Correlation of Surface Electromyography of the Vastus Lateralis Muscle in Dogs at a Walk with Joint Kinematics and Ground Reaction Forces

Kinematic characteristics of canine hindlimb movement during sit-to-stand and stand-to-sit motions

Sit-to-stand and stand-to-sit motions are basic motions for daily animal life, and these motions are used as therapeutic exercises for dogs with functional impairments. The sit-to-stand motion is divided into several phases for kinesiological assessment in human rehabilitation and physical therapy. However, these motions in dogs have not been characterized in detail. We examined canine hindlimb kinematic characteristics during sit-to-stand/stand-to-sit motions and compared the characteristics with those during walking. In addition, we tried to classify phases of the movements based on kinematic characteristics of the transition of the range of motion of the hindlimb. We used a three-dimensional motion analysis system to evaluate the motions of eight clinically healthy beagles. During the sit-to-stand motion, the total range of motion (ROM) in the hip joint flexion/extension was half of that of during walking, but the total ROM of the hindlimb external/internal rotation relative to the pelvis and flexion/extension of the stifle and the tarsal joints were significantly larger than those of walking, suggesting that sit-to-stand exercise causes movements of hindlimb joints without marked changes in hip joint flexion/extension movement. Both sit-to-stand and stand-to-sit motions could not be divided into multiple phases only by the transition of the range of motion of the hindlimb.

Functional assessment of the gluteus medius, cranial part of the biceps femoris, and vastus lateralis in Beagle dogs based on a novel gait phase classification

In humans, walking analysis based on the gait phase classification has been used for interpretation of functional roles of different movements occurring at individual joints, and it is useful for establishing a rehabilitation plan. However, there have been few reports on canine gait phase classification, and this is one of the reasons for preventing progress in canine rehabilitation. In this study, we determined phases of the canine gait cycle (GC) on the basis of the phase classification for human gait. The canine GC was able to be divided into initial contact (IC) and the following 5 phases: loading response (LR), middle stance (MidSt), pre-swing (PSw), early swing (ESw), and late swing (LSw). Next, the hind limb joint angles of the hip, stifle and tarsal joints and results of surface electromyography of the gluteus medius (GM), cranial part of the biceps femoris (CBF) and vastus lateralis (VL) muscles in relation to the gait phases were analyzed. The activities of three muscles showed similar changes during walking. The muscle activities were high in the LR phase and then declined and reached a minimum in the PSw phase, but they increased and reached a peak in the LSw phase, which was followed by the LR phase. In conclusion, the multiphasic canine GC was developed by modification of the human model, and the GC phase-related changes in the muscle activity and joint angles suggested the functions of GM, CBF and VL muscles in walking.

Surface Electromyography of the Longissimus and Gluteus Medius Muscles in Greyhounds Walking and Trotting on Ground Flat, Up, and Downhill

Simple Summary

In the field of canine physical rehabilitation and sports medicine, knowledge of muscle function in the therapeutic exercises prescribed is needed by physical therapists and veterinary surgeons. The longissimus dorsi and gluteus medius muscles are of great interest due to their role in locomotion related to frequent canine diseases. The muscle activity of these two muscles was studied in five Greyhound dogs performing slow, controlled leash walking and trotting on ground exercises uphill and downhill, commonly prescribed as therapeutic exercises. Results showed that for the same incline, the muscle activity of longissimus muscle was higher at the trot than at the walk. It was also shown that incline and decline affected the muscle activity of the longissimus and gluteus medius muscles of dogs walking or trotting on the ground. Walking and trotting up and downhill added separate therapeutic value to flat motion. The results of the present study might contribute to a better understanding of the function of longissimus and gluteus medius muscles in dogs, this being especially useful for the field of canine rehabilitation.

