Developmental Dysplasia of the Hip (DDH) Amir Ghazavi

Transcription

1 Developmental Dysplasia of the Hip (DDH) Amir Ghazavi 1

2 History Dates back to the time of the Hippocrates. Has been diagnosed and treated for several hundred years. Most importantly, Ortolani an Italian pediatrician in 1900 began evaluation, diagnosis and treatment of DDH. Later on Geleazzi reviewed more than 12,000 cases of DDH. 2

3 Overview DDH is the most common disorder affecting the hip in children. The term developmental dysplasia recently replaced the term congenital dislocation as the accepted name of the condition. DDH vs. CDH CDH implies an already present condition at birth. DDH implies an underdeveloped joint without a dislocation. The dislocation occurs later on. 3

4 Overview: What is DDH? DDH is a congenital condition of the hip joint. It involves instability and the potential for dislocation of the hip joint present at birth. This abnormality of the hip joint causes the femur head not to be held in the hip socket properly. DDH can vary in degree of instability, the femur head can either be partially or completely loose. This instability of the hip may lead to hip dysplasia, abnormal growth of the hip. 4

5 Types of DDH Subluxation, Dislocation, Instability and Tratologic Dislocation Figure -The hip is the largest ball-and-socket joint in the body. The thigh bone (femur) fits tightly into a cup-shaped socket (acetabulum) in the pelvis. Figure- The femur does not fit properly in the acetabelum, causing the thigh bone to dislocate. It is easier for an infant's hip to become misaligned (subluxate) or dislocate than an adult hip. This is 5 because an infant hip socket is mostly soft, pliable, cartilage. Whereas an adult's hip socket is hard bone.

6 Subluxation: Incomplete contact between the articular surfaces of the femoral head and the acetabelum. The hip socket is shallow. 6

7 Dislocation: Lack of contact between the articular surfaces of the femoral head and acetabelum. The hip socket is too shallow. 7

8 Instability: Dislocation of the hip with passive manipulation. The Femoral head is reduced in the true acetabelum. But can be fully (dislocated) or partially (subluxated) removed. Unstable hip joint 8

9 Tratologic Dislocation: Prenatal dislocation of the hip. Often associated with neuromuscular disorders. Figure - The thigh bone is completely out of the hip socket. 9

10 Risk Factors: Once in every 1000 live births Eight times more common in females than males. First child, mostly First-born females Breech position during pregnancy (baby s bottom is down) Family history of the disorder If a parent has DDH, the risk of a child with DDH is 12% (1 in 8) If a parent and a child have DDH, the risk of a subsequent child having DDH is 36% (1 in 3) 1 out of 10 infants with some hip instability if a parent or a sibling already has hip dysplasia Breech Womb Position 10

11 Races: Higher among Native Americans and Laplanders. Approximately cases per 1000 persons. Lower among southern Chinese and black populations. 11

12 Causes Exact cause is unknown. But research has discovered several theories and risk factors for hip dysplasia Factors such as Breech position and firstborns contribute greatly to the onset of DDH. Multi-Factorial condition. Involves both genetic and environmental. 12

13 Other Causes Genetic Factors: Females Twins Postnatal Factors: Swaddling infants Cradle board Hormonal link: Relaxin Estrogen Prenatal Factors: Oligohydramnios Primigravida Congenital knee dislocation. Linked to: Congenital muscular torticollis Matatarsus adductus 13

14 Diagnosis: Most countries employ a standard hip joint exam screening for the early detection of DDH Diagnosis is usually done first by clinical examinations such as a complete prenatal birth history, family history (relatives with DDH) and medical history. A complete dislocated hip may be noticeable, but usually DDH is not discovered until symptoms start to develop. Diagnosis could be more difficult for late DDH, since the only apparent sign may be less mobility or flexibility in the affected hip. 14

15 Diagnosis Physical examinations are the most common method of detecting DDH. However some cases are mild and silent. Diagnostic procedures may include Ultrasound X-ray Computed Tomography Scan (CAT scan) Magnetic Resonance Imaging (MRI). Ultrasounds are done for younger infants to verify the condition. But X-rays are done for much older infants as means to diagnose DDH. 15

16 Diagnosis Early clinical examinations: Ortolani Test: Reduction of the dislocated hip by abduction with knees flexed 90 (+)test: clunk or click when femoral head is relocated. Barlow Test: Dislocation of the reduced hip by adducting and applying longitudinal pressure on the femur and then relocation of the hip via the Ortolani Test. (+) test: femoral head slipping out of the socket post laterally. 16

