This answer doesn’t give a full list of tests, and it’s better to say so than to put one together.
What you can expect is assessment rather than lab work. At a wound care center, the team will examine and measure your wound, check the blood flow in the area around the wound, determine why it is not healing, and create a treatment plan.
Checking the blood flow is the one worth knowing about in advance. It is the part people don’t expect, and so much follows from it. Whether a leg wound is treated with compression or protected from it, for instance, turns on what the circulation is doing.
Measurement is also more deliberate than it sounds. A wound that is measured at each visit is being tracked against itself. That is how a clinic tells whether a plan is working.
If you have debridement, the wound is probed to see how deep it is. With a foot ulcer, it is probed with a metal instrument to see how deep it is and to see if there is any foreign material or an object in the ulcer. That is done as part of the procedure rather than as a separate test.
If you have diabetes, two specific checks are part of regular care rather than something particular to a wound clinic: your provider should check your sensation with a tool called a monofilament, and your foot pulses will also be checked.
Individual clinics may do more. If you have been told a particular test is being arranged, the person arranging it is the one who can explain what it is looking for, and that’s a fair question to ask.