Journal de la colonne vertébrale

A Minimum of Two Years Results of Magnetically Controlled Growing Rods for Early Onset Scoliosis

Abstract

Burstein J, Rupprecht M, Kunkel P, Spiro AS, Hagemann C, Vettorazzi E, Stücker R and Ridderbusch K

Objectives: To determine mid-term results and complications of a single center on magnetically controlled growing rod (MCGR) technique in Early Onset Scoliosis (EOS). Recently a number of preliminary reports about safety and effectiveness of MCGR have been published. We present a minimum of two years follow up of the MCGR treatment. All patients were treated in one center with the same protocol.

Methods: 22 patients with EOS of different etiologies underwent primary surgical treatment with MCGR in double rod technique. There were 15 female and 7 male patients. Average age at surgery was 8.8 (range 4.6-14.3). Mean follow-up was 31 (24-46) months. Cobb angle changes, T1-T12 and T1-S1 length were calculated. Results were analyzed to measure correction of spinal deformity and gain in spinal length.

Results: The mean preoperative curve measured 61° (40-96) and improved to 28° (11-53) (p<0.001) after surgery. At follow-up the Cobb angle was further reduced to 26° (11-64) (p=0.54). The T1-T12- as well as the T1-S1- length increased significantly (p<0.001). The average preoperative thoracic kyphosis decreased from 44° (-32-86) to 28° (9-50) after surgery, respectively to 35° (8-62) at time of FU. Four patients developed a junctional kyphosis. Three of them had to be revised. One patient developed a lumbar “adding on”, one patient a deep wound infection and in another patient a screw pullout occurred that all required revision.

Conclusion: The study supports that the MCGR is an efficient and safe technique to treat EOS. Morbidity and complications are less than treatment with conventional GR´s. After 2 years transcutaneous lengthening is still possible without loss of correction and autofusion has not yet been detected.