Page 193 - IJB-9-6

International Journal of Bioprinting 3D-printed assembly anatomical patella fracture bone plate

The patella fragments were also fixed by bone screws and Acknowledgments
AATBP. This was clearly different from the fixation using None.
TBW without holding power and suggested that AATBP
can be further applied to in vivo tests. Funding
The FE simulation and biomechanical test results
showed the same trend, i.e., fractured gap distances at the This study is supported in part by MOST project
108-2622-E-010-001-CC2 and 110-2222-E-032-003-MY2,
medial/lateral sides for TBW were both higher than that of Taiwan.
AATBP fixation models. The TBW fixation cannot hold the
fracture segments of the patella efficiency, and the maximum Conflict of interest
bone stress found around the medical wire inserted into
the patella might cause the fracture segments to slide. The The authors declare no conflicts of interest.
bone stress concentration for the AATMP fixation was
found around the screw. The corresponding maximum Author contributions
stress value was 5.69 MPa and at the lateral bottom screw Conceptualization: C.Y. Liao, Chun-Li Lin
hole. Although the maximum stress value was much lower Investigation: Shao-Fu Huang, Wei-Che Tsai, Yu-Hui Zeng,
than the tensile ultimate strength (135 MPa), it should be Chia-Hsuan Li
noted that it may cause locking screw loosening . Methodology: Chun-Li Lin
[24]
The patella fracture types are not limited to transverse Writing – original draft: C.Y. Liao, Chun-Li Lin
fractures but also include other forms of comminuted Writing – review & editing: C.Y. Liao, Chun-Li Lin
fractures or proximal/distal fractures. The main objective
of surgical treatment is to restore these comminuted bones Ethics approval and consent to participate
to their original anatomical positions while maintaining Not applicable.
their stability. A fixation bone plate designed to have good
encircling energy (holding power) for the fractured patella Consent for publication
is recommended. Our AATBP and the experimental/
simulation results presented herein manifest this property Not applicable.
and can be applied to the main patella fracture of the
transverse type, as well as other fracture forms in the future. Availability of data

Although the AATBP was designed with an anatomical Not applicable.
contour and has been confirmed to be adaptable for use,
this bone plate may not enable clinicians to do much References
manual bending during surgery due to the limitations of 1. Lee KH, Lee Y, Lee YH, et al., 2019, Biomechanical
3D-printed materials and post-manufacturing processing. comparison of three tension band wiring techniques
More rigorous in vivo experiments may be required to for transverse fracture of patella: Kirschner wires,
further confirm the clinical utility of the AATBP, although cannulated screws, and ring pins, J Orthop Surg, 27(3):
the biomechanical stability was confirmed in this study. 2309499019882140.
2. Gibert S, Kowaleski MP, Matthys R, et al., 2016,
5. Conclusion Biomechanical comparison of pin and tension-band
This study confirmed that the thin structural bone plate wire fixation with a prototype locking plate fixation in a
for patella fixation, comprising anatomical surface, hook, transverse canine patellar fracture model. Vet Comp Orthop
Traumatol, 29(1): 20–28.
small cone, and size-adjustable ratchet mechanism, can
be fabricated using 3D metal printing with acceptable 3. Wild M, Eichler C, Thelen S, et al., 2010, Fixed-angle plate
manufacturing error and reasonable anatomical surface/ osteosynthesis of the patella - an alternative to tension
thin bone plate assembly fitness, mechanical bending wiring? Clin Biomech, 25(4): 341–347.
strength, and surface roughness. The biomechanical 4. Thelen S, Schneppendahl J, Jopen E, et al., 2012,
cyclic test results showed that the fracture gap between Biomechanical cadaver testing of a fixed-angle plate
two AATBP fixation fracture segments after cyclic loads in comparison to tension wiring and screw fixation in
was smaller and superior to conventional TBW for patella transverse patella fractures. Injury, 43(8): 1290–1295.
transverse fractures. The FE simulation result addressed 5. Thelen S, Schneppendahl J, Baumgärtner R, et al., 2013,
the stress concentration around the screw holes and noted Cyclic long-term loading of a bilateral fixed-angle plate
the high risk for screw loosening. in comparison with tension band wiring with K-wires or

Volume 9 Issue 6 (2023) 185 https://doi.org/10.36922/ijb.0117