Didier Fau

Prevalence of hip dysplasia according to official radiographic screening, among 31 breeds of dogs in France - A retrospective study

In order to determine the prevalence of hip dysplasia (HD) from radiographs that were submitted for authorative grading, and its changes over the time in 31 breeds of dogs in France, a 14 year-retrospective study was conducted. Significant differences were observed between breeds, with HD prevalence ranging from 59.7% (Cane Corso) to 3.9% (Siberian Husky). When comparing the 1993-1999 with the 2000-2006 period in 15 breeds, a significant decrease in HD prevalence was detected in Berger Picard, Bernese Mountain dog, Briard, Gordon Setter, White Swiss Sheepdog and Rottweiler. Modifications observed in the other breeds were not statistically significant.

Transiliac Approach for Exposure of Lumbosacral Intervertebral Disk and Foramen: Technique Description

OBJECTIVE To describe and evaluate a transiliac approach to the L7-S1 disk and intervertebral foramen in dogs. STUDY DESIGN Cadaver study. ANIMALS Fresh canine cadavers (n=10). METHODS A craniolateral approach was made to each iliac wing of 10 fresh canine mixed breed cadavers. An 18 mm hole was drilled in a standardized position through the iliac wing. The musculature connected to the cranial aspects of the sacral wing was dissected and retracted cranially through this iliac window. Endoscopic exploration of the area was performed. RESULTS The foramen and intervertebral disk were clearly observed in all specimens without iatrogenic injury of the L7 nerve branch. Access to the foramen was possible in 16 of 20 specimens without excision of the sacral wing; however, it was always partially excised to observe the intervertebral disk which lies more caudally and ventrally. CONCLUSION Transiliac approach to the lumbosacral joint allows direct exposure of the intervertebral disk and foramen through an iliac window. Endoscopic exploration provided good observation of the intervertebral disk and/or foramen. CLINICAL RELEVANCE Transiliac approach could be used for lateral corpectomy and foraminotomy in dogs with degenerative lumbosacral stenosis caused by ventral or ventrolateral disk protrusion, foramen stenosis, or OCD of the L7-S1 joint. Clinical study will be necessary to evaluate the efficacy of this approach.

Endoscope‐Assisted Thoracolumbar Lateral Corpectomy

OBJECTIVE To report an endoscope-assisted lateral approach to expose the intervertebral foramen and disk and perform lateral corpectomy of thoracolumbar disks in dogs. STUDY DESIGN Cadaver study. ANIMALS Fresh canine cadavers (n=6). METHODS A thoracic (T10-T11) and a lumbar (L3-L4) lateral approach were made on 6 fresh canine mixed breed cadavers. Through a limited skin incision, musculature was dissected and retracted using a neurosurgical self-retaining retractor and lateral corpectomy performed. The approach and bone removal, both performed under endoscopic control, were assessed. RESULTS The foramen and intervertebral disk were clearly observed in all specimens without any iatrogenic injury of the ventral and dorsal nerve branches. Access to the foramen was possible in all specimens; in the thoracic area the head of the rib was always partially excised to observe the intervertebral disk medially. Lateral corpectomy was easily performed in all cadavers and spinal cord observation was good. Extension to foraminotomy or mini hemilaminectomy could easily be performed through the same limited approach. CONCLUSION Endoscopic exploration provided a good viewing of the intervertebral disk and/or foramen. An endoscope-assisted thoracolumbar lateral corpectomy could effectively be performed through a limited approach to the thoracolumbar disks and allowed good ventral spinal cord assessment.

Canine hip dysplasia radiographic screening. Prevalence of rotation of the pelvis along its length axis in 7,012 conventional hip extended radiographs

The prevalence of rotation of the pelvis along its length axis was noted, as was the number of rotations towards the right or left hand side of the dog, on 7,012 conventional hip extended radiographs, which were sent for official screening. 29.8% of the radiographs showed a rotation the pelvis. The rotation was statistically more frequent towards the left hand side of the dog. The number of rejected radiographs for too important pelvis rotation was only 5.2%. The consequences of the pelvis rotation on the Norberg-Olsson angle, on the dorsal femoral head coverage, and in the aspect of cranial acetabular edge have to be taken into account when scoring the dog for hip dysplasia.

