Evaluation of subchondral bone cysts in canine elbows with radiographic osteoarthritis secondary to elbow dysplasia.

OBJECTIVE: To investigate whether subchondral bone cysts (SBCs) were present in dogs with radiographic elbow osteoarthritis (OA) and to investigate their relationship with radiographic OA severity. STUDY DESIGN: Retrospective cross-sectional study. SAMPLE POPULATION: Thirty-eight Labrador retrievers (total of 76 elbows). METHODS: Elbow computed tomography (CT) images of 18 young (≤2 years old) and 20 old (>2 years old) Labrador retrievers, which presented for elbow-associated lameness, were reviewed. Radiographic elbow OA was graded into four groups based on the largest osteophyte size on CT. The presence, number, and maximum diameter of SBCs were determined. RESULTS: Subchondral bone cysts were only identified in elbows with osteophytic new bone formation. The number and size of SBCs were associated with radiographic OA severity (p < .001 and p = .041 respectively). Specifically, the rate at which SBCs were present increased for both moderate and severe OA in comparison with the mild OA (moderate OA RR = 2.46, 95% CI 2.08-2.92, p < .001; severe OA RR = 5.60, 95% CI 4.79-6.55, p < .001). For dogs with severe OA, there was an increased likelihood that their SBCs were larger than SBCs from dogs with mild OA (OR = 1.056, 95% CI 1.012-1.101, p = .012). No SBCs were observed in elbows without radiographic evidence of OA. CONCLUSION: Subchondral bone cysts were identified as a feature of radiographic elbow osteoarthritis in Labrador retrievers, and their number and size were indicative of the presence and severity of radiographic elbow OA. CLINICAL SIGNIFICANCE: Subchondral bone cysts are a potential imaging biomarker for quantitative assessment for canine OA.

Risk Factors Associated with Plantar Necrosis following Tarsal Arthrodesis in Dogs.

OBJECTIVES: The aim of this study was to define landmarks of the intermetatarsal channel of the dorsal pedal artery and to assess whether damage to the dorsal pedal artery during metatarsal screw placement in dogs undergoing pan- and partial-tarsal arthrodesis (PanTA/ParTA) could be a mechanism in the development of plantar necrosis. STUDY DESIGN: This study was divided in to two parts: (1) ex-vivo anatomical study: 19 canine cadavers, (2) retrospective clinical study: 39 dogs. Cadaveric dissection documented the mean intermetatarsal channel position. Metatarsal screw position was evaluated on postoperative radiographs of dogs after PanTA or ParTA. Screw position, arthrodesis type and surgical approach were assessed for their impact on complications, including plantar necrosis. RESULTS: The mean proximal and distal extent of the intermetatarsal channel lies between 4.3% ± 1.9 and 22.8% ± 2.9 the length of metatarsal III (MTIII) respectively. The intermetatarsal channel lies within the most proximal 25% of MTIII in 95% of cases. At least one screw risked damaging the mean intermetatarsal channel position in 92% of dogs; 8% of these dogs went on to develop plantar necrosis. The mean screw position did not differ between ParTA cases with or without plantar necrosis (p > 0.05). CONCLUSION: Violation of the intermetatarsal channel is possible during metatarsal screw placement. Care should be taken when placing screws in the proximal 25% of the metatarsals, specifically avoiding exiting dorsally between MTII and MTIII and across the distal region of the intermetatarsal channel, where the perforating metatarsal artery passes interosseously, as damage may contribute to the aetiology of plantar necrosis.

Feline Femoral Fracture Fixation: What are the options?

PRACTICAL RELEVANCE: The femur is the most commonly fractured bone in cats. Femoral fractures usually result from high-velocity trauma such as a road traffic accident or fall from a height and, as such, are associated with a wide variety of concurrent injuries. The initial focus of treatment should always be on assessment and stabilisation of the major body systems. Once any concurrent injuries have been addressed, all femoral fractures need surgical stabilisation, with the notable exception of greenstick fractures in very young cats, which can heal with cage rest alone. A number of different surgical options are available depending on the fracture type, location, equipment, surgeon experience and owner finances. CLINICAL CHALLENGES: Femoral fractures can vary hugely in complexity and the small size of feline bones can limit the choice of implants. Furthermore, cats can present unique challenges in the postoperative period due to their active nature and the limited means to control their exercise level. AUDIENCE: This review is aimed at general and feline-specific practitioners who have some experience of feline orthopaedics, as well as those simply wishing to expand their knowledge. AIMS: The aim of this review is to help clinicians assess, plan and manage feline femoral fractures. It provides an overview of diagnostic imaging and a discussion of a range of suitable surgical options, including the principles of different types of fixation. It also highlights cat-specific issues, approaches and implants pertinent to the management of these cases. EVIDENCE BASE: A number of original articles and textbook chapters covering many aspects of femoral fractures in cats and dogs have been published. Where possible, this review draws on information from key feline research and, where necessary, extrapolates from relevant canine literature. The authors also offer practical guidance based on their own clinical experience.

