SINTX Technologies (United States)

Examines injuries in hockey as one of the most pressing issues facing modern sports medicine and epidemiology. Domestic and foreign epidemiological data are presented according to the level of sports events, gender and age of athletes, localization of injury, as well as characteristics of internal and external risk factors.

Disclosure: R.I. Gafni: Calcilytix Therapeutics. I.R. Hartley: Calcilytix Therapeutics. K.L. Roszko: Calcilytix Therapeutics. E.F. Nemeth: Calcilytix Therapeutics. K. Pozo: Calcilytix Therapeutics. R. Meadows: Calcilytix Therapeutics. E. Ferguson: Calcilytix Therapeutics. A. Mathew: Calcilytix Therapeutics. M. Roberts: Calcilytix Therapeutics. S. Adler: Calcilytix Therapeutics. M.T. Collins: Calcilytix Therapeutics.Autosomal dominant hypocalcemia type 1 (ADH1), due to activating calcium-sensing receptor gene (CASR) variants, manifests as low PTH, hypocalcemia, hypercalciuria, hyperphosphatemia and hypomagnesemia. Calcium and active vitamin D treatment worsens hypercalciuria, which may result in renal morbidity. Calcilytics are negative allosteric modulators of the calcium-sensing receptor (CaSR) that decrease the sensitivity of hyperactive receptors to extracellular calcium and normalize biochemical abnormalities in ADH1 mouse models. This Phase 2b open-label study (NCT04581629) of the oral investigational calcilytic encaleret included 2 5d inpatient periods followed by a 24W outpatient period and then a long-term extension (LTE). Conventional therapy was stopped prior to encaleret initiation. After about 18 months in Phase 2b LTE, participants continued encaleret treatment in the CALIBRATE study LTE (NCT05680818). Thirteen adults with ADH1 were enrolled and encaleret was individually titrated to normalize albumin-corrected calcium (cCa). Encaleret was well-tolerated. There were 2 unrelated serious adverse events during the LTE: chest pain and post-surgical pain. There were no treatment discontinuations or withdrawals prior to the LTE; one participant withdrew during the LTE for family planning but subsequently re-enrolled without an intervening pregnancy. Mean±SD values taken pre-dose at P3W24 and LTEM36 compared to baseline (BL) are presented. PTH levels were low at BL (6.3±7.8 pg/mL [nl 10-65]) and normal at P3W24 (35.3±10.2) and LTEM36 (23.7±16.8 [p<0.01]). Similarly, hypocalcemia at BL (cCa=7.1±0.4 mg/dL [nl 8.4-10.2]) had normalized at P3W24 (9.0±0.5) and LTEM36 (9.0±0.3 [p<0.01]). BL hypercalciuria (395±216 mg/d [nl <250-300]) normalized to 202±83 at P3W24 and LTEM36 (162±103 [p<0.01]). BL blood phosphate (4.5±1.1 mg/dL [nl 2.3-4.7]) decreased at P3W24 (3.7±0.5) and LTEM36 (3.7±0.7 [p<0.05]). Blood magnesium rose (BL 1.7±0.2 mg/dL [nl 1.6-2.6]); P3W24 2.0±0.2; LTEM36 2.0±0.2 [p<0.01]). Bone turnover markers, adjusted for age, sex, and menopausal status by dividing by the upper limit of normal for each participant [nl 0-1], were low at BL (CTX=0.4±0.3; P1NP=0.3±0.1) and increased at P3W24 (CTX=1.15±1.0; P1NP=1.22±1.05) and LTEM36 (CTX=0.71±0.53; P1NP=1.37±0.98 [p<0.05; p<0.01]). Compared with screening, DXA Z-scores had decreased at LTEM24 but stabilized at LTEM36 (AP spine Z=2.6±1.5→2.2±1.6→2.2±1.6; Total hip Z=2.2±1.4→1.8±1.1→1.7±1.1; 1/3 radius Z=0.2±0.9→ -0.2±0.4→ -0.1±0.5, n=10-11 [p<0.05]). In patients with ADH1, encaleret corrected biochemical abnormalities and increased bone turnover, with stabilization of bone density by 42 months of continuous treatment. These consistent and sustained results are clinically meaningful and support ongoing efficacy and safety evaluation of encaleret as the first potential treatment for ADH1.Presentation: Monday, July 14, 2025

