EVJ/EVE Flashcards
Upward fixation of the patella can be a pathologic condition in horses which restricts extension of the distal limb.
i) Describe conservative therapy which can be employed to improve or resolve this condition.
ii) Compare medial patellar desmotomy and medial patellar ligament splitting in terms of outcome and prognosis for surgical correction of this problem with reference to the paper by Anderson and Tnibar (2016).
i) Increasing amounts of exercise, corrective trimming and shoeing, lateral heel wedges, injections of counter irritants into the middle and medial patellar ligaments to increase ligamentous thickness, intramuscular oestrogens to alter ligament laxity and anecdotal claims of acupuncture for improving UFP.
ii) MPD has been surgery of choice when conservative therapy fails. Potential complications include persistent lameness due to osteochondral fragmentation at the distal patella, fibrillation of articular cartilage, osteophytes at the distal patella and enthesophytes in the middle patellar ligament. MPLS is highly effective, minimally invasive and it allows a rapid return
to exercise. In Anderson and Tnibar’s study of 85 horses undergoing MPLS, 97.6% had complete resolution of UFP within 2 weeks of surgery, 2.4% had only unilateral resolution despite bilateral surgery and no complications were reported.
Ref: Anderson and Tnibar, Equine Vet J 2016; 48:312-314.
Describe the technique for navicular bursa injection developed by Daniel et al (2016). What structures may be inadvertently punctured when employing this technique and what factors increase the risk of inadvertent joint/tendon sheath puncture?
A basisesamoid nerve block was performed with 2 ml mepivacaine followed by a standard sterile preparation of the distal limb. An 18 gauge spinal needle was placed through the skin with entry point located: 1) on the proximal or dorsoproximal margin of the collateral cartilages; 2) dorsal to the neurovascular bundle; and 3) dorsal to the dorsoabaxial margin of the DDFT at the level of the collateral cartilage. With a gloved finger placed on the lateral or medial lobe of the DDFT the needle was inserted approximately 1–2 cm through a a palmaroproximolateral-palmarodistomedial oblique trajectory. A lateromedial radiograph was obtained and the angle and direction of the needle adjusted, and the needle was inserted further until it was positioned in a site consistent with the proximal recess of the navicular bursa. 1 ml of a dilute contrast solution (2:1 saline-Omnipaquec [240 mgI/ml]) was injected prior to a final lateromedial radiograph to confirm accurate placement of the needle within the bursa.
Successful navicular bursal injection was achieved in all limbs (n = 71). Relative risk of DIP joint puncture was 19 times higher (95% confidence interval 1.3–285.4, P<0.001) when the DIP joint was distended (9 of 10 limbs) than in normal limbs (0 of 10 limbs). Relative risk of DFTS puncture was 2.7 times higher (95% confidence interval 1.0–7.2, P = 0.06) when the DFTS was distended (8 of 10 limbs) than in normal limbs (3 of 7 limbs).
Ref: Daniel et al, Equine Vet J 2016; 48:159-164.
i) Describe the potential benefits of intrarticular administration of corticosteroids in horses with osteoarthritis.
ii) With reference to the study by de Grauw et al (2016), compare the clinical efficacy of triamcinolone alone and a combination of triamcinolone and hyaluronic acid in horses with clinical joint disease.
i) Reduction in lameness and joint effusion and decreased expression of catabolic and proinflammatory factors in cartilage and/or synovial membranes.
ii) The success rate (improvement of at least 2 grades of lameness) of IA TA 3 weeks after treatment was 87.8%, while that of TA+HA was 64.1% (P = 0.01). Age >13 years was associated with a reduced success rate for the combination treatment (P = 0.004) at 3 weeks. At 3 months, half the horses in each group had returned to their previous level of performance.
The combination of TA with HA was associated with a lower short-term clinical success rate and a similar medium-term outcome compared with IA TA, with only half of the horses performing at their previous level of exercise after 3 months regardless of treatment group allocation.
Ref: de Grauw et al, Equine Vet J 2016; 48:152-158.
Which of the following statements is true regarding the use of tramadol as an analgesic for laminitis (Guedes et al, 2016)?
A. The oral bioavailability of tramadol in horses is widely variable, ranging from 54-89%, resulting in varied analgesic effect in laminitic horses.
B. 5mg/kg tramdadol PO q12h results in decreased heart rate, but not a change in limb off-loading frequency, in horses with chronic laminitis.
C. 10mg/kg tramdadol PO q12h results in decreased limb off-loading frequency, but no change in heart rate, in horses with chronic laminitis.
D. No adverse effects have been reported with oral administration of tramadol in healthy or laminitic horses.
C. 10mg/kg tramdadol PO q12h results in decreased limb off-loading frequency, but no change in heart rate, in horses with chronic laminitis.
