supplementary information for physicians treating children in the
Transcription
supplementary information for physicians treating children in the
Information for Physicians Treating Children in the Original von Rosen splint Associate Professor Göran Hansson, MD, PhD The Queen Silvia Children’s Hospital Gothenburg Sweden Copyright©Medi-Estate 2013 Efficacy of the Screening Program for Hip Instability in Newborn Infants on the Maternity Wards in Sweden In Sweden, with a population of 9.5 million and 100.000 deliveries each year (Fig. 1), the incidence of children with developmental dysplasia of the hip (DDH) has been estimated to 1-2 per thousand live births (15). Screening for children with neonatal hip instability (NHI), who run a risk of developing displaced hips, has been practiced by the paediatricians on the maternity wards for more than 50 years (without the use of hip ultrasonography) (7,13). Prior to commencement of the screening program in the 1950s between 100 and 120 late diagnosed cases of DDH were referred to the orthopaedic departments each year (Fig. 2). In almost all these children the diagnosis was established after the first year of life and less than 4 % of the hips “developed well” when treated by the methods used at that time (14). Since the early 2000s the number of late diagnosed cases has declined to about 15 cases each year (Fig. 2) (2). These figures show that in about 90 % of the children with DDH the diagnosis nowadays is established before children are discharged from the maternity wards. Further, of the late diagnosed cases “missed” at the primary screening on the maternity wards, about 80 % are now picked up during the first 6 months of life at the Child Welfare Clinics (13). When the diagnosis has been established this early in children with late diagnosed DDH the reported success rate when treating these children, in the great majority by closed reduction, has been over 90 % in Birth Statistics Sweden (16). Sweden 1948-2008 140000 120000 Live births 100000 80000 60000 40000 20000 0 Figure 1. Live births in Sweden, 1948-2008. 140 130 120 110 100 Number 90 80 70 60 50 40 30 20 10 0 Figure 2. Number of late diagnosed cases of DDH in Sweden, 1948-1960, 1973-1979 and 2000-2008 (2, 13). In about 90% of children with DDH in Sweden, the diagnosis is established on the maternity wards. Prerequisites for reliable braces for children with unstable hips at birth In order to be able to maintain concentric reduction of the femoral head in the acetabulum in children treated for NHI, which is a prerequisite for normal development of the hips, the hips must be positioned in the brace with a sufficient amount of both 1. abduction, in what is referred to as “the safe zone” (Figs. 3 A and B) and 2. flexion (Figs. 4 and 5). A. Hip Abduction If a sufficient amount of hip abduction is not achieved in the brace, there is a considerable risk that the femoral head may subluxate or even dislocate dorsally out of the acetabulum (Fig. 3 B). When this happens, a possible adverse effect of brace treatment, and it is not recognised promptly “posterior acetabular dysplasia“ will develop, which is difficult to treat successfully (1,10). To prevent this from happening the hips have to be posioned in 60-70 degrees of abduction. A. RT LT B. Figure 3. Abduction positioning in braces in “the safe zone” to prevent posterior displacement of the femoral head. A. Sufficient abduction must be achieved in the splint without using any force to prevent both posterior displacement of the femoral head and AVN (Netter illustration from www.netterimages. com.©Elsevier Inc. All rights reserved.). B. CT scan of hips in a patient treated for neonatal hip instability in a Pavlik harness. On the left side the hip is positioned in far too little abduction and the femoral head (non-ossified) is completely dislocated posteriorly out of the acetabulum. On the right side the hip is positioned in more abduction and the femoral head with an ossified nucleus is positioned in the acetabulum To prevent posterior displacement of the femoral head out of the acetabulum when treating children for NHI in the Original von Rosen splint the hips must be abducted 60-70 degrees in the splint. B. Hip Flexion To maintain concentric reduction of the femoral head in the acetabulum, the hips must also be positioned in a sufficient amount of flexion in the brace (Figs. 4 and 5). RT LT RT LT A. RT B. LT C. RT LT D. Figure 4. A. Radiographs of both hips obtained after 6 weeks´ treatment in a Frejka pillow in a child judged to have unstable hips at birth. Residual displacement of the right hip. B. Arthrograms of both hips obtained at 6 weeks show on the right side, with the hip flexed 90 degrees, that the femoral head is dislocated out of the acetabulum