Continuous carbon fiber–reinforced polyetherketoneketone (CCF-PEKK) is a thermoplastic composite with properties suitable for trauma plate applications (elastic modulus, strength, radiolucency, and inertness). However, components manufactured by fused filament fabrication (FFF) often display non-uniform (anisotropic) mechanical properties and contain microstructural voids. To address these limitations, we investigated a hybrid-manufacturing approach, combining FFF with continuous carbon fiber reinforcement followed by uniaxial compression molding. Here, we asked: 1. Can layup orientation be tuned to replicate the mechanical stiffness of cortical bone in flexion? 2.) How does the structure of the different layups influence fracture behavior? and 3.) Do silicon nitride (Si3N4) (a bioactive ceramic with antimicrobial properties) embedded particulate coatings affect flexural or fracture behavior? To answer these research questions, we fabricated CCF-PEKK plates with three fiber layups (0°/90°, +45°/−45°, and 0°/90°/+45°/−45°) with the goal of approaching the flexural modulus of cortical bone (1.7–16.3 GPa). Next, half of the hybrid-specimens were spray-coated with submicron Si3N4 powder. Four-point bending tests demonstrated that fiber orientation significantly influenced flexural modulus and strength. The 0°/90° layup exhibited the highest flexural modulus (67.6 GPa) and strength (1020 MPa), while the +45°/−45° configuration showed the lowest values (15.6 GPa, 217 MPa), but displayed superior load dissipation in axial fiber orientations and was able to reproduce moduli values akin to those of cortical bone range. SEM analysis confirmed uniform Si3N4 coating distribution, with no observable impact on crack initiation or propagation. No difference (p > 0.01) in flexural modulus or strength was observed between the uncoated and coated specimens, suggesting that Si3N4 is not associated with static flexural properties of CCF-PEKK. These findings support the feasibility of hybrid-manufactured CCF-PEKK trauma plates as potential alternatives to conventional metallic implants. Further investigations into the long-term fatigue behavior and bioactivity of Si3N4 coatings are warranted.

The spinal diseases commonly faced by people in the 19th century included intervertebral disc degeneration, tuberculosis and congenital defects that resulted in neurological impairment and global disability. To address these issues, cervical spine surgery was performed. Modern techniques currently used in spine surgery include interbody devices, pedicle screws, artificial discs and bone grafts. The postoperative complications clinically reported during follow-up include nonunion and implant subsidence, which remain significant drawbacks. The objective of this study is to develop a 3-dimensional finite element model of the C2-C7 cervical spine and validate it against existing experimental studies. The loading conditions considered for this study include a compressive preload of 50 N and a 1 Nm moment applied to the C2 vertebra, with the C7 vertebra fixed at the bottom. In this study, the biomechanical alterations of 4 different cage morphologies were analysed using finite element analysis. Valeo cages with 4 distinct designs were implanted at the C5-C6 level, and physiological motion at the surgical site was studied. Cage subsidence and migration, which can lead to adjacent segment disc degeneration, were also examined. Subsidence was primarily attributed to higher stress encountered in the cage, so stress distribution within the cages was evaluated. Additionally, stress distribution in the anterior plate and screws was analysed. The study concludes that introducing anterior plate and screw fixation helps prevent cage subsidence. Physiological motion at the surgical level was reduced compared to the intact model. Adjacent disc stress was also evaluated and found to be lower than in the intact model.

