ORCID Profile
0000-0002-0407-6200
Current Organisation
University of Adelaide
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Publisher: Wiley
Date: 19-05-2021
DOI: 10.1111/EVE.13494
Abstract: Indirect inguinal hernia (IIH) is the most commonly reported acquired hernia in adult horses. Outcomes following surgical intervention comprising of immediate ventral midline laparotomy (IVML) and simultaneous castration are well known. The outcome following reduction of IIH utilising a noninvasive manual reduction (MR) technique in a large number of horses has not been previously reported. To describe a nonsurgical MR technique developed by the authors and to report our long‐term experiences and clinical outcome. Retrospective study. Medical records of 89 stallions presenting with IIH and treated with MR were reviewed. Extensive patient data was collected, with cases grouped based on outcome of the MR procedure and whether or not laparotomy was performed. Data on short‐ and long‐term outcome was obtained. Manual reduction was successful in 80 of 89 (90%) horses. Fifty of 89 (56%) horses were treated with MR only and without exploratory laparotomy. In total 29 of 89 (33%) horses underwent IVML and 10 of 89 (11%) delayed ventral midline laparotomy (DVML). Resections were performed in 6 of 89 (8%) horses. Concurrent small intestinal volvulus was diagnosed in 8 of 89 (9%) horses. Horses undergoing DVML following a successful MR had the highest mortality rates during hospitalisation (4/10, 40%). Short‐term survival was 92% (82/89). Ipsilateral reoccurrence of IIH post‐hospital discharge was recorded in 7 of 47 (15%) horses. Overall long‐term survival with a median of 12 years was 72% (34/47). These include the retrospective nature of data collection, lack of standardised pre‐ and post‐MR clinical assessments and a biased Warmblood population. Manual reduction appears to be a feasible nonsurgical technique to reduce IIH in adult Warmblood horses, with favourable survival rates. In idual case assessment is crucial, as delayed laparotomy may increase mortality rates. Suspicion of concurrent small intestinal volvulus or devitalised small intestine always warrants immediate laparotomy following MR.
Publisher: Wiley
Date: 31-08-2022
DOI: 10.1111/EVJ.13868
Abstract: Horse owners' motivators and barriers for consent to exploratory laparotomy are poorly understood. To (1) determine the proportion of Australian and New Zealand horse owners who would consent to exploratory laparotomy and (2) identify motivators and barriers for consent. Cross‐sectional survey. A questionnaire was developed and distributed online. Descriptive statistics were calculated by tabulating respondents by their answers to whether they would consent to exploratory laparotomy. Univariate and multivariate analyses were used to identify variables associated with consenting to exploratory laparotomy. Two thousand two hundred horse owners participated with a 68.3% survey completion rate. Most were female (95.6%), and 18.7% stated they would consent to exploratory laparotomy, 55.2% would consider exploratory laparotomy and 26.1% would not consent to exploratory laparotomy being performed on their horse. Geographical location, intended use of the horse and perceptions regarding the cost and prognosis of exploratory laparotomy, as well as the previous experience of respondents significantly impacted the decision. Self‐reported level of financial comfort, gender of respondents, number of horses owned and pre‐existing relationship with nearest equine referral clinic did not impact the decision. Top motivators for exploratory laparotomy were high probability of survival, trust in hospital, emotional value of horse and the alternative being euthanasia. Top barriers for exploratory laparotomy were financial cost, uncertain outcome, welfare concern and age of the horse. Self‐selection bias and acquiescence in responses. Most respondents indicated that they would consider or consent to exploratory laparotomy. Several factors for owners to decide for exploratory laparotomy could be identified. Improved owner education regarding the positively reported survival rates for exploratory laparotomy would be beneficial.