Moving Beyond the Limits of Detection: The Past, the Present, and the Future of Diagnostic Imaging in Canine Osteoarthritis.

Osteoarthritis (OA) is the most common orthopedic condition in dogs, characterized as the chronic, painful end-point of a synovial joint with limited therapeutic options other than palliative pain control or surgical salvage. Since the 1970s, radiography has been the standard-of-care for the imaging diagnosis of OA, despite its known limitations. As newer technologies have been developed, the limits of detection have lowered, allowing for the identification of earlier stages of OA. Identification of OA at a stage where it is potentially reversible still remains elusive, however, yet there is hope that newer technologies may be able to close this gap. In this article, we review the changes in the imaging of canine OA over the past 50 years and give a speculative view on future innovations which may provide for earlier identification, with the ultimate goal of repositioning the limit of detection to cross the threshold of this potentially reversible disease.

Computed Tomographic Features of Non-Lame French Bulldog Elbows.

OBJECTIVE: French Bulldogs are predisposed to humeral condylar fractures. Computed tomography (CT) in English Springer Spaniel elbows has allowed identification of humeral intracondylar fissures (HIF), which can cause lameness and predispose to condylar fractures. This study aimed to evaluate CT characteristics of non-lame French Bulldog elbows, to determine the presence of underlying elbow disease. STUDY DESIGN: Retrospective evaluation of CT images from elbows of non-lame French Bulldogs from scans obtained for soft tissue or neurological evaluation was performed. Images were evaluated for the presence of HIF and other elbow abnormalities: condylar and supracondylar remodelling, humeral condylar sclerosis, elbow incongruency, medial coronoid process disease and elbow osteoarthritis. Descriptive statistics were performed. RESULTS: Computed tomographic scans from 37 dogs (74 elbows) were reviewed. No HIF were identified, although 28/74 elbows had an intracondylar sclerotic band. Medial coronoid process disease was noted in 16/74 elbows, and small osteophytes were present in 21/74 elbows, suggesting a degree of subclinical elbow disease. Widening of the caudolateral aspect of the radial incisure was identified (37/74) as a breed normal. Elbow incongruency was otherwise rare. CONCLUSION: Non-lame French Bulldogs showed a low prevalence of occult elbow disease but a proportion had radial incisure widening. Although humeral intracondylar sclerosis was present in over a third of dogs, no HIF were identified and therefore no clear cause for their increased risk of humeral condylar fracture was identified.

CT characterisation and classification of feline temporomandibular joint trauma: a case series of 79 cats.

OBJECTIVES: The aim of this study was to characterise and describe patterns of temporomandibular joint (TMJ) injuries occurring in cats using CT. METHODS: A cross-sectional study was carried out in adherence with the STROBE guidelines. Among the medical and CT records of 79 cats, 158 TMJs were reviewed in a collaborative study between six institutions. RESULTS: TMJ injuries were most commonly unilateral, representing 70.9% of cases. The mandibular condyle was fractured in 88 cases (55.7%) of the 158 TMJs observed. Of those, 84.0% were intra-articular condyle fractures, with the medial half of the mandibular condyle over-represented. Luxations occurred in 32.9% of cases, which was 19.0% of all evaluated TMJs. Rostrodorsal luxations were most common representing 87.0% of all luxations. Temporal bone fractures were observed in 30.4% of all cases, which was 18.4% of TMJs. The majority of fractures were of an unknown cause. When the cause was determined, road traffic accident (RTA) was the most frequent, followed by animal interaction, other external forces (sharp or blunt force) and high-rise trauma. Bilateral injuries were 13.1 times more likely to occur in high-rise trauma (P = 0.01) and temporal bone fracture was significantly associated with RTAs (P = 0.016). No other significant associations were observed between cause of injury and the resulting TMJ injury pattern. CONCLUSIONS AND RELEVANCE: Various TMJ injury patterns can occur in cats as a result of trauma. Intra-articular fractures of the medial half of the mandibular condyle occur most commonly. Although unilateral injuries are more frequent, high-rise trauma tends to present with bilateral lesions. Further studies with a larger sample size should be performed to better understand TMJ patterns of injury and how they relate to possible causes.

