Next generation of growth-sparing techniques: preliminary clinical results of a magnetically controlled growing rod in 14 patients

Session 3A - Early Onset Scoliosis: Paper no. 33SUMMARY: Growth-sparing techniques are commonly used for the treatment of progressive EOS. The standard growing rod (GR) technique requires multiple surgeries for lengthening. The preliminary results of MCGR has shown the comparable outcomes to standard GR without the need for repeated surgery which can be expected to reduce the overall complication rate in GR surgery. INTRODUCTION: The growing rod (GR) technique for management of progressive Early-Onset Scoliosis (EOS) is a viable alternative but with a high complication rate attributed to frequent surgical lengthenings. The safety and efficacy of a non-invasive Magnetically Controlled Growing Rod (MCGR) has been previously reported in a porcine model. We are reporting the preliminary results of this technique in EOS. METHODS: Retrospective review of prospectively collected multi-center data. Only patients who underwent MCGR surgery and at least 3 subsequent spinal distractions were included in this preliminary review. Distractions were performed in clinic without anesthesia or analgesics. T1-T12 and T1-S1 height and the distraction distance inside the actuator were analyzed in addition to conventional clinical and radiographic data. RESULTS: Patients (N=14; 7 F and 7 M) had a mean age of 8y+10m (3y+6m to 12y+7m) and underwent a total of 14 index surgeries (SR: index single rod in 5 and DR: dual rod in 9) and 91 distractions. There were 5 idiopathic, 4 neuromuscular, 2 congenital, 2 syndromic and one NF. Mean follow-up (FU) was 10 months (5.8-18.2). Mean Cobb changed from 57° pre-op to 35° post-op and correction was maintained (35°) at latest FU. T1-T12 increased by 4 mm for SR and 10 mm for DR with mean monthly gain of 0.5 and 1.39, respectively. T1-S1 gain was 4 mm for SR and 17 mm for DR with mean monthly gain of 0.5 mm for SR and 2.35 mm for DR. The mean interval between index surgery and the first distraction was 66 days and thereafter was 43 days. Complications included one superficial infection in (SR), one prominent implant (DR) and minimal loss of initial distraction in three after index MCGR (all SR). Overall, partial loss of distraction was observed following 14 of the 91 distractions (one DR and 13 SR). This loss was regained in subsequent distractions. There was no neurologic deficit or implant failure. CONCLUSION: MCGR appears to be safe and provided adequate distraction similar to the standard GR technique without the need for repeated surgeries. DR patients had better initial curve correction and greater spinal height. No major complications were observed during the short follow-up period. The FDA has not cleared the drug and/or medical device for the use described in this presentation (i.e., the drug or medical device is being discussed for an ‘off label’ use).postprin

Next generation of growth-sparing techniques: preliminary clinical results of a magnetically controlled growing rod in 14 patients