17 Diagnosis: Clinical examination of late DDH 3-6 months old infants. At this period The hip is dislocated at a fixed position. Unilateral dislocation Easily noticeable. Apparently shorter femur. Skin Fold Test Extra thigh folds Bilateral dislocation Difficult to diagnose. No shortening. 17 Symmetric thigh folds. Femoral length comparison

18 Diagnosis Clinical examination of late DDH Detect unilateral hip dislocation. Geleazzi test: Demonstrates that one leg appears shorter by flexing the hips and knees. Any limb-length discrepancy could result in a positive test 18

19 Diagnosis X-rays and ultrasound provide a more precise and accurate examinations. Ultrasound imaging is done in infants younger than 5 months since it provides a better description of the anatomy until the cartilage is ossified. It is operated as a confirmation to physical tests. X-ray imaging is done in infants older than 4-months. Dislocation can be diagnosed if the Shenton s line is not a smooth arc. 19

20 Diagnosis Figure-These lines are measured and evaluated in X-ray images. Figure -X-Ray image. Showing calculations for working out hip dysplasia. MRI and CT Scans are most often used as a means to monitor progress of treatments. 20

21 Symptoms The signs of DDH vary depending on whether one or both hips are affected. DDH does not cause pain. Untreated DDH may potentially lead to osteoarthritis, which causes pain The symptoms may bear resemblance to other orthopedic conditions. DDH more commonly affects the left hip. both hips can be affected. 21

22 Symptoms Common symptoms include: The dislocated leg appears shorter than the other leg. The dislocated leg might turn outward. Uneven appearance of the folds in the skin of the thigh or buttocks.(unilateral dislocation) Wider space between the legs. Reduced mobility and flexibility of the affected leg. 22

23 Symptoms Symptoms may be detected at birth. In rare cases, DDH may develop weeks or months after birth, where signs might not be seen until the child starts walking. The child may walk with one hip raised higher than the other or walk on toes of one foot to compensate for the difference in length. Walk with a limp or waddling if both hips are affected. 23

24 Symptoms Children with untreated DDD may develop permanent deformities in the hips. Untreated DDH can also lead to hip joint degeneration. Degeneration of the joint s cartilage will lead to Osteoarthritis. The bones will eventually rub against each other and cause damages to the tissue and bone and cause pain 24

25 Prognosis If diagnosed at birth, there is a higher chance of correction. For late DDH, treatments are more sophisticated and there is less chance of correction. The sooner the treatment, higher chance of correction and recovery of the normal hip anatomy and function. However, in some cases successful treatments may not prevent hip deformity and osteoarthritis to develop in children of 2 years or older. 25

26 Prognosis With not treating DDH, the worst possible scenario is the development of early arthritis. DDH is cited as causing osteoarthritis of the hip at a relatively young age. Untreated DDH can contribute to some neuromuscular disorders such as cerebral palsy, Myelomeningocele, Arthrogryposis and Larsen syndrome. 26

27 Treatments It is very important to treat DDH early, otherwise there is a possibility of lasting hip problems. The primary purpose of treatments are to put the femoral head back into the normal position. Additionally, treatments aim to delay the onset of osteoarthritis. Although treatments are successful in avoiding arthritis. Treatments include: Non-surgical positioning devices, casting and surgery. 27

28 Treatments Treatments are specific based on factors: Age Overall health, medical history. The severity of the condition Tolerance for medications and procedures. Expectations of the condition. Late treatments often result in complications and poor results. 28

29 Treatments Frejka Pillow Early DDH, infant less than six months: Can be treated using a Pavlik Harness or the Frejka Pillow/Splint Often end up in normal results in the first year. Mostly effective, but dislocation could still persist. Treatment less likely to work for older infants. 29 Pavlik Harness

30 Treatments Pavlik Harness The Pavlik Harness is the common used positioning device. While allowing little leg movement, the hip joints are kept in place during growth. Pavlik Harness. the Worn full time for at least sixeight weeks. Then part time for legs are positioned like a M another six weeks. X-rays, Ultrasounds and CAT scans are used to check hip placement, when the treatment 30 is done.

