Clinical Evaluation of Iliopsoas Strain with Findings from Diagnostic Musculoskeletal Ultrasound in Agility Performance Canines – 73 Cases

Abstract

Objective:Iliopsoas injury and strain is a commonly diagnosed disease process, especially amongst working and sporting canines. There has been very little published literature regarding iliopsoas injuries and there is no information regarding the ultrasound evaluation of abnormal iliopsoas muscles. This manuscript is intended to describe the ultrasound findings in 73 canine agility athletes who had physical examination findings consistent with iliopsoas discomfort. The population was chosen given the high incidence of these animals for the development of iliopsoas injury; likely due to repetitive stress. Methods:Medical records of 73 agility performance canines that underwent musculoskeletal ultrasound evaluation of bilateral iliopsoas muscle groups were retrospectively reviewed. Data included signalment, previous radiographic findings, and ultrasound findings. A 3-tier grading scheme for acute strains was used while the practitioner also evaluated for evidence of chronic injury and bursitis. Results:The majority of pathologies were localised to the tendon of insertion, with the majority being low grade I-II strains (80.8%). Tendon fibre disruption (71.2%) and indistinct hypoechoic lesions (91.8%) were the most common of acute changes noted. Hyperechoic chronic changes were noted in 84.9 percent of cases. Acute and chronic changes were commonly seen together (62.8%). Conclusion:Diagnostic musculoskeletal ultrasound was used to identify lesions of the iliopsoas tendon consistent with acute and chronic injury, as well as identifying the region of pathology. The majority of agility performance dogs had low grade acute strains based on the tiered system, with mixed acute and chronic lesions being noted frequently. Application:Diagnostic musculoskeletal ultrasound provides a non-invasive diagnostic modality for patients suspected of having an iliopsoas strain.

Observational Study on Lameness Recovery in 10 Dogs Affected by Iliopsoas Injury and Submitted to a Physiotherapeutic Approach

“…This lesion is commonly characterized by a poor visualization of the muscle-tendon fibers, with a moderate-to-severe decrease in echogenicity [18]. Cullen and collaborators [6] reported similar findings in dogs with traumatic injury to the iliopsoas muscle. No other advanced diagnostic imaging exams were performed in our cases [6].…”

“…However, border collie was the most represented breed in this study; only three dogs were reported as "other breed". This breed is widely involved in most canine sports [6,13], and it is the breed most commonly injured during agility, more than would be expected [3]. The border collie has always shown a great ability for training and cooperation with humans.…”

“…Furthermore, 70% of our cases were athletic dogs, and a traumatic injury had been reported in their history; this phenomenon has been reported in the literature [6,15]. Iliopsoas muscle strains are believed to occur during eccentric contraction, when the muscle is contracting while lengthening [4,16].…”

“…Moreover, dogs with mild injuries may experience a gradual improvement over time, but a decrease in performance during training or competition is often reported [3,4]. Lesions of the iliopsoas muscle are generally classified into three grades based on severity: grade 1 (mild), grade 2 (moderate), and grade 3 (severe) [5][6][7].…”

“…Diagnostic imaging is also used; it can show the degree and the site of the muscle lesion. These techniques mainly include ultrasound and magnetic resonance imaging, frequently associated with laboratory tests, although these tests are often non-specific for particular lesions [6,12].…”