Shoulder Lameness in Dogs: Preliminary Investigation on Ultrasonography, Signalment and Hemato-Biochemical Findings Correlation

Animal model for tendinopathy

Background

Tendinopathy is a common motor system disease that leads to pain and reduced function. Despite its prevalence, our mechanistic understanding is incomplete, leading to limited efficacy of treatment options. Animal models contribute significantly to our understanding of tendinopathy and some therapeutic options. However, the inadequacies of animal models are also evident, largely due to differences in anatomical structure and the complexity of human tendinopathy. Different animal models reproduce different aspects of human tendinopathy and are therefore suitable for different scenarios. This review aims to summarize the existing animal models of tendinopathy and to determine the situations in which each model is appropriate for use, including exploring disease mechanisms and evaluating therapeutic effects.

Methods

We reviewed relevant literature in the PubMed database from January 2000 to December 2022 using the specific terms ((tendinopathy) OR (tendinitis)) AND (model) AND ((mice) OR (rat) OR (rabbit) OR (lapin) OR (dog) OR (canine) OR (sheep) OR (goat) OR (horse) OR (equine) OR (pig) OR (swine) OR (primate)). This review summarized different methods for establishing animal models of tendinopathy and classified them according to the pathogenesis they simulate. We then discussed the advantages and disadvantages of each model, and based on this, identified the situations in which each model was suitable for application.

Results

For studies that aim to study the pathophysiology of tendinopathy, naturally occurring models, treadmill models, subacromial impingement models and metabolic models are ideal. They are closest to the natural process of tendinopathy in humans. For studies that aim to evaluate the efficacy of possible treatments, the selection should be made according to the pathogenesis simulated by the modeling method. Existing tendinopathy models can be classified into six types according to the pathogenesis they simulate: extracellular matrix synthesis-decomposition imbalance, inflammation, oxidative stress, metabolic disorder, traumatism and mechanical load.

Conclusions

The critical factor affecting the translational value of research results is whether the selected model is matched with the research purpose. There is no single optimal model for inducing tendinopathy, and researchers must select the model that is most appropriate for the study they are conducting.

The translational potential of this article

The critical factor affecting the translational value of research results is whether the animal model used is compatible with the research purpose. This paper provides a rationale and practical guide for the establishment and selection of animal models of tendinopathy, which is helpful to improve the clinical transformation ability of existing models and develop new models.

Use of acoustic myography to evaluate forelimb muscle function in retriever dogs carrying different mouth weights

OBJECTIVES

To evaluate the effect of mouth weight on gait and relative function of forelimb muscles in retriever hunting dogs as a possible explanation for biceps tendinopathy.

METHODS

Ten sound retriever dogs underwent acoustic myography, measuring efficiency (E-score), spatial summation (S-score), and temporal summation (T-score) during walk and trot on a pressure-sensitive walkway while carrying a 0 lb (0 kg), 1 lb (0.45 kg), and 3.2 lb (1.45 kg) mouth weight. Gait data included total pressure index (TPI), step length, and stance time. Statistics included a mixed effects model significant at p < 0.05.

RESULTS

Forelimb TPI increased with increasing weight. There was no significant change in individual muscle parameters in response to weight. Significance was found in between-muscle comparisons. For walk, T-score was significantly lower in triceps vs. brachiocephalicus with 1 lb, not with 3.2 lb., S-score was significantly lower in the biceps at 0, 1 lb, and triceps at 0 lb. when compared to brachiocephalicus, E-score was significantly lower in deltoideus vs. brachiocephalicus at trot with l and 3.2 lb. There was an overall significant effect of muscle on T-score at trot, but no individual muscle comparison was significant.

CONCLUSION

Forelimb load increases with mouth weight. Deltoideus had a longer contraction time in response to increasing weight at trot when compared to brachiocephalicus. The biceps muscle did not show increased work in response to increasing weight.

CLINICAL RELEVANCE

The underlying etiology of biceps tendinopathies in retriever dogs remains uncertain but is not due to increasing weight.

