RADIOLOGICAL COMPARISON OF LUMBOSACRAL ANATOMY BETWEEN GERMAN AND BELGIAN SHEPHERD (MALINOIS) WORKING DOGS

摘要

The objective of this study was to assess the radiologic differences and the incidence of clinical and radiological signs of degenerative lumbosacral stenosis (DLSS) in 36 active working dogs; 24 German Shepherd (GSDs) and 12 Belgian Shepherd (Malinois; MNs). The medical record was evaluated and pertinent historical data recorded. Thorough clinical and neurological examinations were performed, as well as plain and contrast radiography (myelography) of caudal lumbal and sacral vertebrae. Thirty-three (92%) dogs were able to perform their duties without restrictions. Three (8%) dogs were excluded from active duty due to DLSS (2 dogs) or thoracolumbar disc disease (1 dog). Sixteen GSDs showed clinical signs of DLSS, and the most consistent finding was lower back pain (15 of 16; 94%). Radiological signs of DLSS were confirmed in 10 of them. The differences between GSDs and MNs were found in the bodyweight (GSDs>MNs; p<0.001) and anatomical conformation of the lumbosacral area, which was correlated with the incidence of DLSS. GSDs had significantly higher bodies of L7 (p<0.001) and S1 (p<0.01), higher L7/S1 step (p<0.01) and shorter CrS1/SL distance (p<0.05) than MNs. There was a significant association between DLSS and spondylosis deformans (p<0.05) and sclerosis of S1 cranial endplate (p<0.05). In MNs, no dog was radiographically confirmed for DLSS, although the age of dogs of both breeds was comparable. Fewer eventual radiological changes of the lumbosacral spine were also found in MNs. Regarding our findings, MNs seem to be more suitable for working dogs. The limitations of our study are the small number of MNs and the lack of MNs with DLSS. Our study confirmed radiographic differences of the lumbosacral junction between GSDs and MNs. Nevertheless, we could not confirm any radiographic parameter as a predisposing sign.