The tibia was the larger of the two long bones in the lower leg.
In 2368, Alexander Rozhenko suffered a hairline fracture of the tibia after being injured in a fire in Biolab 4 on the USS Enterprise-D. (TNG: "New Ground")
In 2374, Kellin was left with a tibular compound fracture after a bulkhead on her ship had fallen on her. (VOY: "Unforgettable")