For cell-based study, the presence of cytokines was noted as comparable, increased, or slightly increased compared to macrophages of the M0 phenotype.
The levels of inflammatory cytokines interleukin-1 beta (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor alpha (TNF-α) were quantified in muscle tissue directly anterior to the index level based on the intensity of fluorescence in each slide. The large animal model included two instrumented levels with one level implanted with a PEEK interbody cervical cage and the alternate level implanted with a PEEK zeolite composite interbody device. In vitro cell culture study in combination with a large animal functional cervical spine model. Similarly, the immune response measured at the local sites in a large animal study was also studied in order to determine the inflammatory response at the local implanted site. The objective of this study was to compare the activation state of macrophages, as determined by selected gene and protein expression profiles, following in vitro exposure to PEEK zeolite and PEEK based spinal interbody devices. It was hypothesized that IL-1β, IL-6, and TNF-α cytokine expression levels results would be different for PEEK and a novel zeolite filled PEEK composite (ZFuze, DiFusion Technologies). The combination of results from three separate kinds of studies would potentially weave a better understanding of PEEK fibrous encapsulation around retrieved implanted PEEK devices. The cell studies in combination with larger animal studies help understand the importance of appropriate choice in materials. Studies involving macrophages facilitate the understanding behind the mechanism of fibrous capsule formation anecdotally reported with PEEK implants. Based on the current understanding of the immune system, both the innate and adaptive components, a combination of tests on current design materials in spinal implant devices may help understand potential clinical complications and thus reduce the potential adverse events associated with specific design materials. In lumbar scoliosis specimens, the rigidness of spines was higher in males than in females and more pronounced in right than in left scoliosis, but only in males.īiomechanics degenerative scoliosis development initial scoliosis nature occurrence.Osteoimmunology, the study of the relationship between the musculoskeletal system and immune system, has emerged as an important consideration in biomaterial research. NZR AT was significantly lower in female DS specimens ( P=0.031) and significantly higher in female PS specimens ( P=0.031) compared to that in male specimens. NZ AT, NZ FE and NZ LB values were significantly higher in PS and NS female specimens. With the exception of ROM AT in DS specimens, ROM AT, ROM FE and ROM LB values were significantly higher in females than those in males for the DS, PS and NS specimens.
Only in males were ROM AT ( P=0.001), NZ AT ( P<0.001), NZ FE ( P=0.045), NZ LB ( P=0.002) as well as NZR AT ( P<0.001) and NZR LB ( P=0.001) values significantly lower in right compared to left scoliosis. There was no significant difference regarding the severity of DS between male and female specimens. Spine data were collected for flexion/extension (FE), lateral bending (LB), axial torsion (AT), range of motion (ROM), neutral zone (NZ) and the neutral zone ratio (NZR). We aimed to identify gender differences of mechanical factors involved in adult degenerative scoliosis (DS).Ģ0 male (60.35☖.77 years) and 19 female (58.89☙.15 years) specimens of cadaveric lumbar spines were divided into 3 groups comprised of a Cobb angle >10° (DS), a Cobb angle 3° (pre-degenerative scoliosis (PS)) and intervertebral disc angles <3° in which the Cobb angle could not be measured (non-degenerative scoliosis (NS)), respectively. The incidence of adolescent idiopathic scoliosis is higher in girls, but spine deformities are more severe in boys.