Abstract

In the field of canine rehabilitation, knowledge of muscle function in the therapeutic exercises prescribed is needed by physical therapists and veterinary surgeons. To gain insight into the function of longissimus dorsi (LD) and gluteus medius (GM) muscles in dogs, five Greyhounds performing leash walking and trotting on the ground flat, up (+7%), and downhill (−7%) were studied by surface electromyography, and the mean and maximum activity was compared. For the same incline, the surface electromyography (sEMG) of LD was higher (p < 0.05) at the trot than at the walk. In LD muscle, trotting uphill showed significantly higher maximum activity than any other exercise. A change of +7% incline or −7% decline affected (increased or decreased, respectively) the mean sEMG of the LD and GM muscles of dogs walking or trotting on the ground. When combined, the influence of gait and incline on electromyographic activity was analyzed, and walking at certain inclines showed no difference with trotting at certain inclines. Walking and trotting up and downhill added separate therapeutic value to flat motion. The results of the present study might contribute to a better understanding of the function of LD and GM muscles in dogs, this being especially useful for the field of canine rehabilitation.

Surface Electromyography of the Vastus Lateralis, Biceps Femoris, and Gluteus Medius in Dogs During Stance, Walking, Trotting, and Selected Therapeutic Exercises

Objective: The objective of the study reported here was to evaluate the muscle activity patterns of the vastus lateralis (VL), biceps femoris (BF), and gluteus medius (GM) during stance, walking, trotting, and selected therapeutic exercises in clinically sound, healthy dogs. Our hypothesis was that the muscle activity during all exercises would differ from muscle activity at the stance. Methods: Surface electromyography of the selected muscles was performed during stance, walking, trotting, elevation of forelimbs on a platform, elevation of forelimbs on a platform with hindlimbs on an inflatable balance device, stepping up onto and over an obstacle, standing on a wobble board, dancing backwards, and wearing a leg weight at the walk and the trot. The maximal and mean muscle amplitude (μV) reflecting activity during several motion cycles were compared among the exercises. Results: Mean EMG amplitude of the BF was significantly higher in all exercises (p < 0.05) in comparison to stance. Mean EMG amplitude of the VL was significantly higher (p < 0.05) during walking, trotting, dancing backwards, stepping up and over an obstacle, and at a trot with a leg weight as compared to stance. Mean EMG amplitude of the GM was significantly higher (p < 0.05) during trotting, at a walk and a trot with a leg weight, standing on a wobble board, stepping up and over an obstacle, and dancing backwards when compared to stance. Of the studied exercises, dancing backwards increased the mean EMG amplitude of the BF and GM to the largest degree. Stepping up and over an obstacle increased the mean EMG amplitude of the VL to the largest degree. Conclusion: Compared to stance, the majority of therapeutic exercises examined increased muscle activity to varying degrees in the BF, VL, and GM. Our results may help clinicians to choose specific exercises to target specific muscles during conditioning, strengthening and rehabilitation.

Neurological functional evaluation based on accurate motions in big animals with traumatic brain injury

An accurate and effective neurological evaluation is indispensable in the treatment and rehabilitation of traumatic brain injury. However, most of the existing evaluation methods in basic research and clinical practice are not objective or intuitive for assessing the neurological function of big animals, and are also difficult to use to qualify the extent of damage and recovery. In the present study, we established a big animal model of traumatic brain injury by impacting the cortical motor region of beagles. At 2 weeks after successful modeling, we detected neurological deficiencies in the animal model using a series of techniques, including three-dimensional motion capture, electromyogram and ground reaction force. These novel technologies may play an increasingly important role in the field of traumatic brain injury diagnosis and rehabilitation in the future. The experimental protocol was approved by the Animal Care and Use Committee of Logistics University of People’s Armed Police Force (approval No. 2017-0006.2).

Kinematic gait analysis of the canine thoracic limb using a six degrees of freedom marker set

Objectives: To determine if the use of a six degrees of freedom marker set would allow new kinematic data of the canine thoracic limbs to be calculated. To identify any significant differences in thoracic limb gait patterns in all planes of motion, between the normal canine population and patients with confirmed medial coronoid disease (MCD).