and on the left side the hip concentrically reduced. C. With the right hip further flexed, the femoral head enters the acetabulum with an infolded limbus. D. After treatment in a hip spica with the hips flexed more than 90 degrees for 4 weeks, the femoral head has now entered the bottom of the acetabulum and the limbus is in the correct position. Conclusion: The residual displacement of the right hip seen at 6 weeks was due to the Frejka pillow having postioned the hips in insufficient flexion and was not due to intra-articular obstruction preventing concentric reduction. RT LT Figure 5. Radiographs obtained of both hips in a child in the Original von Rosen splint treated since birth in the splint for bilateral hip instability. The left hip is dislocated due to insufficient flexion in the splint. The right hip is correctly positioned. To prevent proximal displacement of the femoral head out the acetabulum when treating children for NHI in the Original von Rosen splint the hips must be flexed more than 90 degrees in the splint. The Original von Rosen splint The Original von Rosen splint was designed by the late Professor Sophus von Rosen of Sweden in 1956 for newborn infants with unstable hips. The splint has been used nationwide in Sweden for more than 50 years with the aim of preventing the development of permanently displaced hips in children born with unstable hips. So far 703 patients treated in the splint have been reviewed in the literature (Table 1). When treatment is commenced during the first week of life and the splint is applied correctly and treatment is monitored by weekly control in outpatient clinics, the reported success rate has been over 95 % and the incidence of avascular necrosis of the femoral head - AVN - less than 1 %. To achive these results the following points must be considered. 1. The children must be seen once a week in the outpatient clinic by a nurse to A. Check that the splint is positioning the hips correctly. B. Decide if the splint should be changed to a larger size (7 sizes). C. Rule out skin problems. D. Have a bath. E. Give the parents general advice. 2. Ultrasonograms of the hips must be obtained after 6 weeks’ treatment in the splint to A. Rule out persistent displacement of the femoral head (extremely rare). B. Decide for how long the child should be treated in the splint. 3. Treatment lasts for 6 – 12 weeks A. Children with primarily dislocated or dislocatable hips should be treated for 12 weeks. B. Children with primarily subluxatable hips and normal ultrasonograms at 6 weeks should be treated for 6 weeks. C. Children with a family history of DDH should be treated for 12 weeks. Sizes of the Original von Rosen splint 1. Mini 2. Small-1 3. Small-2 4. Medium 5. Large-1 6. Large-2 7. Extra large. Of all Original von Rosen splints used, Small-2 and Medium account for 65 %. For the hips to develop normally in the treatment of children with NHI in the Original von Rosen splint, strict and careful routines must be practiced. Application of the Original von Rosen splint Figure 6. To maintain concentric reduction of the femoral head in the acetabulum the hips must be flexed more than 90 degrees and abducted 60 - 70 degrees. To prevent development ofavascular necrosis of the femoral head - AVN - some hip motion must be possible in the splint and forced abduction be avoided. When the Original von Rosen splint is applied correctly, the hips are positioned in over 90 degrees of flexion and 60-70 degrees of abduction. Some hip motion must be allowed in the splint. Two types of rubber coverage are available: 1. Natural rubber. 2. Synthetic rubber. Algorithm to be used when treating children in the Original von Rosen splint Orthopaedic Assessment of Children referred from the Maternity Ward for Suspected Neonatal Hip Instability Hips Dislocated or Dislocatable Orthopaedic Assessment of Children referred from the Maternity Ward for Neonatal Hip Instability Hips Hips Subluxatable Stable Hips Dislocated or Treatment Dislocatable Hips Subluxatable Treatment Hips Stable Treatment Weeks: 6 Weeks: 12 Treatment Ultrasound Weeks : 12 Radiographs Week: 6 Ultrasound Months: 4+12 Radiographs Weeks: 6 Months: 6+12 Treatment Weeks : 6 Ultrasound Radiographs Week: 6 Ultrasound Weeks: 6 None Treatment None Ultrasound Radiographs Months: 4+12 Week: 6 Month: 4 Radiographs Ultrasound Radiographs Months: 6+12 Weeks: 6 Months: 3 Ultrasonograms obtained at 6 weeks are used to ensure: 1. that children primarily judged to have stable hips do not need treatment. 2. that hips are not displaced after 6 weeks´ treatment. 