My most challenging feline fracture case

A male castrated 7-year-old domestic shorthair cat was presented as an emergency due to non-weight-bearing left forelimb lameness and a wound on that leg. At presentation the cat was hemodynamically stable but showed increased breathing rate. There was a 4/6 systolic heart murmur. Thoracic radiographs and blood work were unremarkable. The area around the distal humerus was markedly swollen, there was crepitation proximal to the elbow, and a wound was present both laterally and medially. Radiographs of the left humerus revealed a distal diaphyseal comminuted fracture caused by a gunshot injury. The articular surface was not perfectly visible due to an overlying bullet, but was deemed intact.

Emergency treatment consisted of iv fluid administration and iv application of amoxicillin-clavulanic acid and methadone. The cat was taken to surgery the next morning. A lateral approach (open but do not touch) was used to access the distal humeral diaphysis. The radial nerve was identified and was bruised but intact. The bullet fragments were not visible and soft tissues were not further explored to search for them. An approximately 1cm long bone defect was present in the cranial cortex. The fracture was stabilized with two 2.0mm locking plates applied orthogonal to each other (lateral and cranial). The area was thoroughly flushed, a bacterial swab was taken for bacteriology and sensitivity testing and the surgical wound was primarily closed.

The cat was released from hospital the next evening with oral meloxicam and amoxicillin/clavulanic acid for one week. The bacteriologic exit culture returned negative. At time of stitch removal the cat had started weight-bearing. Four weeks postoperatively the cat was walking with a grade 2/5 lameness. Range of motion of elbow and shoulder joints were normal and there was no significant swelling or pain. Radiographic healing was difficult to assess due to the overlying metal. It was suggested to keep the cat indoors for another 2 weeks. At the time of writing (8 weeks postoperatively) the owner reported that the cat was ambulating well and was going outside again, but still had a slight limp and had developed a wound on the paw. Final follow-up is unknown at the time of writing. [...]