Traumatic physeal fractures in cats: a review of 36 cases (2010-2020).

OBJECTIVES: The aim of this study was to describe the demography, aetiology, location and classification of physeal fractures in cats, and to describe their management and outcomes. METHODS: Clinical records and radiographs of cats referred for management of physeal fractures were retrospectively reviewed. Fractures of the proximal femoral physis were excluded. Descriptive statistics were used to describe signalment, cause of injury, presence of concurrent injuries, fracture description, treatment modality, complications, follow-up, physeal closure, implant removal and outcome. RESULTS: Thirty-four cats with 36 fractures were included, of which 17 affected the distal femur, 11 the distal tibia and fibula, five the distal radius and ulna, two the proximal tibia and one the distal humerus. Salter-Harris classification was type I in 14, type II in 16, type III in two and type IV in four fractures. Thirty-four fractures were treated with primary fixation, and the most common method was crossed Kirschner wires (24/34 fractures). Complications were observed in 14 fractures, of which 12 were minor. At radiographic follow-up, physeal closure was reported in 23 fractures, of which 15 were considered premature. Implant removal was performed in three fractures. Outcome was good in 28, fair in four and poor in two fractures. CONCLUSIONS AND RELEVANCE: Fracture of the distal femoral physis was the most common physeal fracture seen. Cats presenting with physeal fractures may be skeletally immature or mature with delayed physeal closure. The rate of physeal closure after fracture repair was relatively high but without apparent impact. The frequency of implant removal was very low, indicating that despite having a physeal fracture repair, most cats did not require a second procedure to remove implants. Overall, internal fixation provided a good outcome in most fractures.

Management and Long-Term Outcome of Acetabular Fractures in Dogs: A Retrospective Study of 49 Dogs.

OBJECTIVE: The aim of this study was to categorize the presentation, management, complications and long-term outcome of canine acetabular fractures, and to determine the factors affecting outcome. MATERIALS AND METHODS: Case records and imaging for dogs with acetabular fractures were reviewed with long-term follow-up via canine brief pain inventory (CBPI) and owner questionnaires. RESULTS: The majority of fractures were in the mid-third (36/52) and caudal-third (13/52) with few in the cranial-third of the acetabulum (3/52). Concurrent injuries were diagnosed in 47/49 dogs; 10/34 dogs had neurological deficits on presentation. Forty-seven fractures received treatment: 25/47 had direct surgical repair (DSR), 10/47 had salvage surgery (SS) and 12/47 had conservative management (CM). Fracture location significantly affected treatment group (p = 0.001). New neurological deficits were documented after DSR in 5/24 dogs and SS in 2/10 dogs. Short-term complications occurred after DSR in 10/18 dogs (five minor, five major) and CM in 1/8 dogs (major). Long-term complications occurred after DSR in 2/15 dogs (major) and CM in 2/7 dogs (catastrophic). Conservative management dogs had worse average owner-reported CBPI scores than DSR or SS dogs. CLINICAL SIGNIFICANCE: Acetabular fractures predominate in the mid and caudal acetabulum, with high levels of concurrent injuries. Fracture location significantly influenced the treatment approach taken. Postoperative neurological deficits are common following SS and DSR.

Traumatic joint luxations in cats: Reduce, repair, replace, remove.