3. that 6 weeks´ treatment is not insufficient in children primarily judged to have subluxatable but not dislocated or dislocatable hips. Fig X. Algorithm to be used when treating children in the Original von Rosen splint. Treatment in the Original von Rosen splint lasts for 6-12 weeks depending on the degree of initial hip instability and what ultrasonograms reveal after 6 weeks´treament. Detection of failure of the splint to maintain concentric reduction of the femoral head It has been reported in the literature to be extremely rare that the original von Rosen-splint has failed to maintain concentric reduction of the femoral head in the acetabulum when treatment is commenced during the first week of life (Table 1). When this happens, however, it is essential to detect the residual displacement of the femoral head as early as possible as this will increase the likelihood that supplementary treatment will be successful. In late diagnosed cases with displaced hips, the diagnosis is usually established by clinical examination revealing limited hip abduction, due to contracted adductor muscle. However, if the child has been treated in abduction braces since the first week of life the adductor muscles will have been stretched so much that limited hip abduction is rarely seen when abduction treatment has failed to prevent displacement of the femoral head. To detect residual displacement of the femoral head after early brace treatment, either ultrasonograms or radiographs therefore have to be used and it is advisable that preferably ultrasonograms of the hips are obtained no later than after 4-6 weeks´ treatment in the splint (Fig. 7). RT LT Figure 7. Residual displacement of the right femoral head and a poorly developed acetabulum after 8 weeks´ treatment in a Frejka pillow in a child judged to have unstable hips at birth. When this radiograph was obtained the clinical findings were, however, assessed as normal. After supplementary treatment in a hip spica the child devoloped normal hips. To detect residual displacement of the femoral head during treatment in braces in children treated for NHI, which is often not possible to detect by clinical examination, ultrasonograms of the hips should be obtained no later than after 4-6 weeks´ treatment in the brace. Results of early treatment in the Original von Rosen splint The results of early treatment in the Original von Rosen splint have been reviewed in studies from both Sweden and the UK (Table 1). Data about 926 children treated from birth in the splint have been published. In only 13 (1.4 %) of these children did the initial treatment in the splint fail. Further, the reported incidence of avascular necrosis of the femoral head (AVN) has been less than 1 % when treatment has commenced during the first week of life and the splint has been applied correctly, allowing some hip motion, and forced abduction been avoided (7). Table 1. Review of the literature on patients treated in the von Rosen splint. Author Primary number of children Children who received supplementary treatment Finlay et al (1967) 60 4 Emneus and Undeland (1970) 68 0 Mitchel (1972) 100 6 Fredensborg (1976) 111 0 Hansson (1983) 160 1 Heikkilä (1988) 180 1 24 0 Lauge-Pedersen et al. (2006) 223 1 Total 926 13 Wilkinson et al (2002) More than 95% of the children treated for neonatal hip instability in the Original von Rosen splint develop normal hips if treatment in the splint is monitored correctly and the incidence of AVN should be below than 1%. Problems which may occur during treatment in the Original von Rosen Splint It usually works well to keep the child in the Original von Rosen splint. However, the following two problems may occur: 1. Loss of correct positioning of the hips in the splint. 2. The splint causes skin problems. These two problems can usually be prevented if the following points are considered A. Preventing loss of correct positioning of the hips in the splint by 1. Selecting the correct size of the splint and later on changing to a larger size (7 sizes). 2. Keeping the hand under the buttocks when lifting the child. 3. Not pulling the legs and feet. 4. Not using tight trousers. 5. Not using a pillow higher than 2 centimeters. B. Preventing development of skin irritation by 1. Washing the baby in the splint regularly using unperfumed soap. 2. Washing the baby´s back with the baby remaining in the splint and the upper splint arms retracted. 3. Wiping the skin dry after washing, especially where the splint is in contact with the skin. 4. Powdering the child and the splint with a thin layer of unperfumed powder. 5. Air-drying the skin on the back by keeping the child on it´s tummy under observation. 6. Not using any ointment. 7. Changing diapers frequently. 8. Preventing the child from perspiring. 