Partial tarsal arthrodesis with closing wedge ostectomy for treatment of bilateral twisted leg deformity in a cat.

A 5-month-old male domestic shorthair cat was presented with severe bilateral hind-limb deformities that caused the cat to walk on the dorsal aspect of the metatarsals. Computed tomography (CT) images revealed that the calcaneus was externally rotated, and the distal end of the calcaneus was turned medially to the talus in both hind limbs. The cat was diagnosed with twisted leg deformity, a congenital tarsal hyperextension deformity (clubfoot). Based on CT images, closing wedge ostectomy was done at the level of the tarsometatarsal joint with the wider part facing laterally. Partial transection of the common calcaneal tendon was not performed. Nine weeks after surgery, the cat was able to walk and jump, with its paws correctly placed on the ground, despite the limited range of motion in the tarsal joints. Based on radiographs with maximum tarsal flexion, the angle of the partial tarsal arthrodesis limited the range of motion. This is apparently the first case report describing CT images and closing wedge ostectomy in a cat with twisted leg deformity. Key clinical message: This article reports the findings obtained from CT imaging of a cat with twisted leg deformity. The current case was successfully managed by closing wedge ostectomy without partial transection of the common calcaneal tendon.