What is Vanishing Bone Disease? Woman's Arm Disappears From X-Ray

3_6_Humerus Radius Ulna
This image shows a humerus and ulna meeting at the elbow. These bones were affected by the woman's vanishing bone disease. Brian C Goss/Wikimedia Commons/Public Domain

Doctors have been baffled by a series of radiographs showing the mysterious disappearance of a woman's arm bones over the course of more than a year.

Writing in BMJ Case Reports, doctors from the Royal Infirmary of Edinburgh in Scotland described the strange case, in which the previously healthy 44-year-old's left arm bones seemed to vanish before their eyes

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Radiographs of the woman's arm performed at presentation, 12 months later and 15 months later. At 15 months, the have faded noticeably. BMJ Case Reports

Increasing pain in her left shoulder was the first sign that something was wrong. Doctors performed an MRI and noticed a lesion in the woman's arm that they initially thought might be a sign of cancer. A biopsy, however, later showed her lesion was benign.

Instead, the team noted the lesion was consistent with a fracture following a minor fall. The fracture, it seemed, was a sign of underlying disease.

Blood Vessels Replace Disappearing Bone

A year later, the woman was still in pain with a swollen arm. Medical imaging revealed another fracture. It was then that doctors noted her humerus bone appeared faded on their images.

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More tests revealed that her initial lesion—made up of damaged blood vessels—had grown in size. The bone itself was being broken down far more extensively than normal. Bones constantly remodel to stay healthy, but in this case, the bone was disappearing much quicker than it was being replaced.

3_6_Humerus Radius Ulna
This image shows a humerus and ulna meeting at the elbow. These bones were affected by the woman's vanishing bone disease. Brian C Goss/Wikimedia Commons/Public Domain

Just one month later, radiographs showed the disease was spreading beyond the humerus bone, which had almost completely vanished. Blood and lymph vessels were slowly taking over the bones in the woman's arms: first the humerus, then the ulna in her forearm.

Perplexed by the bizarre results, the doctors sought a second opinion. Eventually, the woman was diagnosed with Gorham-Stout disease, also known as vanishing bone disease.

Incredibly Rare Disease

With Gorham-Stout disease, the bone is destroyed and replaced by intruding vessels. Although the disease is essentially benign, it can cause death and paralysis if it spreads to the vertebra.

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Incredibly rare and difficult to diagnose, just 64 cases of vanishing bone disease have been reported in scientific literature. Just like this woman, the first reported case occurred in the humerus, Radiopaedia reported. The disease, however, can affect any bone in people of any gender, at any age.

What causes the disease is a mystery, according to the National Organization for Rare Disorders (NORD). Surgeons often remove the affected areas of bone, and sometimes graft bone to encourage new bone formation. Doctors sometimes treat patients with radiation therapy and may prescribe drugs designed to prevent the loss of bone or stem the spread of vessels, NORD states.

"Ultimately, this is a challenging disease where evidence-based management remains lacking," the authors of the report concluded.