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.

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.

Challenges and responsibilities of clinical teachers in the workplace: an ethnographic approach.

This study aimed to explore the complex role of the clinical teacher in the workplace, with a view to identifying effective teaching practices. An ethnographic case-study approach was taken, including participant observations and semi-structured interviews with three participants that were selected from two participating veterinary institutions. The clinical teacher has several responsibilities, such as establishing a rapport with learners and maximizing the use of case-based learning opportunities to provide instruction and support to individual learners in a safe but challenging environment. Associated difficulties include balancing the competing demands of students' learning needs and patients' welfare, as well as maximizing the learning opportunities within available case material. Participants in this study demonstrated a reflective approach, adjusting their teaching approach "in action" and "on action" as appropriate.

Workplace-based assessment instruments in the health sciences.

A historical overview of the development of assessment instruments in the health sciences is presented here, with specific attention paid to workplace-based assessment instruments. Three instruments are reviewed in detail: the mini clinical evaluation exercise (mCEX), direct observation of procedural skills (DOPS), and multi-source feedback (MSF). Features common to these instruments include their authenticity, their use in assessing professional skills, and the opportunities they afford for the provision of feedback. Although almost exclusively used in graduate medical training, they are likely to play an increasingly important role in the assessment of veterinary undergraduate students in preparation for professional practice. However, the time and cost associated with implementing these instruments raises questions about their feasibility. The continued search for the holy grail of assessment instruments and the challenges relating to the need for trained assessors leads us to conclude that ultimately, the competence of health professionals should continue to be measured using several complementary instruments.

Assessment: Cinderella or Sleeping Beauty? Evolution of final examinations at the Royal Veterinary College.

Teachers of veterinary medicine frequently regard assessment as a Cinderella subject. Consciously or unconsciously, they allow assessment systems to become faithful slaves, brought out and dusted off when required, out of sight and out of mind at other times. This often means that assessment is last on the priority list when educational development is considered. Pedagogical literature is full of references to the power of appropriate assessment systems and the role that they can play in shaping and driving the learning environment. "Assessment drives learning" and "Students respect what is inspected" are the headlines associated with such references, and this viewpoint places assessment much more in the role of a Sleeping Beauty, requiring only a simple touch to become a vehicle for modernizing an educational system. This article uses an example of change to a UK veterinary final examination to present the tensions between these contrasting views, and some solutions for them, in an effort to fuel the debate on improving the use of assessment.

Attitudes of veterinary faculty to the assessment of clinical reasoning using extended matching questions.

For assessment purposes, clinical expertise is often divided into three broad components: scientific and clinical knowledge, clinical reasoning, and practical/technical skills. This structure can be used to define the tools used for assessment of clinical students. Knowledge can be assessed through a variety of written formats and skills through various practical assessments, including the objective structured clinical examination (OSCE), but the assessment of clinical reasoning has proved to be far more challenging. A companion paper (Tomlin JL, Pead MJ, May SA. Veterinary students' attitudes toward the assessment of clinical reasoning using extended matching questions. J Vet Med Educ 35:612-621, 2008) reports on the identification and implementation of a valid and reliable method to assess clinical reasoning using clinical-scenario-based extended matching questions (EMQs) in the final examinations at the Royal Veterinary College and looks at students' response to the new examination format. Although EMQs were generally well accepted, many students were concerned about the implied encouragement of pattern recognition, a non-analytical form of clinical reasoning that results from recognition of familiar clinical situations. This paper addresses the attitudes of the teaching faculty to the EMQ format. The students' concerns about promotion of pattern recognition, was also explored in more depth. Overall, faculty perceived EMQs as an appropriate way to test clinical reasoning and as relevant to the experience that students would have gained during their clinical rotations. However, faculty felt that EMQs were difficult to write and that poorly written questions tended to promote pattern recognition. Almost half reiterated the students' concerns that pattern recognition may be an inappropriate reasoning strategy for undergraduates.

Veterinary students' attitudes toward the assessment of clinical reasoning using extended matching questions.

For the purposes of assessment, clinical expertise has been broken down into three broad components: scientific and clinical knowledge, clinical reasoning, and practical or technical skills. This structure can be used to define the tools used for assessment of clinical students. Knowledge can be assessed through a variety of written formats, and skills through various practical assessments, including the objective structured clinical examination. The assessment of clinical reasoning is more of a challenge, and, partly in order to address this challenge, the Royal Veterinary College recently introduced veterinary clinical-scenario-based extended matching questions. A questionnaire was used to collect students' perceptions of the new format. Surprisingly, this questionnaire also delivered important insights into the students' understanding of the process of clinical reasoning itself that could be crucial in future curriculum design. Despite a theory course that introduced students to the nature of expertise and the importance of pattern recognition to experienced clinicians, some final-year students could not recognize this approach as relevant to them and objected to the way in which some of the questions were driving them to think. This may relate to the variety of methods of case management that students observe during their practical experience and the different attitudes of clinicians to the way students work up cases. Overall, the students perceived this question type as an appropriate way to test clinical reasoning and as relevant to the experience they had gained during their clinical rotations, both within the college and in veterinary practices outside it.

Regional load bearing of the feline acetabulum.

OBJECTIVE: To test if the caudal acetabulum of the cat is unloaded at mid-stance as has been asserted. MATERIALS AND METHODS: A kinematic study of five healthy cats was performed to ascertain the mid-stance angle of the hip joint, and the orientation of the pelvis and femur. Femora and pelves from 10 feline cadavers were loaded at physiological load at the mid-stance angle. Impression material placed within the acetabulum was extruded from areas of load bearing. Digital images before and after loading were used to assess whether three areas of the acetabulum, cranial, central and caudal, were fully, partially or non-load bearing. RESULTS: There was a significant difference in load bearing in the three regions (p < 0.001, Kruskal-Wallis test), with a significant difference in load bearing between the cranial and central thirds (p < 0.001) and the cranial and caudal thirds (p < 0.001) but no difference between the central and caudal thirds of the acetabulum (Mann-Whitney-U test). CONCLUSIONS: The load bearing areas of the feline acetabula are the caudal and central thirds. CLINICAL RELEVANCE: The caudal acetabulum of the cat is loaded, therefore the recommendations for simple fractures being treated conservatively needs to be reconsidered.