Fractured Scapula in a Horse

A 5 year-old miniature horse presented to PHD Veterinary services for the complaint of forelimb lameness. The mini had been charged and mounted by a full grown horse 4 weeks prior and subsequently the mini was a grade 4 out 5 lame in the right forelimb at the walk. The referring veterinarian examined the mini on the day of the injury and radiographed the shoulder joint. There were no radiographic abnormalities noted. Although the lameness was slowly resolving, the owner and referring veterinarian elected for an ultrasound of the shoulder region. On presentation, the mini was a grade 3/5 lame in the right forelimb at the walk. There was a firm swelling over the center of the right scapula and the mini was painful to direct pressure. There was no muscle atrophy noted and the ambulation of the limb was normal.
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Figure 1

In Figure 1, the spine of the scapula is imaged. The white structures correspond to bone. The yellow arrows point to multiple bone fragments. These ultrasound findings suggest that the spine of the scapula was crushed when the full grown horse mounted the mini. The image in Figure 2 corresponds to an equine scapula and the yellow arrows highlight the spine of the scapula as it extends nearly the length of the scapula.  In addition to the bone fragments of the spine of the scapula, the longitudinal scan of the scapula in Figure 3 suggests a fracture of the body of the scapula. There is a "step" or interruption of the bony margin which is indicated by the red arrow in Figure 3. 

Figure 2

Figure 3

 In Figure 4, the abnormal scapula (left image) is compared to the normal scapula (right image). Clearly, there are multiple bone fragments present at the site of the fractured scapula. The prognosis for this mini is good given time to heal. The mini is developing a firm, bony callous over the fracture site to stabilize the scapula and it's soundness has improved since the injury. It remains possible that the mini may develop a sequestrum (dead bone) due to the multiple bone fragments which would result in a draining wound. In addition, the fracture of the body of the scapula will need significant time to stabilize before the mini can return to full soundness. This type of injury would likely be more serious in a full size horse due to the weight of the horse. In addition, the radial and suprascapular nerves are often involved in these types of injuries resulting in muscle atrophy and difficulty in proper ambulation of the limb.

Figure 4

Drug Testing and Prepurchase Exams for Horses

A 10 year old, warm-blood mare presented to PHD veterinary services for a prepurchase exam. The standard exam, complete with limb flexion was performed and the mare was found to be completely sound and negative to limb flexion. The buyer requested baseline radiographs of both hocks and both front feet. In addition, it was strongly recommended that a drug screen of the mare's blood be performed for the detection of sedatives, anti-inflammatory medications and corticosteroids.
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Figure 1

Although the mare was sound and did not resent limb flexion, there was radiographic evidence of advanced osteoarthritis of the lower hock joints.  In Figures 1,2, and 4, the yellow arrows are pointing to radiographic changes consistent with arthritis along the front or dorsal aspect of the lower hock joints. There is new bone growth (osteophytes) and joint space narrowing. In addition, in Figure 3, the blue arrows are pointing to the area of sclerosis surrounding the lower hock joints which suggests chronicity of the arthritis and the apparent "fusion" of the distal hock joints. These radiographic changes are advanced and are surprising considering that the mare was sound for the prepurchase exam.

Figure 2

Figure 3

Even though the mare was sound, I did NOT pass this horse for sale and intended use based on radiographic findings and advised the buyer to at least wait for the drug screen results prior to making their decision!   The standard drug screen takes approximately 5-7 days for results to be reported. Interestingly, the mare's blood tested positive for high doses of an anti-inflammatory medication which likely explains why this horse was sound and negative to limb flexion even though she has advanced arthritis in the lower hock joints. This case represents yet another example of the importance of drug testing and base line radiographs for prepurchase exams!! Admittedly, it is a financial slippery slope once you begin the radiographic exam regarding how many areas to evaluate, however; areas of high probablity such as the hocks and front feet should always be considered!

Figure 4

Allergic Airway Disease in horses.

In the past 30 days (July 8 - August 8) I have examined 10 horses for the complaint of coughing and poor performance. The horses have ranged in age from 8 to 19 years of age. There has been no commonality with regards to sex or breed. However, they all live in Florida and it is the hottest month of the year!  Through a series of diagnostics which include a re-breathing exam, upper airway endoscopy, and trans-tracheal wash, all 10 horses have been diagnosed with allergic airway disease (AKA: heaves or COPD). None of these horses had previously been diagnosed with this condition. 
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Upper trachea with large amounts of sputum present.

Lower trachea with thickened mucosa due to chronic inflammation

Allergic airway disease in horses typically results in coughing, increased respiratory effort, increased "abdominal" breathing, exercise intolerance and weight loss. If not managed properly, the condition worsens from year to year and can result in the death of the horse!! I have posted a blog previously discussing this disease and how it should be diagnosed and treated. Please click on the link below to read my blog from last year regarding this condition.

Allergic Airway Disease in a Horse