Page 17 - ARNM-2-2

Advances in Radiotherapy
& Nuclear Medicine CFR-PEEK: A systematic review

A B C D

E

Figure 2. Evidence of imaging artifact reduction by three different types of imaging modalities: (A) lateral X-ray; (B) anterior-posterior X-ray; (C) lateral
magnetic resonance imaging (MRI); (D) axial MRI; (E) axial computed tomography.

Typical treatment involves a combination of separation in a non-oncologic population and noted that at 2 years
surgery followed by radiation therapy for metastatic of follow-up, radiographic fusion was successful and the
epidural spinal cord compression. Given the multimodality clinical outcomes were deemed excellent or good in 76.9%
approach, the ability to monitor for local recurrence and of the patients (20/26). The findings from this study are in
30
tumor progression is crucial in its management. CFR-PEEK agreement with two other studies, supporting the long-term
offers significant utility over titanium in this regard; clinical outcomes or durability of CFR-PEEK in the spine. 31,32
however, the most important consideration is its durability The biocompatibility of CFR-PEEK is important as it
when compared to titanium. According to published
works, titanium hardware failure rates in spinal oncology allows the implant to work within the body without causing
were reported to be 4.2% (7/164), 6.6% (9/136), and 8.57% injury or activating an immunologic reaction. In terms of
(9/105). 26-28 To compare these two surgical materials, we the elastic modulus of different instrumentation materials,
reviewed four prospective and five retrospective studies. CFR-PEEK (3.5 gigapascals [GPa]) is the closest to human
Complications were presented in each of the 9 studies bone (12 – 20 GPa for cortical bone, and 1 GPa for cancellous
using CFR-PEEK (2050 screws) in 671 patients. Our bone), compared to other metals used for implants such as
33-35
analysis showed that the rates of hardware failure in CFR- titanium (106 – 155 GPa). These works, however, did not
PEEK instrumentation compared favorably with rates of determine if the similarity in elastic modulus to bone has any
hardware failure and screw loosening with titanium at significant implications for support its clinical use relative
3.2% and 3.48%, respectively. to other materials. Nevertheless, it is worth noting that the
modulus of carbon fiber can be adjusted to match that of
Two of the main biomechanical properties in foreign either type of bone. CFR-PEEK has also been shown to be
36
body implants are durability and biocompatibility. The highly biocompatible and chemically nonreactive, possibly
durability of spinal hardware is critical in spine oncology leading to less adverse effects due to in vivo implant. Ha
37
as fusion failures are notoriously high in incidence et al. also showed that there is a possibility for PEEK to be
due to poor nutrition, chemotherapy, and radiation coated with calcium phosphate by precipitation, which they
therapy. Drakhshandeh et al. proposed instrumented expected to then influence the bone-bonding properties at
spine stabilization without fusion to avoid postoperative the bone-implant interface. The materialistic properties
37
complications, citing low levels of postoperative hardware of CFR-PEEK including durability and elastic modulus, in
failure and deformity progression. Two articles reviewed combination with the high biocompatibility and possibility
29
show that in regard to mechanical durability and ability for better bone formation, make it one of the ideal candidates
to promote fusion, CFR-PEEK is comparable to titanium.
Cofano et al. described no significant difference in fusion for any orthopedic implants.
rates between titanium and CFR-PEEK. In addition, CFR-PEEK has shown utility in other spine oncology
5
Boriani et al. described no significant difference in applications, such as corpectomy cages, as well as in other
mechanical performance between CFR-PEEK hardware subspecialties that surgically treat cancer patients. 18,19
and titanium. Other work used CFR-PEEK implant cages Multiple studies have presented the efficacy of using CFR-
15

Volume 2 Issue 2 (2024) 9 doi: 10.36922/arnm.3130