Introduction: Previous investigation showed that joint distraction (arthrodiastasis) is able to reduce intraarticular pressure and to have a positive effect on the regeneration of bone and cartilage on both sides of the joint. Many reports have been published about the results of arthrodiastasis in the treatment of femoral head necrosis in young children, pointing out good reconfiguration of the femoral head and improved range of motion. In contrast to that, -to our knowledge- there is so far no study showing the effect of hip joint distraction in older children with femoral head avascular necrosis.

Question: In the present study the outcome of the treatment of femoral head avascular necrosis in older children by hip joint distraction was investigated.

Methods: The hip joint distraction method was performed in three patients with necrosis of the femoral head. The causes of avascular necrosis were: Late onset Perthes’ disease in two patients and slipped capital femoral epiphysis (ECF) in one patient. The average age of the patients was 13.4 years. They all suffered from persistent severe pain and mostly limited range of motion of the hip joint. The plain radiographs revealed a Catterall IV, Herring C stade in both patients with late onset Perthes’disease. In the radiograph of the ECF patient a severe deformity of the femoral head was visible. After intraoperative soft tissue release, joint distraction was performed with an Ilizarov-ring fixation and immediately distracted 4–5 mm under image control. Distraction was continued 1 mm per day until the Shenton line was overcorrected. At this time the fixator was changed so that flexion-extension exercises were encouraged with the fixator in place. The patients were kept non-weight bearing. After 4 weeks the fixator was changed, so that in addition abduction up to 30° was possible. In total fixator duration time was 3.5 months. (In one case due to a fracture, the fixator was left for further 3 months) During distraction period with the fixator two patients suffered a femoral fracture without a causal adequate trauma.

Due to these major complications further investigations on additional patients have been stopped.

Results: The outcomes after 2.5 years showed in two patients an ankylosis of the hip joint with adductionflexion contracture and radiographical no reshaping of the femoral head. The third patient had a poor range of motion while radiographic findings showed a good reconfiguration of the femoral head. Nevertheless even in this patient advanced arthrosis was evident.

Conclusion: In conclusion, due to the major complications and the unsatisfactory “middle-term”-results, arthrodiastasis as a therapy of avascular necrosis of the femoral head in older children has failed in our study. In our opinion fracture was as a result of immobilisation osteopenie.

Aim: During periods of rapid growth hip diseases can deteriorate unexpectedly. This retrospective evaluation should determine standard values that might allow earlier determination of such growth disturbances and a better classification of almost normal findings.

Methods: 520 standardized made and normal pelvis x-rays of children aged 4–16 years were examined under respect to the development of the hip and pelvis itself (20 x-ray pictures per age-group and gender). Among others these parameters were assessed: acetabular index (AC) and ACM-angle, acetabular width, depth and length, width and altitude of the epiphysis, transverse pelvic diameter and pelvic altitude.

Results: At the age 6–14 years boys have a higher ace-tabular index and ACM-angle than girls. The acetabular index decreases up to the age of 15 to 10 in average, the ACM-angle up to the age of 9 years to 47 in boys and 45 in girls to be subsequently constant. The bony acetabulum grows concentrically and spherically in form and slower than the femoral head. The acetabulum of girls is deeper, smaller and stops growing at the age of 14. The pelvic growth proceeds with the exception of iliac width in girls up to the age of 16.

Conclusion: Due to an age depending mechanical load of the femoral head on the acetabulum a mild DDH can develop to severe pathology in times of rapid growth. With the found normal values and its variations it is easier to assess the development of hip joints especially in such cases.

Aim: Since the thalidomide-catastrophe in the 50th and 60th the sensibility for children with limb defects has become important in the population. Besides the incidence of limb defects, the aetiology of limb defects is a very important question.

Method: Like the ESPED-Model (Documentation of rare paediatric diseases in Germany) we send every three months a letter to 1073 gynaecological clinics to ask the number of live and still births and the number of limb defects. If there are limb defects announced, a second letter is send to ask details about pregnancy, birth and family. The limb defects are registered after the ICD-10-classification.

Results: Time of registration: 48 months (April 2000 – April 2004). Number of all registered births: 1070541, number of live births with limb defects: 1534 (0,14%), number of still births with limb defects: 55 (1,7%), minor limb defects like polydactyly (22,4%) are more often than major defects of the tibia (1,0%) or of the fibula (1,6%), hereditary in 9,7%, no correlation to the profession of parents or their age, no correlation to nicotine abuses, nothing special concerned pregnancy (amniocentesis in 3,3%, oligohydramnie in 0,5%, etc.) and birth (caesarean section in 29%, etc.).

