Towards standardisation of surface electromyography measurements in the horse: Bipolar electrode location

The use of surface electromyography in the field of animal locomotion has increased considerably over the past decade. However, no consensus exists on the methodology for data collection in horses. This study aimed to start the development of recommendations for bipolar electrode locations to collect surface electromyographic data from horses during dynamic tasks. Data were collected from 21 superficial muscles of three horses during trot on a treadmill using linear electrode arrays. The data were assessed both quantitatively (signal-to-noise ratio (SNR) and coefficient of variation (CoV)) and qualitatively (presence of crosstalk and activation patterns) to compare and select electrode locations for each muscle. For most muscles and horses, the highest SNR values were detected near or cranial/proximal to the central region of the muscle. Concerning the CoV, there were larger differences between muscles and horses than within muscles. Qualitatively, crosstalk was suspected to be present in the signals of twelve muscles but not in all locations in the arrays. With this study, a first attempt is made to develop recommendations for bipolar electrode locations for muscle activity measurements during dynamic contractions in horses. The results may help to improve the reliability and reproducibility of study results in equine biomechanics

L imagerie médicale du carpe du cheval (images de référence et applications au dépistage de certaines affections sporadiques)

Le but de cette thèse est d illustrer l importance de l imagerie médicale dans le diagnostic des affections du carpe chez le cheval. Tout d abord, l anatomie du carpe est décrite en détail. Ensuite, les principes physiques et les avantages de la radiographie, de l échographie, de l arthroscopie, de l IRM et de la tomodensitométrie axiale du carpe sont expliqués et discutés. Des images de références sont expliquées en détail. Enfin, nous avons utilisé certaines pathologies sporadiques du carpe pour illustrer la puissance diagnostique de l imagerie médicale. Cette thèse repose sur une large revue bibliographique. Le pathologies étudiées sont les fractures de l os accessoire du carpe, les fragments ostéochondraux de la face palmaire, les fractures para-sagittales de l os carpal III, les desmites de la bride radiale, desmites des ligaments collatéraux et les desmites des ligaments intercarpiens palmaires.TOULOUSE-EN Vétérinaire (315552301) / SudocSudocFranceF

CT measures of osseous cervicothoracic intervertebral foramina are repeatable and associated with CT measures of adjacent articular processes in horses

Narrowing of the equine cervicothoracic intervertebral foramina (IF) has the potential to cause forelimb lameness and/or neck pain although limited information is available on CT of the IF. The aims of this retrospective, analytical study were to describe a protocol for quantifying CT cervicothoracic IF size; evaluate the repeatability of IF size measures; test associations between IF size and adjacent articular process (AP) size, ventral extent, and anatomic location; and determine the proportion of IF with narrowing. Computed tomographic images were acquired in 20 Warmblood horses that presented with forelimb lameness and/or neck pain. All IF between C5 and T2 (n = 160) were evaluated. IF cross-sectional area (CSA), APCSA, and AP ventral extent were measured. The repeatability of IFCSA measurement was calculated. Possible associations between IFCSA and: APCSA, ventral extent, side, or location were assessed. IF narrowing was defined as more than 50% of reduction in IF height when compared with its widest part(s). The repeatability of IFCSA measurement was excellent. There was a significant association between IFCSA and: APCSA (P R-2 = 0.859; slope = -0.106), ventral extent (P = 0.022; R-2 = 0.161; slope = -0.0617), and location (P < 0.001; higher values between C7 and T2). The association between IFCSA and ventral extent was small. Narrowing was identified in 61 (38.1%) IF. Maximum degree of narrowing was most common at the cranial (26.3%) and middle (68.8%) third of the IF. Narrowing was not identified at T1-T2. In conclusion, CT cervicothoracic IF size can be measured with excellent repeatability, and associations were found between IF size and: AP size, ventral extent, and location

Computed tomographic features and surgical treatment of equine mandibular aneurysmal bone cysts with β-tricalcium phosphate in a multicenter case series

