Ten-Year Follow-Up of Jarcho-Levin Syndrome with Thoracic Insufficiency Treated by Prosthetic Rib/Rib Based Construct-Magnetically Controlled Growing Rod Hybrid

Abstract

Summary: Jarcho-Levin syndrome (JLS) results in stunted spine growth due to multiple congenital anomalies and repeated respiratory infections due to insufficient thoracic volume. We report a case with a 10-year follow-up who has been treated by prosthetic rib/ rib based construct (PRRC) and magnetically controlled growing rod (MCGR) hybrid. This strategy addressed the thoracic cage deformity, spine deformity and growth, but continued distraction could lead to sagittal imbalance and kyphosis when maximal spinal height was achieved. Hypothesis: A hybrid PRRC-MCGR construct can improve the chest volume and enhance spinal growth in a case of JLS. Design: A case report. Introduction: JLS is characterised by early onset scoliosis (EOS) and thoracic insufficiency syndrome (TIS). The use of PRRC for the treatment of TIS is well-reported. However, continued rib-rib distraction has no effect on spinal height gain. We report the outcome and challenges of a case of JLS treated by PRRC-MCGR hybrid construct. Methods: A boy with short neck and trunk, and developed respiratory distress after delivery, was diagnosed with JLS. He required oxygen supplementation, had frequent respiratory infections, and the diagnosis of TIS was made at aged 2. He underwent right and left PRRC at the age of 38 and 59 months respectively. During this period, there was minimal gain in spinal height, and rib-to-pelvis MCGRs were implanted bilaterally to distract and lengthen the spine when he was aged 8. At aged 12, no further distraction was possible and there was no increase in body height or spinal length. Serial radiographs showed progressive kyphosis, and all implants were removed. Results: At aged 2 when the PRRC constructs were implanted, his computerised tomography (CT) lung volumetry of 197cm³. His lung volume increased by 51% over the course of subsequent three years. He no longer required oxygen supplementation, and was free from chest infections. He underwent 24 MCGR lengthenings on the left and 21 on the right using an external magnet in the outpatient setting. Over a period of four years, there was an increased in body height by 15.3%, lateral spine height by 5%, C7 plumb line-S1 distance by 93%, and thoracic width by 8%. His CT lung volumetry had increased to 640cm³. After removal of all implants, there was an improvement in his sagittal profile. Conclusion: Our case highlights an innovative use of hybrid PRRC-MCGR construct in the management of TIS in in the context of reduced spinal column length. The addition of MCGR can be considered to maximize spinal growth potential in patients suffering from TIS.