Therapeutic efficacy and pharmacokinetics of liposomal-cannabidiol injection: a pilot clinical study in dogs with naturally-occurring osteoarthritis.

Introduction: Osteoarthritis is a common disease in dogs resulting in chronic pain and decreased wellbeing. Common analgesics such as non-steroidal anti-inflammatories may fail to control pain and can produce major adverse effects. Study objectives were to evaluate pharmacokinetics, therapeutic efficacy, and safety of subcutaneous liposomal-cannabidiol (CBD) as an additional analgesic therapy in dogs suffering from naturally-occurring osteoarthritis. Methods: Six such dogs were recruited following ethics approval and owner consent. Dogs were administered a single subcutaneous injection of 5 mg/kg liposomal-CBD. Plasma concentrations of CBD, blood work, activity monitoring collar data, wellbeing questionnaire (owners) and pain scoring (veterinarian) were performed at baseline and monitored up to six weeks following intervention. Data overtime were compared with baseline using linear-regression mixed-effects. P-value was set at 0.05. Results: CBD plasma concentrations were observed for 6 weeks; median (range) peak plasma concentration (Cmax) was 45.2 (17.8-72.5) ng/mL, time to Cmax was 4 (2-14) days and half-life was 12.4 (7.7-42.6) days. Median (range) collar activity score was significantly increased on weeks 5-6; from 29 (17-34) to 34 (21-38). Scores of wellbeing and pain evaluations were significantly improved at 2-3 weeks; from 69 (52-78) to 53.5 (41-68), and from 7.5 (6-8) to 5.5 (5-7), respectively. The main adverse effect was minor local swelling for several days in 5/6 dogs. Conclusion: Liposomal-CBD administered subcutaneously produced detectable CBD plasma concentrations for 6 weeks with minimal side effects and demonstrated reduced pain and increased wellbeing as part of multimodal pain management in dogs suffering from osteoarthritis. Further placebo-controlled studies are of interest.

Determination of Isometric Points in the Stifle of a Dog Using a 3D Model.

OBJECTIVE: The aim of this study was to develop a three-dimensional (3D) model to identify the isometric component of the cranial cruciate ligament (CCL) in dogs. METHODS: A static 3D model of the specimen was generated from a computed tomography scan of the stifle of a dog and a kinematic model was generated from data collected, every 5 degrees from full extension (131 degrees) through 80 degrees of stifle flexion, from four sensors attached to the tibia. Kinematic data were superimposed on the static model by aligning the points of interest, which were defined for both models. This allowed the tibia to rotate and translate relative to the femur based on the kinematic data. The contours of the distal femur and proximal tibia were converted into point clouds and the distance between each point in the femoral point cloud and all the points in the tibial point cloud were measured at each of the 15 positions. The difference between the maximum and minimum distances for each pair of points was calculated, and when it was less than 0.2 mm, points were illustrated as two red dots connected by a line at their locations on the femur and tibia. RESULTS: A total of 3,681 pairs of isometric points were identified and were located at the origin and insertion of the CCL and on the lateral aspect of the stifle. CONCLUSION: Isometric areas are present at the origin and insertion of the CCL and lateral aspect of the stifle. Better understanding of these locations may lead to refinements in techniques to replace the ruptured CCL.

The effect of joint orientation on passive movement of the dog's stifle.

Introduction: The cranial cruciate ligament (CCL) is one of numerous structures which determine the path of the tibia relative to the femur when passively flexing/extending the stifle of the dog. The effect of cutting the CCL on passive motion with the hind limb in different orientations, is unknown. The aim of this study was to describe passive movement of the tibia relative to the femur in dogs, with the hind limb in three different orientations, and with CCL intact and cut. Methods: Ten cadaveric hind limbs were obtained from dogs weighing between 20 kg and 25 kg and prepared for testing in a custom-built joint testing machine. Each hind limb was tested in three different orientations with data collected, using an electromagnetic tracking system, during 2 cycles of flexion/extension with the CCL intact and cut. Each cycle was initiated with the stifle in full extension (0°) and data was collected at 0°, 20°, 30°, 40°, 45°, and 55° of stifle flexion/extension. Results: Flexion of the stifle resulted in caudal translation and internal rotation of the tibia relative to the femur, with cranial translation and external rotation occurring during extension along the identical path. Cutting the cranial cruciate ligament did not result in significant differences in translation or rotation when the stifle was orientated to approximated the standing position of a dog. Discussion: Isometric points at the origin and insertion of the CCL can potentially be identified in CCL deficient stifles using a technique based on passive motion of an intact stifle.

The use of subchondral bone topography to approximate the center of rotation of the elbow joint in dogs.

