Does surgery correct the rotation of the spine? YES, IT DOES
There are some websites out there claiming to provide information about scoliosis and spinal fusion surgery, but they are providing outdated and incorrect info. I thought I'd write this just to reassure people who may have stumbled across such sites.
I've often seen it claimed that "surgery will not correct the rotation of the spine": this is incorrect. Years ago, the old Harrington Rod (which has been obsolete for many years) was not able to derotate the spine because it only attached to each end of the curve. However, today's pedicle screw systems attach to each separate vertebrae, and each one is gently derotated before being fused in place. Usually this will be enough to pull the ribs back into place and reduce the rib hump significantly, but if a large ribcage deformity remains then the surgeon may do a costoplasty procedure to correct it.
It has also been claimed that surgery will correct the spinal curvatures "by 50% at most". This is again inaccurate; it may have been the norm 20 or 30 years ago, but whilst today's surgeons tend to err on the side of caution with regards to the amount of correction they say they will be able to achieve, most people today find that their scoliosis is greatly reduced - very often to near enough normal degrees.
If you are considering surgery, it's a good idea to talk to your surgeon about the techniques that they use and the typical corrections that they achieve, and talk to others who have had surgery RECENTLY (rather than years ago - techniques have moved on!). Don't rely on websites which take their information from old, outdated sources, and be especially wary of unscrupulous alternative practitioners who publish scare stories and use data from decades ago to try to frighten people off surgery.
BTW I'm not vehemently pro-surgery, I'm just very keen on people having access to accurate information. Surgery is not always the best course of action for everyone.
37 years old, diagnosed with infantile idiopathic scoliosis at 6 months old with curves of 62(T) and 40(L) degrees. Casting and Milwaukee braces until surgery at 10 - ant release/pos fusion T1-T12, halo traction. Post op cast and then TLSO. Further surgery at 18 (ant release/pos fusion extended to L3 to include lumbar curve, costoplasty) and 25 (another costoplasty). Fusion extended to L4 at 33 (XLIF with 4 pedicle screws and two short rods). Pre-op curves: 76(T) and 70(L). Post-op curves: 45(T) and 35(L). Diagnosed with Ehlers-Danlos Syndrome aged 34; scoliosis almost certainly due to this rather than being idiopathic.