Orthopedic Publications
Journal: Journal of Orthopaedic Trauma
Publication Date: July 2024
A Novel Bone-Screw-Fastener Demonstrates Greater Maximum Compression Force Before Failure Compared with a Traditional Buttress Screw
Thorne, Tyler MD; Featherall, Joseph MD; O'Neill, Dillon MD; Lisitano, Leonard MD; Haller, Justin MD
Objective
This study compared the maximal compression force before thread stripping of the novel bone-screw-fastener (BSF) with the traditional buttress screw (TBS) in synthetic osteoporotic and cadaveric bone models.
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Conclusion
The novel bone-screw-fastener generated 11%–65% greater maximal compression force than the TBS in synthetic osteoporotic and cadaveric metaphyseal bone models. A greater compression force may increase construct stability, facilitate early weight-bearing, and reduce construct failure.
Journal: Orthopedics
Publication Date: September 6, 2023
Patient-Reported Outcomes and Computed Tomography Review After Minimally Invasive Fusion of the Sacroiliac Joint With Aggressive Joint Decortication and Joint Compression
William W. Cross III, MD; Marko N. Tomov, MD; Michelle Y. Hung, PA-C, MS; Jeffrey M. Muir, MSc, DC, MSc (Clin Epi)
Objective
The sacroiliac joint (SIJ) is a common, underrecognized source of low back pain. This study evaluated outcomes in patients undergoing sacroiliac joint fusion (SIJF) using a novel, minimally invasive SIJF system emphasizing compressive forces across an aggressively debrided SIJ. In this study, data was reviewed from a continuous set of patients presenting to a large, tertiary care hospital from September 2017 to August 2019.
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Conclusion
The benefits of this approach are evident in our rates of radiographic fusion, with independent radiographic review revealing at least partial signs of radiographic fusion in 98% of joints and definitive bone bridging (grade 3 fusion) in 81% of joints at 12-month follow-up. Our study demonstrated that a SJIF system based on the principles of joint fusion - aggressive decortication, autogenous bone grafting, and joint compression - was associated with early and durable improvements in both radiographic fusion and patient-related outcomes. The results of this study support the growing body of evidence that SIJF surgery benefits patients with SIJ dysfunction.
Journal: International Journal of Spine Surgery
Publication Date: February 8, 2023
Patient-Reported and Radiographic Outcomes After Revision Sacroiliac Joint Fusion
Jeremy C. Thompson, MD; Erick Marigi, MD; and William W. Cross, III, MD
Objective
Sacroiliac joint fusion (SIJF) has been established as an effective treatment for sacroiliac joint dysfunction. However, failure necessitating revision has been reported in up to 30% of cases. The most common indications for revision SIJF are symptomatic pseudarthrosis and implant loosening. Little is known regarding outcomes of revision SIJF. This study (the largest series of revision SIJF to date) retrospectively reviewed all revision SIJF at a single academic center between 2017 and 2020. Revision surgery was performed using the principles of joint decortication, bone grafting, compression, and rigid internal fixation.
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Conclusion
Utilizing a principles-based technique of joint decortication, compression, and rigid internal fixation, revision SIJF showed an improvement in patient-reported outcomes as well as high rate of fusion at 12 months. In regard to Patient-Reported Outcomes, ODI and NPRS scores demonstrated significant statistical and clinical improvements at all postoperative timepoints. Postoperative Radiographic Outcomes, utilizing CT images at 12 months, reflected no signs of radiographic lucencies, implant subsidences, or implant fractures and an 88.9% fusion rate with definitive bridging bone across the SIJ.
Journal: Long-Term Effects of Medical Implants
Publication Date: 2022
Can Partially Threaded Cannulated Screws Be Better Designed to Maximize Purchase in the Sacrum?
Shawn Boomsma, Ishaq Ibrahim, Nishant Suneja, Arvind G. von Keudell, & Michael J. Weaver
Objective
Current partially threaded screws have standardized thread lengths involving a small portion of the screw regardless of its overall length. The purpose of this study was to perform an imaging-based anatomic evaluation of the posterior pelvic ring to determine if the distance between the lateral cortex of the ilium and medial aspect of the SI joint (lateral sacral cortex) is a consistent value that may afford an anatomic basis upon which novel sacroiliac screws may be developed. We hypothesized that this distance would be consistent within the study population and follow a normal (Gaussian) distribution.
