I used to think that ballerinas’ feet must be dainty and beautiful. How else could they move so gracefully?

But the reality is that ballet dancers suffer for their art. Literally. Between the many hours of daily practice, rehearsals, and performances, up to 90% of dancers suffer injuries. For females, dancing en pointe (on the tips of their toes) can cause severe damage; men often get hurt when landing after a leap.

To stay in shape, professional dancers generally take a class five days a week. The last 15-20 minutes typically involve jumps. Here are dancers from the Pacific Northwest Ballet in class:

Millicent Powers, Chair of the Board of Trustees of Silicon Valley Ballet, says, “Dancers’ bones and bodies frequently exhibit signs of premature aging: bunions, bone deformations and tendons that are missing, damaged or otherwise impaired.”

Dancer Dane Youssef explains, “In nearly any other sport, one is allowed to wear shoes that are stuffed to the brim with nice comfy padding. In ballet, traditionally—the feet have to totally absorb the brunt of the shock…I’ve heard of lot of ballerinas who have to switch majors when they break their feet.”

Some common afflictions of dancers:

• Achilles Tendonitis—inflamation of the long tendon on the back of the leg
• Ankle Sprain
• Blisters—caused by rubbing of the shoes
• Bruised and broken nails
• Bunions—a deformity of the bone that causes the big toe to lean in towards the other toes
• Dancer’s Fracture—a break of the long bone on the outside of the foot; typically occurs after the dancer performs a jump
• Dancer’s Heel—Posterior Impingement Syndrome—a bump caused by wear-and-tear which forms on the back of the ballet dancer’s ankle, preventing her from dancing en pointe
• Hammertoe—misalignment of toe (usually the second one) so that it bends toward the big toe and looks like a hammerhead; often genetic, it may develop in dancers as a result of tearing of the ligaments on the bottom of the toes
• Heel Spur—an abnormal growth on the bottom of the heel bone
• Ingrown Toenail—painful condition in which the skin grows over the toenail; untreated, can lead to an infection
• Metatarsalgia—pain on the ball of the foot, which bear the brunt of “pushing off”; named for the five metatarsal bones
• Neuroma—a pinched nerve causes burning pain in the forefoot and numbness in the toes
• Plantar Fasciitis–irritation and inflammation of the fascial covering of the sole of the foot
• Sesamoiditis (Turf Toe Injuries)—inflammation of the two sesamoid bones in the forefoot causes pain underneath the big toe, like the sensation of walking on rocks
• Shin Splints—pain and swelling in the front or inside of the shin, indicating that the lining of the bone has torn away; can also indicate chronic exertional compartment syndrome, where pressure builds inside the muscles
• Stress fracture

While the ballet movements themselves tend to have the most noticeable detrimental effects on a dancer’s feet, ill-fitting shoes can also be the cause of foot pain. Calluses, fractures and ingrown toenails can form very quickly if dancers wear unsuitable shoes.

Toe shoes, worn by ballerinas dancing en pointe, have a hard base made up of layers of paper, leather, or burlap, and must be padded to adequately support and cushion the dancer’s foot. Professional dancers can wear out two to six pairs of toe shoes per week, at $70 or more per pair. The New York City Ballet spends $600,000 per year on toe shoes.

Dancers with the best chance of avoiding injury while performing en pointe tend to have toes all about the same length and strong ankles. “Pointe can jam the joints of the toes and feet,” says Dr. Brett Fried of South Florida Foot & Ankle Centers. “I would limit pointe, especially in pediatric patients.”

For more about the effects of dancing en pointe, see the following articles:

• From theguardian
• From Quora
• From wiseGEEK
• From Dance Direct

The next time you see a ballerina (seemingly) effortlessly pirouetting across the stage, appreciate that those moments of sheer beauty have a cost—literally, blood, sweat, tears, and pain.