An electronically instrumented internal fixator for the assessment of bone healing

Kienast, B.; Kowald, Birgitt; Seide, K.; Aljudaibi, M.; Faschingbauer, M.; Juergens, Christian; Gille, Justus

doi:10.1302/2046-3758.55.2000611

Cited by 24 publications

(26 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The PU group exhibited observably different temporal DEC profiles throughout the study, and were generally characterized by a lack of temporal pattern (Figure 8). The present data agree with previous studies where it has been shown that fracture site stiffness may be indirectly quantified by monitoring fixation plate mechanics (32), and temporally repeated measurements can identify aberrant bone healing during early stages of healing (31,40,62). DEC is advantageous for this application as it does not require direct measurement of implant strain, thus obviating the need for external fracture fixation or sensor instrumentation of custom internal fixation devices which has been associated with sensor failure (40) and difficulties in interrogating sensors through overlaying soft tissue (63).…”

Section: Discussionsupporting

confidence: 92%

Diagnostic prediction of ovine fracture healing outcomes via a novel multi-location direct electromagnetic coupling antenna

Wolynski¹,

Labus²,

Easley³

et al. 2021

Ann Transl Med

View full text Add to dashboard Cite

Background: Expedient prediction of adverse bone fracture healing (delayed-or non-union) is necessary to advise secondary treatments for improving healing outcome to minimize patient suffering. Radiographic imaging, the current standard diagnostic, remains largely ineffective at predicting nonunions during the early stages of fracture healing resulting in mean nonunion diagnosis times exceeding six months. Thus, there remains a clinical deficit necessitating improved diagnostic techniques. It was hypothesized that adverse fracture healing expresses impaired biological progression at the fracture site, thus resulting in reduced temporal progression of fracture site stiffness which may be quantified prior to the appearance of radiographic indicators of fracture healing (i.e., calcified tissue).Methods: A novel multi-location direct electromagnetic coupling antenna was developed to diagnose relative changes in the stiffness of fractures treated by metallic orthopaedic hardware. The efficacy of this diagnostic was evaluated during fracture healing simulated by progressive destabilization of cadaveric ovine metatarsals treated by locking plate fixation (n=8). An ovine in vivo comparative fracture study (n=8) was then utilized to better characterize the performance of the developed diagnostic in a clinically translatable setting.In vivo measurements using the developed diagnostic were compared to weekly radiographic images and postmortem biomechanical, histological, and micro computed tomography analyses.Results: For all cadaveric samples, the novel direct electromagnetic coupling antenna displayed significant differences at the fracture site (P<0.05) when measuring a fully fractured sample versus partially intact and fully intact fracture states. In subsequent in vivo fracture models, this technology detected significant differences (P<0.001) in fractures trending towards delayed healing during the first 30 days post-fracture.Conclusions: This technology, relative to traditional X-ray imaging, exhibits potential to greatly expedite clinical diagnosis of fracture nonunion, thus warranting additional technological development.

show abstract

Section: Discussionsupporting

confidence: 92%

Diagnostic prediction of ovine fracture healing outcomes via a novel multi-location direct electromagnetic coupling antenna

Wolynski¹,

Labus²,

Easley³

et al. 2021

Ann Transl Med

View full text Add to dashboard Cite

show abstract

“…Seide et al instrumented a bone plate with a passive sensor, employed ground reaction force measurements and applied it to nonunion patients [8]. Kienast et al [9] reported further clinical data from the same system and categorized patients into different healing patterns similar to Burny et al [22]. New device proposals are constantly upcoming [27][28][29][30][31][32][33][34][35][36][37] underlining the importance of the topic.…”

