The Role of Ultrasound Imaging of Callus Formation in the Treatment of Long Bone Fractures in Children

Diagnosis of suspected pediatric distal forearm fractures with point-of-care-ultrasound (POCUS) by pediatric orthopedic surgeons after minimal training

BACKGROUND

Several studies have advocated the use of ultrasound to diagnose distal forearm fractures in children. However, there is limited data on the diagnostic accuracy of ultrasound for distal forearm fractures when conducted by pediatric surgeons or trainees who manage orthopedic injuries in children. The objective of this study was to determine the diagnostic accuracy of point-of-care ultrasound (POCUS) for pediatric distal forearm fractures when conducted by pediatric surgeons and trainees after minimal training.

METHODS

This diagnostic study was conducted in a tertiary hospital emergency department in Germany. Participants were children and adolescents under 15 years of age who presented to the emergency department with an acute, suspected, isolated distal forearm fracture requiring imaging. Pediatric surgeons and trainees, after minimal training for sonographic fracture diagnosis, performed 6-view distal forearm POCUS on each participant prior to X-ray imaging. All data was retrospectively collected from the hospital's routine digital patient files. The primary outcome was the diagnostic accuracy of POCUS compared to X-ray as the reference standard.

RESULTS

From February to June 2021, 146 children under 15 met all inclusion and exclusion criteria, and 106 data sets were available for analysis. Regarding the presence of a fracture, X-ray and Wrist-POCUS showed the same result in 99.1%, with 83/106 (78.3%) fractures detected in both modalities and one suspected buckle fracture on POCUS not confirmed in the radiographs. Wrist-POCUS had a sensitivity of 100% (95% CI [0.956, 1]) and a specificity of 95.8% (95% CI [0.789, 0.999]) compared to radiographs. In 6 cases, there were minor differences regarding a concomitant ulnar buckle. The amount of prior ultrasound training had no influence on the accuracy of Wrist-POCUS for diagnosing distal forearm fractures. All fractures were reliably diagnosed even when captured POCUS images did not meet all quality criteria.

CONCLUSION

Pediatric surgeons and trainees, after minimal training in POCUS, had excellent diagnostic accuracy for distal forearm fractures in children and adolescents using POCUS compared to X-ray.

Prevention of Adhesions after Bone Fracture Using a Carboxymethylcellulose and Polyethylene Oxide Composite Gel in Dogs

The formation of adhesions is a common complication following traumatic injuries and surgical procedures, often resulting in pain, stiffness, and loss of function. This study aimed to evaluate the feasibility and safety of using a composite material comprising of carboxymethylcellulose (CMC), polyethylene oxide (PEO), and calcium chloride, for preventing adhesions between muscle and bone during the healing stage, as well as its effect on the bone healing process. Ten healthy purpose-bred laboratory Beagle dogs were randomly subjected to two consecutive operations with a 6-month interval, alternating between left and right forelimbs. On the left forelimb an osteotomy at the ulna was performed, while on the right forelimb the same procedure was supplemented by the application of the anti-adhesion agent in the osteotomy site prior to closure. Clinical, diagnostic imaging, macroscopic, and histological evaluations were performed at various time points. The results showed no significant differences in surgical site perimeter (p = 0.558), lameness (p = 0.227), and radiographic bone healing (p = 0.379) between the two groups. However, the macroscopic (p = 0.006) and histological assessments revealed significantly lower adhesion scores (p = 0.0049) and better healing (p = 0.0102) in the group that received the anti-adhesion agent. These findings suggest that the CMC/PEO composite material is a safe and potentially effective intervention for preventing post-traumatic and post-surgical adhesions in canine patients without compromising bone healing. Further research is warranted to fully characterize the clinical benefits of this approach.

