Like every other peptide/compound, each situation is relative.
However, IMO, it's always best to do separately.
Depending on how long your injuries existed, how serious the injuries were, where the injuries are located, how your body reacts to those injuries, genetics, your diet, your SLEEP (hugely important), your stress, how shitty your body was prior to taking peps....
If your injury or injuries lasted longer than 6 months, I would strongly recommend you take TB first, for 3 weeks. TB4 is the full chain that is stronger for more systemic/broader effects but has a much shorter half life and TB-500 is a partial chain that is more specific to the regional area and isn't as strong, but has a much longer half life. TB4 also costs considerably more than TB-500.
Then you take BPC-157 for the next 3 weeks.
Then you take both for the next 3 weeks.
By this time, most of your injuries should be 90% better. You'll still need to do some PT.
Then you take BPC-157 at maintenance dose for however long you want.
Just keep in mind that the more you take it long term (past 12 weeks), the higher chances of risk(s).