Are there any alternative ways to treat scoliosis?

Yes. Scoliosis can be "treated" with medications, exercise, physical therapy, chiropractic treatment, and occasionally steroid injections to help relieve the symptoms of back pain and/or lower extremity pain. However these alternative treatments will not correct the spinal curvature. Bracing can help prevent worsening of scoliosis in certain cases but only surgery can correct the curve.
No. Only treatments known to help: bracing during growth stage if scoliosis determined to be at risk for progression or surgery for curve that failed bracing & reached 50 degrees or was large enough to be indicated for surgery & bracing at that point would be futile. However, avoiding bone density loss & obesity as well as doing regular exercise will otherwise help maintain a good back. No smoking!