Eel Orthopedic Surgery at the New York Aquarium


A mature (5.7kg) American conger eel (Conger oceanicus) was immobilized for diagnostic evaluation due to two weeks of anorexia and pale discoloration. While anesthetized, radiographs, ultrasound and bloodwork were collected. The eel was found to have an upper jaw injury and a fracture at the tip of the maxilla separating the upper jaws. The recent anorexia was likely due to the jaw fracture, and it was not known how that injury occurred. Fracture repair and stabilization would give the eel the best chance for healing and recovery. 

As this is not a common procedure in fish, creativity and “thinking outside the box” was necessary for surgical planning. As hardware is typically not available for orthopedic surgery in fish, bone pins and external fixators had to be constructed out of other common medical supplies. For the surgery the eel was maintained on a recirculating fish anesthesia table to keep her out of the water, but with anesthetic water continually flowing over the gills. To stabilize the fractured ends of the bones, bone tunnels were created and suture was passed through the tunnels to suture the bones together. Plastic tubing was used as an external fixator that conformed around the shape of the upper jaw on both sides and this was secured with small gauge needles used as bone pins through the plastic tubing and into the upper jaw bones, with the tubing made rigid by injecting dental composite through the fluid line. This provided rigid stabilization of the fracture. 

The eel recovered well from anesthesia and was put on antibiotics, opioid analgesics, and anti-inflammatories post-operatively. Because this species is a cold water species, healing will be prolonged, but we hope that with the jaw stabilized the eel will resume eating while the fracture heals.

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