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Chen, et al.
A osseointegration in animal experiments and requires
long-term evaluation.
Our study has some limitations. The central hexagonal
driver within the specific sleeve instrument was used to drive
the internal screw to open the wing mechanism. However,
only 2-mm hexagonal head of the central driver must be
carefully under appropriate insertion force to prevent the
head from slipping or breaking and make it impossible to
push the wings away. Furthermore, our animal experiments
focused on the normal bone to evaluate the functionality
of osseointegration after anchor implantation. A detailed
animal model of osteoporosis needs to be used to evaluate
whether the failure strength of the newly-designed anchor is
improved and the state of osseointegration.
B
5. Conclusion
A novel HSA with wing structure mechanism with dual-
threaded was developed integrating 3D printing and
mechanic milling and the wing of HSA can be opened by an
internal screw to increase the holding power for osteoporosis
patient when necessary. Results of static and after dynamic
load pullout tests for severe and normal osteoporosis
showed that the failure strengths of HSA with and without
the wing open were significantly higher (P < 0.05) than
that of CSA. Histomorphometrical evaluation revealed that
the effects of new bone ingrowth along the anchor contour
for CSA and HSA were both approximately 20%, with no
statistically significant difference.

Funding
Figure 6. (A) A slider was designed in the hybrid suture anchor.
(B) Wing-open failure as the slider was prone to binding. This study is supported in part by MOST 109-2314-B-
038 -026 -MY3 and 109-2221-E-010 -002 -MY3, Taiwan.
were higher than that of the normal osteoporosis (1.81 for Conflict of interest
with the wing open and 1.54 for without the wing open).
A similar trend was also found in the dynamic tests. This No conflict of interest was reported by all authors.
result implied that our new design was more effective in
the severe osteoporosis case. The more interesting part Author contributions
of the pullout test was that after the dynamic test, failure Supervision: Chun-Li Lin
strength was higher than static failure strength for both the Conceptualization: Chih-Hwa Chen and Chun-Li Lin
control group and the newly-designed anchor. This was Investigation: Yu-San Chen, Kuan Hao Chen, Shao-Fu
because the UHMWPE fiber of the suture was affected Huang, Hsin-Ru Hsueh, Cun-Bin Li
by high temperature and high strain rate, and the tensile Methodology: Yu-San Chen, Kuan Hao Chen, Shao-Fu
strength of the suture increased as the strain rate increased. Huang Hsin-Ru Hsueh and Cun-Bin Li
Results from histomorphometrical evaluation Formal analysis: Wen-Jen Chang and Yu-San Chen6
revealed that the effects of new bone ingrowth along Writing – original draft: Chih-Hwa Chen and Chun-Li
the anchor contour, 1-mm outward for the control Lin
and newly-designed anchor were both approximately Writing – review and editing: Chih-Hwa Chen and Chun-
20%, with no statistically significant difference. Li Lin
Thus, our newly-designed anchor can achieve initial
osseointegration on the anchor-bone interface after References
surgery and be used in the clinic. However, the newly-
designed anchor, with the wing open and three surface 1. Chaudhry S, Dehne K, Hussain F, 2019, A Review of Suture
holes of 600-μm diameter, did not exhibit better Anchors. Orthop Trauma, 33:263–70.

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