What is the role of ultrasound in fracture management?: Diagnosis and therapeutic potential for fractures, delayed unions, and fracture-related infection

Callus formation and bone remodeling in a tibial nonunion after minimal invasive percutaneous screw fixation followed by extracorporeal shockwave therapy 17-months after initial trauma - A case report

INTRODUCTION

The treatment of tibial nonunion is challenging and treatment may be conservative or surgical. Conservative strategies include functional braces and weight bearing, or focused extracorporeal shockwave therapy (fESWT).

CASE DESCRIPTION

A 45-year-old male patient sustained spiral tibial shaft fractures and was treated surgically within 24 hours after the initial accident with intramedullary nails. The tibial fracture was later classified as nonunion after 11 months. Radiologic evaluation 17 months after the initial trauma demonstrated clinical nonunion, and subsequently the patient was offered a conservative approach with fESWT to facilitate an increase in callus formation. The handpiece was fitted with a stand-off II (long), penetration depth of 15 mm. Three cycles were administered in month 17, 19 and 20 after baseline. Each cycle consisted of three treatments sessions spaced with 6-8 days apart, and consisted of 3000 to 4000 impulses each given at 0.25-0.84 mJ/mm2. The number of impulses and the power at the focus point varied according to the pain response.

OUTCOMES

The patient achieved union 23 months after fracture. A clinical important improvement was observed with both Lower Extremity Functional Scale (LEFS) (18-point difference) and Patient Specific Functional Scale (PSFS) (average: 4.7 points,) The "worst pain last 24 hours" was reduced by 5 points. These values express minimal clinically important difference (MCID) values in these functional patient-reported outcome measures.

CONCLUSION

This treatment strategy may be viable in a broader setting, including private practice physiotherapy thereby treating the patient in close proximity to the patient's everyday life.

Ultrasound assessment of humeral shaft nonunion risk: a feasibility and proof of concept study

PURPOSE

To determine the feasibility and reliability of ultrasound in the assessment of humeral shaft fracture healing and estimate the accuracy of 6wk ultrasound in predicting nonunion.

METHODS

Twelve adults with a non-operatively managed humeral shaft fracture were prospectively recruited and underwent ultrasound scanning at 6wks and 12wks post-injury. Seven blinded observers evaluated sonographic callus appearance to determine intra- and inter-observer reliability. Nonunion prediction accuracy was estimated by comparing images for patients that united (n = 10/12) with those that developed a nonunion (n = 2/12).

RESULTS

The mean scan duration was 8 min (5-12) and all patients tolerated the procedure. At 6wks and 12wks, sonographic callus (SC) was present in 11 patients (10 united, one nonunion) and sonographic bridging callus (SBC) in seven (all united). Ultrasound had substantial intra- (weighted kappa: 6wk 0.75; 12wk 0.75) and inter-observer reliability (intraclass correlation coefficient: 6wk 0.60; 12wk 0.76). At 6wks, the absence of SC demonstrated sensitivity 50%, specificity 100%, positive predictive value (PPV) 100% and negative predictive value (NPV) 91% in nonunion prediction (overall accuracy 92%). The absence of SBC demonstrated sensitivity 100%, specificity 70%, PPV 40% and NPV 100% in nonunion prediction (overall accuracy 75%). Of three patients at risk of nonunion (Radiographic Union Score for HUmeral fractures < 8), one had SBC on 6wk ultrasound (that subsequently united) and the others had non-bridging/absent SC (both developed nonunion).

CONCLUSIONS

Ultrasound assessment of humeral shaft fracture healing was feasible, reliable and may predict nonunion. Ultrasound could be useful in defining nonunion risk among patients with reduced radiographic callus formation.

A systematic review and meta-analysis on the diagnostic utility of ultrasound for clavicle fractures

BACKGROUND

Ultrasound's real-time, high-resolution imaging, and accessibility at the point of care make it a valuable tool for diagnosing clavicle fractures, with growing evidence supporting its diagnostic accuracy compared to other imaging modalities.

OBJECTIVE

To assess the diagnostic utility of ultrasound in detecting clavicle fractures.

METHODS

A systematic review and meta-analysis were conducted by performing a comprehensive literature search in PubMed, Scopus, Web of Science, and Embase databases up to March 10, 2023, following established guidelines. Eligible studies that reported outcomes of interest were included, relevant data elements were extracted, and data analysis was performed using STATA software version 17.0.

