Cervical kyphosis in patients who have Larsen syndrome.

Four patients who had Larsen syndrome and cervical kyphosis were managed operatively and followed for an average of seventy months (range, forty to ninety-two months). The preoperative cervical kyphosis ranged from 35 to 65 degrees. The patients had had a posterior cervical arthrodesis alone when they were infants, at an average age fo fourteen months (range, ten to sixteen months). In three infants, the kyphosis either stabilized (one patient) or reversed into lordosis (two patients). Thus, the kyphosis corrected gradually by continued anterior growth in the presence of a solid posterior fusion. In the fourth infant, the kyphosis progressed to 110 degrees because of pseudarthrosis. This child had anterior decompression and arthrodesis for an acute neurological deficit. We believe that cervical kyphosis is sometimes present but not diagnosed in patients who have Larsen syndrome. Early diagnosis followed by operative stabilization should help such patients avoid neurological deficits. Posterior cervical arthrodesis alone, performed in infancy, provided stability and the opportunity for the gradual correction of the deformity by continued anterior growth in three of our four patients.