PTSD is a serious psychological/neurological condition caused by exposure to a traumatic event(s). It is treatable, and as other posters have said, it is amenable to treatment with a properly trained medical doctor and/or psychologist with a specific background in PTSD. Meditation and yoga have been found to be effective implements on a broader spectrum of treatments, that may involve Cognitive Behavioral Therapy, medication, MBSR, and other modalities. There are some new studies emerging that show effectiveness in using MDMA in tandem with medical supervision and cognitive therapy.
One site that is interesting is the work that Dr. Richie Davidson at Wisconsin-Madison is doing, involving meditation/MBSR with combat veterans https://vimeo.com/50520623
Dr. Davidson has been coordinating his research with HHDL's MInd and LIfe Institute. There appears to be a strong potential for Buddhist meditation to meet western psychology and medicine in this field of MBSR and PTSD therapies.
No one would recommend treating a broken leg with meditation or yoga, and the same is true of a damaged brain, hurt through trauma. You'd see a qualified doctor. The great news that Dr. Davidson is exploring is that the brain, like bones and tissue, has plasticity...it is malleable, fixable and it heals when proper therapy is given. The news re treatment of PTSD is getting better and brighter every day, but you'll need to connect with a trained clinician to tap into these treatments that are helping people and saving lives.