Competing interests
The author(s) declare that they have no competing interests.
Authors' contributions
BJ designed the study and developed the gait and posture scoring methods. RKK examined and scored the joint lesions with assistance from HEJ. RKK and BJ performed the statistical analysis and RKK, BJ, and HEJ drafted the manuscript. All authors read and approved the final manuscript.
Acknowledgements
This investigation was supported by the Federation of Danish Pig Producers and Slaughterhouses. The investigation was carried out in the research herd 'Grønhøj' owned by the Federation of Danish Pig Producers and Slaughterhouses. Villy Mundt carried out the gait scoring. The staff of this herd and the staff of the Danish Crown Slaughterhouse in Sæby helped during the practical part of the investigation. They are all gratefully acknowledged for their assistance.