IMPeek intramedullary rod use in a cat

You may remember our report of the first IMPeek case in a complex proximal tibial fracture in a cat about 6 weeks ago.

Our fist clinical case took a surprising turn for the worse 2 weeks after surgery. The client had failed to confine the cat as recommended and had allowed the protective Elizabethan collar to remain off after discharge from hospital. During this time the cat had been able to partially lick open the medial tibial incision and obtain a MRSP susceptible to marbofloxacin. On top of that, the cat had been able to jump onto and off furniture at home, leading to acute non-weight bearing at approximately the same time as the initial infection was diagnosed.

Radiographs (below) showed fissure propagation through the caudal half of the tibial metaphysis and caudal tilting of the tibial plateau due to quadriceps pull on the tibial crest. The LCP and IMPeek rod remain in place, holding together the otherwise unstable proximal fragment.  

Revision was performed with wide excision of the open wound and a cranial approach to the tibial crest. A 2.0mm 12 hole LCP was contoured to the cranial tibia and affixed with a combination of cortical and locking screws, with the goal of engaging the IMPeek rod where possible. Unfortunately 2 drill bits snapped off within the bone and could not be retrieved. A bone allograft was used to stimulate bone healing. A closed suction drain was placed subcutaneously to help resolve the deadspace after wide excision of the infected tissue.

Strict confinement to a cage and 24/7 placement of the Elizabethan collar were prescribed along with appropriate antibiotics and analgesics. A lateral splint was applied for 2 weeks with weekly changes performed. The 2 week post op recheck showed a healed skin incision with no evidence of active infection. Limb use was considered good, with mild discomfort and lameness appreciated. 

The 4 week post op recheck showed excellent limb use, no pain on palpation of the tibia and normal stifle range of motion. Progressive bone union and integration of the bone graft was appreciated. The implant position and bone alignment remain appropriate. 

It is anticipated that this fracture will likely take another 6-10 weeks to completely heal, during which time repeat radiographs will be taken roughly every 4 weeks to monitor union. 

We will repost in 4 weeks with updated images.