The results of resection of the lordotic segment cephalad to the apical
vertebra of a kyphotic deformity in thirty-nine patients who had had a
myelomeningocele were reviewed retrospectively. The operations were
performed between 1973 and 1984, when the patients were an average of six
years and ten months old (range, one year and five months to twenty years
old). The average duration of follow-up was eleven years and one month
(range, five years and one month to seventeen years and four months). The
average preoperative kyphosis was 111 degrees (range, 77 to 151 degrees)
and the average postoperative kyphosis was 40 degrees (range, 2 to 88
degrees). The preoperative deformity was reduced an average of 64 per cent
(range, 0 to 98 per cent). At the latest follow-up evaluation, the average
kyphosis was 62 degrees (range, -25 to 100 degrees). The measurements were
obtained from lateral radiographs that were made with the patient sitting
preoperatively, immediately postoperatively, at one year, and yearly until
the time of the latest follow-up evaluation. At the most recent
examination, thirty-four patients had a partial loss of correction, with
twenty-five of them having maintained at least 50 per cent of the
correction. The five remaining patients had an improvement in the alignment
by an average of 26 degrees. Only two patients had an increase in kyphosis
compared with the preoperative deformity. Thirty-seven patients had an
average increase of 3.2 centimeters (range, 0.2 to 8.2 centimeters) in the
height of the lumbar spine; the two remaining patients, who had a decrease
in height, had operative intervention after reaching skeletal maturity.