Degeneration of the lumbar spine is common in aging adults and reflects a significant morbidity burden in this population. In selected patients that prove unresponsive to non-surgical treatment, posterior lumbar fusion (PLF) surgery, with or without adjunctive transforaminal lumbar interbody fusion (TLIF) can relieve pain and improve function. We describe here the radiographic fusion rates for PLF versus TLIF, using an intervertebral spinal cage made of silicon nitride ceramic (chemical formula Si3N4). This retrospective cohort analysis enrolled 99 patients from August 2013 to January 2017; 17 had undergone PLF at 24 levels, while 82 had undergone TLIF at 104 levels. All operations were performed by a single surgeon at one institution. Radiographic and clinical outcomes were compared between PLF and TLIF at 2 and 6 weeks and then at 3, 6, 12, and 24 months. TLIF patients fused at higher rates compared to PLF at the 3-month (38.5% vs. 8.3%, P=0.006), 6-month (78.7% vs. 35.0%, P<0.001) and 12-month time periods (97.9% vs. 81.3%, P=0.018), with no difference at 24 months (100% vs. 94.4%, P=0.102). Index level segmental motion was significantly less and intervertebral disc height was improved in TLIF over PLF at all follow up intervals. Foraminal height was only greater in early follow up periods (2 weeks, 6 weeks and 3 months). TLIF patients experienced lover rates of PI-LL mismatch which was maintained across long term follow-up. Pelvic tilt was lower following TLIF compared to PLF, with no differences in complication rates between study groups. Our retrospective series demonstrated that TLIF performed with silicon nitride interbody cages led to earlier radiographic fusion, greater restoration of disc and foraminal height, increased segmental rigidity and improved sagittal alignment when compared to PLF alone.

Surface roughness, bioactivity, and antibacterial properties are desirable in skeletal implants. We hot-pressed a mix of particulate sodium chloride (NaCl) salt and silicon nitride (β-Si3N4) onto the surface of bulk PEEK. NaCl grains were removed by leaching in water, resulting in a porous PEEK surface embedded with sim15 vol% β-Si3N4 particles. This functionalized surface showed the osteogenic and antibacterial properties previously reported in bulk silicon nitride implants. Surface enhancement of PEEK with β-Si3N4 could improve the performance of spinal fusion cages, by facilitating arthrodesis and resisting bacteria.

Iliac crest autograft or allograft spacers have been traditionally utilized in anterior cervical discectomy and fusion (ACDF) to provide vertebral stabilization and enhanced osteogenesis. However, abiotic cages have largely replaced these allogenic sources due to host-site morbidities and disease transmission risks, respectively. Although devices made of polyetheretherketone (PEEK) or titanium-alloys (Ti) have gained wide popularity, they lack osteoinductive or conductive capabilities. In contrast, silicon nitride (Si3N4) is a relatively new implant material that also provides structural stability and yet purportedly offers osteopromotive and antimicrobial behavior. This study compared radiographic outcomes at ≥12 months of follow-up for osseous integration, fusion rate, time to fusion, and subsidence in ACDF patients with differing intervertebral spacers. Fifty-eight ACDF patients (108 segments) implanted with Si3N4 cages were compared to thirty-four similar ACDF patients (61 segments) implanted with fibular allograft spacers. Lateral radiographs (normal, flexion, and extension) were obtained at 3, 6, 12, and 24 months to assess osseous integration, the presence of bridging bone, the absence of peri-implant radiolucencies, subsidence, and fusion using both interspinous distance (ISD) and Cobb angle methods. In patients with ≥12 months of follow-up, fusion for the allograft spacers and Si3N4 cages was 86.84% and 96.83%, respectively (ISD method, P=0.10), and 67.65% and 84.13%, respectively (Cobb angle method P=0.07), while osseointegration was 76.32% and 93.65%, respectively (P=0.02). The time to fusion significantly favored the Si3N4 cages (4.08 vs. 8.64 months (ISD method, P=0.01), and 6.76 vs. 11.74 months (Cobb angle method, P=0.04). The assessed time for full osseointegration was 7.83 and 19.24 months for Si3N4 and allograft, respectively (P=0.00). Average subsidence at 1-year follow-up was 0.51 and 2.71 mm for the Si3N4 and allograft cohorts, respectively (P=0.00). In comparison to fibular allograft spacers, Si3N4 cages showed earlier osseointegration and fusion, higher fusion rates, and less subsidence.