Operative treatment of scoliosis with Cotrel-Dubousset-Hopf instrumentation. New anterior spinal device

This study analyzes the effects of a new anterior spinal instrumentation system and the results of use in 50 patients with scoliosis.

Anterior spine systems are reviewed. The principles of a new anterior spinal instrumentation system allowing for postoperative care without external support are discussed.

Numerous different implants have been presented in the literature for anterior spinal surgery. Nevertheless a primary stable anterior instrumentation was not available for multisegmental procedures until now, and the restoration of lordosis in the lumbar spine was very difficult with the common devices. The development of more stable devices that also allow a restoration of lordosis in combination with derotation and compression is discussed.

Fifty patients with scoliosis of different etiologies (neuromuscular: n = 33; idiopathic: n = 16; congenital: n = 1) underwent anterior spinal surgery at the thoracic, thoracolumbar, and lumbar spine. During follow-up, no revision operation was necessary after the monosegmental and multisegmental application of this method, and there were no vessel complications. The results were controlled with a mean follow-up of 26.6 (range 12-41) months.

Clinical and radiologic follow-up and complications are reported. Statistical data obtained show a different average blood loss and operation time depending on the different etiology of the scoliotic deformity. The mean corrections for the scolioses by etiology are as follows: myelomeningocele (MMC) (mean preoperative angle 89 degrees, mean correction 54%); neuromuscular (81 degrees, 46%); and idiopathic (55 degrees, 69%). The mean lordosis of the lumbar spine was 29.2 degrees (measured between T12-S1) and could be corrected to 45.2 degrees depending on the etiology of the curvature, whereas the angle of the thoracic kyphosis did not show an essential change. The segmental measurement in idiopathic scoliosis did not show a kyphosization in the lumbar spine. Derotation of the apical vertebra in 15 patients in relation to the sagittal plane was 37%.

The study shows the effect of a new anterior device allowing the application of three-dimensional correction forces to the spine. Particularly in scoliosis derotation, compression and restoration of lordosis are possible. Primary stability is obtained by anchoring the implants with a new wedge-locking technique, which makes postoperative external support unnecessary.