RESULTS

Meta-analysis of seven included studies showed high-pooled sensitivity (0.94) and specificity (0.98) values for ultrasonography in diagnosing clavicle fractures, with low to moderate heterogeneity for sensitivity and high heterogeneity for specificity. Meta-regression and subgroup analyses revealed that pediatric studies had higher sensitivity but significantly lower specificity (P=0.01) compared to mixed or adult studies. Additional subgroup analysis in the pediatric group indicated decreased heterogeneity for specificity. Fagan plot analysis demonstrated favorable post-test probabilities for both positive and negative results across varying pre-test probabilities. Additionally, the likelihood ratio scatter matrix showed moderate to high test performance for both exclusion and confirmation purposes.

CONCLUSION

The current literature supports ultrasound as a reliable imaging modality for detecting clavicle fractures. It offers accurate diagnosis without exposing patients, especially children, to radiation.

Comparative use of ultrasound and radiography for the detection of fractures: a systematic review and narrative synthesis

Background

Traditionally, X-rays have remained the standard modality for bone fracture diagnosis. However, other diagnostic modalities most notably ultrasound have emerged as a simple, radiation-safe, effective imaging tool to diagnose bone fractures. Despite the advantages, there is a prevalent scarcity of literature recognizing its significance in bone trauma management. This review investigates the effectiveness of ultrasound in the diagnosis of various bone fractures when compared to conventional radiography such as X-rays.

Methodology

Electronic databases such as PubMed/Medline, SCOPUS, and Web of Science (WOS) were reviewed for observational studies and review articles from the years 2017-2022 utilizing MESH terminology in a broad term search strategy. The search returned a total of 248 articles. After removal of duplicates, abstract, and full-text screening this systematic review ultimately utilized data from 31 articles. All searches were performed and analyzed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) methodology and were conducted during August 2022. In accordance with the guidelines for assessing the quality of included systematic reviews, we used the AMSTAR 2020, Supplemental Digital Content 2, http://links.lww.com/MS9/A241 (A Measurement Tool to Assess Systematic Reviews) tool to evaluate the methodological quality of the included studies. A data extraction form based on the Cochrane Consumers and Communication Review group's extraction template for quality assessment and evidence synthesis was used for data extraction. The information extracted included details such as author information, database, journal details, type of study, etc. Studies included will be classified into long bones, short bones, pneumatic bones, irregular bones, ankle and knee, stress fractures, hip fractures, POCUS, and others. All included studies considered bias and ethical criteria and provided valuable evidence to answer the research question.

Results

The search returned a total of 248 articles, with 192 articles remaining after the removal of duplicates. Primary screening of the title and abstract articles from the database search and additional sources identified 68 relevant articles for full-text screening. This systematic review ultimately used data from 33 articles of the remaining articles we included all of them because they had more than 70% certainty, using the STROBE tool for observational articles, narrative reviews with the ENTREQ guide, and systematic reviews and meta-analyses with the PRISMA guide; however, two articles were excluded at the eligibility stage because of risk of bias.

Conclusion

This systematic review provides insightful evidence on safety and effectiveness of ultrasound in diagnosing fractures when compared to the conventional imaging modalities such as X-rays. This shall promote further large-scale, multi-centre research that can eventually guide clinic practice in diagnosing and managing various bone fractures.

Utility of ultrasonography in the diagnosis of lumbar spondylolysis in adolescent patients

BACKGROUND

This study aims to investigate the utility of the Doppler effect on ultrasonography for the diagnosis of very early- and early-stage lumbar spondylolysis in adolescent patients.

METHODS

In total, 76 adolescent patients with acute and subacute low back pain were prospectively enrolled, with 46 having lumbar spondylolysis and the remaining 30 having low back pain without spondylolysis. MRI and/or computed tomograms scans revealed very early- and early-stage lumbar spondylolysis. Furthermore, positive Doppler findings in ultrasonography around the area from the facet joint to the laminae were investigated.

RESULTS

There were no significant differences in age (p > 0.99) and body mass index (p = 0.11) between cases with and without spondylolysis. Very early- and early-stage spondylolysis were observed in 27.6% and 72.4% of patients, respectively. Positive power Doppler was 91.3% and 33.3% in cases with and without spondylolysis, respectively, which was significantly higher in spondylolysis (p < 0.001). The sensitivity and specificity of this positive power Doppler were 91.4% and 66.7%, respectively. Furthermore, the rate of positive power Doppler was significantly higher in early-stage spondylolysis (p = 0.02), with 75.0% and 97.6% sensitivity in very early- and early-stage spondylolysis, respectively.