Concurrent Session 4B: Innovatiove Methods - Paper no. 75SUMMARY: Growth-sparing techniques are commonly used for the treatment of progressive EOS. The standard growing rod (GR) technique requires multiple surgeries for lengthening. The preliminary results of MCGR has shown the comparable outcomes to standard GR without the need for repeated surgery which can be expected to reduce the overall complication rate in GR surgery. INTRODUCTION: Growing rod technique (GR) has been a viable alternative for the treatment of progressive early onset scoliosis (EOS). However, a high complication rate associated with GR has been attributed to frequent surgeries required for lengthening. The safety and efficacy of a non-invasive Magnetically Controlled Growing Rod (MCGR) has been previously reported in a porcine model. We are reporting the preliminary clinical results of the use of this device. METHODS: Multicenter prospective review of early clinical and radiographic data of EOS patients underwent MCGR surgery. Patients who had at least 3 distractions were included. The technique was not significantly different from standard GR surgery. Distractions were performed in clinic without anesthesia or analgesics. The “Target” length (the intended distraction amount in mm which is set on the external magnet) and “Achieved” length (The distraction measured in mm on post distraction radiograph) were also recorded for each distraction. RESULTS: Patients (N=14, F=7,M=7) had mean age of 8y10m (3y6m to 12y7m) and underwent 14 index surgeries, single rod (SR) in 5, dual rod (DR) in 9 and 68 distractions. Diagnosis was idiopathic 5, neuromuscular 4, congenital 2, syndromic 2 and NF one. Mean FU was 9 months (4-15). Average distraction achieved was 4.2 mm per patient. The average time between index surgery and the first distraction was 66 days (28-185) and thereafter was 43 days (23-184). Complications included superficial infection in 1 (SR), prominent implant in 1 (DR) and minimal loss of initial length in 3 (21%) index surgery (all SR). Partial loss of distraction was observed following 14 of the 68 distractions (1 in DR,13 SR). This loss was regained in subsequent distractions. There was no neurologic deficit or implant failure. CONCLUSION: Preliminary results indicate that MCGR appears to be safe and provided the distraction comparable with standard GR procedure without the need for repeated surgeries. No major complications have been observed in the short follow up period …link_to_OA_fulltextThe 18th International Meeting on Advanced Spine Techniques (IMAST), Copenhagen, Denmark, 13-16 July 2011. In Final Program of 18th IMAST, 2011, p. 93-94, Paper no. 7

Next generation of growth-sparing techniques: preliminary clinical results of a magnetically controlled growing rod in 14 patients

Concurrent Session 4B: Innovatiove Methods - Paper no. 75SUMMARY: Growth-sparing techniques are commonly used for the treatment of progressive EOS. The standard growing rod (GR) technique requires multiple surgeries for lengthening. The preliminary results of MCGR has shown the comparable outcomes to standard GR without the need for repeated surgery which can be expected to reduce the overall complication rate in GR surgery. INTRODUCTION: Growing rod technique (GR) has been a viable alternative for the treatment of progressive early onset scoliosis (EOS). However, a high complication rate associated with GR has been attributed to frequent surgeries required for lengthening. The safety and efficacy of a non-invasive Magnetically Controlled Growing Rod (MCGR) has been previously reported in a porcine model. We are reporting the preliminary clinical results of the use of this device. METHODS: Multicenter prospective review of early clinical and radiographic data of EOS patients underwent MCGR surgery. Patients who had at least 3 distractions were included. The technique was not significantly different from standard GR surgery. Distractions were performed in clinic without anesthesia or analgesics. The “Target” length (the intended distraction amount in mm which is set on the external magnet) and “Achieved” length (The distraction measured in mm on post distraction radiograph) were also recorded for each distraction. RESULTS: Patients (N=14, F=7,M=7) had mean age of 8y10m (3y6m to 12y7m) and underwent 14 index surgeries, single rod (SR) in 5, dual rod (DR) in 9 and 68 distractions. Diagnosis was idiopathic 5, neuromuscular 4, congenital 2, syndromic 2 and NF one. Mean FU was 9 months (4-15). Average distraction achieved was 4.2 mm per patient. The average time between index surgery and the first distraction was 66 days (28-185) and thereafter was 43 days (23-184). Complications included superficial infection in 1 (SR), prominent implant in 1 (DR) and minimal loss of initial length in 3 (21%) index surgery (all SR). Partial loss of distraction was observed following 14 of the 68 distractions (1 in DR,13 SR). This loss was regained in subsequent distractions. There was no neurologic deficit or implant failure. CONCLUSION: Preliminary results indicate that MCGR appears to be safe and provided the distraction comparable with standard GR procedure without the need for repeated surgeries. No major complications have been observed in the short follow up period …link_to_OA_fulltextThe 18th International Meeting on Advanced Spine Techniques (IMAST), Copenhagen, Denmark, 13-16 July 2011. In Final Program of 18th IMAST, 2011, p. 93-94, Paper no. 7