Hi Aura
Few years ago I trained with a Wado 2nd DAN lady who dabbled in aikido from Eastwood Notts, who had a similar problem with curvature of the spine ''sorry cannot remember the correct term for her condition''
But she found Karate, Aikido to much for the lumbar region after a while.
Similar to this I have a student who has been diagnosed with ankylosing spondylitis
he also suffers curvature of the spine and rounding of the shulders.
You probably do the required swimming and other exercises your doctor or consultant has prescribed to take strain from the spine.
I agree with Lesley try a Tai Chi class or a system that has a basis that uses posture
for the least generation of movement for the power system.
To me simplicity is the key to all;
We are aware this is may not easy due to the fact ''we all like to get dirty hands so to speak''
Yet we have had some success with the ERGONOMICS of both these students. By this process of the posture to promote compensation to body weakness.
I suffer from Fibromialgia (This was through over training the body in power lifting in my younger years)so i have found ways to compensate for the condition through my martial arts training.
''I feel happy that I have found my little niche''
Hope you find what you are really looking for
Best Regards
Pike