If I may clarify, as some of the information above is incorrect:
In the US, most final year medical students apply directly to their specialty training without doing 1 or 2 house officer years first.
Most training programmes in the US are shorter than their equivalents in the UK and there is much more assurance that you will obtain your training postion and complete it.
Internship is the first year of
residency and you are paid for it. Thus, it is completed after graduation from medical school. Salaries will vary from program to program, but generally start in the high 30K/year USD to mid 40K and top out around $50 K USD/year or so. It would be highly unusual to make $60 K USD as a resident, at least in the shorter training programmes (I made $57K as a fellow). US residents are not paid overtime.
Recommendations are that residents not work more than 80 hrs per week, averaged over a month. That means you can work more than 80 hrs per week as long as another week you work less. However, bear in mind that many places violate these "rules" so you should expect to work at least 80 hrs per week, maybe more, and be pleasantly suprised if you work less.
Most US residency programs include the internship in the training scheme. There are some which require a "preliminary year" in general medicine or surgery or a "transitional year" (which is similar to the 3rd year of US medical school in that you do a variety of rotations - ie, OB, Surgery, Medicine, etc.). The programs which require a prelim or transitional year either offer them or you are required to apply for them separately. Most US residencies use a centralized matching service to match final year students with open positions they have interviewed for. More info is beyond the scope of this post but you can find more info at
http://www.nrmp.org or
http://www.sfmatch.org (for certain specialties).
Your time frame for training in the US is off a bit. Surgery is not 3 years in the US, but rather a minimum of 5 or up to 7 years (at some programs which require 1-2 years in a research lab) after medical school to complete the surgery residency requirements.
There are VERY FEW surgical programs which specialize right away; most commonly found are programs in Plastics and Reconstructive surgery some of which match right out of medical school for a program which is 5-6 years in length. For the first time this year, a very few (around 5 programs as I recall) Vascular Surgery programs matched final year students for a 3+3 program which refers to 3 years general surgery and 3 years vascular surgery. This cuts 1 year off the traditional 5+2 of 5 years general surgery and 2 years of Vascular surgery fellowship. Using your example of Thoracic surgery, at this time, you need to complete a general surgery residency after medical school (as above, 5-7 years) then apply for and complete a Thoracic surgery fellowship which are 2-3 years in length (so a minimum of 7 years after medical school).
Internal Medicine is usually 3 years after medical school, although some spend an additional year as Chief resident, for a total of 4 years. If you desire to pursue a subspecialty of internal medicine, such as gastroenterology, then as you noted, you would apply for fellowship training - which can last from 1-3 additional years depending on the field.
There are many, many other types of residencies which are not subspecialties of surgery or internal medicine and have their own specific programs, and application processes: Derm and Psych as you note (although both require a Preliminary medicine year), Radiation Oncology, Radiology, Anesthesiology, Family Medicine, Emergency Medicine, Physical Medicine and Rehab, etc. SDN has many forums which discuss these various fields ad we haven't covered them all.
See:
http://www.ama-assn.org/vapp/freida/spcstsc/0,1238,450,00.html for more information regarding specialty training in the US by field; bear in mind that some of the information contained on FREIDA is not updated or necessarily the latest word.
It is true that in the UK, students are given less clinical, hands-on, independent training than their counterparts in the US. You do NOT have to do a "foundation" year to be able to match into a US residency, but the additional clinical experience would be helpful. Most important is your USMLE scores (Step 1 is more important than Step 2) and having some US clinical experience. That said, there are lots of opportunities to do a final year medical school elective in the US which will familiarize yourself with the US medical process as well as allowing you to meet US medical faculty who could potentially write you letters of recommendation. Most FMGs who match into a US residency program have no clinical experience beyond medical school - again, it might help you when you start internship here, but is not necessary.
At any rate, bottom line is:
- US residencies are *generally* shorter than their UK counterparts because they do not require 1-2 house officer, or "foundation" years before starting the specialty training
- US residents make less money and work longer hours than their counterparts in the UK
- US medical students have more clinical, hands-on training than those in the UK, who generally pick up those skills during their foundation years
- if you are not a US citizen, you will be limited somewhat in which residency programs (not specialties) you are eligible for based on visa status
- depending on your visa status, you may have to return home for 2 years after completing US residency to satisfy visa requirements
- some US residencies are effectively off-limits for *most* who have not completed their medical school in the US; these are the most competitive residencies and include things like Plastics, Derm, Ortho, etc.
With regard to applying to US residencies as an FMG, be aware that although ECFMG or the NRMP does not require that you have ECFMG certificate in hand or even USMLE Step 2 completed to apply for residency, programs may have their own rules. Therefore, while pretty much all require that you submit a USMLE Step 1 score, letters of recommendation and a medical school transcript, bear in mind that some may not review your application without the completed ECFMG certificate (which you cannot get until you graduate, so this may require taking a year off between med school and applying for US residency) or at least USMLE Step 2.
Hope this helps...