Method: Two groups of dogs were selected representing the normal Labrador Retriever population (n = 13) and Labrador Retrievers with confirmed MCD (n = 13). Normal dogs had “normal” hip and elbow radiographic scores in line with the International Elbow Working Group and British Veterinary Association guidelines. Medial coronoid disease was confirmed using arthroscopy after kinematic analysis was performed with a six degrees of freedom marker set.

Results: The diseased elbow was nine degrees more extended between 43%-55% of the gait cycle and 16° more supinated prior, early during and after foot strike. The antebrachium was nine degrees more supinated during foot strike and three degrees more abducted during early stance. None of the other parameters were significantly different.

Clinical significance: The use of a six degrees of freedom marker set made it possible for the elbow and antebrachium to be reliably tracked in more than one plane of motion. Significant differences were identified between the normal canine population and those affected by MCD. These data may help elucidate biomechanical factors contributing to aetiopathogenesis of MCD.

Kinetic and kinematic evaluation of compensatory movements of the head, pelvis and thoracolumbar spine associated with asymmetric weight bearing of the pelvic limbs in trotting dogs

Objectives: To determine ground reaction forces, head and pelvis vertical motion (HVM and PVM, respectively), and thoraco-lumbar lateral angular motion (LAM) of the spine using kinematic gait analysis in dogs with mild asymmetric weight-bearing of the pelvic limbs while trotting.

Methods: Twenty-seven hound-type dogs were fitted with reflective markers placed on the sagittal crest of the skull, the ischiatic tuberosity, and thoracolumbar spine of dogs to track motion while trotting. Kinetic and kinematic data were used to characterize asymmetry between the left and right pelvic limbs, and to describe HVM, PVM and thoraco-lumbar LAM. Maximum and minimum position and total motion values were determined for each measured variable.

Results: Dogs with asymmetric weight bearing of the pelvic limbs had greater PVM on the side with a greater peak vertical force (PVF), and greater thoraco-lumbar LAM toward the side with a lower PVF while trotting. No differences in mean HVM were detected, and there were no significant correlations between the magnitude of HVM, PVM and thoraco-lumbar LAM and the degree of asymmetric weight bearing.

Clinical significance: Dogs with subtle asymmetric weight bearing of a pelvic limb had patterns of body motion that may be useful in identifying subtle lameness in dogs; greater PVM on the side with greater weight bearing and greater thoraco-lumbar LAM toward the side with less weight bearing while trotting. Description of these compensatory movements is valuable when evaluating dogs with subtle weight bearing asymmetry in the pelvic limbs and may improve the sensitivity of lameness detection during subjective clinical lameness examination.

The magnitude of muscular activation of four canine forelimb muscles in dogs performing two agility-specific tasks

Background

The purpose of this study was to measure the muscular activation in four forelimb muscles while dogs performed agility tasks (i.e., jumping and A-frame) and to provide insight into potential relationships between level of muscular activation and risk of injury. Muscle activation in eight healthy, client-owned agility dogs was measured using ultrasound-guided fine-wire electromyography of four specific forelimb muscles: Biceps Brachii, Supraspinatus, Infraspinatus, and Triceps Brachii – Long Head, while dogs performed a two jump sequence and while dogs ascended and descended an A-frame obstacle at two different competition heights.

Results

The peak muscle activations during these agility tasks were between 1.7 and 10.6 fold greater than walking. Jumping required higher levels of muscle activation compared to ascending and descending an A-frame, for all muscles of interest. There was no significant difference in muscle activation between the two A-frame heights.

Conclusions

Compared to walking, all of the muscles were activated at high levels during the agility tasks and our findings indicate that jumping is an especially demanding activity for dogs in agility. This information is broadly relevant to understanding the pathophysiology of forelimb injuries related to canine athletic activity.

Pelvic limb kinematics in the dog with and without a stifle orthosis

OBJECTIVE

To report a method of evaluating 3-dimensional joint motion in dogs with a stifle orthosis.

