Introduction

• Canine hip dysplasia (CHD) Hip: dysplasia is the most common, heritable orthopedic disease in the dog. It is particularly prevalent in large to giant breed dogs (Priester W H, 1972; Riser W H, 1974; Lust G, 1997).
• CHD was first described in 1937 (Schnelle G B) and the disease has been a challenge in diagnosis and treatment for veterinarians and breeders ever since. The first program for the control of hip dysplasia was established in Sweden in 1958, and since then, many countries, including the UK, have established national scoring systems based on radiographs of the coxofemoral joints (Morgan J P et al, 2000).
• Basis of traditional CHD control programs is mainly a subjective assessment of femoral head subluxation and the degree of degenerative joint disease (DJD) on ventrodorsal (VD) pelvic radiographs with the hips in an extended position.
• Problems with these traditional scoring systems are the subjectivity of the assessment and that DJD commonly only occurs in the later stages of the disease. The inclusion of quantitative measurements of the degree of subluxation (Norberg angle) has partially addressed this issue.
• In the 1980s, Dr. Gail Smith, a veterinary orthopedic surgeon and bioengineer, and his colleagues from the University of Pennsylvania School of Veterinary Medicine, developed a new scientific method for the early diagnosis of CHD based on joint laxity. This resulted in a program, called PennHIP® (University of Pennsylvania Hip Improvement Program), which has been available for veterinarians and breeders since 1993.

What is PennHIP®?

