Cytotoxic agents are detrimental to bone formed by distraction osteogenesis.

UNLABELLED: Distraction osteogenesis can be used to replace segmental bone loss when treating malignant bone tumors in children and adolescents. These patients often receive cytotoxic chemotherapy as part of their treatment regimen. The effect of cytotoxic drugs on the cellular processes during distraction osteogenesis and the structural and mechanical properties of regenerate bone is unknown. We therefore used a rabbit model of distraction osteogenesis to determine that cytotoxic agents had a detrimental effect on regenerate bone formed by this technique. We administered adriamycin and cisplatinum to 20 rabbits using two different simulated chemotherapy regimens. All rabbits underwent an osteotomy at 12 weeks of age. Distraction osteogenesis began 24 h later at a rate of 0.75 mm a day for 10 days, followed by 18 days without correction to allow for consolidation. Regenerate bone was assessed using plain radiographs, bone densitometry, and mechanical testing. Peri-operative chemotherapy decreased the mechanical properties of the regenerate with regard to yield strain (3.7 × 10(-2) vs. 5.2 × 10(-2)) and energy at yield (2.73 × 10(7) vs. 3.92 × 10(7)). Preoperative chemotherapy in isolation reduced bone mineral density (0.38 vs. 0.5 g/cm(2)), bone mineral content (0.24 vs. 0.36 g), and volumetric bone mineral density (0.57 vs. 0.65 g/cm(2)) with no alterations in the mechanical properties. CONCLUSIONS: Preoperative chemotherapy appears to decrease the volume of regenerate bone, without affecting structural integrity, suggesting that the callus formed is of good quality. The converse appears true for peri-operative chemotherapy.

Slipped upper tibial epiphysis in infantile tibia vara: three cases.

We describe three cases of infantile tibia vara resulting from an atraumatic slip of the proximal tibial epiphysis upon the metaphysis. There appears to be an association between this condition and severe obesity. Radiologically, the condition is characterised by a dome-shaped metaphysis, an open growth plate and disruption of the continuity between the lateral borders of the epiphysis and metaphysis, with inferomedial translation of the proximal tibial epiphysis. All patients were treated by realignment of the proximal tibia by distraction osteogenesis with an external circulator fixator, and it is suggested that this is the optimal method for correction of this complex deformity. There are differences in the radiological features and management between conventional infantile Blount's disease and this 'slipped upper tibial epiphysis' variant.

MR imaging of dysplasia epiphysealis hemimelica: bony and soft-tissue abnormalities.

OBJECTIVE: The purpose of this study is to describe the bony and, to our knowledge, previously unreported associated soft-tissue abnormalities seen on MR imaging of dysplasia epiphysealis hemimelica. CONCLUSION: MR imaging accurately depicted bony and cartilagenous structural abnormalities in multiple planes and revealed previously undescribed secondary changes in menisci, tendons, ligaments, and muscle. MR imaging is of value in the assessment of patients with this disorder.

Cosmetic results of supracondylar osteotomy for correction of cubitus varus.

From 1984 to 1995, 19 patients with cubitus varus resulting from supracondylar humeral fractures underwent lateral closing-wedge osteotomies at The Royal Alexandra Hospital for Children. As the indication for osteotomy in all cases was the cosmetically unacceptable cubitus varus, we reviewed the cosmetic results. Seventeen patients were available for review. Subjective reports from patients and parents, as well as objective clinical assessment by one of the authors, were used to assess these results. According to our grading system, 12 (76%) patients had excellent results. These patients and their parents were satisfied with the cosmetic results, and there was no clinical evidence of a bony prominence over the lateral condylar region or an unsightly operative scar. One patient had a poor result with a lateral bony prominence and an unsightly scar, both of which were clinically obvious. We report that lateral closing osteotomies in children who have not yet reached skeletal maturity produce excellent cosmetic results.

Dysplasia epiphysealis hemimelica: clinical features and management.

Dysplasia epiphysealis hemimelica is a rare developmental bone dysplasia characterized by an osteocartilaginous tumor arising from an epiphysis. We reviewed the clinical and radiographic findings, including magnetic resonance imaging (MRI), of nine new patients with dysplasia epiphysealis hemimelica. The lower limb was involved in all cases with the ankle (talus) and knee (distal femur) being the most common sites. MRI was helpful in defining the site and extent of the osteocartilaginous mass and provided detailed images of associated joint deformity. Often there was a clear plane of separation between the lesion and the normal epiphysis. All cases were observed initially and showed progressive increase in size of the lesion with skeletal growth. Surgical excision was performed in five cases and proved to be difficult. We recommend excision of symptomatic localized, juxtaarticular lesions but do not recommend excision of articular lesions. Postoperative degenerative joint changes occurred in two patients.

Embolization in the treatment of aneurysmal bone cysts.

Eight patients with aneurysmal bone cysts (ABC) were treated with selective embolization as an adjunct to curettage and bone graft in seven cases and as the definitive procedure in the remaining case. The age range was 5-23 years. Symptoms had been present for an average duration of 6 months. The lesions were located in the femur (three), the shoulder girdle (three), the tibia (one), and the pubis (one). Two patients had recurrent lesions, and six were primary. Average follow-up was 3 years (2-4.6 years). There were no recurrences and no complications related to embolization. All lesions ossified including the pubic lesion, which was treated with embolization alone. One patient with an ABC adjacent to the distal femoral physis had growth disturbance and a second who had an extensive acromial lesion had mild degenerative changes of the acromioclavicular joint.

Penile deformity in bladder exstrophy: correlation with closure of pelvic defect.

In the exstrophy-epispadias complex of anomalies, penile deformity represents one of the factors that causes long-term disability in males. In order to define the extent to which the separation of the bony elements may contribute to the final penile length and configuration, an in vitro model was devised using an adult male pelvis and an inflatable penile prosthesis. This model was used to study the relationship of interpubic distance to penile length. Closure of the "open book" deformity of the bony pelvis resulted in an increase in penile length. Closure of the pubic diastasis is best accomplished by iliac osteotomies. This study supports clinical evidence that iliac osteotomies, when performed in conjunction with closure of the exstrophic urinary bladder, may contribute to an increase in effective penile length.

Supracondylar osteotomy of the humerus for correction of cubitus varus.

Cubitus varus is the most common complication of supracondylar fracture of the humerus in children. Although function of the elbow is not greatly impaired, the deformity is unsightly. It usually results from malunion, since growth disturbance of the humerus after this fracture is uncommon. The normal carrying angle can be restored by supracondylar osteotomy. This operation was done in 32 patients over a ten-year period, 16 of them using the technique described by French (1959). The results in 27 patients are reviewed in the light of previous reports. French's method proved safe and satisfactory.

Splenic trauma from blunt abdominal injury.

Thirty-nine cases of splenic trauma from blunt abdominal injury are presented. Road trauma was the most common aetiological factor, and young adults were predominantly affected. Internal haemorrhage was the main determinant of the clinical picture, and nine cases of delayed haemorrhage following splenic trauma are reported. Associated injuries were present in two-thirds of cases and contributed to the high morbidity and mortality rate of splenic trauma. The operative and non-operative management of splenic trauma is discussed, and the roles of isotope spleen scans are demonstrated.