In House M.D., which medical condition caused Dr. House’s chronic leg pain?

In House M.D., a muscle infarction caused Dr. House’s chronic leg pain.

Before the series begins, House suffers an infarction in the quadriceps muscle of his right thigh. The loss of blood flow damages the muscle, leaving him with permanent impairment and severe chronic pain. Doctors initially consider amputation, but House chooses a procedure that removes dead tissue while preserving the leg.

The injury explains House’s limp, his cane, and his dependence on pain medication. It also becomes a major part of his psychological and medical storyline because pain relief repeatedly competes with the consequences of addiction.

The condition is sometimes incorrectly described as a blood clot in the leg or simply as a heart attack. A muscle infarction is tissue death caused by inadequate blood supply; in House’s case, it occurs in skeletal muscle rather than the heart. The show’s backstory links the injury to an aneurysm and delayed recognition of the underlying problem.