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Conclusion
This is the first study to define the distance from the lateral ilium to the lateral sacrum and examine its application in optimizing treatment of posterior pelvic trauma. We showed the distance from the lateral ilium to lateral sacrum is consistent and this information can be used to create improved partially threaded screws to optimize purchase within the sacrum during the surgical fixation of posterior pelvic ring injuries.
Journal: The Iowa Orthopedic Journal
Publication Date: June 2022
Does Irrigating While Drilling Decrease Bone Damage?
Justin C. Woods, MD; James L. Cook, DVM, PhD; Chantelle C. Bozynski, DVM, MS; Jason D. Tegethoff, BA; Keiichi Kuroki, DVM, PhD; Brett D. Crist, MD
Objective
Previous reports examining the effects of drilling on bone have focused primarily on cadaveric and tissue explant models, which do not account for the influences of live cells and blood supply on resultant damage. Therefore, the purpose of the present study was to evaluate the effects of saline irrigation on regulating temperature increase and acute bone damage using different drill bits and Kirschner wire devices commonly used in fracture surgery in a live translational model.
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Conclusion
Based on flute design, Osteocentric drill bits (ODB) were advanced with relatively less pressure during drilling. Per the manufacturer, OsteoGuard drill bits (Osteocentric Technologies, Inc.) are designed with a unique cutting tip, longer flutes with uniform volume, and no side cutting to remove less bone more efficiently with less damage. ODB+ had a significantly lower histopathologic score than other groups. (both DDB-, DDB+, DKW-, and SDB- (P < 0.05) (Table 1)). There were no other statistically significant findings. In contrast, the Osteocentric drill bits (ODB) performed the best in terms of limiting bony damage, drill site debris, and osteonecrosis as seen on H&E and SEM.
Journal: Injury
Publication Date: October 18, 2019
Biomechanical comparison of bone-screw-fasteners versus traditional locked screws in plating female geriatric bone
Malcolm R DeBaun , Steven T Swinford, Michael J Chen, Timothy Thio, Anthony A Behn, Justin F Lucas, Julius A Bishop, Michael J Gardner
Objectives
To biomechanically compare plated constructs using nonlocking bone-screw-fasteners with interlocking threads verses locking screws with traditional buttress threads in geriatric female bone.
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Conclusions
In female geriatric bone, constructs fixed with bone-screw-fasteners incorporate multiplanar interlocking thread geometry and performed similarly to traditional locked plating.
Journal: Journal of Orthopedic Trauma
Publication Date: April 2019
A New Fastener With Improved Bone-To-Implant Interface Shows Superior Torque Stripping Resistance Compared With the Standard Buttress Screw
Nicholas A Alfonso, Todd Baldini, Philip F Stahel
Objective
The conventional AO buttress screw used for fracture fixation relies on a historic buttress thread design, which is prone to stripping at the bone–implant interface. We hypothesized that a new Bone-Screw-Fastener with an innovative interlocking thread design demonstrates increased resistance to torque stripping forces compared with the buttress screw, without compromising pullout strength.
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Conclusions
These data demonstrate the superiority of the new Bone-Screw-Fastener over the conventional AO buttress screw regarding protection from torque stripping forces. In addition, the new thread design that interlocks to the bone does not sacrifice axial pullout resistance conveyed by the buttress screw. Future controlled trials will have to validate the in vivo relevance of these findings in a clinical setting.
Journal: Injury
Publication Date: January 2019
Ideal Length of Thread Forms for Screws Used in Screw Fixation of Nondisplaced Femoral Neck Fractures
Christina Liu, Arvind Von Keudell, Michael McTaguec, Edward K. Rodrigueza, Michael J. Weaver
Objective
The purpose of this study is to determine the thread length that will maximize purchase within the femoral head while minimizing risk of crossing the fracture line. Additional analysis was conducted to identify factors associated with the maximal possible length of treads in minimally and non-displaced femoral neck fractures.
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Conclusion
It appears that the current thread-length options available are not ideal for the fixation of minimally displaced and minimally angulated femoral neck fractures. Given the common occurrence of these injuries, fracture implants should be designed to optimize purchase within the bone while maintaining the lag screw function of the implants. The addition of a 26 mm thread length screw would substantially increase the surface area of the treads making contact within the cancellous bone of the femoral head without crossing the fracture line in the vast majority of patients.
