Adaptation of land treadmill scoring system for underwater treadmill in dogs with thoracolumbar intervertebral disc extrusion.

The underwater treadmill (UWTM) is utilized in dogs recovering from thoracolumbar intervertebral disc extrusion (TL-IVDE). Gait scoring is validated for dogs with TL-IVDE walking on the land treadmill (LT) but has not been reported for the UWTM. Our objective was to investigate if LT gait analysis could be applied to the UWTM and if non-ambulatory dogs walking unassisted on the UWTM, at a standardized water level, would be more likely to generate gait scores compared to on the LT. This was a prospective, observational study in dogs with TL-IVDE managed surigcally. At 0, 2, 4, 8 and 12 weeks post-operatively, paired video footage of dogs walking on the LT and UWTM (water level at the greater trochanter) was used to generate 0-100 stepping (SS) and coordination (regularity index, RI) scores. Scores were compared between treadmill type and over time. Twenty dogs were enrolled and seventy-eight paired recordings were available for review. Median gait scores increased over time but did not differ by treadmill type (P = 0.262 for SS, P = 0.533 for RI). Combining SS and RI, more recordings received scores of 0 for the LT (n = 58/156; 37.2 %) compared to the UWTM (n = 44/156; 28.2 %; P = 0.043). Scores of 0, at visits when there was at least movement present at multiple joints, was more common on the LT (n = 11/108; 10.2 %) compared to the UWTM (n = 2/108, 1.9 %; P = 0.026). In dogs recovering from TL-IVDE, LT-based gait scoring was feasible in dogs walking on the UWTM and might complement other gait analysis methods, especially for non-ambulatory dogs.