9. If there is skin irritation on the back, putting cotton compresses between the skin and the splint. C. See also enclosed folder Information for Parents of Children Treated in the Original von Rosen splint Most problems which may occur during treatment in the Original von Rosen splint can be avoided by seeing the children in the outpatient clinic for general advice every week. Case report 1 RT LT A C B D E Figure 8. Girl assessed to have unstable hips at birth. A. Plain radiograph obtained during the first week of life: dysplastic acetabuli on both sides and left hip displaced. B. Static ultrasonogram of left hip according to Graf during the first week of life: poorly covered non-ossified femoral head and dysplastic acetabulum. C. Static ultrasonogram of the left hip obtained after 6 weeks´ treatment in the Original von Rosen splint: significant improvement with better coverage of the femoral head and impairment of acetabular dysplasia. D. Plain radiograph obtained at 10 weeks: no residual displacement and well developing acetabuli on both sides. E. Plain radiograph obtained at 18 months: normal development both hips with ossified femoral nuclei on both sides correctly positioned in normal acetabuli. Case report 2 B A C D Figure 9. Girl with bilateral unstable hips at birth and a family history of DDH. A. Static ultrasonogram according to Graf of the left hip obtained during the first week of life: dysplastic acetabulum and a poorly covered non-ossified femoral head (Graf: Typ III). B. Static Ultrasonogram obtained after 6 weeks´ treatment in the Original von Rosen splint: significant improvement with better coverage of the femoral head and impairment of the acetabular dysplasia. C-D. Plain radiographs obtained at 8 months: normal development with ossified femoral nuclei, well developed acetabuli and the hips concentrically reduced on both sides. Summary When starting a screening program for children with neonatal hip instability (NHI) on the maternity wards the challenge includes: 1. how to organize successful primary screening on the maternity wards and selection of a reliable brace and 2. proper supervision of the treatment in the brace. A. Organizing a successful screening program for children with NHI The reported success rate of screening of children for NHI has varied considerably. There is much to be learnt from the unique experience gained in Sweden from more than 50 years of screening these children on the maternity wards, documented in a number of theses and articles over the years. Thus, we can conclude that of the children who would have developed dislocated hips (DDH) if no screening was practiced on the maternity wards, about 90 % are nowadays diagnosed during the first few days of life. In addition, the great majority of the children “missed” at the primary screening in Sweden are picked up during the first six months of life at the Child Welfare Clinics, when succesful treatment with closed reduction is still possible in about 90 % of these children (13, 16). “The Swedish experience“ has taught us that to be able to pick up 90 % of the children with NHI on the maternity wards the following points have to be considered: 1. The most essential point is that the paediatricians in charge of screening newborn infants for NHI on the maternity wards are well familiar with examining the hip joints of newborn infants using both Ortolani’s Test and Palmén-Barlow´s Tests. 2. The examination of the hip joints must be undertaken during the first two days of life. After this age the clinical findings are more difficult to assess correctly. 3. The child must be completely relaxed at the examination and a warming device must be positioned over the examination table. 4. It is advisable to obtain ultrasongrams of the hip joints of all children with a family history of DDH, both static and dynamic views of the hips. 5. It is essential not to overlook examination of the hip joints of children treated at the neonatal intensive care unit. 6. Clinical screening is sufficient when paediatricians well familiar with examining the hip joints of newborn infants are in charge of the screening for children with NHI on the maternity wards and ultrasonograms only need to be obtained on special indications. Unless the responsibility for the primary screening of children for neonatal hip instability is given to paediatricians well familiar with examining newborn infants for hip instability and the examination is performed during the first 2 days of life, children with DDH will continue to be missed at the primary screening on the maternity wards. B. Monitoring treatment in the Original von Rosen splint The Original von Rosen splint, which was designed ONLY for newborn infants with NHI, has in several studies been documented to be a reliable brace for these children. In order to achieve a success rate of 95 % and less than 1% risk of development of AVN when using the Original von Rosen splint, which has been achieved both in Malmö and in Gothenburg, the following points must be considered: 1. The splint must position the hips in more than 90 degrees of flexion and 60 - 70 degrees of abduction. 