Here's the top 20 list, courtesy of the Agency for Healthcare Research and Quality:

1. Septicemia (except in labor) — $20.3 billion
2. Osteoarthritis — $14.8 billion
3. Complication of device, implant or graft — $12.9 billion
4. Liveborn (general childbirth) — $12.4 billion
5. Heart attack — $11.5 billion
6. Spondylosis, intervertebral disc disorders, other back problems — $11.2 billion
7. Pneumonia (except caused by tuberculosis and STDs) — $10.6 billion
8. Congestive heart failure — $10.5 billion
9. Coronary atherosclerosis — $10.4 billion
10. Adult respiratory failure — $8.7 billion
11. Acute cerebrovascular disease — $8.4 billion
12. Cardiac dysrhythmias — $7.6 billion
13. Complications of surgical procedures or medical care — $6.9 billion
14. Chronic obstructive pulmonary disease and bronchiectasis — $5.7 billion
15. Rehab care, fitting of prostheses and adjustment of devices — $5.5 billion
16. Diabetes mellitus with complications — $5.4 billion
17. Biliary tract disease — $5.1 billion
18. Hip fractures — $4.9 billion
19. Mood disorders — $4.8 billion
20. Acute and unspecified renal failure — $4.7 billion

The agency reported that total cost of hospital stays in 2011was $387 billion, and reported that Medicare and Medicaid paid 63 percent of that total, or $242.9 billion. Commercial insurers covered 29 percent, or $112.5 billion, while the remaining $17.1 billion was labeled "uninsured hospitalizations."