levothyroxine. I recommend patients discuss with their pharmacist how to get the same generic brand each time.

Most of the time, the pharmacist is able to do this, and the levels of the hormone in the blood are almost always very stable.