Diagnostic dilemma: A woman heard a 'pop' during pilates class. Her spine had sprung a leak.

A top down image of a woman doing pilates on a reformer machine.

The patient: A 42-year-old woman in the United Kingdom

The symptoms: During a reformer pilates class — a type of pilates that incorporates machinery with springs that add resistance — the patient felt a "pop" in the left side of her neck. She developed a headache about an hour later. The pain lessened somewhat when she was lying down. But over the next several days, the headaches worsened, disrupting her daily activities.