STUDY DESIGN

Experimental.

ANIMALS

Six healthy dogs.

METHODS

Three-dimensional pelvic limb joint motion was recorded with and without a stifle orthosis. Kinematic data were collected from dogs at a walk and trot for the hip, stifle, and tarsus prior to, and after application of, a stifle orthosis. Data were also obtained for the orthosis alone. Comparisons were made between the braced and unbraced limb, and between the braced limb and the orthosis alone. Complete waveforms, kinematic, and temporospatial variables were compared.

RESULTS

Gait waveforms differed between braced and unbraced limbs for all joints and planes of motion (P < .05), as well as between the braced stifles and the orthosis alone at both a walk and trot. However, joint ROM was inconsistently altered. The effect of bracing on stifle ROM was limited to a reduced extension at the end of stance. Adjacent joint ROM was affected by the stifle orthosis. Temporospatial variables were predominantly affected while walking.

CONCLUSIONS

The restrictive motion of the stifle orthosis is not fully translated to the underlying joint, based on the limited differences between the motion of braced and unbraced stifles. This effect varies with plane of motion and phase of the gait cycle, with most changes in stifle motion being detected during the stance phase. The stifle orthosis had an equal or greater effect on the motion of adjacent joints, especially the tarsus.

Surface electromyography in animal biomechanics: A systematic review

The study of muscle activity using surface electromyography (sEMG) is commonly used for investigations of the neuromuscular system in man. Although sEMG has faced methodological challenges, considerable technical advances have been made in the last few decades. Similarly, the field of animal biomechanics, including sEMG, has grown despite being confronted with often complex experimental conditions. In human sEMG research, standardised protocols have been developed, however these are lacking in animal sEMG. Before standards can be proposed in this population group, the existing research in animal sEMG should be collated and evaluated. Therefore the aim of this review is to systematically identify and summarise the literature in animal sEMG focussing on (1) species, breeds, activities and muscles investigated, and (2) electrode placement and normalisation methods used. The databases PubMed, Web of Science, Scopus, and Vetmed Resource were searched systematically for sEMG studies in animals and 38 articles were included in the final review. Data on methodological quality was collected and summarised. The findings from this systematic review indicate the divergence in animal sEMG methodology and as a result, future steps required to develop standardisation in animal sEMG are proposed.

A validated approach for collecting fine-wire electromyographic recordings in four canine shoulder muscles during highly dynamic tasks

This study investigated the feasibility of obtaining ultrasound-guided intramuscular fine-wire electromyographic (fEMG) recordings from four canine shoulder muscles during highly dynamic activities. Four cadaveric canines were utilised to confirm the appropriate anatomical landmarks and the use of real time ultrasound guidance for electrode placement for four shoulder muscles: Biceps Brachii (BB), Supraspinatus (SP), Infraspinatus (IF), and Triceps Brachii – Long Head (TBLH). Electromyographic activity of the left BB, S P, IF, and TBLH was then recorded in two research dogs while walking and trotting to refine the data collection procedures. Finally, the full experimental protocol was piloted with two client-owned, specially-trained agility dogs, confirming the feasibility of collecting fEMG recordings while performing dynamic, highly-specific agility-related tasks and verifying our EMG amplitude normalisation protocol to enable comparisons across muscles and performance tasks. We present specific guidelines regarding the placement of fEMG electrodes and data collection/normalisation procedures to enable investigations of muscle activation during dynamic activities.

Surface Electromyography of the Vastus Lateralis, Biceps Femoris, and Gluteus Medius Muscle in Sound Dogs During Walking and Specific Physiotherapeutic Exercises

OBJECTIVE

To analyze the muscle activity patterns of the vastus lateralis (VL), biceps femoris (BF), and gluteus medius (GM) during walking and specific physiotherapeutic exercises in clinically sound, healthy dogs without lameness.

STUDY DESIGN

Observational study.

ANIMALS

Clinically sound dogs (n = 10).

