Primary malignant bone tumours frequently arise in children close to the knee, hip or shoulder. Resection of the tumour will often require excision of the epiphysis and frequently one side of the involved joint. In these children an extendable endoprosthesis is usually required to allow for maintenance of limb length equality. We have used 180 extendable endoprostheses in 176 children since 1975. The indication for use of an extendable prosthesis was if there was more than 30mm of growth remaining in the resected bone. The age of the patients ranged from 2 to 15 and 99 were boys. The sites of the endoprostheses used were: distal femur in 91, proximal tibia in 42, proximal femur in 11, total femur in 6 and proximal or total humerus in 26. 131 of the operations were for osteosarcoma and 34 for Ewing's. Five types of lengthening mechanism have been used. Two designs used a worm screw gear, one type used a C collar, one type a ball bearing mechanism and the latest uses a non invasive lengthening system whereby a motor inside the prosthesis is activated by an electromagnetic field. Of the 176 patients, 59 have died and of the remainder, 89 have reached skeletal maturity. 19 patients had an amputation, 11 due to local recurrence and 8 due to infection. The risk of infection was 19% in surviving patients. Most of the skeletally mature had equal leg lengths. The average number of operations was 11 but ranged between 2 and 29. Most operations were for lengthening but younger children always needed revisions of the prosthesis. Functional scores were 77%. Extendable endoprostheses are demanding both for the patient and the surgeon. The high complication rate should be decreased by non invasive lengthening prostheses

Introduction. Idiopathic scoliosis is a lateral curvature of the spine >10° as measured on a frontal plane radiograph by the Cobb angle. Important variables in assessing the risk of curve progression include a young age at presentation, female sex, a large amount of growth remaining, the rate of growth, the curve magnitude, and the curve location. Curves >20° have an inherently low risk of progression. Surgery is indicated for curves >50° or rapidly progressing curves. The timing of surgery is paramount in order to intervene in cases where rapid progression is evident to prevent further deterioration. There is a greater likelihood for more complex surgery to be required in major curves. At present, there are severe restrictions on resources to cater for patients with scoliosis. As a result, patients spend excessive periods on waiting lists prior to having their procedure. The aim of this study is to analyse the progression of curves of patients while on the waiting list and assess the cost implications of curve deterioration. Methods. A retrospective analysis of 40 cases of adolescent idiopathic scoliosis performed from between 2007-2010 was carried out. All radiographs at the time of being placed on the waiting list and the time of admission were reviewed to assess the Cobb angle. The radiographs were analysed independently by three spinal surgeons to determine what level of surgical intervention they would recommend at each time point. The final procedure performed was also recorded. A cost analysis was carried out of all of the expenses that are incurred as part of scoliosis surgery, including length of hospital stay, intensive care admission, spinal monitoring, implant cost, and the requirement for multiple procedures. Results. The average time on the waiting list was 12 months (range 6 – 16 months). Comparison of radiographs at the time of listing and time of admission revealed a deterioration of the Cobb angle by an average of 12°. The average Cobb angle at time of surgery was 78° (range 55° - 96°). Analysis of cost implications revealed an increase in cost based on implant requirements, length of stay and intensive care admission estimated at 25%. Conclusion. The results of this study demonstrate that there is a significant deterioration of scoliosis curvature in patients while on the waiting list. The consequence of this progression results in longer operative time, increased requirement for intensive care beds, an increase in requirements for additional levels of pedicle instrument, and a prolonged length of stay. The implications of the deterioration in curvature result in an increase in overall cost estimated at 25%. Waiting list initiatives established over the past 6 months have reduced the waiting list to 6-9 months. Further efforts to continue this initiative are likely to give rise to further cost reductions and result in more manageable curvatures being dealt with in a timely fashion