Radiographic assessment of the femorotibial joint of the CCLT rabbit experimental model of osteoarthritis

BackgroundThe purposes of the study were to determine the relevance and validity of in vivo non-invasive radiographic assessment of the CCLT (Cranial Cruciate Ligament Transection) rabbit model of osteoarthritis (OA) and to estimate the pertinence, reliability and reproducibility of a radiographic OA (ROA) grading scale and associated radiographic atlas.MethodsIn vivo non-invasive extended non weight-bearing radiography of the rabbit femorotibial joint was standardized. Two hundred and fifty radiographs from control and CCLT rabbits up to five months after surgery were reviewed by three readers. They subsequently constructed an original semi-quantitative grading scale as well as an illustrative atlas of individual ROA feature for the medial compartment. To measure agreements, five readers independently scored the same radiographic sample using this atlas and three of them performed a second reading. To evaluate the pertinence of the ROA grading scale, ROA results were compared with gross examination in forty operated and ten control rabbits.ResultsRadiographic osteophytes of medial femoral condyles and medial tibial condyles were scored on a four point scale and dichotomously for osteophytes of medial fabella. Medial joint space width was scored as normal, reduced or absent. Each ROA features was well correlated with gross examination (p < 0.001). ICCs of each ROA features demonstrated excellent agreement between readers and within reading. Global ROA score gave the highest ICCs value for between (ICC 0.93; CI 0.90-0.96) and within (ICC ranged from 0.94 to 0.96) observer agreements. Among all individual ROA features, medial joint space width scoring gave the highest overall reliability and reproducibility and was correlated with both meniscal and cartilage macroscopic lesions (rs = 0.68 and rs = 0.58, p < 0.001 respectively). Radiographic osteophytes of the medial femoral condyle gave the lowest agreements while being well correlated with the macroscopic osteophytes (rs = 0.64, p < 0.001).ConclusionNon-invasive in vivo radiography of the rabbit femorotibial joint is feasible, relevant and allows a reproducible grading of experimentally induced OA lesion. The radiographic grading scale and atlas presented could be used as a template for in vivo non invasive grading of ROA in preclinical studies and could allow future comparisons between studies.

Risk of simultaneous phenotypic expression of hip and elbow dysplasia in dogs: a study of 1,411 radiographic examinations sent for official scoring.

In order to look for phenotypic correlation between hip (HD) and elbow (ED) dysplasia, we used radiographic scoring obtained from 1,411 dogs of different breeds, which were evaluated for authoritative grading of both conditions. In this population, we found that the risk ratio for an animal to be simultaneously affected by HD and ED is 1.67. For a dog with ED, the risk ratio to be affected by HD increases as the ED grade increases. Similarly, for a dog affected by HD, the risk ratio to be affected by ED increases as the HD grade increases. In a dog affected by HD or ED, the clinician should look for the second condition in the same animal. Due to the low, yet positive correlation, selection against one trait will not affect the other trait sufficiently. Therefore selection has to be conducted at reduction of HD as well as reduction of ED.