2. To prevent adverse effects of treatment like AVN, some hip motion must be possible in the splint and forced abduction be avoided. 3. The parents should not be allowed to remove the splint at home. 4. The child must be seen in “the hip clinic” once a week by a nurse to: 1. Check that the splint is correctly applied. 2. Decide when it is time to change the splint to a larger size. 3. Ensure that no “skin problems” have occurred. 4. Have a bath. 5. Give the parents general advice. 5. The parents should be able to get in touch with a nurse at the hip clinic on the phone if they are having problems with keeping the child in the splint. 6. After 6 weeks of treatment, the child must be seen again by a physician and static ultrasonograms of the hips be obtained to rule out the possibility that the hips are still displaced (which is extremely rare and often not possible to detect by clinical examination). These ultrasonograms can also be used as a helpful tool to decide if the child should be treated for 6 or 12 weeks in the splint. 7. Children with primarily dislocated or dislocatable hips should be treated for 12 weeks. 8. Children with primarily subluxatable but not dislocatable hips and normal ultrasonograms at 6 weeks should be treated for 6 weeks. 9. Children with a family history of DDH should be treated for 12 weeks. 10.Final radiographs of the hips should be obtained after the child has started to walk and no later than at the age of 12 months. This treatment regime, lasting for 6-12 weeks, may seem complicated to follow. However, compared to what will be the case when the diagnosis DDH is established late and long periods of treatment in a hip spica and/or surgery are usually needed, there is a considerable gain to achieve both from the treatment point of view as well as with regard to the possibility of getting the hip joints to develop in a normal manner when treatment in the Original von Rosen splint is commenced at birth. Manufacturer of the Original von Rosen splint ISAKSSONS GUMMIFABRIK AB Ängalagsvägen 226 SE-269 95 Båstad Sweden Phone: +46 431 36 31 60 Fax: +46 431 36 31 82 E-mail: isakssons@bjarenet.com www.originalvonrosen.com References 1. Atar, D., Lehman. W. and Grant, A. (1993) Pavlik Harness Pathology. J Pediatr Orthop Part B: 75-77. 2. Düppe, H. (2012) Personal communication. 3. Emneus, H and Undeland, K. (1970) Två olika mönster för behandling av congenital höftledsluxation. Opusc. Med.: 357-360. 4. Finlay, H. V. L. et al. (1967) Dislocatable hip and dislocated hip in the newborn. Brit Med J 4: 377-381. 5. Fredensborg N. (1976) The results of early treatment of typical congenital dislocation of the hip joint in Malmö. J. Bone Joint Surg Br vol 58-B, No 3, August: 272 – 278. 6. Hansson G. et al. (1983) Screening of children with congenital dislocation of the hip joint on the maternity wards in Sweden. J Pediatr Orthop, 3(3): 271-279. 7. Hansson, G. (1988) Congenital dislocation of the hip joint: Problems in diagnosis and treatment. Current Orthopaedics 2: 104-111. 8. Hensinger, RN. (1979) Congengintal Dislocation of the Hip. Ciba Clinical Symposia;31(1). 9. Heikkila E. (1988) Comparison of the Frejka Pillow and the Von Rosen splint in the Treatment of Congenital Dislocation of the Hip. J Pediatric Orthop 8: 20-21. 10. Jones, G. T., Schoenecker, P. L. and Dias, L. S. (1992) Developmental Hip Dysplasia Potentiated by Inappropriate Use of the Pavlik Harness. J Pediatr Orthop 12(6) : 722-6. 11.Lauge-Pedersen, H. et al. (2006) 6 Weeks with the von Rosen splint is sufficient for treatment of neonatal hip instability. Acta Orthop April, 77(2):257-61. 12. Mitchel, G. P. (1972) Problems in early diagnosis and management of congenital dislocation of the hip joint. J Bone Joint Surg 54-B: 4-12. 13. Palmén, K. (1984) Prevention of congenital dislocation of the hip. The Swedish experience of neonatal treatment of hip joint instability. Acta Orthop Scand, Suppl 208. 14.Severin, E. (1941) Contribution to the knowledge of congenital dislocation of the hip joint. Acta Chir Scand, Suppl 63. 15. Severin, E. (1956) The frequeny of congenital dislocation of the hip and congenital equino varus in Sweden. Nord Med:55:221-223 (in swedish). 16. Strömquist, B. and Sundén, G. (1989) CDH Diagnosed at 2 to 12 month of Age – Treatment and Results. J Pediatr Orthop, Vol 9: 2: 208 – 212. 17. Wilkinsson A.G. et al. (2002) The efficacy of the Pavlik harness, the Craig splint and the von Rosen splint in the management of neonatal dysplasia of the hip: A comparative study. J Bone Joint Surg Br; 84(5): 717-19.