Equine studies
Outcome measures regarding symptom-modifying changes were described in five equine studies (Kay et al., 2008; de Grauw et al., 2016; Ekstrand et al., 2019; Kearney et al., 2021; Clifford et al., 2021), and these included lameness, joint circumference, edema or effusion, range of motion (ROM), response to flexion test, skin temperature, and composite welfare score.
TA improved lameness by one or more grades in two studies with follow-ups of 11 days and three weeks (Kay et al., 2008; de Grauw et al., 2016). In another study, most horses treated with TA did not show improvement in lameness, with some even worsening at a 6-week follow-up (Clifford et al., 2021). Similarly, joint effusion showed improvements in a shorter-term study (three weeks) (de Grauw et al., 2016) with no significant changes for more extended periods (six weeks) (Clifford et al., 2021). Improvements in joint edema and ROM were reported following TA injection in one paper (11 days) (Kay et al., 2008) with no changes in joint circumference (Kay et al., 2008; Kearney et al., 2021) or composite welfare score (five weeks) (Kearney et al., 2021). Response to flexion was assessed by one study with a maximum of 6-week follow-up, and the authors reported no changes or worsening of response in most cases (Clifford et al., 2021).
DEX was assessed by one study, which demonstrated improved lameness (0.5–1 grade, 30-hour follow-up); however, the authors found no changes in joint circumference or skin temperature (74-hour follow-up) (Ekstrand et al., 2019). There were no studies reporting symptom-modifying osteoarthritic (SMOA) effects following a single IA injection of other corticosteroid types in horses.