[Congenital anomalies of the spine]

Congenital anomalies of the spine usually originate in (toxic) disturbances during pregnancy. There are occasional hereditary types. These are characterized by the presence of multiple anomalies. Congenital scolioses are often associated with other anomalies like spinal dysraphy (20-30%) and fusion of the ribs. Furthermore heart defects, Sprengel's deformity, cleft palates, hemimelias, clubfeet or congenital vertical talus are frequently associated with congenital scoliosis. We classify in failures of formation, segmentation and combined types. The type of malformation determines the prognosis. One hemivertebra is associated with a risk of progression of 0-2 degrees/year, 2 ipsilateral hemivertebra with 2-3 degrees/year, a unilateral unsegmented bar with 5 degrees/year and a combination of a unilateral unsegmented bar with a contralateral hemivertebra with approximately 10 degrees/year. Conservative treatment is usually ineffective. The indication for operative treatment should be made before the deformity becomes unacceptable, as a correction is difficult and dangerous. The following operations can be carried out: Anterior and/or posterior fusion with or without instrumentation, epiphyseodesis, (hemi)vertebrectomies (with anterior and/or posterior approach), distraction with a halo, osteotomies, separation of the fused ribs and gradual distraction (Campbell's expansion thoracoplasty). The operations carry significant risks and the indication to the various treatment modalities is difficult. Operations should be made under monitoring of sensory and motor evoked potentials. From 498 patients with congenital anomalies of the spine in our observation we have operated on 143. Hemivertebrectomies were the most frequent interventions (56).