METHODS

Surface electromyography was performed during walking and exercises (11% incline and decline, walking over cavaletti) within a defined study area. The maximal, minimal, and mean muscle potentials reflecting activity during each motion cycle were compared among the exercises.

RESULTS

During swing phase, maximal VL activity was higher during cavaletti walking compared with walking over ground or incline. Cavaletti walking had an earlier occurrence of the maximum VL activity than did walking over ground or decline. Compared with walking over ground, incline walking had higher minimal GM activity during the 1st half of stance phase and an earlier occurrence of maximal activity during the 2nd half of stance phase. Cavaletti walking had earlier maximal GM activity in swing phase than did walking over ground. Differences between decline and incline walking were seen in all 3 phases of the motion cycle; namely, higher minimal and mean activities occurred during incline walking, and higher maximum activity occurred in the 1st half of stance phase during incline walking. Compared with decline walking, cavaletti walking showed higher minimal and mean activities in the 2nd half of stance phase and higher maximal and mean activities in swing phase.

CONCLUSION

Cavaletti and incline walking exercises increases the VL and GM muscle activity.

Forelimb brachial muscle activation patterns using surface electromyography and their relationship to kinematics in normal dogs walking and trotting

The objective of this study was to determine activity of the elbow flexor and elbow extensor groups of muscles relative to shoulder and elbow joint kinematics in normal walking and trotting dogs using surface electromyography (EMG), and to determine if muscle activity varies with gait or limb. Ten healthy mixed-breed dogs were walked and trotted across embedded force plates in a 6 m walkway while simultaneously recording muscle activation using surface EMG positioned over the biceps brachii (elbow flexor group) and triceps brachii (elbow extensor group); peak shoulder, elbow, and carpal joint angles from motion capture, and ground reaction forces. EMG magnitude, timing, and power spectral density (PSD) were used to analyse muscle activity. The effects of gait type and limb side on EMG measures and joint angles were assessed using an analysis of variance. Results showed that the elbow flexor group was maximally active at end of stance. The elbow extensor group was maximally active at the beginning of stance. Muscle activity occurred earlier in the gait phase (stance or swing) in the trot compared to the walk. The amplitude, frequency at maximum PSD (elbow flexor group only) and the median frequency were larger on the right side than on the left side. The maximum PSD and integrated PSD were larger on the left side than the right side. These data provide a reference for identifying abnormalities associated with orthopaedic, neurological, or rehabilitative changes. Limb asymmetry observed in muscle activation in clinically normal dogs should be further evaluated.

Adaptations in muscle activity to induced, short-term hindlimb lameness in trotting dogs

Muscle tissue has a great intrinsic adaptability to changing functional demands. Triggering more gradual responses such as tissue growth, the immediate responses to altered loading conditions involve changes in the activity. Because the reduction in a limb's function is associated with marked deviations in the gait pattern, understanding the muscular responses in laming animals will provide further insight into their compensatory mechanisms as well as help to improve treatment options to prevent musculoskeletal sequelae in chronic patients. Therefore, this study evaluated the changes in muscle activity in adaptation to a moderate, short-term, weight-bearing hindlimb lameness in two leg and one back muscle using surface electromyography (SEMG). In eight sound adult dogs that trotted on an instrumented treadmill, bilateral, bipolar recordings of the m. triceps brachii, the m. vastus lateralis and the m. longissimus dorsi were obtained before and after lameness was induced. Consistent with the unchanged vertical forces as well as temporal parameters, neither the timing nor the level of activity changed significantly in the m. triceps brachii. In the ipsilateral m. vastus lateralis, peak activity and integrated SEMG area were decreased, while they were significantly increased in the contralateral hindlimb. In both sides, the duration of the muscle activity was significantly longer due to a delayed offset. These observations are in accordance with previously described kinetic and kinematic changes as well as changes in muscle mass. Adaptations in the activity of the m. longissimus dorsi concerned primarily the unilateral activity and are discussed regarding known alterations in trunk and limb motions.