PRACTICAL RELEVANCE: Traumatic joint luxations are usually associated with significant trauma and there may be concomitant systemic injury. Joints are unstable as a result of injury to one or more supporting structures and the clinician should aim to determine which structures are damaged with physical examination, diagnostic imaging and careful assessment under sedation/anaesthesia. The aim is to reduce the joint back to its anatomical position, and then to maintain this through repair of damaged structures. However, where this is not possible, replacement or removal (arthrodesis/excision arthroplasty) of the joint remain viable options. CLINICAL CHALLENGES: Owing to the small size of feline joints and the severity of damage often seen, surgical management of these cases can be challenging. The first priority is to ensure the patient is systemically well before embarking on any specific surgical treatment of a luxated joint. Cats also present challenges in the postoperative period and a lack of patient and owner compliance can be detrimental to postoperative outcomes. AIMS: This article aims to help the reader diagnose joint luxations and to assist decision-making with an overview of the management and treatment options available. EVIDENCE BASE: There are a number of original articles and textbook chapters in the literature covering aspects of different joint luxations, particularly for the more common luxations. This article draws on information from key feline research and, where necessary, extrapolates from relevant canine research. The authors also offer practical guidance based on their own clinical experience.

Isolated Articular Fractures of the Canine Talus: Diagnosis and Signalment in Fourteen Dogs.

OBJECTIVE: The aim of this retrospective multicentre case series was to describe signalment, presenting signs and imaging findings in dogs with isolated articular fractures of the talus. STUDY DESIGN: Medical records (2008-2019) of dogs with isolated articular talar fractures were reviewed. RESULTS: Fourteen dogs met the inclusion criteria; affected breeds were four German Pointer (three shorthair and one wirehaired), three Labrador Retrievers, two Rottweilers, two Springer Spaniels, one cross breed, one Greyhound and one Great Münsterländer. The age range was 1 to 8 years with a median of 4.7 years. Lameness was usually acute in onset and had been present for a range of 4 to 540 days prior to referral.The most common fracture configuration involved the lateral trochlear ridge only (n = 9). Two of the fourteen fractures affected both trochlear ridges. Thirteen dogs were initially assessed radiographically with classic orthogonal views, but a fracture was only visible in five cases. The remainder were confirmed with further radiographic projections (n = 4) or computed tomography (n = 5). In one case, the lameness was located to the tarsus by scintigraphy. CONCLUSION: Isolated articular fracture of the talus is rare and may prove a diagnostic challenge due to the varied presentations and complex anatomy of the bone. Pathology of the talus may be suspected in any case of lameness localized to the tarsus and oblique/skyline radiographic views or advanced imaging should be performed if standard radiographic views are unremarkable.

Computed Tomographic Measurement of Trochlear Depth in Three Breeds of Brachycephalic Dog.

OBJECTIVE: The aim of this study was to determine the trochlear sulcus depth of three common brachycephalic breeds at risk of medial patellar luxation. STUDY DESIGN: Retrospective blinded clinical study using a previously validated ratio (T/P) of maximal trochlear sulcus depth (T) and maximal patellar craniocaudal thickness (P) measured on computed tomography, to assess trochlear sulcus depth in Pugs, French Bulldogs and English Bulldogs without clinical patellar luxation. The effect of breed on T/P was assessed using one-way linear regression models. RESULTS: The mean T/P was affected by breed (p < 0.001). There was significant difference between Pugs (0.45) and French Bulldogs (0.38) and between Pugs and English Bulldogs (0.4). There was no significant difference between Pugs and previously published data for non-brachycephalic and mixed breed dogs (0.46) (p = 0.39). Mean T/P was significantly reduced in the brachycephalic dog breeds combined compared with the previously published data (p < 0.001). CONCLUSION: The trochlear sulcus varies by breed and was more shallow in French and English Bulldogs than Pugs, hence a shallow sulcus may be a breed-driven characteristic. The three breeds assessed are at risk of patellar luxation but sulcus depth did not directly correlate with previously published risk factors-the contribution of sulcus depth to the aetiopathogenesis of patellar luxation remains unclear. Trochlear recession to achieve patellar coverage of 50% may be excessive considering maximal breed normal depth.

Epidemiology and clinical management of elbow joint disease in dogs under primary veterinary care in the UK.

