The surgeons kit above was fairly standard equipment for Civil War doctors. You can see there is not a lot there that is not made for cutting or sawing, that is mainly because that is what a doctor on the battlefield would do most, cut and saw.
It is estimated that over 60,000 battlefield surgeries were done during the war, and of those almost 45,000 were amputations. While it may seem extreme today at the time amputation was done to protect the patient against gangrene which was almost always life threatening. What made it worse was that there was really no anesthetic available, and even if the patient did survive the surgery, infection could always make the entire point moot. Needless to say amputation was something that many soldiers feared.
If whoever the amputation went well and the patient survived the recovery, there was a good chance they would be able to live a very productive life. Even though it was still not as advanced as today, prosthetics, artificial legs and even hands, were available to the men. In fact in the years between 1861 and 1873 over 150 patents were issued for artificial limbs. Both sides during and after the war provided funds to the veterans that needed these devices.
So for many the site of that kit in the photo above being brought out led to outright terror, for most of them it also meant a chance at life.