What is the name of Gregory House’s damaged leg muscle in House M.D.?

Gregory House’s chronic leg injury in House M.D. involves his quadriceps muscle.

The quadriceps is a group of four muscles on the front of the thigh that extends the knee. In House’s backstory, an infarction cuts off blood supply to part of the quadriceps, causing tissue death and leaving him with permanent pain and a limp.

The injury explains several recurring details: House uses a cane, takes pain medication, and walks with a distinctive gait. The show presents the infarction as a consequence of a misdiagnosed vascular problem, although the exact medical storytelling is dramatized for television.

Viewers sometimes identify the damaged area as the calf because House limps, but the relevant muscle is the quadriceps in the thigh. It is also not the same as a simple fracture or a routine knee injury.