Section: Discussionmentioning

confidence: 99%

Continuous Implant Load Monitoring to Assess Bone Healing Status—Evidence from Animal Testing

et al. 2022

View full text Add to dashboard Cite

Background and Objectives: Fracture healing is currently assessed through qualitative evaluation of radiographic images, which is highly subjective in nature. Radiographs can only provide snapshots in time, which are limited due to logistics and radiation exposure. We recently proposed assessing the bone healing status through continuous monitoring of the implant load, utilizing an implanted sensor system, the Fracture Monitor. The device telemetrically transmits statistically derived implant parameters via the patient’s mobile phone to assist physicians in diagnostics and treatment decision-making. This preclinical study aims to systematically investigate the device safety and performance in an animal setting. Materials and Methods: Mid-shaft tibial osteotomies of different sizes (0.6–30 mm) were created in eleven Swiss mountain sheep. The bones were stabilized with either a conventional Titanium or stainless-steel locking plate equipped with a Fracture Monitor. Data were continuously collected over the device’s lifetime. Conventional radiographs and clinical CT scans were taken longitudinally over the study period. The radiographs were systematically scored and CTs were evaluated for normalized bone volume in the defect. The animals were euthanized after 9 months. The sensor output was correlated with the radiologic parameters. Tissue samples from the device location were histologically examined. Results: The sensors functioned autonomously for 6.5–8.4 months until energy depletion. No macroscopic or microscopic adverse effects from device implantation were observed. The relative implant loads at 4 and 8 weeks post-operation correlated significantly with the radiographic scores and with the normalized bone volume metric. Conclusions: Continuous implant load monitoring appears as a relevant approach to support and objectify fracture healing assessments and carries a strong potential to enable patient-tailored rehabilitation in the future.

show abstract

“…Despite the technological advances in the induction of electromechanical stimulations, most of the reported unilateral fixators present particular mechanical designs for distraction osteogenesis applications [ 36 , 47 ]. In the same way, the telemetric internal fixation of Kienast et al [ 53 ] and the instrumented external fixators designed by Grasa et al [ 27 ] and Reifenrath et al [ 34 ] concentrated on the stabilization and in vivo assessment of bone or fracture healing. Their inability to apply distraction prevents their adaptability to a certain amount of processes, including bone lengthening, shortening, or bone transport.…”

Section: Discussionmentioning

confidence: 99%

Real-Time Wireless Platform for In Vivo Monitoring of Bone Regeneration

Blázquez-Carmona

Sánchez-Raya

Mora‐Macías

et al. 2020

Sensors

View full text Add to dashboard Cite

For the monitoring of bone regeneration processes, the instrumentation of the fixation is an increasingly common technique to indirectly measure the evolution of bone formation instead of ex vivo measurements or traditional in vivo techniques, such as X-ray or visual review. A versatile instrumented external fixator capable of adapting to multiple bone regeneration processes was designed, as well as a wireless acquisition system for the data collection. The design and implementation of the overall architecture of such a system is described in this work, including the hardware, firmware, and mechanical components. The measurements are conditioned and subsequently sent to a PC via wireless communication to be in vivo displayed and analyzed using a developed real-time monitoring application. Moreover, a model for the in vivo estimation of the bone callus stiffness from collected data was defined. This model was validated in vitro using elastic springs, reporting promising results with respect to previous equipment, with average errors and uncertainties below 6.7% and 14.04%. The devices were also validated in vivo performing a bone lengthening treatment on a sheep metatarsus. The resulting system allowed the in vivo mechanical characterization of the bone callus during experimentation, providing a low-cost, simple, and highly reliable solution.

show abstract

An electronically instrumented internal fixator for the assessment of bone healing

Cited by 24 publications

References 13 publications

Diagnostic prediction of ovine fracture healing outcomes via a novel multi-location direct electromagnetic coupling antenna

Diagnostic prediction of ovine fracture healing outcomes via a novel multi-location direct electromagnetic coupling antenna

Continuous Implant Load Monitoring to Assess Bone Healing Status—Evidence from Animal Testing

Real-Time Wireless Platform for In Vivo Monitoring of Bone Regeneration

Contact Info

Product

Resources

About