Thoracic Limb Angular Deformity in Chondrodystrophic Dogs: Repeatability of Goniometric Measurement of External Rotation and Carpal Valgus

Abstract

Objective We aimed to provide repeatable methods for quantifying antebrachial valgus and rotation in dogs with and without complex angular deformities. Thus, we investigated the repeatability of two methods to measure carpal valgus and one method to measure external rotation of the thoracic limb in a standing position. Study Design This was a prospective observer agreement study with a sample of 18 non-chondrodystrophic dogs as baseline and 43 chondrodystrophic dogs. The rotation measurements (ROT), modified valgus measurements (VALG-M), and established carpal valgus measurements (VALG) were done independently by two investigators. Repeatability was assessed with intraclass correlation coefficient (ICC). Results The measured mean (± standard deviation) angles of ROT, VALG-M, and VALG for non-chondrodystrophic dogs were 14 degrees (± 5 degrees), 9 degrees (± 4 degrees), and 4 degrees (± 3 degrees) and 30 degrees (± 13 degrees) and 23 degrees (± 11 degrees) for ROT and VALG-M for chondrodystrophic dogs respectively. In non-chondrodystrophic dogs, ICC was low with mean errors of 1 to 6 degrees, whereas in chondrodystrophic dogs, intra- and intertester ICC was high for ROT and VALG-M with mean errors of 3 to 8 degrees. Conclusion The ROT and VALG-M methods can be used as reliable tools to objectively quantify aspects of thoracic limb alignment for research, clinical, and screening purposes in both non-chondrodystrophic and chondrodystrophic dogs. The mean values of ROT, VALG-M, and VALG can be used as references for non-chondrodystrophic dogs in the standing position.

Breed-typical front limb angular deformity is associated with clinical findings in three chondrodysplastic dog breeds

“…The measurements were taken once with the tape measure and included the height at the withers (with the help of a spirit level placed at the highest point of the dorsal border of the scapula), the distance from the ground to the top of the olecranon ( 17 ), and the chest circumference behind the scapulae. Distal limb external rotation (ROT) and carpal valgus (VALG) were measured three times during weight bearing with the dog in a standing position using a universal goniometer according to a protocol described earlier ( 18 ), and the mean of the measurements was used in the statistical analyses. Passive range of motion (PROM) of the carpus, elbow, and shoulder was measured three times with the dog in lateral recumbency by using a universal goniometer as previously described ( 19 ), and the mean of the measurements was used in the statistical analyses.…”