31 Treatments Late DDH, infant between six months and 2 years of age: Closed Reduction surgery is done to treat the condition. Closed Reduction refers to manipulation of the femoral head to direct it into place (without surgical exposure). The adjustments are maintained by wearing a Spica cast for a period of three to six months. Closed Reductionanterior hip dislocation 31

32 Treatments Late DDH, infant more than two years old: Open Reduction surgery is performed. A method whereas the hip is opened and the joint is put back into place. The femur head may get strategically broken and rotated to achieve correct alignment. A Spica cast is worn to maintain the proper hip position. X-rays and CAT scan are taken during and after treatment to monitor the progress. 32

33 Treatments Treatments in adults: Total Hip Arthroplasty/Total Hip Replacement. A surgical procedure in which a hip joint is replaced by a prosthetic implant. X-ray image of the hip after surgery. At the right is the prosthetic implant 33

34 Complications Complications could occur, but unlikely. A delay in walking, if cast is used as a treatment. Positioning devices could cause skin irritation. Unstable, abnormal growth of the upper thigh(highly unlikely). Disruption of blood to the femoral head. Onset of arthritis and unbearable pain (untreated DDH, or improper treatment) Possibility of dislocation happening again (Unlikely). Hip Arthritis 34

35 Government Policies Mandatory Ultrasonography in north of Europe Mandatory Physical Examination and Ultrasonography in questionable cases in other countries. Non-mandatory ultrasound screening of children for DDH in Canada. Mandatory physical examinations of infants at birth in Canada. In US, recommendation for screening only for those with obvious dislocations. Non-mandatory screening at birth. 35

36 Conferences and professional organizations Canadian Orthopedic Association American Academy of Orthopedic Surgeons Hip Society 36

37 Models X-ray image of a dog with a hip implant. Different species exhibit different advantages and disadvantages in terms of appropriateness. Non-human primates are regarded as the best models. However there are ethical issues present as well as cost and handling (Pearce et al., 2007). Dog, is considered also appropriate due to its similar bone structure to humans. Yet there are ethical issues. 37 A dog with hip implants.

38 Models o Although animal models such as sheep and pigs are not as ethically emotive, but they pose housing, handling and availability issues (Pearce et al., 2007). o These issues are not as critical in rabbits, even though they may be the least similar in bone structure and properties to humans. 38

39 Models Most common use of models is to determine biocompatibility, mechanical stability and safety of developed orthopedic implants (Pearce et al., 2007). In vitro studies are difficult to be inferred to In vivo situations. Thereby, animal models allow for efficient testing of orthopedic implants and evaluating bone-implant interactions. Commonly used models are: Dog, Sheep, Goat, Pig and Rabbit. 39

40 Models Improvements and developments in treatment of DDH has mostly been accomplished by experiences with different patients. Nevertheless, animal models recently have been used to study DDH and improve treatment procedures. 40

41 Models: Sheep Usage of sheep as a model is increasing. The increase in usage is due to ethical issues concerning of companion animals (Pearce et al., 2007). Currently, it is customary to use sheep as an experimental model to evaluate new orthopedic biomaterials and implants (Potes et al., 2008) Commonly used to evaluate the mechanical behavior of new concepts of hip implants. 41

42 Models: Rabbit Due to ease of handling it is a commonly used animal for medical research, as well as musculoskeletal research (Pearce et al., 2007) Size limitation is a disadvantage, especially for evaluation of multiple implant materials. (Pearce et al., 2007) Currently, used to study the mechanism of hip dislocation. Also used to understand the dysplastic changes at various ages of dislocation. As well as to study the remodeling potential and histology of the acetabelum after dislocation and relocation of the hip (Raab et al., 1998). 42

43 Models: Dogs Commonly used animal for musculoskeletal research. (Pearce et al., 2007) Useful as a model for human orthopedic conditions. Currently, it is used to study the growth and the changes of the shape of the femoral head with dislocated and unstable hip joints (Junk, 2008) Usage of dogs for orthopedic research outnumbers sheep. 43

44 Models Similarities between animal and human bone according to AI Pearce et al (2007). Bone composition Bone Remodeling Dog Sheep Pig Rabbit Macrostructure Microstructure least similar, ++ moderately similar, +++ most similar Clearly, each model species exhibits advantages and disadvantages in terms of similarities in bone structure and thereby their appropriateness in terms of usage as models. The dog and the pig show higher similarities, but in terms of ease of handling, the dog would be a good candidate for an experimental model. 44

