Can yoga reverse a hunchback? A viral New York Post article suggests that at least for one woman, the answer is yes. The story features 85-year-old Anna Pesce and the yoga instructor who helped her straighten up—literally—after decades with a painful, crippling back condition.

Pesce has osteoporosis and scoliosis, and both contributed to a spine curvature that left her largely confined to a wheelchair, with frequent shooting pains in her back.

After trying acupuncture, physical therapy, and chiropractic treatment—all of which she says provided only temporary relief—Pesce began taking private classes with New York City-based yoga instructor Rachel Jesien, the Post reports.

Jesien isn’t just any yoga instructor, though; she has scoliosis herself (a spinal curvature that can be diagnosed in childhood), and specializes in back care. And she gave Pesce a personalized plan of stretching and strengthening moves to help her heal.

After about a month, Pesce was able to stand straighter and walk again. Two years later, she’s doing modified headstands.

So is sun salutation really a cure? Pesce’s improvement speaks for itself—and the Post has the before-and-after pictures to prove it. But if you have back problems related to bone loss, is it really safe?

We spoke with Sherri Betz, a physical therapist and member of the National Osteoporosis Foundation’s Exercise and Rehabilitation Council, to get the scoop. Before rolling out your mat, here’s what you should know.

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Yoga can be great for osteoporosisor awful

“I generally have huge precautions for people who want to do yoga when they have osteoporosis because, ironically, it can be the best thing for you but it can also be the worst,” says Betz, who is also a certified yoga and Pilates instructor, but has not treated or worked with Pesce. The risks, she says, are because of poses that involve extreme bending or flexing. For someone with weakened bones, these moves can put them at risk of spinal fracture.

Even people with osteopenia—low bone mass that is often a precursor to osteoporosis—should be careful with yoga. In a 2012 case report, a Mayo Clinic researcher wrote about three people with osteopenia who developed yoga-induced back and neck pain or compression fractures.

“That being said, yoga—when practiced carefully—can be really great for osteoporosis,” Betz adds. It can help stretch and reduce the curvature of the spine, and build the strength needed to stand up straight. They key, she says, is to practice the right moves and stay away from the wrong ones.

Avoid rounding, twisting, and pushing too hard

Poses that cause the spine to round—like a full forward fold—are not recommended for people with osteoporosis, says Betz. “Even in the [New York Post] video where she’s sitting on the chair and rotating her foot, I wouldn’t allow that,” she says. “I’d have her sit up straight and not allow her spine to flex forward as much as possible.”

Deep twists, hip stretches, and side bends can also raise the risk of fracture, she says, as can any pose that an instructor forces you into. (That’s why it’s important to practice with someone who knows the risks involved, and to not push yourself too hard, either.)

Finally, she says, be careful about lying on your stomach on just a yoga mat on the hard floor. “It puts pressure on the rib cage and can actually cause rib fractures,” Betz says. Put a pillow under your upper body for support.

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Work on balance, leg strength, and back extensions instead

“All the standing poses—like Triangle, Warrior II, Warrior III, Half Moon pose—are great for someone who wants to improve their balance, leg strength, and back extensor strength,” Betz says. If you’re worried about balancing on one leg, she recommends holding onto a chair to modify poses.

Gentle back extensions, like Upward Dog, can also be enormously beneficial for someone with a curvature like Pesce’s, Betz says.

In fact, the entire Sun Salutation series of yoga poses can be safe, as long as you don’t round your spine while doing Downward Dog and or Forward Fold. (For the latter, she says, hinge at the hips and stop halfway, keeping your back as straight as possible.)

Yes, yoga can reverse a hunchback and treat back pain

But Pesce’s results aren’t typical. “This woman’s remarkable improvement is definitely impressive,” says Betz. Passive stretching—like laying backward over a bolster pillow—likely helped reverse the curve of her spine, she says, but that’s just part of it.

“Yoga also teaches cues for good posture, like rooting the feet and standing tall through the body,” she says. “That’s what’s helping to put her body in the right alignment and strengthen the muscles she needs to stay upright.”

As far as back pain goes, staying active has been shown to be one of the best treatments out there. And now that Pesce’s able to lengthen her spine and stand upright, she’s probably taking pressure off stressed joints and nerves, says Betz.

And there’s one more thing: “The weight of her head, when she’s bent over, is astronomical,” she adds. “She had to work very hard, in a not-so-healthy way, just to hold her head up. Once she straightens up, there’s a lot less strain there.”

Research supports the idea that yoga can help osteoporosis-related back problems. A 2009 study, for example, found that hour-long classes, three days a week for 24 weeks, helped reduce hyperkyphosis—the technical name for a hunchback or Dowager’s hump, the osteoporosis-related upper back curvature—with an average of 4.4% improvement in kyphosis angle.

However, Betz says, people whose conditions are as advanced as Pesce’s appeared to be don’t usually see such a night-and-day difference. “This kind of dramatic result is not usual,” she says.

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Finding the right instructor can be a challenge

Unfortunately, there is no independently verified certification program for yoga instructors who want to specialize in back care, says Betz. (Pesce’s instructor, Jesien, has a back care and scoliosis certificate from the Yoga Union Center in New York City.) 

“Physicians worry about recommending yoga to people with osteoporosis,” she says, “because they don’t know how to send them to someone who isn’t going to hurt them. There’s no safe referral source right now.”

Betz is working with the National Osteoporosis Foundation to change that, and hopes to launch a database of trained instructors in the future. Until then, she recommends seeing a physical therapist who can incorporate yoga into their sessions. (Find one who specializes in geriatrics or musculoskeletal issues at APTA.org.) 

The National Osteoporosis Foundation also has information about safe exercise and yoga dos and don’ts. The important thing, says Betz, is to keep moving. “We want to help people create an exercise program they enjoy that will be safe and effective in building bones,” she says, “and if they enjoy yoga, we don’t want to restrict that.”