The prestigious American Veterinary Medicine Association has published another 2.5% iPAAG (ArthramidVet®) study conducted by IMS Vet Directors Dr Jason Lowe and Dr Leigh de Clifford, in keeping with our goal of continued learning and sharing of knowledge about ArthramidVet®.

Trial Design

The study involved 13 “normal” fetlock or carpus joints in 10 horses and included assessments on Days 0, 14, 42 and 90. Treatment joints received 2 or 4mL ArthramidVet®.

Results

Synovial histology demonstrated increased cellular infiltration of macrophages, villous hyperplasia and vascularisation with 2.5% iPAAG.
Scanning electron microscopy confirmed extensive tissue integration of 2.5% iPAAG as a 3D scaffolding structure with intact cross-linked strands.
No significant differences were found between control and treated joints on clinical examination, arthrocentesis cytology or gross post-mortem.

Conclusion

This study confirms that an IA injection of 2.5% iPAAG induces a low-level foreign body response which is predominately macrophage-driven, with no evidence of fibrosis or mineralization.

By 14 days, the gel is fully integrated into the subintima, with no free gel remaining in the joint cavity.

These findings support previous studies in demonstrating that ArthramidVet® is safe and induces significant intra-articular effects with a single injection.

REFERENCE: Lowe J, de Clifford L, Julian A, Koene M. Histologic and cytologic changes in normal equine joints after injection with 2.5% injectable polyacrylamide hydrogel reveal low-level macrophage-driven foreign body response. JAVMA 2024

Full article: https://avmajournals.avma.org/view/journals/javma/aop/javma.23.10.0553/javma.23.10.0553.xml?rskey=qFifFa&result=5