Diagnostics & Imaging
Diagnostic Musculoskeletal Ultrasound
Ultrasound is a diagnostic imaging technique that has a broad range of applications. For decades it has been used in the diagnosis of musculoskeletal injuries, especially when there is injury to tendons and ligaments. With an increasing awareness of soft tissue injury by veterinarians specializing in canine sports medicine, orthopedics and rehabilitation, diagnostic ultrasound is now being utilized to diagnose them. Injuries of the following structures are now being evaluated ultrasonongraphically in dogs by those experienced in the technique:
- supraspinatus tendon
- biceps tendon
- achilles tendon
- infraspinatus tendon
- patellar ligaments
- collateral ligaments
This list is just a few examples of the more common strucutres that are evaluated with ultrasound in the dog, but many more are possible!
Advantages of Ultrasound
There are multiple advantages over other diagnostic imaging modalities for the evaluation of soft tissue injuries in dogs. Radiographs are the cornerstone of an orthopedic evaluation, but where they tell you a lot about bone, they tell you relatively little about soft tissue injury. Ultrasound, on the other hand can more fully evaluate soft tissue injuries unlike radiographs. A significant amount of detail in multiple angles can be obtained by ultrasound of the affected structure. It does not achieve the detail of Magnetic Resonance Imaging (MRI) which will remain the gold standard for evaluating both bone and soft tissue structures, but it does have some advantages. Where MRI requires that that patient be anesthetized for the study, ultrasound can be performed in the awake or slightly sedated patient. MRI are also very expensive relative to ultrasound. In order to assess whether a injury has healed over time, follow-up exams are necessary. Multiple follow-up exams with MRI may not be practical, but multiple ultrasound exams to follow the progress are easily performed.
Radiographs are the most frequently used diagnostic images in veterinary medicine. Radiographs, or x-rays, are a quick, simple way to assess your pet’s bones and joints. They offer the benefit of showing a wide viewing area, such as a whole knee joint or the whole pelvis, which makes it easier to gather more information in one picture. Radiographs can often be taken without sedation, depending on the patient. Sometimes, multiple views are needed to fully evaluate the targeted area. At FVRSM, we use a digital radiography system, which means we get images instantly and can adjust exposure, contrast, and other features on our computer.
An unbiased assessment of your dog’s health and structure is important for making decisions regarding breeding. We regularly perform radiographs for submission to OFA and/or PennHIP.
OFA (Orthopedic Foundation for Animals) is an organization that is dedicated to genetic testing and research.Hips are most commonly tested, but elbows, shoulders, and patellas are recommended for many breeds. Radiographs submitted to the OFA are evaluated by three independent board-certified radiologists and graded based on factors such as laxity, coverage, and remodeling. OFA keeps a database of scores by breed, which allows breeders to research lines and make appropriate breeding decisions. OFA radiographs can be taken without sedation as long as the patient is not stressed by being handled. This makes them the most popular, and affordable, means of testing orthopedic health. However, the scores are determined subjectively, so there is a risk of human error and bias.
Additional information on OFA’s testing and procedures can be found here.
PennHIP is an imaging service through Antech Diagnostics that specializes in assessing hip conformation and health. Dogs can receive PennHIP scores as early as 16 weeks of age. Radiographs submitted for review must be performed by a PennHIP-certified veterinarian. As opposed to OFA, PennHIP assessments consist of a series of three views – an extension, a compression, and a distraction view. The extension view is a standard position for pelvic x-rays that allows a general picture of the hips’ overall structure. The compression and distraction views allow accurate measurements to be made of how well the hip socket fits together. Measurements gathered from these images are calculated to form a Distraction Index, or D.I. PennHIP is a valuable assessment method because it uses objective, quantitative data, as opposed to subjective reviews. Additionally, having a DI number allows breeders to compare their dog to others of the same breed to determine if their hips are the same, better, or worse than the average within the breed. Since the submission consists of three views that require quite a bit of positioning and muscle relaxation, a light sedation is required.
Additional information on PennHIP testing and procedures can be found here.
Once radiographs are submitted to OFA and/or PennHIP, results are generally available within 2-3 weeks. Dr. Brown can counsel you on their findings and what it means for your dog’s health, performance, and breeding potential.
Responsible and ethical breeders perform necessary genetic testing on their breeding dogs to ensure that they are not producing animals with preventable diseases or conditions. Genetic tests recommended for each breed can generally be found on the national breed club’s website.
As a breeder of working Labradors, Dr. Brown is is experienced in submitting samples for testing through OFA and other laboratories, as well as making decisions based on the results. She is available for sample collection and pre-breeding consultations.