In Lost, what medical specialty did Jack Shephard practice?

Jack Shephard practiced spinal surgery in the TV series Lost.

Before Oceanic Flight 815 crashed, Jack worked as a spinal surgeon. His medical training made him the most obvious leader during the survivors’ first days on the island, when he treated wounds, performed emergency procedures, and organized efforts to find help.

Jack’s professional background is especially important because his father, Christian Shephard, was also a surgeon. Their difficult relationship forms a major part of Jack’s flashback story and helps explain Jack’s perfectionism, responsibility, and fear of failure.

The specialty is sometimes loosely described as neurosurgery because spinal surgery overlaps with neurological medicine. However, Lost identifies Jack specifically as a spinal surgeon. Matthew Fox played Jack, while his father Christian was portrayed by John Terry.