Skinny jeans are in fashion, and if worn the right way, can be both safe and slimming. Unfortunately for one 35-year-old woman who was helping her relative move out of her house, her skinny jeans left her helpless and on the floor by the end of the day. Australian researchers from the University of Adelaide published a case study after doctors examined the woman in hopes of revealing the damage skinny jeans can cause a person if not worn correctly.

The unnamed woman was unable to get up for hours after squatting over cardboard moving boxes. When she was found and rushed to the hospital, her feet were numb and her calves were so swollen they had to cut her out of them. The jeans had damaged muscle and nerve fibers in her lower legs as a result of the prolonged squatting. According to the doctors, her condition was worsened by the constrictive skinny jeans.

She was diagnosed with “compartment syndrome,” a condition that reduces the blood supply to the leg by cutting off nerves and swelling muscles. It took her four days before she was able to walk again without the help of an aide.

Skinny jeans were not initially received well by the public, and have gained and lost popularity in waves throughout history. But in the mid-2000s they took over the market. Hospitals have seen a variety of different medical conditions caused by skinny jeans over the years, though. In 1993, Dr, Octavio Bessa, then an internist from Stamford, Conn., dubbed these conditions “Tight Pants Syndrome.”

In the 20 years Bessa practiced, he saw an average of 20 to 25 patients every year reporting vague abdominal discomfort, chest pains, and heart burn. When examined, they seemed to be healthy until he took a look at their pant width compared to their abdominal girth. He said the phenomenon is a medical reality that’s caused needless medical expenses and preventable suffering to hundreds of patients.

Skinny jeans and other types of tight, restrictive clothing can also cause meralgia paresthetica, which is characterized by tingling, numbness, and burning pain along the outer thigh. It occurs when the nerves that extend from the spinal column to the thigh are damaged from chronic compression—a situation easily caused by wearing jeans that are just too tight. Fashion doesn’t have to hurt. In most cases, just walk it off. The condition can be relieved by changing into looser clothing, according to the Mayo Clinic. However, in other severe-but-rare cases, medications and surgery may be necessary.

Source: Wai K, Thompson PD, and Kimber TE. Fashion victim: rhabdomyolysis and bilateral peroneal and tibial neuropathies as a result of squatting in ‘skinny jeans.’ Journal of Neurology Neurosurgery & Psychiatry. 2015.