NEW YORK (VINnews)  — A teenager in China who had just completed his national college entrance examinations found himself hospitalized in serious condition and unable to walk after spending weeks lying on the couch and in bed while using his mobile phone intensively.

According to reports in local media, the teenager spent more than five hours each day playing video games and browsing social media, often without getting up or engaging in even minimal physical activity.

After two weeks of almost complete inactivity, the teenager began experiencing severe pain, significant swelling, and extreme tenderness in his right calf. Eventually, even simple walking became impossible for him. His family initially believed he was suffering from ordinary muscle pain caused by prolonged sitting. However, as his condition rapidly deteriorated, they rushed him to a local hospital for urgent medical attention.

Following a comprehensive medical examination, doctors diagnosed the teenager with deep vein thrombosis (DVT), a serious condition in which a blood clot forms in a deep vein, most commonly in the leg.

Doctors explained that while the teenager may have had a genetic predisposition to excessive blood clotting, the main immediate trigger for the dangerous condition was his prolonged immobility and spending extended periods lying down in front of his phone.

The medical team issued a warning to the public, noting that common symptoms of DVT include unusual swelling in one leg, pain, a feeling of heaviness, redness, and localized warmth.

Doctors also stressed that additional symptoms such as shortness of breath, chest pain, or coughing up blood could indicate a potentially fatal pulmonary embolism. Such symptoms constitute a medical emergency and require immediate evaluation in an emergency department.