Scientific evidence

Advantages and disadvantages

Conclusions

Further Reading

Publications

Refereed papers

• Recent references from PubMed and VetMedResource.
• Kapatkin A S, Gregor T P, Hearon K et al (2004) Comparison of two radiographic techniques for evaluation of hip joint laxity in 10 breeds of dogs. JAVMA 224 (4), 542-546 PubMed.
• Flock A, Kramer M et al (2003) Sonographic examination of the hip joint in dogs measured in a weight-bearing position with radiography and computed tomography. Tierarztliche Praxis 31, 82-91.
• Orlerth S, Busato A, Rauch M et al (2003) Comparison of three distraction methods and conventional radiography for early diagnosis of canine hip dysplasia. JSAP 44 (12), 524-529 PubMed.
• Kapatkin A S, Fordyce H H, Mayhew P D et al (2002) Canine hip dysplasia: the disease and its diagnosis. Comp Cont Educ Pract Vet 24 (7), 526-538 VetMedResource.
• Kapatkin A S, Mayhew P D, Smith G K (2002) Canine hip dysplasia: evidence-based treatment. Comp Cont Educ Pract Vet 24 (8), 590-599 VetMedResource.
• Kapatkin A S, Mayhew P D, Smith G K (2002) Genetic control of canine hip dysplasia. Comp Con Educ Pract Vet 24 (9), 681-687 VetMedResource.
• Renberg W C, Hoskinson J (2001) A method for visualizing the dorsal acetabular rim and the coverage of the femoral head. Veterinary & Comparative Orthopaedics & Traumatology 14 (3), 151-155 VetMedResource.
• Smith G K, Mayhew P D, Kapatkin A S et al (2001) Evaluation of risk factors for degenerative joint disease associated with hip dysplasia in German Shepherd Dogs, Golden Retrievers, Labrador Retrievers, and Rottweilers. JAVMA 219 (12), 1719-1724 PubMed.
• Adams W M, Dueland R T, Daniels R et al (2000) Comparison of two palpation, four radiographic and three ultrasound methods for early detection of mild to moderate canine hip dysplasia. Veterinary Radiology & Ultrasound 41 (6), 484-490 PubMed.
• Adams W M (2000) Radiographic diagnosis of hip dysplasia in the young dog. Vet Clin North Am Small Anim Pract 30 (2), 267-280 PubMed.
• Puerto D A, Smith G K, Gregor T P et al (1999) Relationships between results of the Ortolani method of hip joint palpation and distraction index, Norberg angle, and hip score in dogs. JAVMA 214 (4), 497-501 PubMed.
• Adams W M, Dueland R T, Meinen J et al (1998) Early detection of canine hip dysplasia: comparison of two palpation and five radiographic methods. JAAHA 34 (4), 339-347 PubMed.
• Farese J P, Todhunter R J, Lust G et al (1998) Dorsolateral subluxation of hip joints in dogs measured in a weight-bearing position with radiography and computed tomography. Vet Surg 27 (5), 393-405 PubMed.
• Langenbach A, Green P, Giger U et al (1998) Relationship between degenerative joint disease and hip joint laxity by use of distraction index and Norberg angle measurement in a group of cats. JAVMA 213 (10), 1439-1443 PubMed.
• Smith G K, Hill C M, Gregor T P et al (1998) Reliability of the hip distraction index in two-month-old German Shepherd Dogs. JAVMA 212 (10), 1560-1563 PubMed.
• Lust G (1997) An overview of the pathogenesis of canine hip dysplasia. JAVMA 210 (10), 1443-1445 PubMed.
• O'Brien R T, Dueland R T, Adams W C et al (1997) Dynamic ultrasonographic measurement of passive coxofemoral joint laxity in puppies. JAAHA 33 (3), 275-281 PubMed.
• Smith G K, LaFond E, Gregor T P et al (1997) Within- and between-examiner repeatability of distraction indices of the hip joints in dogs. Am J Vet Res 58 (10), 1076-1077 PubMed.
• Smith G K, LaFond E, Heyman S J et al (1997) Biomechanical characterization of passive laxity of the hip joint in dogs. Am J Vet Res 58 (10), 1078-1082 PubMed.
• Smith G K, Popovitch C A, Gregor T P et al (1995) Evaluation of risk factors for degenerative joint disease associated with hip dysplasia in dogs. JAVMA 206 (5), 642-647 PubMed.
• Veit C (1994) The X-ray examination of hip dysplasia of dogs in standing position. Kleintierpraxis 39 (1), 19-22, 24 VetMedResource.
• Lust G, Williams A J, Burton-Wurster N et al (1993) Joint laxity and its association with hip dysplasia in Labrador Retrievers. Am J Vet Res 54 (12), 1990-1999 PubMed.
• Greshake R J, Ackerman N (1993) Ultrasound evaluation of the coxofemoral joints of the canine neonate. Veterinary Radiology & Ultrasound 34 (2), 99-104 VetMedResource.
• Smith G K, Gregor T P, Rhodes W H et al (1993) Coxofemoral joint laxity from distraction radiography and its contemporaneous and prospective correlation with laxity, subjective score, and evidence of degenerative joint disease from conventional hip-extended radiography in dogs. Am J Vet Res 54 (7), 1021-1042 PubMed.
• Lust G, Beilman W T, Rendano V T (1980) A relationship between degree of laxity and synovial fluid volume in coxofemoral joints of dogs predisposed for hip dysplasia. Am J Vet Res 41 (1), 55-60 PubMed.
• Lust G, Farrell P W (1977) Hip dysplasia in dogs: the interplay of genotype and environment. Cornell Vet 67 (4), 447-466 PubMed.
• Riser W H (1975) The dog as a model for the study of hip dysplasia. Growth, form, and development of the normal and dysplastic hip joint. Vet Pathol 12 (4), 234-334 PubMed.
• Riser W H (1974) Canine hip dysplasia: cause and control. JAVMA 165 (4), 360-362 PubMed.
• Priester W H, Mulvihill J J (1972) Canine hip dysplasia: relative risk by sex, size, and breed, and comparative aspects. JAVMA 160 (5), 735-739 PubMed.
• Henricson B, Norberg I, Olsson S E (1966) On the etiology and pathogenesis of hip dysplasia: a comparative review. JSAP 7 (11), 673-688 PubMed.
• Schnelle G B (1937) Congenital subluxation of the coxofemoral joint in a dog. University of Pennsylvania Bulletin 65, 15.

Other sources of information

• Smith G K (2004) Letter to the editor: Value before cost when screening for canine hip dysplasia. JSAP 45, 273-274.
• Morgan J P, Audell L, Paatsama S et al (2000) Schemes for control of disease. In: J P Morgan, A Wind & A P Davidson (eds). Hereditary bone and joint disease in the dog. Hanover: Schluetersche. pp 253-310.