Radiographic measurements of Miniature Horse and Miniature Pony Feet

Reliable assessment of foot conformation is essential for podiatric management in Miniature Horses and Ponies, yet reference ranges and the reliability of radiographic measurements remain poorly defined.

This study quantified radiographic measurements of foot conformation in sound, skeletally mature Miniature Horses and Ponies and evaluated their agreement, reliability, and precision.

Standardised lateromedial and dorsopalmar/plantarodorsal radiographs were obtained from 30 Miniature Horses and Ponies. Two observers took 60 measurements from 10 sets of projections on three occasions. Reliability and precision were quantified using intraclass correlation coefficients (ICC) and within-subject coefficients of variation (CV), and agreement was assessed against ±5 % limits of agreement (LOA). These measurements were then obtained by a single observer from 30 horses. The median and 95 % confidence intervals (CI) of each measurement were calculated.

Most linear and angular measurements had moderate to excellent reliability (median ICC 0.86, interquartile range [IQR] 0.22) and precision (median CV 4 %, IQR 7 %) but exceeded ±5 % LOA. Hoof wall thickness ratios had good reliability (minimum ICC 0.69, 95 % CI 0.49-0.96), excellent precision (maximum CV 9 %, 95 % CI 2-11 %), and acceptable agreement (maximum LOA ±4.7 %, 95 % CI -0.11-0.09). Marginal means (95 %CIs) were: dorsal, forefeet 0.245 (0.237-0.253), hindfeet 0.240 (0.232-0.248); lateral, forefeet 0.186 (0.180-0.194), hindfeet 0.180 (0.173-0.186); medial, pre-trim 0.177 (0.171-0.183), post-trim 0.169 (0.163-0.175).

Hoof wall ratios provide consistent, repeatable radiographic measurements suitable for clinical use in skeletally mature Miniature Horses and Ponies, supporting objective laminitis screening and monitoring.