Intra- and Inter-observer Variability of Measurements of the Laxity Index on Stress Radiographs Performed with the Vezzoni-Modified Badertscher Hip Distension Device
06 March 2017
14 February 2018
02 June 2018 (eFirst)
Objectives To describe and evaluate the accuracy, intra- and inter-observer variability of the laxity index (LI), used to quantify hip laxity on stress radiographs obtained with the Vezzoni-modified Badertscher distension device (VMBDD).
Methods Stress radiographs of 10 dogs obtained with the VMBDD were measured three times by an experienced observer. Six participants with different backgrounds (two ECVDI residents, two PhD students, two veterinary assistants) followed a short presentation and performed subsequently the measurements four times in two separate sessions. The effect of self-learning, feedback and specialization on the accuracy of the measurements was assessed.
Results While the intra- and inter-observer variability were in agreement with other studies, the results of the experienced observer indicated that the variability can be very low. Neither feedback nor self-learning improved the results. A high degree of experience in radiographic assessment was not necessary to perform the measurements correctly.
Clinical Significance As the LI measurements were acceptable after a short presentation, they support the use of VMBDD for a complete and correct in-house evaluation of the hip joint by trained clinicians. However, we propose that, in the context of screening, measurements should be performed by a limited number of experienced examiners, to limit the impact of the inter-observer variability.
* Jimmy H. Saunders and Bart J.G. Broeckx authors contributed equally.
- 1 Henricson B, Norberg I, Olsson SE. On the etiology and pathogenesis of hip dysplasia: a comparative review. J Small Anim Pract 1966; 7 (11) 673-688
- 2 Alexander JW. The pathogenesis of canine hip dysplasia. Vet Clin North Am Small Anim Pract 1992; 22 (03) 503-511
- 3 Oberbauer AM, Keller GG, Famula TR. Long-term genetic selection reduced prevalence of hip and elbow dysplasia in 60 dog breeds. PLoS One 2017; 12 (02) e0172918
- 4 Riser WH. A half century of canine hip dysplasia. Semin Vet Med Surg (Small Anim) 1987; 2 (02) 87-91
- 5 Powers MY, Karbe GT, Gregor TP. , et al. Evaluation of the relationship between Orthopedic Foundation for Animals' hip joint scores and PennHIP distraction index values in dogs. J Am Vet Med Assoc 2010; 237 (05) 532-541
- 6 Badertscher RR. The half-axial position: improved radiographic visualization of subluxation in canine hip dysplasia. Master Thesis, University of Georgia, USA, 1977
- 7 Smith GK, Biery DN, Gregor TP. New concepts of coxofemoral joint stability and the development of a clinical stress-radiographic method for quantitating hip joint laxity in the dog. J Am Vet Med Assoc 1990; 196 (01) 59-70
- 8 Farese JP, Todhunter RJ, Lust G, Williams AJ, Dykes NL. Dorsolateral subluxation of hip joints in dogs measured in a weight-bearing position with radiography and computed tomography. Vet Surg 1998; 27 (05) 393-405
- 9 Flückiger MA, Friedrich GA, Binder H. A radiographic stress technique for evaluation of coxofemoral joint laxity in dogs. Vet Surg 1999; 28 (01) 1-9
- 10 Broeckx BJG, Vezzoni A, Bogaerts E. , et al. Comparison of three methods to quantify laxity in the canine hip joint. Vet Comp Orthop Traumatol 2018; 31 (01) 23-29
- 11 Vezzoni A, Dravelli G, Corbari A. , et al. Early diagnosis of canine hip dysplasia. Eur J Companion Anim Pract 2005; 15: 173-184
- 12 Ginja MM, Ferreira AJ, Silvestre M, Gonzalo-Orden JM, Llorens-Pena MP. Repeatability and reproducibility of distraction indices in PennHIP examinations of the hip joint in dogs. Acta Vet Hung 2006; 54 (03) 387-392
- 13 Smith GK, Biery DN, Rhodes WH. Between- and within- radiologist accuracy of subjective hip scoring of the ventrodorsal hip-extended radiograph. In: Proceedings of the International Symposium on Hip Dysplasia and Osteoarthritis in Dogs; 1996: 20
- 14 Paster ER, LaFond E, Biery DN. , et al. Estimates of prevalence of hip dysplasia in Golden Retrievers and Rottweilers and the influence of bias on published prevalence figures. J Am Vet Med Assoc 2005; 226 (03) 387-392
- 15 Verhoeven G, Coopman F, Duchateau L, Saunders JH, van Rijssen B, van Bree H. Interobserver agreement in the diagnosis of canine hip dysplasia using the standard ventrodorsal hip-extended radiographic method. J Small Anim Pract 2007; 48 (07) 387-393
- 16 Malm S, Fikse F, Egenvall A. , et al. Association between radiographic assessment of hip status and subsequent incidence of veterinary care and mortality related to hip dysplasia in insured Swedish dogs. Prev Vet Med 2010; 93 (2-3): 222-232
- 17 Smith GK, Popovitch CA, Gregor TP, Shofer FS. Evaluation of risk factors for degenerative joint disease associated with hip dysplasia in dogs. J Am Vet Med Assoc 1995; 206 (05) 642-647
- 18 Runge JJ, Kelly SP, Gregor TP, Kotwal S, Smith GK. Distraction index as a risk factor for osteoarthritis associated with hip dysplasia in four large dog breeds. J Small Anim Pract 2010; 51 (05) 264-269
- 19 Todhunter RJ, Grohn YT, Bliss SP. , et al. Evaluation of multiple radiographic predictors of cartilage lesions in the hip joints of eight-month-old dogs. Am J Vet Res 2003; 64 (12) 1472-1478
- 20 Leighton EA. Genetics of canine hip dysplasia. J Am Vet Med Assoc 1997; 210 (10) 1474-1479
- 21 Ginja MM, Silvestre AM, Ferreira AJ. , et al. Passive hip laxity in Estrela Mountain Dog--distraction index, heritability and breeding values. Acta Vet Hung 2008; 56 (03) 303-312
- 22 Zhang Z, Zhu L, Sandler J. , et al. Estimation of heritabilities, genetic correlations, and breeding values of four traits that collectively define hip dysplasia in dogs. Am J Vet Res 2009; 70 (04) 483-492