A common method for removing extra fingers from newborns might cause the babies substantial pain and should be tossed out in favor of surgery, according to a new study.

That common procedure is known as suture ligation and involves tying thread around the unnecessary digits to cut off their blood flow, causing the tissue on the isolated side of the thread to die and fall off. Although it is the usual technique for removing excess fingers, it can come with complications like infections and can leave behind small amounts of tissue.

A team of doctors reported a case study in the Journal of the American Osteopathic Association in which a baby was born with an extra little finger on both his hands, known as postaxial polydactyly. The child had the type B version of this condition, in which the excess fingers are not well developed.

Those undeveloped digits might be as simple as bumps that are shaped like fingers.

“The mother reported that she was born with the same condition and underwent suture ligation as a newborn,” the authors explained. The procedure left her with a tiny amount of extra tissue on her hands, “which she denied as bothering her cosmetically or physically.”

Polydactyly, which can also occur on the feet, is found in one of roughly 1,000 babies, although the number for African-Americans is significantly higher — about six times more likely.

Another condition, syndactyly, is when a baby is born with webbed fingers or toes and adactyly is when fingers or toes are missing at birth.

According to the U.S. National Institutes of Health, polydactyly is the most common birth defect related to hands and feet and, while it is sometimes found with other birth abnormalities, it can also be found in babies who are otherwise completely healthy, both physically and intellectually.

The infant described in this case study, who was black, underwent the same procedure his mother once had when he was four days old. The doctors say the sixth finger on the left hand experienced tissue death within a week, but the right side needed to be tied off again for the same effect. After these two attempts, he was left with a similar amount of extra tissue as his mother at the end of the process.

“Although suture ligation has been touted as simple, safe, and effective, limited evidence shows that it can lead to a greater likelihood of incomplete amputation than surgical excision,” the study says. “Furthermore, suture ligation may be more likely to lead to painful neuromas than surgical excision. … These unsatisfactory outcomes affect quality of life and require additional, more elaborate procedures to resolve.”

A neuroma refers to a growth of nerve tissue that can come with significant discomfort, including pain, a burning sensation or numbness.

The authors write in their study that, in comparison the suture ligation, surgically removing tissue to get rid of an extra finger or toe is less likely to come with complications or to leave behind a trace of the excised digit. They also call for more research into methods for removing extra fingers and toes.