Anterior innominate osteotomy in repair of bladder exstrophy.

BACKGROUND: Classic bladder exstrophy is a developmental defect presenting at birth with a wide pubic separation and an exposed bladder; cloacal exstrophy involves, in addition, intestinal prolapse. Reconstruction requires several surgical procedures. The use of anterior iliac osteotomies in this process has not been reviewed in a large series. METHODS: We reviewed the results of eighty-six anterior innominate osteotomies performed in conjunction with genitourinary repair of classic and cloacal bladder exstrophy in eighty-two patients. Clinical outcome measures were successful bladder closure, achievement of continence, and maintenance of a normal gait. Radiographs of the pelvis were reviewed, and the pubic intersymphyseal diastasis (a measure of the reduction in tension on the anterior closure) was measured preoperatively and at three time-points postoperatively. Children with classic exstrophy who had undergone osteotomy and bladder neck reconstruction but not bladder augmentation were divided into four groups on the basis of the degree of continence. In addition, children with classic exstrophy were stratified according to age at the time of the osteotomy. The mean postoperative percent reduction in the amount of the original diastasis was determined for all groups. RESULTS: Children with classic exstrophy and those with cloacal exstrophy had correction of the diastasis after the osteotomy, with greater correction in those with classic exstrophy, presumably because of better bone quality. Daytime continence was achieved with anterior osteotomy and bladder neck reconstruction in 74% of the children for whom continence was a goal. However, no difference in the symphyseal diastasis or in the percentage of pubic reduction was detected among the four continence groups. Children who were older at the time of the osteotomy maintained better correction over time. Wound dehiscence or bladder prolapse occurred in 4% of the patients who had osteotomy and primary closure, and the only important complication of the osteotomies was transient palsy of the left femoral nerve in seven children. CONCLUSIONS: Anterior innominate osteotomy is an effective part of reconstructive repair of bladder exstrophy. The primary goals of the osteotomy are to reduce the tension in the closed bladder and the lower abdominal wall and to promote continence by restoring the sling of the pelvic floor muscles. These goals can be achieved in the majority of patients.

The hip in adults with classic bladder exstrophy: a biomechanical analysis.

We studied the untreated pelvic deformity in 14 adult patients with bladder exstrophy to determine the relative hip-joint force and stress and their effects on the clinical status of the hip. Pelvic radiographs were used for biomechanical analysis to calculate joint force and joint stress (force/area) relative to partial body weight, which allowed comparison between patients and age-matched controls. IOWA hip ratings were used for clinical evaluation, and hips were scored radiographically for degenerative joint disease. The mean relative joint force and joint stress was significantly higher for exstrophy patients (p < 0.001). In addition, the mean distance from the body center to the center of the femoral head was significantly increased (p < 0.001) in bladder exstrophy patients. An increase in diastasis correlated with an approximate 30% increase in the distance from the center of the femoral head to the body midline. The mean distance from the greater trochanter to the femoral head center was significantly less (p < 0.02) and the center-edge angle was significantly decreased in exstrophy patients (p < 0.05). Two patients' hips showed significant subluxation, and one of these showed degenerative hip disease in association with poor IOWA and radiographic scores. The force and stress on the hip joint are increased in untreated adult bladder exstrophy patients. Further longitudinal study is indicated to validate these findings and to determine whether clinically important degenerative changes are occurring. This could affect treatment recommendations in childhood.

Molecular characterization of tiny ring X chromosomes from females with functional X chromosome disomy and lack of cis X inactivation.

Small ring X chromosomes were first described in mosaic karyotypes of females with the relatively benign phenotype of Turner syndrome. The presence of these rings in association with more severe phenotypes including mental retardation has raised the possibility that they lack sequences necessary for X chromosome inactivation, specifically genes within the X inactivation center (XIC) essential for cis X-inactivation. We recently showed that ring X chromosomes ascertained because of the severe phenotype do not express XIST, a candidate for the relevant gene, and that they are in fact active chromosomes. We now report studies of the genetic content of 11 of these ring X chromosomes (9 associated with severe phenotypes). Our results indicate that these chromosomes contain contiguous segments of DNA and have variable proximal and distal breakpoints and some include mainly long arm or mainly short arm sequences. As expected for ring chromosomes, they lack telomeric sequences. Many of the ring chromosomes lack the XIST locus, consistent with XIST being necessary for cis inactivation. However, the breakpoints in four ring chromosomes that have XIST sequences but do not express XIST suggest that other sequences within the XIC distal to XIST as it is now defined are also needed.