Flexible and semi-early vertebral instrumentation in surgical treatment of Duchenne muscular dystrophy scolioses

Abstract

1) Purpose of the study. The purpose of this work is to demonstrate the advantage of early surgical intervention for those suffering from Duchenne muscular dystrophy scoliosis. 2) Material: This review relates to 37 patients suffering from Duchenne muscular dystrophy. There are detailed results in connection with the first 24, curves offering the longest follow-up period, each a minimum of at least three years. The study on complications relates to the first 37 cases. 3) Methods: Surgery on all patients involved the insertion of flexible vertebral instrumentation. This instrumentation comprises a pedicular screwing system in the lumbar-sacral area and transversal attachments with steel threads at the thoracic level. Bone bank arthrodesis was performed only at lumbo-sacral level, in order to maintain flexibility in the thoracic part of the assembly and to maintain growth. 4) Results: Throughout the series no further intervention was necessary for technical reasons. Four superficial sepses were treatable locally along with an antibiotherapy without removal of material. Regretfully there was one stem rupture two years after operation, caused by a road traffic accident. There was no death during the longest follow-up period. In the frontal plane, the pre-operative Cobb angle was 19.°. It was brought to 5.2° at the post-operative stage, and at the latest measurement was 9.50, i.e. a loss of angular correction of 4,3°. In the sagittal plane, there are physiological curvatures. Pelvic balancing is correct and results have held over time. Pre-operative vital capacity was 62 %, since then it has reduced by 3.6 % per year. 5) Discussion: These results and a review of the literature encourage us to operate early on these patients in order to avoid anaesthetic, peri- and postoperative complications. Likewise, operating early, and therefore giving support to minor curves, reduces mechanical constraints during the first postoperative years. Changes in vital capacity as recounted in literature show contradictory results. These do not allow conclusions to be drawn as to whether it stabilises. It seems partly to lessen its deceleration. The absence of thoracic arthrodesis enables growth of about 5 cm where patients are operated on at about the age of 12 years. 6) Conclusion: Stabilisation of the myopath's spine enables the child to remain in an upright sitting position. The assembly's thoracic suppleness enables us to increase the range of movement in the upper limbs. It seems appropriate to operate on such patients when they cease walking, around the age of 12. Likewise, while neither respiratoty function nor life expectancy is improved, we note that most patients, and those around them, are very satisfied by the comfort brought about by the intervention