BACKGROUND: Conditions affecting the elbow joint are a common cause of lameness in dogs. Primary-care veterinary clinical data are now recognised as a valuable research resource. Using data from the VetCompass Programme, this study aimed to report the frequency and risk factors for elbow joint disease in dogs under primary veterinary care in the UK and describe clinical management. RESULTS: From 455,069 dogs under veterinary care, the one-year period prevalence for elbow joint disease diagnosis was 0.56% (95% CI: 0.53-0.60). Of 616 incident cases, the most common specific variants of elbow joint disease were osteoarthritis (n = 468, 75.97%), elbow dysplasia (190, 30.84%) and traumatic (41, 6.66%). The most common signs described by the owners were lameness (n = 466, 75.65%), difficulty exercising (123, 19.97%) and pain (86, 13.96%). The most common findings recorded on veterinary examination were pain (n = 283, 45.94%), lameness (278, 45.13%) and reduced range of movement (243, 39.45%). Common medications used included non-steroidal anti-inflammatory drugs (n = 544, 88.31%), tramadol (121, 19.64%) and disease modifying agents (118, 19.16%). Of 109 deaths involving euthanasia with information available from the 616 incident cases, elbow joint disease contributed to the decision to euthanase in 45 (41.28%) dogs.Five breeds showed increased odds of elbow joint disease compared with crossbred dogs: Rottweiler (OR: 6.16, 95% CI 3.89-9.75), Labrador Retriever (OR: 5.94, 95% CI 4.65-7.60), German Shepherd Dog (OR: 4.13, 95% CI 2.88-5.93), Golden Retriever (OR: 3.11, 95% CI 1.93-5.00) and English Springer Spaniel (OR: 2.00, 95% CI 1.26-3.18). Additional risk factors included having an adult bodyweight that was equal or higher than their breed/sex mean, advancing age, being male, being neutered, being insured and larger bodyweight. CONCLUSIONS: Elbow joint disease is a relatively common diagnosis in dogs and has a high welfare impact as evidenced by the high proportion of cases recorded with pain, lameness and analgesic therapy. There are strong breed predispositions, in particular for large breed dogs. These findings present a clear case for improved breeding programmes to reduce the burden of elbow joint disease.

Risk Factors for Canine Osteoarthritis and Its Predisposing Arthropathies: A Systematic Review.

Osteoarthritis is a common clinical and pathological end-point from a range of joint disorders, that ultimately lead to structural and functional decline of the joint with associated lameness and pain. Increasing understanding of the risk factors associated with osteoarthritis will assist in addressing the significant threat it poses to the welfare of the dog population and implementing preventive measures. Presented here, is the first comprehensive systematic review and evaluation of the literature reporting risk factors for canine osteoarthritis. This paper aimed to systematically collate, review and critically evaluate the published literature on risk factors for canine osteoarthritis and its predisposing conditions such as developmental joint dysplasias, cruciate ligament degeneration, and patellar luxation. Peer-reviewed publications were systematically searched for both osteoarthritis and predisposing arthropathies on Web of Science and PubMed following PRISMA (2009) guidelines, using pre-specified combinations of keywords. Sixty-two papers met the inclusion criteria and were evaluated and graded on reporting quality. Identified risk factors included both modifiable factors (neuter status and body weight) for which intervention can potentially affect the risk of occurrence of osteoarthritis, and unmodifiable factors (sex, breed, and age) which can be used to identify individuals most "at risk." Osteoarthritis in dogs frequently develops from predisposing arthropathies, and therefore risk factors for these are also important to consider. Papers evaluated in this study were rated as medium to high-quality; gap analysis of the literature suggests there would be significant benefit from additional research into the interactions between and relative weighting of risk factors. There are a number of examples where research outcomes are conflicting such as age and sex; and further investigation into these factors would be beneficial to attain greater understanding of the nature of these risks. Comprehensively collating the published risk factors for osteoarthritis and its predisposing conditions offers opportunities to identify possible means for control and reduction within the population through preventative methods and control strategies. These factors are highlighted here, as well as current literature gaps where further research is warranted, to aid future research direction.

Impact of breed on canine humeral condylar fracture configuration, surgical management, and outcome.

