Russian Study Reports Partial Walking Recovery in Three Pigs After Complete Spinal Cord Cut

Researchers led by Michael Lebenstein-Gumovski at the Sklifosovsky Institute for Emergency Medicine in Russia restored walking ability in three pigs whose spinal cords had been completely severed. The study, published in 2026, used a fusogen mixture of polyethylene glycol and chitosan injected at the injury site.

The team anaesthetised the animals, removed the bony arch over the spinal cord, cooled the area for one minute and cut the cord in the mid-back region.

This replicated a severe injury that severs all connection between the brain and the body below the abdomen. Three pigs received the fusogen, which was also infused into the blood for one week after surgery. Two control pigs received identical surgery and post-operative care but no fusogen.

All animals underwent twice-daily electrostimulation of each limb and received drugs to limit inflammation and bowel obstruction. Immediately after surgery every pig showed motor and sensory paraplegia in the lower limbs and pelvis. The two control animals remained paralysed for the full 60 days.

In the treated group one pig moved a hind limb on day two and all three responded to pinpricks in parts of the hind legs by the same day. One treated pig attempted to stand by day seven. By day 60 all three walked unsteadily, regained pelvic control and showed some touch sensitivity.

Tissue analysis later found reduced degeneration at the lesion and numerous twisted, thickened axons forming bridges across the cut. The researchers stated that polyethylene glycol helps seal damaged nerves and may promote axon fusion, while chitosan seals membranes and supplies a scaffold.