Long-term radiographic appearance of a bioabsorbable biocomposite tibial tuberosity advancement cage implant

Authors: 
Ferrell CL, Barnhart MD, Watson AT, Barron-Chapman ML, Naber SJ.
Aust Vet J. 2019 Dec 2. doi: 10.1111/avj.12894.

OBJECTIVE: To report the radiographic appearance of a bioabsorbable biocomposite tibial tuberosity advancement cage at least 1 year after implantation. Design Retrospective case series.

METHODS: Medical records (February 2014-March 2015) of dogs receiving a biocomposite tibial tuberosity advancement cage were reviewed. Cases were selected if they had undergone surgery at least 1 year before the selection, no additional surgeries were performed, and no known surgical site infection had occurred. Medical record information assessed included signalment, body weight (kg), affected stifle joint (left or right), date of original surgery and the size of biocomposite cage used (9 or 12 mm). Radiographs were evaluated by two blinded radiologists who calculated percentages of osteolucency present in five zones around the cage and assigned a numerical score based on these calculations. Variables were evaluated statistically for effect on lucency percentage and numerical score.

RESULTS: Fifty dogs were included. Zone 5 (caudoproximal area) was found to have the lowest lucency percentage and score and zone 3 (distal area) had the highest lucency percentage and score. Twelve-millimetre cages were significantly associated with a higher lucency numerical score than 9 mm cages.

CONCLUSION: A biocomposite tibial tuberosity advancement cage was found to have variable amounts of radiographically apparent osseous integration at least 1 year after implantation.

Small animal: