Introduction: Total elbow replacement (TER) may be considered to improve pain and function in dogs
with elbow osteoarthritis. The TATE BioMedtrix implant is a cementless, semi-constrained
prosthesis with humeral and radioulnar components, designed for TER in canines. This
study aimed to evaluate the alignment accuracy of TATE TER using virtual surgical
planning (VSP) and novel 3D-printed patient-specific guides (PSG) via either a medial
or lateral surgical approach. We hypothesized that a lateral approach would allow
for more accurate positioning of the PSG, resulting in improved accuracy in COR postplacement
and osteotomy location.
Materials and Methods: This was a prospective cadaveric study. All dogs underwent preoperative CT imaging
of bilateral thoracic limbs and PSGs were designed. TER was performed via either a
medial or lateral approach. Postoperatively, radiographs were obtained to assess COR
postlocation and implant positioning.
Results: Twelve cadaveric dogs were used. Mean COR post entry location did not differ among
techniques. The mean screw angle deviation was greater in the lateral approach group.
Mean axial location, angulation of the osteotomy, and prosthesis placement deviation
did not differ among groups (p = 0.967, p = 0.582, p = 0.244, respectively).
Discussion/Conclusion: Screw angulation in the lateral approach group was significantly greater than in
the medial approach group. Theoretically, proximal angulation of the COR post from
a lateral approach may result in varus alignment of the prosthesis; however, this
was not observed in our study. Design modifications to the lateral PSG should be considered
to increase the accuracy of COR placement. Based on these preliminary findings, both
surgical approaches appear to be acceptable surgical options.
Acknowledgment
This study was partially funded in part by Movora, who covered the cost of medical
imaging, surgical instruments and implants, and investigator travel, and by Thrive,
who covered the cost of medical 3D printing.