OBJECTIVES: The aim of this study was to compare the approximate center of rotation in normal and diseased elbows in dogs. STUDY DESIGN: Cross-sectional study SAMPLE POPULATION: Computer tomography scans of nine dogs with unilateral fragmented medial coronoid process (FMCP). METHODS: A board certified radiologist confirmed that each dog had unilateral FMCP, and a normal contralateral elbow. Digital 3D models of all elbow joints were uploaded into a surgical planning software package. Four axes approximating the center of rotation (COR) of elbow joints were generated using five geometric shapes based on subchondral topography of the humeral condyle radius and ulna. Images showing the locations where axes exited the medial and lateral cortex of the humeral condyle were captured and imported into a second software package, for measurement of distances between exit points and the origin of a system of axes. RESULTS: In normal joints 20/27 (74%) axes exited the medial cortex, and 25/27 (93%) axes exited the lateral cortex cranial and distal to the medial and lateral epicondyles, respectively. In diseased joints 22/27 (81%) axes exited medial cortex and 19/27 (70%) axes exited the lateral cortex, caudal and distal to the medial and lateral epicondyles, respectively. CONCLUSION: Based on CT- derived geometry, the COR of elbow affected with FMCP was generally more caudal than normal. CLINICAL SIGNIFICANCE: External landmarks approximating the location of the elbow COR are provided, and while not validated, may assist in planning, creation, and assessment of procedures for FMCP.

Tooth aspiration in two cats following maxillofacial trauma.

Case series summary: Tooth aspiration is a rare occurrence in human medicine, and even more so in veterinary medicine. This report describes two cats that aspirated a tooth (one canine tooth and one premolar tooth) following maxillofacial trauma. One cat presented with dyspnoea, while the other showed no respiratory clinical signs. In both cases diagnosis was reached by obtaining routine thoracic radiographs, and successful retrieval of the teeth was achieved by bronchoscopy. Both cats recovered uneventfully. Relevance and novel information: To our knowledge, this is the first report in the veterinary literature of tooth aspiration into the tracheobronchial tree following maxillofacial trauma. The scope of this case series is to raise awareness that tooth aspiration can occur following maxillofacial trauma and has the potential for serious complications if not diagnosed and treated promptly. Therefore, an oral examination must be performed in every maxillofacial trauma patient and missing teeth should be accounted for, even when respiratory clinical signs are not detected.

Factors affecting publication in peer-reviewed journals of abstracts presented from 2008 to 2012 ACVO meetings.

PURPOSE: To examine variables that affect publication of ACVO meeting abstracts in peer-reviewed journals and compare results to ECVO publication rate (PR). METHODS: Published papers were identified via online searches for abstracts from 2008 to 2012 ACVO/ECVO meetings. Variables analyzed (via Pearson's chi-Squared test) included the following: oral presentation/poster, type of abstract (clinical/basic science/case report), species, ocular tissue, nationality, funding, first/last/any author a diplomate, resident as first author, and author affiliation (private practice/university). RESULTS: One hundred and eighty-six of 577 ACVO abstracts were published within 608 ± 479 days, with 103 published in Veterinary Ophthalmology. Significant factors included the following: nationality of first/last authors (P = .005); English as first language (P < .001); presentation type (P < .001, oral 40% PR, poster 22% PR); type of study (P = .037, clinical study 35% PR, basic science 30% PR, case report 16% PR); resident as first author (P < .001); diplomate as any author except first/last (P < .001); first author affiliation (P = .001, university 37% PR, practice 21% PR); last author affiliation (P = .003, university 36% PR, practice 22% PR); and species (P < .001, horses 53% PR, multiple species 50% PR, cats 35% PR, food animals 31% PR, exotics/wildlife 31% PR, dogs 27% PR, laboratory animals/in vitro 24%). Nonsignificant factors were as follows: diplomate as first/last author, funding, and ocular tissue. Presentation type, resident as first author, university affiliation of first author, and species had the greatest effect on publication probability. For the same period, ECVO PR was 87 of 299, which was not significantly different from ACVO PR (P = .342). CONCLUSION: At 32%, ACVO PR for the study years is similar to ECVO PR of 29%.

Factors affecting peer-reviewed publication of abstracts presented at meetings of the European College of Veterinary Ophthalmologists (2008-2012).

PURPOSE: To review abstracts presented at five consecutive meetings of the European College of Veterinary Ophthalmologists (ECVO), and identify abstract characteristics that affect the probability of their publication in peer-reviewed journals. METHODS: An online search was conducted for peer-reviewed publications (PRPs) stemming from abstracts from five ECVO meetings (2008-2012). Time to publication and journal were noted. Effects of ocular tissue/discipline, species, type of presentation and study, funding acknowledgment and affiliation, professional qualifications, and nationality of the first and last authors on probability of publication were analyzed. RESULTS: Of presented abstracts, 29% (87/299) were published as PRPs in Veterinary Ophthalmology (n = 50), other veterinary journals (n = 22), and nonveterinary journals (n = 15). During the 5 years studied, there was no significant difference between the impact factor of Veterinary Ophthalmology and the 25 other journals in which PRPs were published (P = 0.369). Median time to PRP acceptance or publication was 468 days. Independent variables most significant in determining the probability of PRP were oral presentation (P = 0.002), resident authorship (P < 0.0001), and species (P = 0.002), with food animal abstracts having the highest odds ratio. Ocular tissue/discipline (P = 0.13) and type of study (P = 0.33) did not affect publication probability. Funding acknowledgment (P = 0.02), author nationality (P = 0.02), and academic affiliation (P = 0.04) were also significant factors. CONCLUSIONS: Publication rate of ECVO abstracts is lower, but time to publication is similar, compared with most biomedical meetings.