Patients sometimes wonder what the effect of a total joint replacement will be on their body weight. This small study from the Insall Scott Kelly Institute in New York City answered that question for 20 patients.
Body weight was measured before and after total knee replacement (TKR). The joint and bone removed was weighed and compared to the weight of the implant replacing the joint. Body weight was measured again one year later.
The authors report a zero percent weight gain. Men who received larger-sized implants had the most weight gain right after surgery. The increase translated to about three-fourths of a pound for men and slightly more than half a pound for women. The increase in weight was directly linked to the size of the implant.
The authors conclude that weight differences before and after TKR are so small as to be negligible.