CONCLUSIONS

A positive Doppler effect on ultrasonography is effective for screening very early- and early-stage spondylolysis in adolescent patients in an outpatient clinic.

Artificial Intelligence Applications in Space Medicine

INTRODUCTION:During future interplanetary space missions, a number of health conditions may arise, owing to the hostile environment of space and the myriad of stressors experienced by the crew. When managing these conditions, crews will be required to make accurate, timely clinical decisions at a high level of autonomy, as telecommunication delays and increasing distances restrict real-time support from the ground. On Earth, artificial intelligence (AI) has proven successful in healthcare, augmenting expert clinical decision-making or enhancing medical knowledge where it is lacking. Similarly, deploying AI tools in the context of a space mission could improve crew self-reliance and healthcare delivery.METHODS: We conducted a narrative review to discuss existing AI applications that could improve the prevention, recognition, evaluation, and management of the most mission-critical conditions, including psychological and mental health, acute radiation sickness, surgical emergencies, spaceflight-associated neuro-ocular syndrome, infections, and cardiovascular deconditioning.RESULTS: Some examples of the applications we identified include AI chatbots designed to prevent and mitigate psychological and mental health conditions, automated medical imaging analysis, and closed-loop systems for hemodynamic optimization. We also discuss at length gaps in current technologies, as well as the key challenges and limitations of developing and deploying AI for space medicine to inform future research and innovation. Indeed, shifts in patient cohorts, space-induced physiological changes, limited size and breadth of space biomedical datasets, and changes in disease characteristics may render the models invalid when transferred from ground settings into space.Cheung HC, De Louche C, Komorowski M. Artificial intelligence applications in space medicine. Aerosp Med Hum Perform. 2023; 94(8):610-622.

Advances in the Study of Bionic Mineralized Collagen, PLGA, Magnesium Ionomer Materials, and Their Composite Scaffolds for Bone Defect Treatment

The healing of bone defects after a fracture remains a key issue to be addressed. Globally, more than 20 million patients experience bone defects annually. Among all artificial bone repair materials that can aid healing, implantable scaffolds made from a mineralized collagen (MC) base have the strongest bionic properties. The MC/PLGA scaffold, created by adding Poly (lactic-co-glycolic acid) copolymer (PLGA) and magnesium metal to the MC substrate, plays a powerful role in promoting fracture healing because, on the one hand, it has good biocompatibility similar to that of MC; on the other hand, the addition of PLGA provides the scaffold with an interconnected porous structure, and the addition of magnesium allows the scaffold to perform anti-inflammatory, osteogenic, and angiogenic activities. Using the latest 3D printing technology for scaffold fabrication, it is possible to model the scaffold in advance according to the requirement and produce a therapeutic scaffold suitable for various bone-defect shapes with less time and effort, which can promote bone tissue healing and regeneration to the maximum extent. This study reviews the material selection and technical preparation of MC/PLGA scaffolds, and the progress of their research on bone defect treatment.

Ultrasound imaging of bone fractures

Ultrasound imaging is widely used to evaluate the neuromusculoskeletal system, and recently, a particular interest is mounting in assessing the bone tissue and fractures. Ultrasound can be considered a valuable diagnostic tool to perform a first-line evaluation of bone tissue, especially in particular settings without direct access to X-ray imaging and/or in emergency conditions. Moreover, different healing phases of bone fractures can be accurately assessed by combining the B-mode modality and (high-sensitive) color/power Doppler optimizing the management of patients-e.g., planning of progressive loads and rehabilitation procedures. In this review, we summarized the role of ultrasound imaging in the management of bone fractures and described the most common sonographic signs encountered in the daily practice by assessing different types of bone fractures and the progressive phases of the healing process.