Fracture sonography-review of literature and current recommendations

Over a span of more than two years, a collaborative expert group consisting of 9 professional societies has meticulously crafted the S2e guideline on fracture sonography. This publication encapsulates the essential insights pertaining to specific indications. A thorough and systematic literature search, covering the period from 2000 to March 2021, was conducted across PubMed, Google Scholar, and the Cochrane Database of Systematic Reviews, complemented by an evaluation of bibliographies. Inclusion criteria encompassed randomized controlled clinical trials, observational clinical trials, meta-analyses, and systematic reviews, while guidelines, conferences, reviews, case reports, and expert opinions were excluded. The SIGN grading system (1999-2012) was applied to assess evidence, and resultant SIGN tables were presented to the expert group. Specific recommendations for the application of fracture sonography were then derived through unanimous consensus after detailed discussions. Out of the initial pool of 520 literature sources, a meticulous screening and content assessment process yielded 182 sources (146 clinical studies and 36 meta-analyses and systematic reviews) for evaluation. The comprehensive analysis identified twenty-one indications that substantiate the judicious use of fracture sonography. Ultrasound emerges as a pragmatic and user-friendly diagnostic method, showcasing feasibility across a diverse range of indications.

Fracture sonography - Literature review and current recommendations

PURPOSE

Over the course of more than two years, an expert group of 9 professional societies has created the S2e guidelines for fracture sonography. This publication summarizes the key points regarding the individual indications.

MATERIALS AND METHODS

A systematic literature search was performed in PubMed, Google Scholar, and the Cochrane Database of Systematic Reviews from 2000 to March 2021 with evaluation of the literature lists. Randomized controlled clinical trials, observational clinical trials, meta-analyses, and systematic reviews were included. Guidelines, conferences, reviews, case reports, and expert opinions were excluded. Evidence was graded using the SIGN grading system 1999-2012, and the SIGN tables were then presented to the expert group. These were used to develop specific recommendations for the use of fracture sonography. All recommendations were discussed in detail and finally unanimously agreed upon.

RESULTS

Of the 520 primary literature sources found, 182 sources (146 clinical studies and 36 meta-analyses and systematic reviews) were evaluated after screening and content assessment. 21 indications that allow reasonable application of fracture sonography were identified.

CONCLUSION

Ultrasound is a sensible, easy-to-use diagnostic method that is feasible for a large number of indications.

Ultrasound in sports traumatology

BACKGROUND

 Ultrasound (US) has numerous applications in sports traumatology. The technical progress of mobile US devices has led to increasing use of ultrasound as a primary diagnostic tool. New applications such as elastography and 3 D vascularization are used for special indications.

METHOD

 The purpose of this review is to present the current status of ultrasound in the diagnosis of sports injuries and sport traumatology including established applications and new technical advances. US is presented both in its comparison to other imaging modalities and as a sole diagnostic tool.

RESULTS AND CONCLUSION

 US can be used for initial diagnosis to improve the clinical examination and for intensive short-term follow-up imaging. The main areas of application are currently the diagnosis of acute muscle and tendon injuries as well as overuse injuries. In particular, the exclusion of structural muscle injuries can be adequately ensured with US in the majority of anatomical regions. The recently published guideline on fracture ultrasound has strengthened the clinical evidence in this area, especially in comparison to conventional radiography and in the development of algorithms and standards. The increasing use of mobile ultrasound equipment with adequate image quality makes US a location-independent modality that can also be used at training sites or during road games.

KEY POINTS

  · Typically used for quick, focused initial diagnostic assessment and short-term follow-up after injury. · Mobile US devices allow increased use in training centers and training camps. · New US applications (SWE, 3 D) increase standardization in follow-up of tendon injuries. · Targeted use of US for musculoskeletal diagnostic assessment saves money and frees up capacity.

CITATION FORMAT

· Lerchbaumer MH, Perschk M, Gwinner C. Ultrasound in sports traumatology. Fortschr Röntgenstr 2024; 196: 440 - 449.

