OpinionFebruary 18, 20254 min readBroken Legs and Ankles Heal Better If You Walk on Them within WeeksUsing crutches for months is largely a thing of the past. Early weight-bearing has real benefitsBy Lydia Denworth edited by Josh Fischman Jay BendtTwenty years ago my husband, Mark, broke his left ankle and was in a cast and on crutches for nearly two months. Last year he broke the other ankle. But this time, after surgery, his doctor surprised us by instructing Mark to walk on it two weeks later.It turns out the standard advice to stay off a broken leg bone for at least six weeks is based less on scientific evidence and more on cultural cautionphysicians like to play it safe. But now studies show that complications are no more likely with early weight-bearing than with a long delay. Except in a few complex cases, walking around earlier helps broken bones heal, and it improves quality of life: for example, people can return to work and other activities faster.If you are fully immobilized, you come out of the cast with a sort of hairy, withered leg that takes forever to overcome, says orthopedic trauma surgeon Alex Trompeter of St. Georges University of London. The science tells us that the rate at which you lose muscle mass is far faster than the rate at which you gain it. Youre slow to build bone, too. Consider astronauts. After six months in zero gravity at the International Space Station, they lose 10 percent of their bone density, and to ward off that loss they do exercises in space that are equivalent to bearing weight.On supporting science journalismIf you're enjoying this article, consider supporting our award-winning journalism by subscribing. By purchasing a subscription you are helping to ensure the future of impactful stories about the discoveries and ideas shaping our world today.In the 19th century German surgeon and anatomist Julius Wolff recognized that healthy bones adapt and change in response to the load placed on them. That is why everyonebut especially women, who are more susceptible than men to osteoporosisshould lift weights as they age. It increases bone density.Those who walked early on femurs that had broken just above the knee had no higher rate of complications than those who stayed off the leg for six weeks.When you fracture a bone anywhere in the body, physicians first worry about stability. How much will the bone fragments move if you put weight on them? If the answer is too much, surgery is usually indicatedfirst a reduction to realign the pieces of bone and then fixation to hold them in place with screws, plates or rods.That procedure sets up a bone, which is living tissue, to heal naturally by making new bone and resorbing damaged cells. In the gap caused by a fracture, a healing tissue called callus forms first, which then turns into bone. The right amount of load or movement (heres where Wolffs discovery applies) is critical to this process. Too little results in no callus; too much prevents the bone from knitting back together. Its all about the strain environment, says orthopedic surgeon Chris Bretherton of Queen Marys Hospital in London.Surgical implants hold the alignment until that process is complete. Its a little bit of a race postoperatively between the bone healing and the fixation breaking, says orthopedic trauma surgeon Marilyn Heng of the University of Miami Miller School of Medicine. In that contest, she roots for the new bone. Once the body heals and forms bone across the fracture site, the hardware we put in becomes extraneous. The crux of our decisions for weight-bearing status is we want to win that race.And putting some load on the bones aids that goal. Although the process of bone healing is the same all over the body, bones in the lower limbs such as hips, femurs and ankles bring extra complications because they affect the ability to walk. In patients with hip fracturespredominantly frail, older peoplethat immobility can lead to dire consequences.Some patients do not have the dexterity and strength to manage partial weight-bearing while using crutches, so they stay in bed. The lack of movement leads to serious problems such as blood clots and weakening of the lungs. One 2005 study found that nine percent of hip fracture patients died within 30 days of breaking a hip and that 30 percent died within the first year. But more recent studies of healing hips suggest that early weight-bearing decreases mortality rates, and doctors have altered their practices. The normal standard of care is [now] to fix it and let people walk, Trompeter says.Breaks in long bones, like the femur in your thigh, can be relatively straightforward to repair with a rod. In a study that looked back at outcomes for a series of patients, Heng and her colleagues showed that those who walked early on femurs that had broken just above the knee had no higher rate of complications than those who stayed off the leg for six weeks.For ankles, the largest randomized controlled trial to date (480 fracture cases across 23 centers in the U.K.) was published in 2024 in the Lancet. Half of the patients were instructed to walk after two weeks, and the other half were told to wait until after six weeks. Any complications, such as infections or broken plates, were equally common in both groups, so early walking didnt pose a greater risk. And the early weight-bearing group reported better function in the ankle at six weeks and at four months postsurgery. Surgeons just needed a push, says Bretherton, who led the study. He hopes this evidence gives them that confidence.As for my husband, he jumped at the chance to get moving sooner. In less than two months, the point at which he was just coming out of a cast last time, his scar was fully healed, he was walking normally and, with a few limitationsno running, no quick pivotshe was exercising again. It seems that he won this race.This is an opinion and analysis article, and the views expressed by the author or authors are not necessarily those of Scientific American.