Ref: Guedes et al, Equine Vet J 2016; 48:528-531.
Subchondral bone remodelling as a cause of collapse of the articular surface of Thoroughbred racehorses with palmar osteochondral disease was recently investigated by Bani Hassan et al, 2016. Which of the following statements is supported by their findings?
A. An increased extent of articular surface collapse was associated with greater numbers of microfractures in the calcified cartilage and superficial subchondral bone.
B. In the deeper bone there was no association between articular surface collapse and porosity
C. Both porosity and eroded surface of the superficial subchondral bone were higher in training than in resting horses.
D. In the superficial bone porosity was lower with a greater extent of articular surface collapse than in the deeper bone.
A. An increased extent of articular surface collapse was associated with greater numbers of microfractures in the calcified cartilage and superficial subchondral bone.
Ref: Bani Hassan et al, Equine Vet J 2016; 48:228-233.
Which of the following statements is true regarding the incidence of synovial sepsis following rigid arthroscopy (ref: Hawthorn et al, 2016)?
A. The infection rate is 2 per 1000 procedures.
B. The risk of synovial sepsis is higher following arthroscopy than tendon sheath endoscopy.
C. Tarsal sheath tenoscopy carries the highest risk of post surgical sepsis.
D. The risk of synovial sepsis is higher following tendon sheath endoscopy than arthroscopy.
D. The risk of synovial sepsis is higher following tendon sheath endoscopy than arthroscopy.
Ref: Hawthorn et al, Equine Vet J 2016; 48:430-433.
Controversy exists about the specificity of diagnostic analgesia of the digital flexor tendon sheath (DFTS) in horses. If you injected the DFTS with 1ml/50kg mepivacaine would you expect to also achieve therapeutic concentrations in adjacent synovial structures in the hour post-injection which may interfere with the results of your lameness examination? Refer to the work by Jordana et al, 2016 in writing your response.
No. In the referenced study mepivacaine was injected into the DFTS and samples collected from the DFTS, the adjacent metacarpo /metatarsophalangeal (MCP/MTP) joint, proximal interphalangeal joint, distal interphalangeal joint, navicular bursa and contralateral MCP/MTP joint 15 and 60 minutes post injection. In all cases concentrations exceeding the therapeutic threshold were obtained in the DFTS, whereas concentrations of mepivacaine in adjacent synovial structures were very low such that they were clinically irrelevant.
Ref: Jordana et al, Equine Vet J 2016; 48:326-330.
You are presented with a 12 year old Thoroughbred gelding for a prepurchase examination whose intended purpose is eventing. The present owner insists that you only trot the horse out on the narrow grass strip next to her barn as the horse has never been lame for a day in his life. You inform her that you cannot sign a prepurchase certificate under those conditions and instead insist on seeing the horse trotted on a straight line and a circle on grass and concrete because, according to Pfau et al, 2016:
A. A left hindlimb lameness that is not detected on the straight or on the lunge on grass may be evident on the lunge on concrete when the horse is circling to the right.
B. A right forelimb lameness which is apparent on the straight on concrete may not be apparent on the straight or on the lunge on grass and therefore its significance in terms of impact on future performance is questionable.
C. A bilateral forelimb lameness will be more apparent when the horse is lunged in both directions, particularly on concrete.
D. A bilateral hindlimb lameness will be more apparent when the horse is lunged in both directions, particularly on concrete.
C. A bilateral forelimb lameness will be more apparent when the horse is lunged in both directions, particularly on concrete.
Ref: Pfau et al, Equine Vet J, 2016; 48:83-89.
Which of the following Standardbred horses with proximal palmar or plantar osteochondral fragmentation of the first phalynx would be least likely to win a race over 1 mile, according to the research conducted by Carmalt et al?
A. A 4yo gelding with a fragment in the lateral aspect of the joint in the LF 6 months post-arthroscopic removal of the fragment. The gelding had raced 3 times prior to the surgery.
B. A 3yo mare with a fragment in the medial aspect of the joint in the LF 6 months post-arthroscopic removal of the fragment. The mare had never raced prior to the surgery.
C. A 2yo gelding with fragments in the RF, LF and RH prior to to arthroscopic removal of the fragments.
D. A 7yo mare with fragments in both hindlimbs 6 months post-arthroscopic removal of the fragments. The mare had raced prior to the surgery and had also had both joints medicated with glucocorticoids prior to the surgery.
C. A 2yo gelding with fragments in the RF, LF and RH prior to to arthroscopic removal of the fragments.
Ref: Carmalt et al, Equine Vet J 2015; 47:433-437.
Which of the following statements is correct regarding the pathogenesis of bilateral dynamic laryngeal collapse (DLC) associated with poll flexion?