In vivo evaluation of a polyester and fiberglass composite intramedullary nail for femoral osteosynthesis in calves

The objective of this study was to test a composite of polyester resin and fiberglass in the form of an intramedullary nail for osteosynthesis of femoral fractures in calves. The methodology was established based on a previous study that used a bovine femur finite element model to simulate fractures, which were then stabilized by the same nails as proposed in this study. General anesthesia was induced in six calves followed by fracture creation via an oblique incision in the middle third of the femoral diaphysis, and osteosynthesis was immediately performed by retrograde insertion of the composite nail. Locking was achieved by drilling the bone and nail without using a jig and introducing two stainless steel screws proximal and two distal to the fracture line. Five of the six calves achieved complete fracture healing after 60 days. No signs of incompatibility or toxicity of the composite were observed. However, limitations were observed during the surgery, such as difficulty in drilling the nail and trimming the remainder portion of the nail that extended beyond the length of the bone. Small fragments produced by these maneuvers were considered irritating to soft tissues during the postoperative period. It was also found that small cracks in the nail tended to propagate in the form of longitudinal fractures. In conclusion, an intramedullary nail made of polyester resin and fiberglass (a low-cost and easy-to-acquire material) was considered biocompatible and capable of allowing bone healing of femoral fractures in young cattle. However, the development of solutions for the reported limitations is crucial prior to recommending the proposed composite for clinical use.

The value of ultrasonography in predicting the outcomes of simple long bone fractures treated by closed intramedullary nail fixation

PURPOSE

Ultrasonography has been used increasingly in orthopaedic practice credited to its low cost, easy accessibility, non-invasiveness, reproducibility, and safety from radiation. The purpose of this study was to test the validity and efficacy of ultrasonography as an adjunct in the assessment of fracture healing in long bones treated with intramedullary interlocking devices and its predictive value in determining the need for a secondary surgical procedure.

METHODS

This was a descriptive longitudinal study of 40 skeletally mature patients who sustained long bone fractures of the tibia or femur treated using intramedullary interlocking nails. Patients with comminuted and segmental fracture patterns were excluded from the study. Each patient was evaluated at 6- and 12-week post-surgery using standard orthogonal radiographs and ultrasonography to assess fracture healing. Patients were then followed up until fracture union. Quantitative data was analyzed using frequency statistics and descriptive data with inferential statistics.

RESULTS

Ultrasonography predicted 87.5% union and 12.5% delayed or non-union as early as 6 weeks after surgery, while radiographs predicted 22.5% union as late as 3 months of follow-up. The sensitivity and specificity of ultrasonography in assessing fracture healing were 100% and 97.2%, respectively, with a positive predictive value of 80.0%. Vascular resistance index was less than 0.5 in all patients who developed delayed or non-union.

CONCLUSION

Ultrasonography is able to predict fracture outcomes much earlier than standardized radiographs with comparable sensitivity and specificity. Vascular resistance index is an objective parameter in assessing callus quality and predicting fracture outcomes.