Applications of elastography in operative neurosurgery: A systematic review

Elastography is an imaging technology capable of measuring tissue stiffness and consistency. The technology has achieved widespread use in the workup and management of diseases of the liver, breast, thyroid, and prostate. Although elastography is increasingly being applied in neurosurgery, it has not yet achieved widespread adoption and many clinicians remain unfamiliar with the technology. Therefore, we sought to summarize the range of applications and elastography modalities available for neurosurgery, report its effectiveness in comparison with conventional imaging methods, and offer recommendations. All full-text English-language manuscripts on the use of elastography for neurosurgical procedures were screened using the PubMed/MEDLINE, Embase, Cochrane Library, Scopus, and Web of Science databases. Thirty-two studies were included with 990 patients, including 21 studies on intracranial tumors, 5 on hydrocephalus, 4 on epilepsy, 1 on spinal cord compression, and 1 on adolescent scoliosis. Twenty studies used ultrasound elastography (USE) whereas 12 used magnetic resonance elastography (MRE). MRE studies were mostly used in the preoperative setting for assessment of lesion stiffness, tumor-brain adherence, diagnostic workup, and operative planning. USE studies were performed intraoperatively to guide resection of lesions, determine residual microscopic abnormalities, assess the tumor-brain interface, and study mechanical properties of tumors. Elastography can assist with resection of brain tissue, detection of microscopic lesions, and workup of hydrocephalus, among other applications under investigation. Its sensitivity often exceeds that of conventional MRI and ultrasound for identifying abnormal tissue and lesion margins.

Common Ultrasound Applications for Pediatric Musculoskeletal Conditions

PURPOSE OF REVIEW

To discuss the use of ultrasound for diagnosis and management of common pediatric musculoskeletal conditions through a case-based approach.

RECENT FINDINGS

Ultrasound is an essential diagnostic modality in the early detection of developmental dysplasia of the hips and can be used as early as 6 weeks of age when the ossific nucleus has not developed yet. Ultrasound is helpful in diagnosing traumatic injuries such as fractures and intramuscular hematomas, can visualize fracture healing at early stages, and can also be used to guide aspiration of hematomas that can help with decreasing pain and faster recovery. Ultrasound is superior to radiographs in evaluating joint effusions and soft tissue infections or masses and is better tolerated by children compared to other imaging modalities such as magnetic resonance imaging (MRI). Ultrasound is an easily accessible, affordable, non-invasive, and radiation-free imaging modality that is well tolerated by children and their families. It can aid in the diagnosis and management of a wide variety of musculoskeletal conditions including developmental, traumatic, and infectious etiologies, as well as in the evaluation of superficial soft tissue masses.

The epidemiology and direct healthcare costs of aseptic nonunions in Germany - a descriptive report

Aims

This observational cross-sectional study aimed to answer the following questions: 1) how has nonunion incidence developed from 2009 to 2019 in a nationwide cohort; 2) what is the age and sex distribution of nonunions for distinct anatomical nonunion localizations; and 3) how high were the costs for surgical nonunion treatment in a level 1 trauma centre in Germany?

Methods

Data consisting of annual International Classification of Diseases (ICD)-10 diagnosis codes from German medical institutions from 2009 to 2019, provided by the Federal Statistical Office of Germany (Destatis), were analyzed. Nonunion incidence was calculated for anatomical localization, sex, and age groups. Incidence rate ratios (IRRs) were determined and compared with a two-sample z-test. Diagnosis-related group (DRG)-reimbursement and length of hospital stay were retrospectively retrieved for each anatomical localization, considering 210 patients.

Results

In 2019, a total of 11,840 nonunion cases (17.4/100,000 inhabitants) were treated. In comparison to 2018, the incidence of nonunion increased by 3% (IRR 1.03, 95% confidence interval (CI) 0.53 to 1.99, p = 0.935). The incidence was higher for male cases (IRR female/male: 0.79, 95% CI 0.76 to 0.82, p = 0.484). Most nonunions occurred at the pelvic and hip region (3.6/100,000 inhabitants, 95% CI 3.5 to 3.8), followed by the ankle and foot as well as the hand (2.9/100,000 inhabitants each). Mean estimated DRG reimbursement for in-hospital treatment of nonunions was highest for nonunions at the pelvic and hip region (€8,319 (SD 2,410), p < 0.001).

Conclusion

Despite attempts to improve fracture treatment in recent years, nonunions remain a problem for orthopaedic and trauma surgery, with a stable incidence throughout the last decade.

Cite this article: Bone Joint Res 2022;11(8):541–547.

Effect of Silver Nanoparticles With Thermoplastic Polyurethane on Postoperative Rehabilitation of Diabetic Patients With Open Fracture of Lower Extremities

Objective

This retrospective study aims to explore the effect of silver nanoparticles with thermoplastic polyurethane (TPU/NS) on the rehabilitation of diabetic patients with open fracture of lower extremities.