Journal: International Journal of Spine Surgery
Publication Date: October 15, 2018
In Vitro Biomechanical Evaluation of a Novel, Minimally Invasive, Sacroiliac Joint Fixation Device
William W. Cross III, MD, Sigurd H. Bergen, MD, Nick Slater, MS, Jennifer N. Lehrman, MS, Anna G. U. S. Newcomb, MS, and Brian P. Kelly, PHD
Objectives
Sacroiliac (SI) joint pathology may result in low-back pain, which causes substantial disability. Treatment failure with operative management of SI pain may be related to incomplete fusion of the joint and to fixation failure. The objective of this study was to evaluate the initial biomechanical stability of SI joint fixation with a novel implantable device in an in vitro human cadaveric model.
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Conclusions
Instrumentation with the SI screw fixation device significantly reduced mean joint ROM compared to the destabilized condition, with similar ROM in flexion-extension and axial rotation, and it significantly reduced ROM in lateral bending compared to that for the intact joint. The ROM values observed with the instrumented condition were comparable to levels of mobility considered favorable for spinal fusion.
Journal: Patient Safety in Surgery
Publication Date: March 20, 2017
Introducing the "Bone-Screw-Fastener" for improved screw fixation in orthopedic surgery: A revolutionary paradigm shift?
Philip F Stahel, Nicholas A Alfonso, Corey Henderson, Todd Baldini
Objective
We hypothesize that the new Bone-Screw-Fastener overcomes the classic shortcomings of conventional orthopedic screws with buttress threads by ease of insertion, improved bone preservation, increased resistance to off-axis multidirectional loading forces and to stripping of the threads. These advanced biomechanical and biological properties can potentially mitigate the classic limitations of conventional buttress screws by providing better resistance to implant failure under physiological loads, preserving bone biology, and thus potentially improving patient outcomes in the future.
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Implications of Hypothesis
Once validated in multicenter RCTs, the new Bone-Screw-Fastener may drive a change in paradigm with regard to its innovative biomechanical principles and biologic bone preservation for surgical applications requiring screw fixation.
Veterinary Publications
Journal: Frontiers in Veterinary Science
Publication Date: June 29, 2023
Ex Vivo Biomechanical Evaluation of a Bone-Screw-Fastener for Tibial Plateau Leveling Osteotomy
William S. Kettleman, Michael H. Jaffe, Robert W. Wills, Sara J. Dietz, and Steve H. Elder
Objective
The objective of this study was to investigate the effect of a novel screw type on stiffness and failure characteristics of a tibial plateau leveling osteotomy (TPLO) construct under cyclic loading conditions. The authors hypothesized that bone-screw-fasteners (BSF) would result in superior biomechanical stability compared with locking buttress screws (LBS).
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Results
The findings of this current study suggest that stabilization of the TPLO with bone-screw-fasteners provided no advantage to biomechanical stability under cyclic axial loading conditions when compared to the locking buttress screw. Bone-screw-fasteners may be an acceptable alternative to traditional locking screws for TPLO. Further research, particularly in vivo experiments, is warranted prior to clinical application.
Internal White Papers
Biomechanical Evaluation of Standard and Novel Sacroiliac Joint Fusion Bone-Implant Interfaces in a Sawbones Model
Quinten Kunz*, Justin Hyer*, Bridger Evans**, and Andrew Fauth, PhD*
*OsteoCentric Technologies, Inc., **NexTek Innovations, inc.
Abstract
Integrity-SI® Fusion implants with standard bone-implant interfaces based on common buttress
threads and identical implants with a Mechanical Integration interface using UnifiMI were
biomechanically compared for maximum compression force, peak stripping torque, and cantilever bending/lever-out yield load in bone-foam blocks.
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Summary
Integrity-SI Fusion Fastener implants with UnifiMI demonstrated significantly higher peak compression, peak stripping torque, and cantilever bending yield loads when tested in bone-foam constructs. These results demonstrate the marked improvement in biomechanical performance and stability that Mechanical Integration can provide an existing implant when converted to UnifiMI.