The Use of Stromal Vascular Fraction in Long Bone Defect Healing in Sheep

The objectives of the present study were to evaluate (a) the feasibility of using stromal vascular fraction (SVF) and nanocrystalline hydroxyapatite (nHA) paste in combination for the treatment of segmental bone defect, (b) the quality of the callus produced, (c) the potential improvement of the autograft technique, and (d) the direct comparison of the biomaterial to the use of autogenous cancellous bone. Unilateral, segmental mid-diaphyseal bone defect was created on the right metatarsus of skeletally mature sheep animals (n = 24) under anesthesia (D0). Residual segments were stabilized by stainless-steel plates and appropriate screws. Defects were managed as follows: group A: use of nHA paste to filling, group B: use of autogenous bone graft mixed with nHA bone paste, placed in defect, group C: use of SVF mixed with nHA bone paste injected into defect, group D: use of bone graft and SVF with nHA paste before apposition in bone defect. SVF had been previously isolated from adipose tissue of the animals intra-operatively after digestion with collagenase solution and neutralization. Animals were evaluated clinically and by X-raying and ultrasonographic examination of the defect, at regular intervals, until D90. Ultrasonographic assessment performed along the length of the defect included calculation of the length of the bone defect and assessment of vascularization. SVF was successfully isolated from group C and D animals, with the average yield being 1.77 × 106 cells. The comparison of clinical scores (based on the 'Kaler scale') on each post-operative day indicated significant differences between the four groups on D1 to D30 (p < 0.01); the median clinical score within group A was 2.5 for D1-D30 and 1 for the entire period; respective scores for other groups were 1.5 (p = 0.07) and 0 (p = 0.033). Differences in radiographic assessment scores were significant for scores obtained on D60 (p = 0.049) and D90 (p = 0.006). There was a significant difference between the four groups in the length of the bone defect, as assessed ultrasonographically, for the entire length of the study; median values were 8, 8.5, 6, and 8 mm for groups A, B, C, and D, respectively (p = 0.008). There was a significance in the differences between median scores obtained during the histopathological examination: 2, 11, 13.5, and 12 for group A, B, C, and D (p = 0.022). There was an inverse correlation between the overall scores of histopathological evaluations and the length of the bone defect (observed on D90) (p < 0.0001) and a correlation between the overall scores and the radiographic assessment scores (obtained on D90) (p < 0.0001). This is the first study in which the efficacy of fresh autologous Stromal Vascular Fraction (SVF) from adipose tissue in enhancing bone healing in a long, weight-bearing, diaphyseal bone was evaluated. It is concluded that the lumbosacral region was an attractive site for harvesting adipose tissue, the use of SVF contributed to faster rehabilitation post-operatively, and SVF significantly enhanced bone formation; in general, the results indicated an osteogenic potential of SVF comparable to the gold standard autologous bone graft.

Sonographic Fracture Diagnosis in Children and Adolescents

BACKGROUND

Clinical examination after trauma, especially in young children, often proves difficult. As a result, the majority of images show unremarkable findings in the imaging workup of trauma by radiography. Sonography represents an imaging technique without the use of X-rays. As the quality of ultrasound equipment has increased over the past 20 years, numerous studies have demonstrated that fractures in children and adolescents can be detected with very high sensitivity and specificity by sonography.

METHOD

This paper reviews the results obtained so far in the literature. Based on these findings, the importance of sonographic fracture diagnosis in childhood and adolescence for the most important locations is demonstrated.

RESULTS

When examining with a high-frequency linear transducer, sensitivities and specificities of more than 90 % can be achieved for the detection of fractures. Dislocations are also reliably detected. In contrast to X-ray examination, sonography allows the diagnosis of cartilage and soft-tissue injuries. Sonography reveals callus formation earlier than radiographs. The examination causes less pain than X-ray examination. If sonographic clarification is limited purely to fracture detection or exclusion, less time is required compared to X-ray diagnosis. The procedure can be learned quickly. If the documentation follows a defined standard examination procedure, the results can also be reproduced by non-examiners.

CONCLUSION

So far, sonography has only been an additive procedure in fracture diagnosis. However, there are now initial recommendations for sonographic fracture diagnosis alone, such as in skull, clavicle and non-displaced distal forearm fractures.

KEY POINTS

· Sonography can be used to detect or rule out fractures very sensitively.. · Sonographic examination causes less pain than X-ray examination.. · Sonography is usually an additive procedure in fracture diagnosis.. · In the meantime, sonography alone may be sufficient for diagnosing individual fractures..

ZITIERWEISE

· Moritz JD. Sonografische Frakturdiagnostik im Kindes- und Jugendalter. Fortschr Röntgenstr 2023; 195: 790 - 796.