Soft tissue artifact in canine kinematic gait analysis

OBJECTIVE

To investigate, noninvasively, the soft tissue artifact (STA) in canine kinematic gait analysis.

STUDY DESIGN

Experimental study.

ANIMALS

Labrador retrievers (n = 4).

METHODS

Kinematic study: Reflective markers were glued to the skin over bony landmarks, with the distance between 2 markers representing the length of the underlying scapula, humerus, ulna, femur, and crus. The distance between these markers (marker distance [MD]) was measured with infrared cameras while the dogs stood still or walked on a treadmill. Fluoroscopy study: Radiopaque markers were glued on the skin over the spinous process of the L6 vertebra and the stifle to allow fluoroscopic observation of the markers and underlying skeletal segments while the dogs walked on the treadmill. The position of the markers was compared with the position of the underlying skeletal segments during different phases of the step cycle.

RESULTS

Kinematic study: Significant differences were found between MD during standing and walking for all bones investigated. Mean percentage differences in MD ranged from -18% to +6%. Fluoroscopy study: Significant displacements relative to the bony landmarks were found ranging from 0.4 to 1.2 cm.

CONCLUSIONS

Analysis of the motion of skeletal structures with the use of markers attached to the skin showed that the skin moves relative to underlying skeletal structures. When working with a 3-D motion-capture system using skin markers, researchers should be aware that the STA could significantly influence their results.

Inverse dynamics analysis evaluation of tibial tuberosity advancement for cranial cruciate ligament failure in dogs

OBJECTIVE

To evaluate, using inverse dynamic analysis, the biomechanical outcome from tibial tuberosity advancement (TTA) surgery in dogs affected by unilateral cranial cruciate ligament failure (CCLF).

STUDY DESIGN

Retrospective case series.

ANIMALS

Dogs (n = 13) 11-20 months after surgery.

METHODS

Kinematic and force data were collected from 13 dogs 11-20 months after TTA and inverse dynamics analysis of the dogs' pelvic limb mechanical function performed. Angle, moment, and power were calculated for each joint. Total support moment (TSM) was calculated.

RESULTS

Six dogs were affected on the right side (Raff) and 7 on the left (Laff). Peak stifle flexor moment was significantly larger for the right stifle compared with the left in Laff dogs, but similar in Raff dogs. Peak stifle extensor moment was significantly larger for the left stifle compared with the right in Raff dogs, and was also larger for the left stifle compared with the right in Laff dogs. Stifle power in early stance was larger on the left in Raff dogs and significantly larger on the right in Laff dogs. TSM was larger on the right in Raff dogs and significantly larger on the right in Laff dogs.

CONCLUSIONS

Affected limbs had a reduction in power of the stifle flexors. Irrespective of the side of CCLF, TSM was larger on the right side and the stifle extensor moment in late stance was larger on the left, perhaps indicating a mechanical limb dominance effect.

Pelvic limb kinematics and surface electromyography of the vastus lateralis, biceps femoris, and gluteus medius muscle in dogs with hip osteoarthritis

OBJECTIVE

To measure the activity patterns of the vastus lateralis (VL), biceps femoris, and gluteus medius (GM) muscle at a walk in sound dogs and dogs with hip osteoarthritis (OA).

ANIMALS

Dogs (n = 10) with hip OA and 7 clinically sound dogs.

METHODS

Self-reflective markers and a high-speed camera system were used for kinematic measurements and surface electrodes were used for the electromyography (EMG). All measurements were performed on walking dogs. Maximal, minimal, and mean values of the joint angles were evaluated, together with the surface EMG data.

RESULTS

In all muscles investigated, mean activity was significantly decreased during the early swing phase in dogs with hip OA. The VL and GM muscle of the clinically worse pelvic limb had significantly higher activity than the contralateral pelvic limb during early stance.

CONCLUSION

The muscles investigated were significantly affected by hip OA. This finding suggests that there is a more distinct resting phase of the muscles during swing and a higher activity during early stance.