Methods

Diabetic patients (n = 98) with open fracture of lower extremities treated in our hospital were analyzed retrospectively from June 2015 to December 2021. TPU/NS nanocomposites were prepared for postoperative treatment of diabetic patients with open fracture of lower extremities. First, the cultured Staphylococcus aureus and Escherichia coli were used to test the antibacterial effect of TPU/NS dressing in vitro. After using TPU/NS dressing (observation group) and traditional dressing (control group), the inflammatory reaction, clinical treatment, functional rehabilitation, and adverse reactions in patients were compared.

Results

TPU/NS dressing effectively inhibited the growth of bacteria with a minimum inhibitory concentration of 2 μg/mL. The usage of TPU/NS dressing reduced the inflammatory reaction by reducing positive rate of bacteria after the dressing on the seventh day postoperatively. Besides, the times of dressing, stopping time of wound exudation, wound healing time, length of hospital stay, and VAS score in the observation group were lower than those in the control group; the incidence of adverse reactions after treatment was lower in the observation group as compared with the control group (17.07% vs. 35.09%). Meanwhile, the functional rehabilitation and life quality of patients in the observation group were better TPU/NS dressing treatment.

Conclusion

TPU/NS dressing has the function of promoting the postoperative recovery of patients by inhibiting the bacterial infection of the wound, thus improving the limb function and life quality. As a result, there was a tremendous potential to apply the constructed TPU/NS membrane to diabetic patients with open fractures, especially those with soft tissue injury.

Contrast-Enhanced Ultrasound: A Viable Diagnostic Tool in Predicting Treatment Failure after Non-union Revision Surgery for Upper- and Lower-Limb Non-unions

Non-unions remain a major complication in the treatment of long-bone fractures and affect quality of life considerably. Both early detection and treatment of non-unions are essential to secure subsequent fracture union. Sufficient vascularization plays a key role in the healing process. The aim of this prospective study was to quantify the microperfusion within non-unions by means of contrast-enhanced ultrasound (CEUS) as early as 12 wk after non-union surgery and to examine the prognostic capability of CEUS in predicting treatment failure. Among 112 patients who had undergone non-union surgery, consolidation within 36 mo was achieved in 89 patients ("responders"), whereas 23 patients showed persistent non-unions ("non-responders") and required further surgery. CEUS quantification parameters such as peak enhancement, wash-in area under the curve and wash-in perfusion index revealed significantly higher perfusion levels in "responders" compared with "non-responders" (p < 0.05). Receiver operator characteristic curve analysis revealed that persistent fracture non-unions could be predicted with a sensitivity/specificity of 88.7%/72.2% in lower-limb non-unions and a sensitivity/specificity of 66.7%/100.0% in upper-limb non-unions. CEUS is a suitable diagnostic tool in predicting treatment failure as early as 12 wk after non-union surgery and should be integrated into the clinical routine when deciding on revision surgery at an early stage.

Fracture Nonunions and Delayed Unions Treated With Low-Intensity Pulsed Ultrasound Therapy: A Clinical Series

The incidence of nonunion of fractures has been steadily rising owing to improved life expectancy following severe injuries along with rising cases of polytrauma. Once a nonunion is established, the chances of spontaneous healing are deemed to be quite low. Fracture nonunion continues to be a challenge in clinical practice with nonunions having a considerable impact on patient’s quality of life causing both functional and psychosocial disability. Low-Intensity Pulsed Ultrasound (LIPUS) therapy is being projected as a viable and non-interventional alternative to surgical management of nonunions and delayed unions. LIPUS therapy is being widely recommended as a standalone treatment option for the treatment of established nonunions and delayed unions as it is believed to promote healing in all phases of fracture healing viz., inflammatory, intramembranous ossification, chondrogenesis, endochondral ossification and remodelling. In the current scenario of varying results and unclear clinical role of LIPUS therapy, we present a prospective case series of fracture nonunions and delayed unions treated with LIPUS therapy at a large District General Hospital. 

Percutaneous administration of allogeneic bone-forming cells for the treatment of delayed unions of fractures: a pilot study

Background

Overall, 5–10% of fractures result in delayed unions or non-unions, causing major disabilities and a huge socioeconomic burden. Since rescue surgery with autologous bone grafts can cause additional challenges, alternative treatment options have been developed to stimulate a deficient healing process. This study assessed the technical feasibility, safety and preliminary efficacy of local percutaneous implantation of allogeneic bone-forming cells in delayed unions of long bone fractures.