Effect of amniotic membrane and platelet-rich fibrin membrane on bone healing post endodontic surgery: An ultrasonographic, randomized controlled study

The use of membrane barriers and bone grafting materials in endodontic surgery promotes healing by regeneration rather than repair by scar tissue. Due to its valuable regenerative and therapeutic properties, the human amniotic membrane can support ideal periapical rehabilitation and promote better healing after surgery. The current trial aimed to evaluate the amniotic membrane's healing potential and compare it with platelet-rich fibrin using color doppler sonography. The current study is a randomized, double-blinded, parallel-group, single-center study. Thirty-four systematically healthy individuals requiring endodontic surgery who fulfilled all inclusion and exclusion criteria were selected and randomly placed in two groups. Surgical curettage of the bony lesion was performed and filled with hydroxyapatite graft. Amniotic membrane (Group 1) and platelet-rich fibrin (Group 2) were placed over the bony crypt, and the flap was sutured back. The lesion's surface area and vascularity were the parameters assessed with ultrasound and color doppler. and observations: The groups found a significant difference in mean vascularity at 1 month and mean vascularity change from baseline to 1 month (p < 0.05). Mean surface area had no statistically significant difference between the groups. However, in terms of the percentage change in surface area, a significant difference was found from baseline to 6 months (p < 0.05). Amniotic membrane was a significantly better promoter of angiogenesis than platelet-rich fibrin in the current trial. The osteogenic potential of both materials was similar. However, the clinical application, availability, and cost-effectiveness of amniotic membrane support it as a promising therapeutic alternative in clinical translation. Further large-scale trials and histologic studies are warranted.

Monitoring the Progress of Treatment in Fracture Non-Union: The Role of Alkaline Phosphatase and Ultrasonography

Objective  To evaluate the role of serum alkaline phosphatase (ALP) and ultrasonography (USG) in monitoring the progress of treatment in diaphyseal non-unions. Methods  This prospective observational cohort study included adult patients with diaphyseal fractures of major long bones previously treated with internal fixation and eventually resulting in non-union. Following the definitive treatment for non-union, the patients were followed-up periodically for six months, and serial monitoring of the levels of ALP and USG were performed along with radiographs (X-rays) to ascertain the status of the union. Results  After an initial rise at seven weeks, ALP levels declined to normal values in fractures which united, whereas they remained high in cases of persistent non-union. Similarly, after an elevation of the vascular resistive index (RI) at around 12 weeks in all the patients, it decreased in cases progressing to union, while it remained persistently high even at 24 weeks in fractures failing to unite. Cases of persistent non-union continued to show hypoechogenic callus at 24 weeks instead of converting into hyperechogenic callus, as observed in cases which progressed to union. Conclusion  Significant changes suggestive of union appeared simultaneously on the X-rays, USG and ALP levels during the follow-up. However, a serial examination of the ALP levels and USG during the follow-up gave a hint of the direction of progress in the healing process of fracture non-union. Their role in monitoring the outcome of non-union is more complimentary than supplementary to the X-rays.

Problem Solved: Integral Applications of Musculoskeletal Ultrasound

Musculoskeletal ultrasound has grown substantially in use over the past several years as an indispensable companion to magnetic resonance imaging and other imaging modalities. This article reviews 10 integral applications of musculoskeletal ultrasound as a problem-solving tool with correlative case examples. These applications include the following: (1) accessibility and portability, (2) targeted imaging, (3) dynamic imaging, (4) contralateral comparison, (5) Doppler imaging, (6) increased spatial resolution, (7) solid versus cystic comparison, (8) posttraumatic imaging, (9) postsurgical imaging, and (10) treatment delivery and optimization. The review will help the radiologist recognize the complementary uses of musculoskeletal ultrasound with radiography, computed tomography, and magnetic resonance imaging.

