Medicare beneficiaries undergoing hip replacement surgeries can expect to remain in the hospital for less time but are more likely to be readmitted to the hospital or discharged to a rehabilitation facility than they were 20 years ago, new research finds.

Investigators at the University of Iowa compared Medicare data of hip replacement surgeries of beneficiaries collected from 1991 to 1992 to data collected from 2007 to 2008. Twenty years ago, the average length of stay in a hospital following hip surgery was nine days, whereas now it can be less than four days. But the proportion of patients discharged to skilled or post-acute care facilities has increased from 18% to 34%.

The researchers said the study reflects the complicated issues around healthcare costs, specifically when taking into account discharge rates to rehab facilities.

“You’re really just squeezing a balloon here. If we reduce the length of stay in the hospital, we can save money, or at least it seems like a way to save money. But, when we squeeze the balloon on one end to reduce length of stay, other costs pop up on the other side of the balloon,” lead study author Peter Cram, M.D., told HealthDay News.

The study was published in Wednesday’s issue of the Journal of the American Medical Association.