Methods

In this phase I/IIA open-label pilot trial, 22 adult patients with non-infected delayed unions of long bone fractures, which failed to consolidate after 3 to 7 months, received a percutaneous implantation of allogeneic bone-forming cells derived from bone marrow mesenchymal stem cells (ALLOB; Bone Therapeutics) into the fracture site (50 × 10⁶ to 100 × 10⁶ cells). Patients were monitored for adverse events and need for rescue surgery for 30 months. Fracture healing was monitored by Tomographic Union Score (TUS) and modified Radiographic Union Score. The health status was evaluated using the Global Disease Evaluation (GDE) score and pain at palpation using a visual analogue scale. The presence of reactive anti-human leukocyte antigen (HLA) antibodies was evaluated.

Results

During the 6-month follow-up, three serious treatment-emergent adverse events were reported in two patients, of which two were considered as possibly treatment-related. None of the 21 patients in the per-protocol efficacy population needed rescue surgery within 6 months, but 2/21 (9.5%) patients had rescue surgery within 30 months post-treatment. At 6 months post-treatment, an improvement of at least 2 points in TUS was reached in 76.2% of patients, the GDE score improved by a mean of 48%, and pain at palpation at the fracture site was reduced by an average of 61% compared to baseline. The proportion of blood samples containing donor-specific anti-HLA antibodies increased from 8/22 (36.4%) before treatment to 13/22 (59.1%) at 6 months post-treatment, but no treatment-mediated allogeneic immune reactions were observed.

Conclusion

This pilot study showed that the percutaneous implantation of allogeneic bone-forming cells was technically feasible and well tolerated in patients with delayed unions of long bone fractures. Preliminary efficacy evidence is supporting the further development of this treatment.

Trial registration

NCT02020590. Registered on 25 December 2013. ALLOB-DU1, A pilot Phase I/IIa, multicentre, open proof-of-concept study on the efficacy and safetyof allogeneic osteoblastic cells (ALLOB®) implantation in non-infected delayed-union fractures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13287-021-02432-4.

Ultrasound Frequency-Based Monitoring for Bone Healing

Correct assessment of the bone healing process is required for the management of limb immobilization during the treatment of bone injuries, including fractures and defects. Although the monitoring of bone healing using ultrasound poses several advantages regarding cost and ionizing radiation exposure compared with other dominant imaging methods, such as radiography and computed tomography (CT), traditional ultrasound B-mode imaging lacks reliability and objectivity. However, the body structures can be quantitatively observed by ultrasound frequency-based methods, and therefore, the disadvantages of B-mode imaging can be overcome. In this study, we created a femoral bone hole model of a rat and observed the bone healing process using the quantitative ultrasound method and micro-CT, which provides a reliable assessment of the tissue microstructure of the bone. This study analyzed the correlation between these two assessments. The results revealed that the quantitative ultrasound measurements correlated with the CT measurements for rat bone healing. This ultrasound frequency-based method could have the potential to serve as a novel modality for quantitative monitoring of bone healing with the advantages of being less invasive and easily accessible. Impact statement Bone healing monitoring with ultrasound is advantageous as it is less invasive and easily accessible; however, the traditional B-mode method lacks reliability and objectivity. This study demonstrated that the proposed ultrasound frequency-based monitoring method can quantitatively observe bone healing and strongly correlates with the computed tomography measurements for rat bone healing. This method has the potential to become a reliable modality for monitoring bone healing.

Monitoring of fracture healing. Update on current and future imaging modalities to predict union

Fracture nonunion causes considerable patient morbidity and an associated burden to society. Traditional reliance on radiographs to monitor union has limitations as bridging callus of long bone fractures can take three or more months to occur. Computed Tomographic (CT) scanning is becoming increasingly popular and can evaluate bridging callus in the late stages of healing to confirm union. The use of dynamic contrast enhanced Magnetic Resonance Imaging (MRI) and advances in nuclear imaging may yield benefits in the assessment of the infected nonunion. Emerging evidence supports the use of ultrasound to detect bridging callus prior to radiographic confirmation and it may be of use to predict patients at high risk of nonunion. This paper is part of a Supplement supported by The Osteosynthesis and Trauma Care Foundation (OTCF).