OBJECTIVE: To report the prevalence, configuration, risk factors, fixation methods and outcomes after repair of humeral condylar fractures (HCF) in dogs. STUDY DESIGN: Retrospective nested cohort study. SAMPLE POPULATION: One hundred twelve dogs. METHODS: Medical records of dogs referred between January 2010 and August 2018 were searched for HCF. Demographics, fracture configuration, repair, and complications were obtained from medical records. Radiographs were assessed for fracture reduction, implant positioning, and bone healing. Short-term radiographic and clinical outcomes, and long-term owner-assessed outcome was determined. Associations between these variables were statistically analyzed. RESULTS: Dogs with HCF represented 112 of 43 325 (0.26%, 95% CI 0.22-0.31) referrals. French bulldogs and spaniel breeds were predisposed to HCF (P < .02). French bulldogs were 6.58 times (95% CI 1.62-26.7) more likely than other breeds to have a medial HCF (P = .008). Epicondylar plate fixation was associated with reduced complications compared with lag screws and Kirschner wires (P = .009). Lameness was scored as 1 of 5 (median) in the 85 dogs with initial follow-up (median 6 weeks) after HCF repair. Outcome was considered excellent in 26 of 31 dogs with long-term follow-up (median 36 months). CONCLUSION: French bulldogs and spaniels were predisposed to HCF, and medial HCF were more common in French bulldogs. Epicondylar plate fixation was associated with reduced complications. CLINICAL SIGNIFICANCE: French bulldogs are predisposed to HCF, including medial HCF. Epicondylar plate fixation is recommended over other epicondylar fixation methods to reduce complications.

Repair of Y-T Humeral Condyle Fractures with Locking Compression Plate Fixation.

OBJECTIVES: The aim of this study was to describe the use of locking compression plates (LCP) in Y-T humeral condyle fractures and to evaluate their clinical outcome. METHODS: This study involved a retrospective review, including clinical, radiographical and canine brief pain inventory outcome evaluation. RESULTS: Eighteen consecutive dogs met the inclusion criteria, and 15/18 were considered to have humeral intracondylar fissure. Twelve of 18 dogs had simple fractures, and the remaining six had comminuted fractures. Postoperative radiographs revealed accurate intracondylar reconstruction (articular step defect [ASD] < 1 mm) in 17/18 of patients. Short-term outcome was considered fully functional in 9/13 and acceptable in 3/13 patients. Complications were diagnosed in 2/13; infection in one with resolution after antibiotic treatment, and one case of implant failure. Nine of 18 owners provided postoperative questionnaire responses (median 25; range: 14-52 months) and 8/9 clients perceived the treatment to have resulted in an excellent overall outcome. CLINICAL SIGNIFICANCE: Repair of Y-T humeral fractures with LCP allowed for hybrid fixation and monocortical screw placement in distal fracture fragments. There was no significant ASD at the intracondylar fracture line in most cases. ASD using combined medial and lateral approaches depends upon the accuracy of supracondylar reduction, particularly on the side that is reduced and stabilized first, and the use of locking screws may have been influential in minimizing primary loss of reduction, potentially maintaining the initial fragment reduction.

Spontaneous dog osteoarthritis - a One Medicine vision.

Osteoarthritis (OA) is a global disease that, despite extensive research, has limited treatment options. Pet dogs share both an environment and lifestyle attributes with their owners, and a growing awareness is developing in the public and among researchers that One Medicine, the mutual co-study of animals and humans, could be beneficial for both humans and dogs. To that end, this Review highlights research opportunities afforded by studying dogs with spontaneous OA, with a view to sharing this active area of veterinary research with new audiences. Similarities and differences between dog and human OA are examined, and the proposition is made that suitably aligned studies of spontaneous OA in dogs and humans, in particular hip and knee OA, could highlight new avenues of discovery. Developing cross-species collaborations will provide a wealth of research material and knowledge that is relevant to human OA and that cannot currently be obtained from rodent models or experimentally induced dog models of OA. Ultimately, this Review aims to raise awareness of spontaneous dog OA and to stimulate discussion regarding its exploration under the One Medicine initiative to improve the health and well-being of both species.

The in vitro behaviour of canine osteoblasts derived from different bone types.

