Were your symptoms amplified by breathing deeply or by tilting your head/neck? I just wish I could understand the full anatomy of what was happening to me. If Rhomboid trigger points cause the pain in my upper back, and rhomboid trigger points are caused by poor posture, then why would I develop TOS at 17? why not when I was 15? My posture has been the exact same my entire life. Also, I work on my posture as much as possible and do all of my work at a standing desk, while also doing strengthening every other day for my back with a physio therapist. This is honestly the strangest condition ever, it's like it's resistant to change.