Progesterone is one hormone used for treatment in research:
Wright, David W., et al. ProTECT: a randomized clinical trial of progesterone for acute traumatic brain injury. Annals of emergency medicine 49.4 (2007): 391-402.
https://doi.org/10.1016/j.annemergmed.2006.07.932
>However, moderate traumatic brain injury survivors who received progesterone were more likely to have a moderate to good outcome than those randomized to placebo.
This is a large review discussing the neuroprotective effects of progesterone:
Stein, Donald G. Progesterone exerts neuroprotective effects after brain injury. Brain research reviews 57.2 (2008): 386-397.
https://doi.org/10.1016/j.brainresrev.2007.06.012
The full text with their many references can be found here:
http://sci-hub.nu/10.1016/j.brainresrev.2007.06.012
I suppose it would be important to find out if progesterone needs to be administered immediately after the injury or if it can be effective much later. I haven't dug out that distinction, but it is safe. Both men and women make progesterone, so short term high dose progesterone as a therapy seems reasonable. I don't think there is much cause for concern about "feminization" unless done indefinitely, and can be balanced out by supplementation of other steroids either at a later date or at the same time.
Spritzer, Mark D., and Liisa AM Galea. Testosterone and dihydrotestosterone, but not estradiol, enhance survival of new hippocampal neurons in adult male rats. Developmental neurobiology 67.10 (2007): 1321-1333.
https://doi.org/10.1002/dneu.20457
However, there is a report of dihydrotestosterone (the primary androgen) being not so great in brain injury:
Cheng, Jian, Nabil J. Alkayed, and Patricia D. Hurn. Deleterious effects of dihydrotestosterone on cerebral ischemic injury. Journal of Cerebral Blood Flow & Metabolism 27.9 (2007): 1553-1562.
http://journals.sagepub.com/doi/abs/10.1038/sj.jcbfm.9600457
Progesterone has a lot of research behind it on this topic but other gonadal steroids not so much. Because boys make a higher ratio of progesterone before puberty* and the brain grows more in childhood, the temporary increase of progesterone could be somewhat like a return to childhood, which is good because the brain grows more during that time.
*This is a rumored claim I have heard. I could not find a single definitive study as progesterone is not observed frequently in males, but progesterone also converts to downstream hormones such as testosterone (You might expect that to happen more frequently in men.) and women transition to pseudo-men with androgens fairly easily, so androgens could simply be administered later if "feminization" is a concern.