Radiographic appearance of the navicular bone and distal interphalangeal joint and their relationship with ossification of the collateral cartilages of the distal phalanx in Finnhorse cadaver forefeet.

The research article investigates the correlation between the radiographic appearance of the navicular bone, distal interphalangeal joint, and the ossification of the collateral cartilages of the distal phalanx in the Finnhorse cadaver forefeet.

Radiographic Findings

• The article evaluated radiographic findings in the navicular bone and distal interphalangeal joint, in addition to assessing the ossification status of the collateral cartilages of the distal phalanx. This was performed on 100 Finnhorse cadaver forefeet.
• The most common shapes found in the proximal articular margin of the navicular bone were straight and convex.
• Navicular bone remodeling was observed often, especially on the lateral extremity.
• The study found that while the distal flexor margin showed irregularity in several feet, there were no bony fragments identifiable.

Synovial Invaginations and Flexor Cortex

• Large, rounded, or lollipop-shaped synovial invaginations were identified in only six feet.
• The thickness of the flexor cortex varied considerably among the samples.
• The corticomedullary junction in nine feet was found to be either uni- or bilaterally indistinct.
• Although the sagittal ridge of the flexor cortex was mostly flat, it varied and sometimes appeared locally irregular or indistinct in 17 feet. However, changes elsewhere along the flexor cortex were uncommon.

Entheseophytosis and Ossification

• The research noted prevalent occurrences of osteophytosis on the dorsal, as well as palmar margins of the distal interphalangeal joint. Entheseophytosis was also common on the dorsal area of the middle phalanx and on the extensor process of the distal phalanx.
• A significant ossification of the collateral cartilages, described as “possibly significant” which could be high sidebones or separate centers of ossification, was present in 36 feet.
• All grades of ossification in the proximal/palmaroproximal direction plus palmar ossification were observed.
• The study found a statistically significant relationship between entheseophytosis on the proximal flexor margin of the navicular bone and “possibly significant” ossification.

Final Observations

• Feet with a relatively long distal phalanx, suggestive of palmar ossification, commonly exhibited osteophytosis on the palmarodistal margin of the middle phalanx.
• The research concludes that there appeared to be no association between radiographic changes in the navicular bone or distal interphalangeal joint with ossification of the collateral cartilages of the distal phalanx in Finnhorses.