Diagnostic Accuracy of 3D Ultrasound and Artificial Intelligence for Detection of Pediatric Wrist Injuries

Wrist trauma is common in children, typically requiring radiography for diagnosis and treatment planning. However, many children do not have fractures and are unnecessarily exposed to radiation. Ultrasound performed at bedside could detect fractures prior to radiography. Modern tools including three-dimensional ultrasound (3DUS) and artificial intelligence (AI) have not yet been applied to this task. Our purpose was to assess (1) feasibility, reliability, and accuracy of 3DUS for detection of pediatric wrist fractures, and (2) accuracy of automated fracture detection via AI from 3DUS sweeps. Children presenting to an emergency department with unilateral upper extremity injury to the wrist region were scanned on both the affected and unaffected limb. Radiographs of the symptomatic limb were obtained for comparison. Ultrasound scans were read by three individuals to determine reliability. An AI network was trained and compared against the human readers. Thirty participants were enrolled, resulting in scans from fifty-five wrists. Readers had a combined sensitivity of 1.00 and specificity of 0.90 for fractures. AI interpretation was indistinguishable from human interpretation, with all fractures detected in the test set of 36 images (sensitivity = 1.0). The high sensitivity of 3D ultrasound and automated AI ultrasound interpretation suggests that ultrasound could potentially rule out fractures in the emergency department.

Antibiofilm efficacy of focused high-energy extracorporeal shockwaves and antibiotics in vitro

Aims

Biofilm formation is one of the primary reasons for the difficulty in treating implant-related infections (IRIs). Focused high-energy extracorporeal shockwave therapy (fhESWT), which is a treatment modality for fracture nonunions, has been shown to have a direct antibacterial effect on planktonic bacteria. The goal of the present study was to investigate the effect of fhESWT on Staphylococcus aureus biofilms in vitro in the presence and absence of antibiotic agents.

Methods

S. aureus biofilms were grown on titanium discs (13 mm × 4 mm) in a bioreactor for 48 hours. Shockwaves were applied with either 250, 500, or 1,000 impulses onto the discs surrounded by either phosphate-buffered saline or antibiotic (rifampin alone or in combination with nafcillin). The number of viable bacteria was determined by quantitative culture after sonication. Representative samples were taken for scanning electron microscopy.

Results

The application of fhESWT led to a ten-fold reduction in bacterial counts on the metal discs for all impulse numbers compared to the control (p < 0.001). Increasing the number of impulses did not further reduce bacterial counts in the absence of antibiotics (all p > 0.289). Antibiotics alone reduced the number of bacteria on the discs; however, the combined application of the fhESWT and antibiotic administration further reduced the bacterial count compared to the antibiotic treatment only (p = 0.032).

Conclusion

The use of fhESWT significantly reduced the colony-forming unit (CFU) count of a S. aureus biofilm in our model independently, and in combination with antibiotics. Therefore, the supplementary application of fhESWT could be a helpful tool in the treatment of IFIs in certain cases, including infected nonunions.

Cite this article: Bone Joint Res 2021;10(1):77–84.

The effects of intravenous and local tranexamic acid on bone healing: An experimental study in the rat tibia fracture model

BACKGROUND

Tranexamic acid (TXA) is an antifibrinolytic agent. It has long been used to reduce the need for perioperative blood loss in various surgeries. Few studies have investigated the effects of local and intravenous administration of TXA on fracture healing. Thus, we aimed to evaluate if TXA influences hematoma volume and fracture healing in the rat tibia fracture model.

MATERIALS AND METHODS

A tibia fracture with intramedullary Kirschner wire fixation was created in all animals. Rats were randomly divided into three groups as local TXA, intravenous TXA, and control. A dose of 50 mg/kg local and intravenous TXA was administered to the study groups. Hematoma volume was measured on the first and third days of the study. The animals were sacrificed on the 14th and 21st days for radiological and histopathological examinations.

RESULTS

There was no significant difference between the groups in terms of hematoma volume measured on Day 1 and the mean decrease of hematoma volume from Day 1 to Day 3 (p = 0.158 and p = 0.239, respectively). The total radiological scores of Day 14 and Day 21 were similar in all groups (p > 0.05 for all). There was also no significant difference between the histological staging of the fracture repair on Day 14 and Day 21 for all groups (p > 0.05 for all).

