In House M.D., which fictional disease does House initially claim his leg pain is caused by?

In House M.D., House's leg pain is caused by a quadriceps infarction. The infarction is a loss of blood supply to muscle tissue in his right thigh, leaving him with chronic pain and a limp.

The injury is central to House's backstory. He initially experiences severe pain after the infarction, and delayed treatment contributes to permanent muscle damage. A later surgical procedure removes dead tissue, but it does not restore normal function. House therefore relies on a cane and takes pain medication, especially Vicodin.

Viewers sometimes describe the condition as a heart attack because the word “infarction” is associated with the heart. In this story, however, the affected tissue is the quadriceps muscle. A femoral fracture, tendon injury, or hip infection would be a different diagnosis and does not explain the canonical backstory.

House's physical disability is not merely a visual trait. It affects how he moves through the hospital and influences his relationship with pain, dependence, and medical authority. The injury also helps explain why he approaches symptoms with unusual personal intensity.