Conclusion: It is very important to continue the registration of limb defects in Germany to terminate the number of incidence of the different types of limb defects and to define there aetiology.

Two major complications of hip replacement are loosening and infection. Reliable differentiation between these pathological processes is difficult since both may be accompanied by similar symptoms. Our aim was to assess the diagnostic ability of triple-phase bone scanning (TPBS) and positron-emission tomography (PET) to detect and differentiate these complications in patients with a hip arthroplasty. Both TPBS and PET were performed in 63 patients (92 prostheses). The radiotracer for PET imaging was ¹⁸F-fluorodeoxyglucose (FDG). Image interpretation was performed according to qualitative and quantitative criteria although the final diagnosis was based upon either surgical findings or clinical follow-up.

The sensitivity, specificity and accuracy of PET was 0.94, 0.95 and 0.95 respectively, compared with 0.68, 0.76 and 0.74 for TPBS. We found that an image interpretation based exclusively upon quantitative criteria was inappropriate because of its low selectivity. The histological examination indicated that increased periprosthetic uptake of FDG in patients with aseptic loosening was caused by wear-induced polyethylene particles and the subsequent growth of aggressive granulomatous tissue.

Aim: In Germany an ultrasound screening for CDH is recommended for all children in the þrst 6 weeks of life. We evaluated this program together with the German Association of health insurance carriers over þve years to show if an early ultrasound of the hip can reduce the number and the required operative procedures of children with CDH. Methods: From 1997 to 2002, we documented monthly all otherwise healthy children with CDH aged ten weeks up to þve years in all German orthopaedic paediatric departments with a registration card and questionnaire. Results: Overall we registered 645 children, 534 with single operative procedure. 68% received a closed reduction of the hip, 11% open, while 21% required an osteotomy of the acetabulum and/or femur. The percentage of the single operative procedures did not change over the years. The number of children, who underwent no ultrasound of the hip before diagnosis decreased from 20% in the þrst year to 10% in the last. The þrst ultrasound examination revealed no pathological þndings in 20% of the cases. Children received the þrst screening more and more at the age four to six weeks than during the þrst days of life. Nevertheless, the yearly number of cases declined by 50%. Conclusion: Despite the ultrasound-screening-program late or undiagnosed CDH still exists in our country. A possible reason can be the quality of ultrasound examination, the form of treatment as well as a later worsening of CDH and the so-called endogenous dysplasia.

Aim: In Germany an ultrasound screening examination to determine CDH is recommended for all children in the first 6 weeks of life. We evaluated this ultrasound-screening-program together with the German Association of health insurance carriers over five years to show if an early ultrasound of the hip can reduce the number and the required operative procedures of children with CDH.

Methods: From 1997 to 2002, we documented monthly all children with CDH aged ten weeks up to five years from all German paediatric orthopaedic departments with a registration card and questionnaire. Children with neuromuscular diseases or teratologic dislocation of the hip, enrolled in out-patient treatment programs, as well as children born abroad were excluded.

Results: Overall we registered 645 children, 534 with single operative procedure. 68% received a closed reduction of the hip, 11% open, while 21% required an oste-otomy of the acetabulum and/or femur. The percentage of the single operative procedures did not change over the years. The number of children, who underwent no ultrasound of the hip before diagnosis decreased from 20% in the first year to 10% in the last. The first ultrasound examination revealed no pathological findings in 20% of the cases. During the five years children received the first screening more and more at the age four to six weeks than during the first days of life. Nevertheless, the yearly number of cases declined by 50%.

Conclusion: Despite the German ultrasound-screening-program late or undiagnosed CDH still exists in our country. A possible reason can be the quality of ultrasound examination, the form of treatment as well as a later worsening of CDH and the so-called endogenous dysplasia. The aim must be the improvement of diagnosis and treatment.

In 21 children with myelomeningocele who underwent kyphectomy for congenital kyphosis of the lumbar spine, aortography revealed no case in which the aorta followed the spinal curvature. Many anomalies of the intercostal and segmental arteries were demonstrated which were only in part associated with deformities of the respective vertebral bodies. The kidneys, which were frequently malformed, often lay within the kyphosis and were therefore at risk of operative damage. We conclude that the aorta is not at risk and that aortography is not usually necessary before kyphectomy, except in patients who have undergone prior abdominal surgery. Non-invasive methods (ultrasound, CT or MRI) should be used to detect malpositions and malformations of the kidneys.