Paraplegic syndromes depending on congenital kyphoscoliosis are found very seldom. The authors study the different theories which explain the cord lesion determined by a severe congenital kyphoscoliosis. They emphazise the role of the cord compression between the two walls of durai tube: the first applied against the bone convexity and the second strongly pulled by nerve roots against the posterior surface of the cord. The greatest incidence of cord signs is found between the 15th and the 20th year of age, just when the growth of the individual is more rapid. This fact supports the pathogenic role of the longitudinal stretching of the dura mater. Finally, the spinal torsion and the possibility of vascular vessels compressions are emphazised. A case is reported of a young man, 17 years old, who eighteen months before the examination, after an exaggerated physical stress complained of lumbar pains which motivated the use of an orthopedic cast. Slowly the patient developed motor and sensory disturbances in the lower limbs. At examination, an almost complet paraplegy was found. The only movements still possible were slight flexions and extensions of the great toes. Deep reflexes were exaggerated ; ankle and knee clonus were present ; bilateral Babinski sign. Tactile, pain and thermic hyposthesia up to level of T3; absolut deep anesthesia in the lower limbs. Severe high thoracic kyphosis with thoracic medial dextro-convex kyphosis and slight thoraco-lumbar si-nistro-convex scoliosis. Complete spinal block on manometric tests, and spinal fluid with albumino-cytologic dissociation. X ray pictures demonstrated a high thoracic kyphoscoliosis to the right with apex in T4; triangular hemivertebra corresponding to T4, with its right basis articulated with T3 and T5; absence of the 5th left rib, while the 5th right rib, short, was fused with the 6th rib. The lipiodol test showed a blocking between T3 and T4. Surgical treatment consisted of removal of spinous apophysis and lamina of C5, C6, C7, T1, T2, T3 and T4; a new bone bed was made for the cord, between T1 and T3, by excavation of a portion of transverse processes at left and of interosseous ligaments, costal tubercles and a portion of heads or ribs (this bed was covered with oxycel) ; displacement of the cord to its new bed after bilateral section of roots T1, T2, T3 and T4; the dura was opened for inspection and left with no suture; closure of the wound. Two days after operation, the patient was already able to fleet and extend the feet. About 30 days later, he was able to stand up with support. Neurologic examination made 48 days after the intervention failed to show any muscular complete paralysis, although all the movements of the lower limbs were weak. The deep reflexes were still exaggerated and Babinski sign was present on the right side but inconstant on the left. Superficial sensation was almost normal but deep sensibility was still disturbed. Spinal block was still present until the last examination (70 days after operation), but neurological examination was practically negative. A comparison with reported cases in literature shows that in this patient recuperation was faster and fuller than the great majority.