Ankylosis of the Digit Bones in Six Culling Lame Cows

Objective- To review the six cases for determination the radiological, pathological and clinical features of bony ankylosis of the interphalangeal joint. Design- Cross-sectional and Observational study Animal- Six Culling Lame Dairy Cows Procedures- Forty one culled lame cows of ۱۱۳۵ culled cows having digit disorders which were randomly selected for clinical and radiographic and pathological purpose. Aamong ۴۱ culled lame cows; six cases were affected by bony ankylosis. After recording information for each cow, diseased digit was amputated and carried to the VeterinaryTeaching Hospital, Radiology Department for more detailed radiographical as well as pathological studies. Results- In ۶ (۱۴.۶%) cases of the culled lame cows, the signs of ankylosis and injuries in their sole surface at zone ۲, ۴, ۵ and ۶ were prevailed. All of the ankylosed cases wereinvolved in the lateral claw of the hindlimbs. Pathological findings recorded from ۶ caseshad some similarities to the solar surface had no natural wearing and showed an increasein thickness of the keratinized tissues. Widening of the periople and swelling of the heelarea in the involved digit were the permanent features of the culled lame cows. Morphopathologic finding recorded from ۶ cases strongly illustrated bony ankylosisbetween (P۱+ P۲ bone, P۳+ distal sesamoid bone, P۲+ P۳ bone+ distal sesamoid bone,P۲+ distal sesamoid bone) was observed. Radiographic images taken from the involved digits of the ۶ culled lame cows depicted a quite wide range of radiographic signs such as soft tissue swelling, new bone formation and gas density. Conclusion and Clinical Relevance- Radiological and morphopathological pattern ofboney structures in bony ankylosis indicates that noninfectious factors like subluxation ofthe joint beside ascending infection under hoof surface can stimulate bridge-likeperiosteal proliferation in the periarticular surface, and they eventually result in ankylosissuch as subluxation of the joint between P۲ and P۳ bones. However, ankylosis of thecoffin joint is a factor that causes subluxation in the pastern joint.