Case study: Treating infraspinatus and supraspinatus trigger points and supraspinatus tendinopathy utilizing piezoelectric shockwave

Two individual case studies demonstrate piezoelectric shockwave treatment for the resolution of a supraspinatus tendinopathy and supraspinatus and infraspinatus myofascial trigger points (MTPs) via musculoskeletal ultrasound. This is the first documentation of improvement of both tendon and muscle fiber patterns in canine patients treated with piezoelectric shockwave. These cases validate the use of piezoelectric shockwave during the rehabilitation of common canine shoulder injuries.

Military Working Dogs Operating in Afghanistan Theater: Comparison between Pre- and Post-Mission Blood Analyses to Monitor Physical Fitness and Training

Simple Summary

In modern conflicts, one of the greatest risks for military personnel is represented by explosive devices. For this reason, specifically trained dogs able to detect explosives have been more and more intensively used in humanitarian military operations. However, at present, literature regarding working problems reported by these animals is very limited. The a of this study was to evaluate the health status of military dogs participating in humanitarian missions to Afghanistan, comparing their pre- and post-mission blood work. Dogs were first considered together as a group and then divided in groups by age, sex, breed and mission length. The results of the study show that there are no particular differences between their blood work before and after the missions. This indicates that the recorded dogs were physically well prepared to face their tasks.

Abstract

The intergovernmental organization known as the United Nations (UN) was born “to maintain international peace and security” through different operations and tasks, including “mine action” and “explosive detection”. Explosives are the most frequent cause of injuries in military personnel and an enormous danger for civilians. The role of explosive detection dogs (EDDs) and mine detection dogs has gained great consideration over time, leading to their intense use in military operations. Literature regarding working injuries reported by EDDs during missions is limited. The aim of the present study is to investigate the hematological changes that occurred between pre- and post-mission blood analyses in military working dogs deployed to Afghanistan in order to evaluate signs of health problems or physical adjustments. Examining the clinical records, only three dogs reported a medical issue, one with gastric dilatation-volvulus (GDV), and two with lameness episodes. Lack of health issues occurring during the missions was reflected by the absence of significant differences between pre- and post-mission blood analyses. Blood results were also examined by dividing the EDDs into groups considering age at departure, sex, breed and mission length. A few categories demonstrated significant changes in some parameters; however, the mean values were always included in the ranges of normality, indicating that their physical fitness and training were adequate for the required tasks.

Orthopedic and ultrasonographic examination findings in 128 shoulders of 64 ultra-endurance Alaskan sled dogs

OBJECTIVE

To determine the location and periarticular shoulder-muscle-abnormalities detected via orthopedic examinations and ultrasonography in ultra-endurance Alaskan sled-dogs, returned from an ultra-endurance sled-dog-race prior to finishing it.

STUDY DESIGN

Prospective clinical study.

SAMPLE POPULATION

Sixty-four dogs (128 shoulders).

METHODS

Dogs were classified based on clinical evidence of shoulder pain (SP versus control). Orthopedic examination findings, shoulder-abduction-angles (SAA; before- and during-anesthesia), and ultrasonographic findings were recorded. Relationships between orthopedic and ultrasonographic abnormalities were compared.

RESULTS

Pain was elicited on 55/128 shoulders; 73 shoulders were pain-free. The most common painful structures included the biceps-tendon (BT; 30%), triceps-muscle (28%), and infraspinatus-muscle (25%). SAA ranged between 25° and 75° among groups, including pain-free shoulders in dogs without lameness. SAA was greater when dogs were anesthetized (46.3° ± 14.0° vs. 47.8° ± 12.0°; p = .03), especially in SP (mean increase of 3.49° ± 8.85°) compared to control (0.03° ± 7.71°, p = .009). Overall, 103 ultrasonographic abnormalities were detected (SP: 44; control: 59). The most common ultrasonographic abnormality was fluid surrounding the biceps tendon, similarly distributed between groups (SP: 39/44; control: 57/59). Most chronic ultrasonographic abnormalities affected the BT (15/103 abnormalities). No associations were detected between ultrasonographic abnormalities and clinical findings.

CONCLUSION

Shoulder abduction varied greatly and reached up to 75° in normal joints. Ultrasonographic shoulder-muscle abnormalities were common but did not seem associated with clinical findings.

CLINICAL SIGNIFICANCE

Interpretation of shoulder abduction warrants caution, and the presence of fluid around the BT may reflect a physiologic adaptation to racing, rather than a pathologic change in ultra-endurance Alaskan sled-dogs.