Thoracic bite trauma in dogs and cats: a retrospective study of 65 cases

OBJECTIVES To report a case series of thoracic bite trauma in dogs and cats and to evaluate risk factors for mortality. METHODS A retrospective study concerning thoracic bite wounds in dogs and cats was performed. Lesions were categorized by depth of penetration: no wound, superficial, deep or penetrating. Thoracic radiographic reports were reviewed. Lesion management was classified as non-surgical, wound exploration, or explorative thoracotomy. RESULTS Sixty-five cases were collected. Twenty-two percent of patients with normal respiratory patterns showed thoracic radiographic lesions. Respiratory distress was not correlated with mortality. Twenty-eight patients were presented with superficial wounds and 13 with deep wounds. Eight patients exhibited penetrating wounds. Radiographic lesions were observed in 77% of dogs and 100% of cats. Explorative thoracotomy was performed in 28% of patients, and surgical wound exploration in 17.2%. With the exception of skin wounds, thoracic wall discontinuity was the most frequent lesion. Thoracotomy was associated with increased length of hospitalisation but was not correlated with mortality. The mortality rate was 15.4%. No studied factor correlated with mortality, and the long-term outcomes were excellent. CLINICAL SIGNIFICANCE A penetrating injury, more than three radiographic lesions, or both together seemed to be indicative of the need for a thoracotomy. In the absence of these criteria, systematic bite wound explorative surgery is recommended, with extension to thoracotomy if thoracic body wall disruption is observed.

Comparison of radiographic measurements of the patellar tendon-tibial plateau angle with anatomical measurements in dogs. Validity of the common tangent and tibial plateau methods.

OBJECTIVE To evaluate the validity of the common tangent and conventional tibial plateau angle methods for measuring the patellar tendon angle (PTA) in dogs. METHODS Radiographs of cadaveric stifles (n = 20) placed at 135° in true lateral position were obtained to measure the PTA with both methods. A Kirschner wire was inserted perpendicularly to the patellar tendon at its insertion on the tibia and the stifle was dissected. Two Kirschner wires were then used to identify the anatomical landmarks of the tibial plateau. A digital image was obtained of the proximal tibia in true lateral position. Six blinded observers measured each PTA digitally while the anatomical PTA was determined by an independent blinded observer from the angle between the line representing the tibial plateau and the Kirschner wire representing the perpendicular to the patellar tendon. The agreement between the methods was determined statistically from an intraclass correlation coefficient (ICC). RESULTS The global ICC for the common tangent method (0.44) and for the conventional method (0.4) indicated that their overall validity is poor. The measurements obtained by common tangentmethod and conventional method were respectively below and above the anatomical measurements. The reproducibility of the PTA measurements based on images of the dissected stifles was very good. CLINICAL SIGNIFICANCE Both the common tangent and conventional methods show poor concordance with the anatomical measurement of PTA. Further studies are needed to determine if errors in measurements affect the clinical outcome.

Hip dysplasia in dogs: correlation between clinical lameness score, radiographic findings and walkway gait analysis

Hip dysplasia is a frequent degenerative disease, leading to hip osteoarthritis and functional disabilities. Its diagnosis requires a combination of orthopaedic and radiographic findings. Despite the close relationship between X-Ray and hip dysplasia diagnosis, previous studies showed that the clinical examination was not correlated with radiographic hip dysplasia assessment. Moreover, objective gait analysis data obtained from kinetic and kinematic devices seemed to be not significantly correlated with radiographic lesions. Pressure walkway systems have never been used to qualify and quantify this affection. The aim of this study was to provide objective gait analysis and to look for correlation between lameness score, Fédération Cynophilique Internationale (FCI) grading and gait data.

Computed tomography morphometric analysis of porcine spinal growth for scoliosis model development

Scoliosis is a 3D deformity of the spine resulting in aesthetic and functional discomfort, sometimes leading to respiratory insufficiency due to abnormal thoracic cage development (Canavese and Dimeglio 2013). The pig appears to be a suitable animal model for early-onset scoliosis without chest wall insult (Odent et al. 2011), and for preclinical testing of fusionless scoliosis correction device (Roth et al. 2013). Such a model could be an interesting tool to study the growth process in scoliosis deformity. However, limited data are available for the size and the growth potential in the reported models (Odent et al. 2011). The purpose of this study was to define porcine spinal growth using computed tomography (CT) in order to determine spinal growth potential.