BACKGROUND: Our understanding of the biology of osteoblasts is important as they underpin bone remodelling, fracture healing and processes such as osseointegration. Osteoblasts isolated from human humeral samples display distinctive biological activity in vitro, which relates to the samples' bone types (subchondral (S), trabecular (T), cortical (C)). Our aim was to isolate primary osteoblast cultures from different bone types from the proximal femur of a clinical population of dogs presented for total hip replacement and compare the behaviour of the osteoblasts derived from different bone types, to identify a preferred bone type for isolation. RESULTS: No differences were found for osteoblast doubling time (median for S = 2.9, T = 3.1 and C = 2.71 days, respectively; p = 0.33), final cell number (median for S = 54,849, T = 49,733, C = 61,390 cells/cm2; p = 0.34) or basal tissue non-specific alkaline phosphatase (TNAP) activity (median for S = 0.02, T = 0.02, C = 0.03 U/min/mg protein; p = 0.81) between bone types after 6 days of culture in basal media. There were no differences in mineralizing TNAP activity (S = 0.02, T = 0.02, C = 0.03 U/min/mg protein, p = 0.84) or in mineralized area (S = 0.05, T = 0.04, C = 0.04%, p = 0.92) among cells from different bone types. CONCLUSIONS: There is no significant difference in mean doubling time, basal or mineralizing TNAP activity or mineralized area in osteoblasts derived from subchondral, cortical, or trabecular bone types from the canine femoral head. However, there appears to be a high level of inter-animal variability in the studied parameters, which was independent of age, body mass, and sex. Trabecular isolate osteoblasts have the least variation of the bone types studied, and therefore should be considered a preferred source for primary osteoblast cultures. The work here provides baselines for canine osteoblast function, which has utility for future comparative studies.

Feline head trauma: a CT analysis of skull fractures and their management in 75 cats.

OBJECTIVES: The aim of this study was to describe and evaluate the configurations and management of feline skull fractures and concurrent injuries following head trauma. METHODS: Medical records and CT images were reviewed for cats with skull fractures confirmed by CT that were managed conservatively or with surgery. Details of signalment, presentation, skull fracture configuration, management, re-examination, and complications or mortality were recorded and analysed. RESULTS: Seventy-five cats (53 males, 22 females) with a mean age of 4.8 ± 3 years met the inclusion criteria. Eighty-nine percent of cats had fractures in multiple bones of the skull, with the mandible, upper jaw (maxilla, incisive and nasal bones) and craniofacial regions most commonly affected. Temporomandibular joint injury occurred in 56% of cats. Road traffic accidents (RTAs) were the most common cause of skull fractures, occurring in 89% of cats, and caused fractures of multiple regions of the skull. RTAs were also associated with high levels of concurrent injuries, particularly ophthalmic, neurological and thoracic injuries. A more limited distribution of injuries was seen in non-RTA cats. Equal numbers of cats were managed conservatively or surgically (47%). Mortality rate was 8% and complications were reported in 22% of cats. Increasing age at presentation and presence of internal upper jaw fractures were risk factors for development of complications. No risk factors were identified for mortality. CONCLUSIONS AND RELEVANCE: RTAs were the most common cause of feline skull fractures and resulted in fractures in multiple regions of the skull and concurrent injuries occurred frequently. Problems with dental occlusion were uncommon post-treatment. An increased risk of implant loosening and malocclusion was seen with palatine and pterygoid bone fractures and hard palate injuries. This study provides useful additional information regarding feline skull fractures, concurrent injuries and management techniques following head trauma.

Prevalence, duration and risk factors for appendicular osteoarthritis in a UK dog population under primary veterinary care.

Osteoarthritis is the most common joint disease diagnosed in veterinary medicine and poses considerable challenges to canine welfare. This study aimed to investigate prevalence, duration and risk factors of appendicular osteoarthritis in dogs under primary veterinary care in the UK. The VetCompassTM programme collects clinical data on dogs attending UK primary-care veterinary practices. The study included all VetCompassTM dogs under veterinary care during 2013. Candidate osteoarthritis cases were identified using multiple search strategies. A random subset was manually evaluated against a case definition. Of 455,557 study dogs, 16,437 candidate osteoarthritis cases were identified; 6104 (37%) were manually checked and 4196 (69% of sample) were confirmed as cases. Additional data on demography, clinical signs, duration and management were extracted for confirmed cases. Estimated annual period prevalence (accounting for subsampling) of appendicular osteoarthritis was 2.5% (CI95: 2.4-2.5%) equating to around 200,000 UK affected dogs annually. Risk factors associated with osteoarthritis diagnosis included breed (e.g. Labrador, Golden Retriever), being insured, being neutered, of higher bodyweight and being older than eight years. Duration calculation trials suggest osteoarthritis affects 11.4% of affected individuals' lifespan, providing further evidence for substantial impact of osteoarthritis on canine welfare at the individual and population level.