Detection of a radiographically occult fracture of the lateral palmar process of the distal phalanx in a horse using computed tomography.

This study investigates a suspected injury to the bone structure called the distal phalanx in a horse. The horse was first examined using x-ray imaging but the specific injury went undetected. Computed tomography (CT) was later used to accurately diagnose the issue as an incomplete fracture of the distal phalanx, demonstrating CT’s value in identifying complicated fractures.

Research Overview

• The research revolves around a case of a horse that had a suspected injury in its distal phalanx (the last bone of the horse’s foot), marked by onset of lameness (difficulty in moving due to discomfort or pain in the limb).
• The horse underwent two radiographic examinations (also known as x-ray imaging), on the second and nineteenth day following the onset of the noted lameness. Both examinations did not yield any conclusive diagnosis of the problem.

Computed Tomography Use

• On the twenty-fifth day after the horse began showing signs of lameness, the researchers used computed tomography (CT) to further investigate the suspected issue.
• Computed Tomography uses a series of x-ray measurements taken from different angles to produce cross-sectional images of specific areas of a scanned object, like the body part of a horse in this case. This allows clearer and more specific images as compared to standard x-ray imaging.
• The CT scan diagnosed an incomplete fracture of the lateral wing of the distal phalanx, a finding that was previously missed by x-ray imaging. Additionally, it was established that the fracture did not affect the joint or the palmar cortex throughout its length – an important detail for understanding the prognosis (future outcome) of the horse’s condition.

Further Radiography

• A day after the CT examination, a new radiographic projection (another x-ray examination, but taken from a different, specific angle) was carried out. This new projection was informed by the detailed information about the fracture’s geometric pattern that was gathered through the previous CT scan.
• This subsequent x-ray examination revealed a radiolucent area that indicated the presence of the wing fracture, further confirming the accuracy of the CT imaging.

Conclusion

• The research emphasizes the value of computed tomography in correctly diagnosing geometrically complicated fractures such as the nonarticular oblique fracture of the palmar process of the pedal bone in a horse, which was the case in this study.
• This case emphasizes CT scanning’s superiority to x-ray imaging for identifying complicated fractures that may remain undetected with conventional radiography alone.