CONCLUSION

Our findings suggest that TXA's local and intravenous application makes no significant difference in fracture healing.

Ultrasound and bone: a pictorial review

The assessment of bone mainly relies on standard radiographs, CT, MRI, and bone scintigraphy depending on the anatomic region complexity and clinical scenario. Ultrasound (US), due to different acoustic impedance between soft tissues and the bone cortex, only allows the evaluation of the bone surfaces. Nevertheless, US can be useful in the evaluation of several bone disorders affecting the limbs as a result of its tomographic capabilities and high definition. This pictorial review article summarises our clinical experience in adults and reviews the literature on US bone examination. We first present the US appearance of normal bone and the main congenital anatomic variations, after which we illustrate the US findings of a variety of bone disorders. Although US has limits in bone assessment, its analysis must be a part of every musculoskeletal US examination.

Low sensitivity of histopathological examination of peri-implant tissue samples in diagnosing postoperative spinal implant infection

AIMS

To evaluate the histopathological examination of peri-implant tissue samples as a technique in the diagnosis of postoperative spinal implant infection (PSII).

METHODS

This was a retrospective analysis. Patients who underwent revision spinal surgery at our institution were recruited for this study. PSII was diagnosed by clinical signs, histopathology, and microbiological examination of intraoperatively collected samples. Histopathology was defined as the gold standard. The sensitivity for histopathology was calculated. A total of 47 patients with PSII and at least one microbiological and histopathological sample were included in the study.

RESULTS

PSII occurred in approximately 28% of the study population. Histopathology showed a sensitivity of 51.1% in the diagnosis of PSII. The most commonly found pathogens were Cutibacterium acnes and gram-positive staphylococci.

CONCLUSION

Histopathology has low sensitivity for detecting PSII. In particular, infections caused by low-virulence microorganisms are insufficiently detected by histopathology. Cite this article: Bone Joint J 2020;102-B(7):899-903.

Imaging Modalities to Assess Fracture Healing

PURPOSE OF REVIEW

This review discusses imaging modalities for fracture repair assessment, with an emphasis on pragmatic clinical and translational use, best practices for implementation, and challenges and opportunities for continuing research.

RECENT FINDINGS

Semiquantitative radiographic union scoring remains the clinical gold standard, but has questionable reliability as a surrogate indicator of structural bone healing, particularly in early-stage, complex, or compromised healing scenarios. Alternatively, computed tomography (CT) scanning enables quantitative assessment of callus morphometry and mechanics through the use of patient-specific finite-element models. Dual-energy X-ray absorptiometry (DXA) scanning and radiostereometric analysis (RSA) are also quantitative, but technically challenging. Nonionizing magnetic resonance (MR) and ultrasound imaging are of high interest, but require development to enable quantification of 3D mineralized structures. Emerging image-based methods for quantitative assessment of bone healing may transform clinical research design by displacing binary outcomes classification (union/nonunion) and ultimately enhance clinical care by enabling early nonunion detection.

Effect of therapeutic ultrasound on the quadriceps muscle injury in rats - evaluation of oxidative stress and inflammatory process

Muscle injuries are frequent, both in sports and work, and may be caused by stretching, distension, repetitive effort or bruising. Such lesions can lead to the generation of free radicals, triggering oxidative stress and the release of some inflammatory mediators. Therapeutic ultrasound (UST) is one of the most used electrotherapy resources in the physiotherapist's clinical practice. Our aim was to evaluate the use of therapeutic ultrasound on oxidative stress and inflammatory process in an experimental model of single quadriceps muscle injury in Wistar rats. We used a total of 28 male rats, weighing between 250-300 grams, randomly divided into four groups. In the right quadriceps, a simple impact of contusion was induced by means of a press. The animals were submitted to a daily UST treatment for a total of seven consecutive applications for three minutes each, that started 24 hours after the trauma induction. The results in the Trauma + Therapeutic ultrasound group at TBARS levels and in the enzymatic activity of SOD and GPx presented a significant difference. In the histological analysis of the Trauma + Therapeutic ultrasound group presented a reorganization of the fiber's structure and a reduction of the presence of inflammatory infiltrate. In the results of the immunohistochemistry of iNOS, TNF-α and NF-κB in muscle tissue, we observed that the group treated with ultrasound showed a reduction in the expression of the proteins. The use of UST was effective in protecting muscle tissue from oxidative stress, inflammatory process and in the rearrangement of muscle fibers.