Postanesthetic Neuropathy/Myopathy in the Nondependent Forelimb in 4 Horses

Postanesthetic lameness in the form of myopathy or neuropathy is a well-known complication associated with equine general anesthesia and is most often reported in the dependent limb of horses treated in lateral recumbency. The aim of this case series was to report clinical data of 4 horses treated under general anesthesia in lateral recumbency and that developed postanesthetic neuropathy/myopathy in the nondependent forelimb. With anti-inflammatory and analgesic medical treatment, locomotor problems associated with neuropathy/myopathy resolved after 12–24 hours in all cases. The pathogenesis remains unclear. A first hypothesis may be the decreased hydrostatic pressure in limb vessels elevated above the level of the heart, and consequent reduction of muscle perfusion. Second, abduction and/or endorotation of the upper forelimb may have caused injury to the brachial plexus. Therefore, positioning of the nondependent forelimb should be done judiciously and may be the subject of further research.