Temporary treatment with magnetically controlled growing rod for surgical correction of severe adolescent idiopathic thoracic scoliosis greater than 100°.

Introduction: Correction of severe idiopathic scoliosis poses surgical challenges. Treatment options entail anterior and/or posterior release, Halo-gravity traction (HGT) and three-column osteotomies (3CO). The authors report results with a novel technique of temporary short-term magnetically controlled growing rod (MCGR) as part of a posterior-only strategy to treat severe idiopathic major thoracic curves (MTC).
Methods: Seven patients with MTC > 100° treated with temporary MCGR were included. Mean age was 15 years. Preoperative MTC was av. 118° and TC-flexibility av. 19.8%. Patients underwent posterior instrumentation, periapical release using advanced Ponte osteotomies, segmental insertion of pedicle screws and a single MCGR. After av. 14 days, the second surgery was performed with removal of MCGR and final correction and fusion. The spinal height from lowest instrumented vertebra (LIV) to T1 was measured. MTC-correction and scoliosis correction index (SCI) were calculated.
Results: No patient suffered a major complication or neurologic deficit. Instrumentation was from T2 to L3 or L4. This kind of staged surgery achieved a correction of postop MTC to av. 39°, MTC-correction 67% and SCI of av. 4.3. Spinal height T1-LIV increased from preoperative av. 288 mm to postoperative av. 395 mm indicating an increase of > 10 cm.
Conclusion: This is the first series of AIS patients that had temporary MCGR to treat severe thoracic scoliosis. A staged protocol including internal temporary distraction with MCGR after posterior release and definitive correction resulted in large MTC-correction and restoration of trunk height. Results indicate that technique has the potential to reduce the necessity for HGT and high-risk 3CO for the correction of severe scoliosis.