55 degree scoliosis
is concerning. you still in growing phase. How about menstrual periods? you tend to grow 1.5 to2 years after the starting of the monthly periods. We also see riser sign an indicator of the skeletal maturity.
In your case, sciliosis is due to uneven growth of the spine with more growth on the side of hemivertebra. Traction and exercise may not reduce or halt the progression.
From my opinion you need a spinal fusion surgery
with partial correction of the curve. Thanks.