A. There is no neuromuscular component to the pathogenesis of DLC.
B. DLC-affected horses have a greater proportion of T1 fibres within their right cricoarytenoideus muscle.
C. DLC-affected horses have a lesser proportion of T1 fibres within their right cricoarytenoideus muscle.
D. Neurogenic atrophy occurs in the right cricothyroid, cricoarytenoideus lateralis and cricoarytenoideus dorsal muscles of DLC-affected horses.
A. There is no neuromuscular component to the pathogenesis of DLC.
Ref: Fjordbakk et al, Equine Vet J, 2015; 47:603-608.
Describe the normal breathing pattern of horses in the trot, canter and gallop. Describe how the normal respiratory pattern can be altered at a canter and what can cause alterations in this breathing pattern (Fitzharris et al, 2015).
There are poor temporal correlations between breathing and locomotion at trot, however at canter and gallop locomotion and respiration are synchronised (locomotor-respiratory coupling). In canter horses take one breath per stride (1:1 LRC) with occasional big respiratory cycles (BRCs) where a larger breath is taken over 2 strides. A change to 2:1 LRC was reported in 82 horses in a retrospective treadmill study, of which 3 had severe lower respiratory tract disease and 79 had dynamic upper respiratory tract obstruction.
Ref: Fitzharris et al, Equine Vet J, 2015; 47:553-556.
Outline signalment and management factors associated with shivers in horses (Draper et al, 2015).
Shivering is a chronic, often gradually progressive movement disorder that usually begins before 7 years of age and has a higher prevalence in tall male horses. Draper et al’s review confirmed shivering signs often began at <5 years of age and progressed in 74% of cases. Owner-reported additional clinical signs in confirmed cases included muscle twitching (85%), muscle atrophy (44%), reduced strength (33%) and exercise intolerance (33%). Shivering horses were significantly taller (confirmed shivering, mean ∼173 cm; control horses, ∼163 cm) with a higher male:female ratio (confirmed shivering, 3.2:1 vs. control, 1.7:1). No potential triggering factors or effective treatments were reported.
Ref: Draper et al, Equine Vet J 2015; 47:182-187.
Which of the following increases the risk for recurrent colic in horses according to Scantlebury et al, 2015? A. Complete pellet feed diet. B. Pasture-based diet. C. Weaving. D. Circling.
C. Weaving.
Ref: Scantlebury et al, Equine Vet J, 2015; 47:202-206.
A referring veterinarian calls you regarding a 4 year old Thoroughbred gelding that has a long roofing nail stuck right through the central sulcus of the frog. The owners are trying to decide whether to pursue referral for surgery and subsequent medical management or to just try bandaging and antibiotics in the field as they have limited finances and he is not the world’s fastest racehorse. What do you tell the veterinarian (Findley et al, 2014)?
A. Synovial involvement following solar foot penetration has a guarded prognosis for survival to discharge and a poor prognosis for return to pre-injury athletic function. Additionally, penetration of the central sulcus of the frog is associated with euthanasia during hospitalisation, so referral may not be worth their investment if he is of low value.
B. Prognosis for a central frog penetration is better than that for a palmar/plantar frog penetration, with a rate of survival to discharge of 86% and return to pre-injury athletic function of 66%.
C. To remove the nail, thoroughly clean the foot, flush the wound with dilute iodine in sterile saline, bandage the foot and commence systemic broad-spectrum antimicrobial therapy. If the horse deteriorates following this treatment then surgical intervention would be advised.
D. Prognosis for return to function is hopeless in this case, therefore euthanasia is recommended.
A. Synovial involvement following solar foot penetration has a guarded prognosis for survival to discharge and a poor prognosis for return to pre-injury athletic function. Additionally, penetration of the central sulcus of the frog is associated with euthanasia during hospitalisation, so referral may not be worth their investment if he is of low value.
Ref: Findley et al, Equine Vet J, 2014; 46:352-357.
Magnetic blankets have been marketed to improve blood flow, decrease muscle soreness and act as a calming agent in horses. Which of the following was proven by Edner et al, 2015, when comparing magnetic blankets to placebo (cotton not containing magnets) blankets?
A. Blood flow in muscle and skin temperatures were increased and mechanical nociceptive thresholds were decreased in horses wearing magnetic blankets.
B. Skin temperatures, mechanical nociceptive thresholds and behavioural traits did not differ between magnetic and placebo blankets, but blood flow in muscles was improved by magnetic blankets.
C. Blood flow in muscle and skin temperatures were increased and mechanical nociceptive thresholds were decreased in horses wearing placebo blankets.
D. Blood flow in muscle, skin temperatures, mechanical nociceptive thresholds and behavioural traits did not differ between magnetic and placebo blankets.
D. Blood flow in muscle, skin temperatures, mechanical nociceptive thresholds and behavioural traits did not differ between magnetic and placebo blankets.
Ref: Edner et al, Equine Vet J, 2015; 47:302-307.