45 Conclusions DDH is a congenital condition of the hip. DDH is a condition that can occur in 1/1000 birth If undiagnosed and untreated eventually leads to osteoarthritis and pain. The best and easiest treatment is during neonate and infancy There should be a mandatory screening at birth. The availability of animal models should increase and Extensive research needs to be done on animal models, to find out the exact cause of DDH. 45

46 References 1. DDH / Hip Dysp. (n.d.). PO Home. Retrieved June 15, 2011, from Hip_Dysp/ddh hip_dysp.html 2. Developmental Dislocation (Dysplasia) of the Hip (DDH) - Your Orthopaedic Connection - AAOS. (n.d.). AAOS - Your Orthopaedic Connection. Retrieved June 15, 2011, from 3. Developmental Dysplasia of the Hip. (n.d.). Medical Practice Areas. Retrieved June 15, 2011, from 4. Developmental Dysplasia of the Hip (DDH). (n.d.). Packard Children's Hospital at Stanford LPCH: Northern California Children's Hospital. Retrieved June 15, 2011, from 5. Developmental dysplasia of the hip. (n.d.). Healthcare Center. Retrieved June 15, 2011, from 6. Developmental dysplasia of the hip (DDH) - Clinical Health Topics - Children's Hospital Boston. (n.d.). Children's Hospital Boston. Retrieved June 15, 2011, from 7. Developmental dysplasia of the hip - Overview. (n.d.). University of Maryland Medical Center Home. Retrieved June 15, 2011, from 8. Developmental dysplasia of the hip - PubMed Health. (n.d.). National Center for Biotechnology Information. Retrieved June 15, 2011, from 9. Developmental dysplasia of the hip: MedlinePlus Medical Encyclopedia. (n.d.). National Library of Medicine - National Institutes of Health. Retrieved June 15, 2011, from 46

47 References 10. Fares Haddad, Consultant Orthopaedic Surgeon. (n.d.). Fares Haddad, Consultant Orthopaedic Surgeon. Retrieved June 15, 2011, from Huang, S., Liu, H., & How, S. (1990). Experimental hip dysplasia in the rabbit. J Formos Med Assoc, 89(4), Hip replacement - Wikipedia, the free encyclopedia. (n.d.). Wikipedia, the free encyclopedia. Retrieved June 15, 2011, from Hip dysplasia (human) - Wikipedia, the free encyclopedia. (n.d.). Wikipedia, the free encyclopedia. Retrieved June 15, 2011, from Infant and Child Hip Dysplasia. (n.d.). Internationl Hip Dysplasia Institute. Retrieved June 15, 2011, from Junk, S. (2008). Influence of developmental hip dislocation on femoral head sphericity: experimental study in dogs. Acta of Bioengineering and Biomechanics, 10(4), Ligamentous laxity - Wikipedia, the free encyclopedia. (n.d.). Wikipedia, the free encyclopedia. Retrieved June 15, 2011, from Pearce, A., Richards, R., Milz, S., Schneider, E., & Pearce, S. (2007). Animal Models For Implant Biomaterial Research in Bone: A Review. European Cells and Materials, 13, Potes, J. C., Reis, J. D., Silva, F. C., Relvas, C., Cabrita, A. S., & Simoes, J. A. (2008). The Sheep as an Animal Model in Orthopedic Research. Experimental Pathology and Health Science, 2(1), Raab, P., Lohr, J., & Krauspe, R. (1998). Remodeling of the acetabulum after experimental hip joint dislocation--an animal experiment study of the rabbit. Z Orthop Ihre Grenzqeb, 136(6), Sexton, M. J., & Renshaw, T. S. (n.d.). Developmental Dysplasia of the Hip - Symptoms - MSN Health & Fitness - Kids' Health. MSN Health: Health Articles & News â Fitness Tips & Guide. Retrieved June 15, 2011, from Sponseller, P., & M.D.(pdf). (n.d.). developmental dysplasia dislocation of the hip ddh Johns Hopkins Orthopaedic Surgery. Welcome to Johns Hopkins Orthopaedic Surgery. Retrieved June 15, 2011, from Wheeles, C. R. (n.d.). Developmental Dislocation of the Hip - Wheeless' Textbook of Orthopaedics. Welcome to Wheeless' Textbook of Orthopaedics - Wheeless' Textbook of Orthopaedics. Retrieved June 47 15, 2011, from