OBJECTIVE To describe clinical and imaging features and surgical treatment of equine mandibular aneurysmal bone cysts (ABCs) with β-tricalcium phosphate (TCP). ANIMALS 3 horses (cases 1, 2, and 3) and 1 pony (case 4) with histologically confirmed ABC. CLINICAL PRESENTATION All cases had mandibular swelling with intact adjacent skin. Cases 1 to 3 had a body condition score of 3/5 and case 4 had 2/5 and showed quidding during mastication and, at oral examination, large interdental spaces and loose elements adjacent to the swelling. Radiography or CT was performed in all cases. In cases 1, 3, and 4, an expansile septate cystic space-occupying lesion with mass effect on the adjacent cortices and teeth was seen without compact bone destruction. Case 2 showed a heterogeneous osteolytic mass with multifocal cortical lysis and interruption. Case 4 had severe dental abnormalities of deciduous and precursors of permanent teeth. ABCs were surgically treated and filled with only TCP (case 3) or in combination with autologous bone marrow (cases 1, 2, and 4). RESULTS Cases 1 through 3 showed an uneventful reduction in ABC size with increased opacity/attenuation. In case 4, a surgical site infection occurred. After removal of TCP remnants, the ABC healed satisfactorily, but remaining dental abnormalities necessitated dietary adjustments to maintain an acceptable body condition score. CLINICAL RELEVANCE Treatment of ABCs with TCP had a favorable outcome and good long-term prognosis. In young specimens, the expansile effect on the development and eruption of neighboring teeth can influence and determine final functionality of the diseased dental quadrant

Computed tomographic myelography for assessment of the cervical spinal cord in ataxic warmblood horses : 26 cases (2015-2017)

OBJECTIVE : To quantify the degree of dural compression and assess the association between site and direction of compression and articular process (AP) size and degree of dural compression with CT myelography. ANIMALS : 26 client-oriented horses with ataxia. PROCEDURES : Spinal cord-to-dura and AP-to-cross-sectional area of the C6 body ratios (APBRs) were calculated for each noncompressive site and site that had > 50% compression of the subarachnoid space. Site of maximum compression had the largest spinal cord-to-dura ratio. Fisher exact test and linear regression analyses were used to assess the association between site and direction of compression and mean or maximum APBR and spinal cord-to-dura ratio, respectively. RESULTS : Mean +/- SD spinal cord-to-dura ratio was 0.31 +/- 0.044 (range, 0.20 to 0.41) for noncompressive sites and 0.44 +/- 0.078 (0.29 to 0.60) for sites of maximum compression. Sites of maximum compression were intervertebral and extra-dural, most frequently at C6 through 7 (n = 10), followed by C3 through 4 (6). Thirteen horses had dorsolateral and lateral compression at the AP joints, secondary to AP (n = 7) or soft tissue proliferation (6). Site significantly affected direction of compression, and directions of compression from occiput through C4 were primarily ventral and lateral, whereas from C6 through T1 were primarily dorsal and dorsolateral. No linear relationship was identified between mean or maximum APBR and spinal cord-to-dura ratio. CONCLUSIONS AND CLINICAL RELEVANCE : CT myelography may be useful for examination of horses with suspected cervical compressive myelopathy. Degree of compression can be assessed quantitatively, and site of compression significantly affected direction of compression

Electrode positioning in the horse: towards standardisation of surface EMG measurements

Surface electromyography (sEMG) is a well-established method in human gait analysis, and its application has extended towards the equine field in the past decades. However, methodological consensus regarding electrode positioning is lacking, resulting in different user methodologies, hampering study comparison and repeatability. This study investigated the standardisation of bipolar electrode positioning to measure muscle activity in horses during dynamic contractions. Ultrasound scans were made of three muscles (Triceps Brachii caput longum (TB), Longissimus Dorsi (LD), and Semitendinosus (ST)) of six horses to determine the muscle borders and fibre direction. Linear arrays of approximately ten electrodes (4 mm diameter, 20 mm inter-electrode distance) were placed on the clipped and cleaned skin, parallel to the muscle fibre direction. The middle of the array was always placed at 50% between two anatomical landmarks chosen near (one of ) the origins and insertions of the respective muscle. Data were collected (SAGA® TMSi, 4,000 Hz) for one minute at trot on a treadmill. The root mean square (RMS) values, innervation zone (IZ) location and presence of crosstalk were determined to evaluate electrode positions. The optimal positions were at 40-49 and 32-45% between the used anatomical landmarks for TB and ST respectively. Electrodes positioned within the thoracic region of the LD recorded higher, i.e. better, RMS values compared to electrodes in the lumbar region, though results were similar regarding IZ location and presence of crosstalk. The proposed positions may serve as a standardised reference for bipolar electrode placement to measure sEMG in horses during dynamic contractions.Effect of body position on a 3-dimensional scanning assessment of muscle massA. Borer-Matsui1, G.C. Donnelly2 and S. Valberg11Michigan State University, Large Animal Clinical Sciences, 736 Wilson Rd, 48824, East Lansing MI, USA, 2University of California, Davis, Department of Population Health and Reproduction, One Shields Drive, 95616, Davis CA, USA; [email protected] performance relies on well-developed musculature which has been difficult to accurately measure. We recently devised a 3-dimensional photonic scan to capture body volume (V) as a proxy for muscle mass validated in horses with 4 hooves square, a difficult stance to achieve. The purpose of this study was to determine the effect of modest differences in body position on measurement of body V. Anatomic markers were placed on 8 horses positioned with; 4 hooves square; neck turned ⌁25°; head raised mean 17 cm; one hind hoof (HH) anterior offset ⌁15 cm; a front and opposite HH ⌁15 cm offset (n=7); one HH resting. A handheld Occipital Structure Sensor scanner connected to an iPad and Skanect and Materialise 3-Matic programs were used to capture V in specific body sectors delineated by anatomic markers. Volume of back and hindquarter sectors standing square were compared to various positions using ANOVA (

