3D-printed, patient-specific cutting guides improve femoral and tibial cut alignment in canine total knee replacement

Agnieszka B Fracka, Bill Oxley, Matthew J Allen
Vet Surg. 2023 Apr 28. doi: 10.1111/vsu.13963.

Objectives: The purpose of this cadaveric study was to determine whether patient-specific guides (PSGs) improve the accuracy of tibial and femoral cut alignment in canine total knee replacement (TKR), as compared with generic cutting guides.

Study design: Original research.

Animals: Sixteen pelvic limbs from skeletally mature medium- to large-breed canine cadavers.

Methods: Specimens were randomly allocated to one of two groups (PSG or Generic; N = 8/group). In the Generic group, femoral and tibial ostectomies were made using the standard canine TKR femoral cutting blocks and tibial alignment guide. In the PSG group, the cuts were made using a series of custom 3D-printed cutting guides. "Planned" and "actual" tibial and femoral cut alignments were compared in the frontal and sagittal planes, and errors were calculated by subtracting actual from planned values.

Results: Use of 3D-printed PSGs improved tibial cut alignment in the frontal plane but not the sagittal plane. PSGs also improved the alignment of the cranial and distal femoral ostectomies but did not impact varus-valgus alignment.

Conclusions: These findings support the use of PSGs for TKR in dogs. Clinical trials are now needed to determine whether the benefits of PSGs translate into measurable improvements in joint function and implant longevity.

Clinical significance: PSGs have the potential to improve femoral and tibial component alignment in canine TKR.