Publisher: MDPI AG
Date: 12-05-2023
DOI: 10.3390/ANI13101623
Abstract: Equine gastric ulcer syndrome (EGUS) is a highly prevalent and presumptively painful condition, although the amount of pain horses might experience is currently unknown. The aims of this study were to determine if the Horse Grimace Scale (HGS) could identify pain behaviours in horses with and without EGUS and if severity would be positively associated with the HGS score. Horse grimace scale scores were assessed blindly using facial photographs by seven observers and involved evaluation of 6 facial action units as 0 (not present), 1 (moderately present) and 2 (obviously present). Lameness examination, serum amyloid A (SAA) measurement and gastroscopy evaluation were performed on all horses. Horses (n = 61) were ided into two and three groups based on the presence (yes, no) and severity (none, mild, moderate-severe) of EGUS, respectively. Presence of lameness and elevated SAA (≥50 µg/mL) were used as exclusion criteria. Inter-observer reliability was analyzed by intra-class correlation coefficients (ICC). HGS scores between groups were compared using Welch’s and Brown Forsythe tests (p 0.05). Overall, HGS ICC was “excellent” (0.75). No significant differences (p = 0.566) were observed in HGS scores between horses with and without gastric lesions (mean, 95% CI 3.36, 2.76–3.95 and 3, 1.79–4.20, respectively). HGS was not influenced by the presence or severity of EGUS in this current study. Further studies investigating the use of different pain scales in horses with EGUS are needed.
Publisher: Wiley
Date: 09-10-2021
DOI: 10.1111/JVIM.16285
Abstract: A 7‐year‐old neutered male alpaca ( Vicugna pacos ) was presented for evaluation of a 3‐year history of large, bilateral, firm ventral cervical masses causing esophageal and tracheal impingement. Ultrasound examination, radiographic evaluation, histopathological findings, and magnetic resonance imaging confirmed the masses to be bilateral thyroid adenomas. Conservative medical treatment by unilateral chemical ablation, using 10% formalin by aspiration technique, was performed on the left mass. Chemical ablation proved to be effective in decreasing the size of the mass, with no apparent adverse effects. To our knowledge, this case is the first known report of bilateral thyroid adenomas in an alpaca, a condition previously described in humans, horses, dogs, and cats.
Publisher: Wiley
Date: 03-03-2020
DOI: 10.1111/EVE.13245
Abstract: A 2‐year‐old French Warmblood stallion was presented for lameness investigation. The diagnostic procedures identified the reason for lameness as being a subchondral cystic‐like lesion (SCL) in the glenoid cavity of the scapula. The horse was surgically treated with a translesional 4.5 mm cortical bone screw inserted through the SCL under radiographic guidance. Sixty days after surgery, the horse was sound and the SCL showed significant radiographic signs of healing. Radiographs obtained 180 days after surgery showed further radiographic healing, with the SCL presenting a radiodensity similar to the surrounding bone. At 4 years post‐operative follow‐up, the horse is sound and competing successfully as a 6‐year‐old in Concours de Saut International (CSI) competitions.
Publisher: Wiley
Date: 11-2011
Publisher: Wiley
Date: 21-11-2018
DOI: 10.1111/EVE.13022
Publisher: Wiley
Date: 21-12-2021
DOI: 10.1111/EVE.13604
Abstract: Intussusception is an infrequent cause of equine colic, most commonly encountered in young horses. This condition occurs due to abnormalities of motility and frequently includes the caecum. The purpose of this study was to review the cases of equine small intestinal (SI) intussusception excluding those with caecal involvement. Case series, analytical retrospective study. Medical records of all horses that had SI intussusception, not involving the caecum, from three equine clinics between 2009 and 2020 were reviewed. Information obtained included: clinical parameters, surgical or necropsy findings, complications and outcome. The Mann‐Whitney U test was used to compare the outcome and complications with various parameters. Fisher’s exact test was used to compare short‐term survival with categorical variables. Significance was set at p ≤ 0.05. Twenty‐six horses met the inclusion criteria. Median age of horses was 9 months (interquartile range 2.8 months–6.5 years). Relevant history included diarrhoea and general anaesthesia. Twenty‐two out of 26 horses were diagnosed during surgery and 4 at necropsy. During surgery, 5 horses were subjected to euthanasia, 9 underwent manual reduction and 8 underwent resection and anastomosis. The postoperative complication rate was high at 47% and included ileus, diarrhoea and colic. The prognosis decreased when the involved segment was longer ( p = 0.032), lactate levels were higher ( p = 0.024) and reflux was present before admission ( p = 0.024). Of all horses, 53% survived to discharge and 92% of these survived for year post‐operatively (one case was lost to follow‐up). The retrospective nature of the study and the low number of cases included. Small intestinal intussusception was diagnosed in horses of a variety of breeds and ages. Alterations of motility can predispose to intussusception, not only due to hypermotility (diarrhoea), but also due to hypomotility (anaesthesia). Prognosis for hospital discharge was fair however, following hospital discharge, the long‐term survival rate is high and complications are rare.
Publisher: Wiley
Date: 07-2004
Publisher: Wiley
Date: 05-2010
Publisher: Wiley
Date: 05-01-2010
DOI: 10.2746/042516403776148183
Abstract: Inflammation of the digital flexor tendon sheaths is a chronic and nebulous condition often unresponsive to medical and surgical treatment. To evaluate the incidence of longitudinal tears (LT) as the underlying cause of chronic tenosynovitis and annular ligament constriction syndrome (ALCS) in warmblood horses. The records of 25 horses with chronic tenosynovitis and ALCS in which tenoscopical inspection of the digital flexor tendon sheath (DFTS) was performed between 1999-2000 were reviewed. Of 25 horses, 17 were diagnosed with an LT in the deep digital flexor tendon (DDFT). All horses had a history of distension of the DFTS and/or signs of an ALCS. All cases presented typical signs of a chronic inflamed DFTS on ultrasonography and 11 horses showed ultrasonographic changes (echogenic material or an irregular outlining) at the lateral or medial border of the DDFT. The diagnosis of LTs of the DDFT was established in all cases by tenoscopy. Surgical treatment consisted of removal of the torn collagen fibrils using a mechanical resector and decompressing the fetlock canal by a transection of the palmar annular ligament (PAL) using a hook knife under tenoscopic control. Ten horses became sound and resumed their previous level of work, 3 horses remained lame, 4 horses returned to previous level of work but needed intrasynovial treatment of the DFTS and reduced competition frequency to remain sound. Horses presented with chronic inflamed DFTS and/or ALCS might suffer from LTs in the DDFT however, the diagnosis cannot be established with absolute certainty using only ultrasonography. Longitudinal tears should be suspected if ultrasonographic changes are present lateral or medial to the border of the DDFT but tenoscopical examination of the tendon sheath is essential to establish an accurate diagnosis and an effective treatment. The presence of these LTs might explain why some cases of chronic tenosynovitis of the digital flexor tendon sheath and/or ALCS do not respond on surgical transection of the PAL alone without tenoscopy.
Publisher: Wiley
Date: 08-06-2011
DOI: 10.1111/J.2042-3306.2010.00341.X
Abstract: Longitudinal tears (LTs) of the digital flexor tendons are an important cause of chronic tenosynovitis of the digital flexor tendon sheath (DFTS). The origin of those marginal tears is not yet fully understood. The long-term outcome after medical and surgical treatment is guarded. To determine the prevalence of LTs of the digital flexor tendons in a large population of horses undergoing diagnostic tenoscopy of the DFTS and to assess the outcome of surgical treatment and the factors influencing the outcome. Medical records of 130 horses with chronic tenosynovitis of the DFTS that had tenoscopic surgery between 1999 and 2009 were evaluated. One hundred and thirty-five DFTSs were examined. LTs were diagnosed in 104 DFTSs in 101 horses and long-term follow-up was obtained. Seventy-eight percent of the horses with a nonseptic tenosynovitis of the DFTS had a LT. Preoperative ultrasonographic examination diagnosed tears in 76% of the cases. In showjumpers forelimbs were more frequently affected than hindlimbs (88 vs. 12%), with the right front having a higher incidence of injury than the left front (76 vs. 24%). Seventy-nine percent of the tears involved the deep digital flexor tendon (DDFT) and 87% were located on the lateral tendon border. Thirty-seven horses (38%) returned to an equal or higher level of work. The use of a radiofrequency probe (coblation) was associated with a lower level of performance and decreased the cosmetic end result. Persistence of marked post operative distension of the DFTS carried a poor prognosis for return to previous level of work. A guarded prognosis for future soundness should be given to horses presented for treatment of LTs of the digital flexor tendons. The use of coblation wands had a negative effect on the final outcome.
No related grants have been discovered for Olivier Simon.