Computed tomographic examination of the articular process joints of the cervical spine in warmblood horses : 86 cases (2015-2017)

OBJECTIVE To describe articular process joints (APJs) of the cervical spine in horses on the basis of CT and to determine whether abnormalities were associated with clinical signs. ANIMALS 86 client-owned warmblood horses. PROCEDURES Horses that underwent CT of the cervical spine between January 2015 and January 2017 were eligible for study inclusion. Medical records were reviewed for age, body weight, breed, sex, history, clinical signs, and CT findings. Horses were divided into 3 case groups and I control group on the basis of clinical signs. RESULTS 70 warmblood horses were cases, and 16 were controls. Abnormalities were more frequent from CS through TI and were severe in only horses from the case group. Narrowing of the intervertebral foramen was common in horses in the case group (85.7%), often owing to enlarged, misshaped articular processes, followed by degenerative changes, periarticular osteolysis, cyst-like lesions, and fragmentation. High articular process-to-vertebral body (C6) ratio (APBR) and high-grade narrowing of the intervertebral foramen and periarticular osteolysis were noted for horses with forelimb lameness or signs of cervical pain or stiffness. No association was identified between APBR and age or sex. An APBR > 1.5 was found in only horses in the case group, and 32.3% of APJs with APBRs > 1.5 did not have any degenerative changes and periarticular osteolysis. CONCLUSIONS AND CLINICAL RELEVANCE CT was useful to identify abnormalities of the APJs of the cervical spine. An association existed between CT findings and clinical signs. The APJs can be enlarged without concurrent degenerative changes

Electrode positioning in the horse: towards standardisation of surface EMG measurements

Surface electromyography (sEMG) is a well-established method in human gait analysis, and its application has extended towards the equine field in the past decades. However, methodological consensus regarding electrode positioning is lacking, resulting in different user methodologies, hampering study comparison and repeatability. This study investigated the standardisation of bipolar electrode positioning to measure muscle activity in horses during dynamic contractions. Ultrasound scans were made of three muscles (Triceps Brachii caput longum (TB), Longissimus Dorsi (LD), and Semitendinosus (ST)) of six horses to determine the muscle borders and fibre direction. Linear arrays of approximately ten electrodes (4 mm diameter, 20 mm inter-electrode distance) were placed on the clipped and cleaned skin, parallel to the muscle fibre direction. The middle of the array was always placed at 50% between two anatomical landmarks chosen near (one of ) the origins and insertions of the respective muscle. Data were collected (SAGA® TMSi, 4,000 Hz) for one minute at trot on a treadmill. The root mean square (RMS) values, innervation zone (IZ) location and presence of crosstalk were determined to evaluate electrode positions. The optimal positions were at 40-49 and 32-45% between the used anatomical landmarks for TB and ST respectively. Electrodes positioned within the thoracic region of the LD recorded higher, i.e. better, RMS values compared to electrodes in the lumbar region, though results were similar regarding IZ location and presence of crosstalk. The proposed positions may serve as a standardised reference for bipolar electrode placement to measure sEMG in horses during dynamic contractions.Effect of body position on a 3-dimensional scanning assessment of muscle massA. Borer-Matsui1, G.C. Donnelly2 and S. Valberg11Michigan State University, Large Animal Clinical Sciences, 736 Wilson Rd, 48824, East Lansing MI, USA, 2University of California, Davis, Department of Population Health and Reproduction, One Shields Drive, 95616, Davis CA, USA; [email protected] performance relies on well-developed musculature which has been difficult to accurately measure. We recently devised a 3-dimensional photonic scan to capture body volume (V) as a proxy for muscle mass validated in horses with 4 hooves square, a difficult stance to achieve. The purpose of this study was to determine the effect of modest differences in body position on measurement of body V. Anatomic markers were placed on 8 horses positioned with; 4 hooves square; neck turned ⌁25°; head raised mean 17 cm; one hind hoof (HH) anterior offset ⌁15 cm; a front and opposite HH ⌁15 cm offset (n=7); one HH resting. A handheld Occipital Structure Sensor scanner connected to an iPad and Skanect and Materialise 3-Matic programs were used to capture V in specific body sectors delineated by anatomic markers. Volume of back and hindquarter sectors standing square were compared to various positions using ANOVA (