We investigated the effect of adjuvant and neoadjuvant chemotherapy regimens on the tibial regenerate after removal of the external fixator in a rabbit model of distraction osteogenesis using New Zealand white rabbits. Forty rabbits were randomly distributed into two groups. In the neoadjuvant group, half of the rabbits received 1mg/kg cisplatinum & 2mg/kg adriamycin at eight weeks of age followed by 1mg/kg cisplatinum & 4mg/kg adriamycin at ten weeks of age. The remaining ten received an identical volume of normal saline using the same regimen. The adjuvant group differed only in the timing of the chemotherapy infusion. Half received the initial infusion ten days prior to the osteotomy, with the second infusion four days following the osteotomy. Again, the remaining ten rabbits received an identical volume of normal saline using the same regimen. This produced an identical interval between infusions and identical age at osteotomy in both groups. All rabbits underwent a tibial osteotomy at 12 weeks of age. Distraction started 24hours after osteotomy at a rate of 0.75mm a day for 10 days, followed by 18 days without correction to allow for consolidation of the regenerate. At week 16 there was no difference in Bone Mineral Density (BMD), Bone Mineral Content (BMC) or volumetric Bone Mineral Density (vBMD) in the adjuvant group. Neoadjuvant chemotherapy appears to have a significant detrimental effect on BMD, vBMD and BMC. Despite this there were no significant alterations in the mechanical properties of the regenerate. Histologically there was a trend for increased cortical thickness in the control groups compared to intervention however this did not prove statistically significant. In conclusion, adjuvant chemotherapy may be more beneficial for cases where distraction osteogenesis is being considered to replace segmental bone loss after tumour excision.
We report 3 cases from different centres of infantile tibia vara in which the deformity was due to slippage of the proximal tibial epiphysis on the metaphysis; the aim of this study was to define the features of this previously unreported condition, and their implications for management. Three cases of tibia vara secondary to atraumatic slippage of the upper tibial epiphysis on the metaphysis were identified from three different centres. The case notes and imaging studies were retrospectively reviewed to distinguish common clinical and radiographic features.Introduction
Method
Distraction Osteogenesis can be complicated by regenerate insufficiency resulting in prolonged implant usage or regenerate failure with malalignment or fracture. Experimental evidence has demonstrated that bisphosphonates may mediate improved local limb BMD and regenerate strength. A prospective series of 14 patients over 5 years. One cohort (Group A) of these cases presented with established regenerate insufficiency leading to consideration for surgical intervention. Patients received a therapeutic regime of intravenous bisphosphonate A further cohort (Group B) of 7 patients was commenced on bisphosphonate therapy at an earlier stage, prior to the regenerate maturation phase.Background
Methods
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.