Assessment of fracture healing in orthopaedic trauma

Fracture healing is a complex physiologic process, relying on the crucial interplay between biological and mechanical factors. It is generally assessed using imaging modalities, including conventional radiology, CT, MRI and ultrasound (US), based on the fracture and patient features. Although these techniques are routinely used in orthopaedic clinical practice, unfortunately, they do not provide any information about the biomechanical status of the fracture site. Therefore, in recent years, several non-invasive techniques have been proposed to assess bone healing using ultrasonic wave propagation, changes in electrical properties of bones and callus stiffness measurement. Moreover, different research groups are currently developing smart orthopaedic implants (plates, intramedullary nails and external fixators), able to provide information about the fracture healing process. These devices could significantly improve orthopaedic and trauma clinical practice in the future and, at the same time, reduce patients' exposure to X-rays. This study aims to define the role of traditional imaging techniques and emerging technologies in the assessment of the fracture healing process.

Assessment of union in fractures: Role of Serum Alkaline Phosphatase and Ultrasonography

INTRODUCTION

Fracture union is a fundamental goal in orthopaedics. There is variability in assessment and lack of consensus on reliability of various methods to evaluate progress of union. The purpose of this study was to study the temporal association of non-conventional methods i.e. Serum Alkaline Phosphatase (ALP) and Ultrasound (USG) in assessment of fracture healing with reference to plain radiographs (X-ray).

METHODOLOGY

This was a prospective observational cohort study of 161 adult patients with surgically treated long bone diaphyseal fractures. Plain radiographs, ALP and USG evaluation was done every 6 weekly for 6 months. USG evaluation included assessment of echogenicity and Doppler measurement of Vascular Resistance Index (RI) of callus. Fractures were considered united when X-ray showed bridging callus. ALP and USG changes over the follow-up period were analysed based on the final outcome of fractures.

RESULTS AND CONCLUSION

151 patients showed signs of fracture union at final follow-up. ALP which peaked at 6 weeks in all cases always remained within the laboratory reference range in cases progressing to union; whereas in cases of non-union the levels recorded higher. ALP value was the earliest positive predictor showing progress towards union. Beyond 12 weeks, Hyperechogenicity on Gray scale USG and serial measurement of RI on Doppler USG were found to better confirm progress in fracture union than X-rays. Combined evaluations of ALP and USG appear as promising investigations in assessment of the progress in fracture union.

Sonographic bridging callus: An early predictor of fracture union

BACKGROUND

There is currently a lack of agreed criteria for sonographic assessment of callus and reliability between reviewers. The primary aim of this study was to determine criteria and reviewer agreement for sonographic bridging callus (SBC) on ultrasound. The secondary aim was to analyse the use of ultrasound to detect bridging callus in a prospective cohort of patients with a conservatively managed clavicle fracture.

METHODS

A prospective cohort of conservatively managed displaced midshaft clavicle fractures underwent ultrasound scanning at three-, six- and 12-weeks post-injury. The main outcome was nonunion confirmed at six months on CT scanning. Five patients with confirmed nonunion were compared against a control group of 15 patients with timely union at three months. The ultrasound scans were interpreted by two blinded reviewers to evaluate sonographic callus features with agreement determined by weighted kappa. A further validation study was undertaken by four blinded reviewers using the intraclass-correlation-coefficient (ICC) using the most clinically relevant findings of the pilot work.

RESULTS

At three weeks post-injury fibrocartilaginous material was present in 80% of patients (16/20). When detected this was associated with union (sensitivity 93%, specificity 60%, p = 0.03) with the inter-observer agreement rated 'fair' on kappa (0.44). At six weeks only 10% (2/20) of patients had bridging callus on radiograph but 60% (12/20) had sonographic bridging callus (SBC) and when present all united (sensitivity 80%, specificity 100%, p = 0.002). At 12 weeks, bridging callus was present on both radiographs and ultrasound in all patients that united (n = 15, sensitivity 100%, specificity 100%, p < 0.001). No patient that developed a nonunion at six months post-injury had SBC at any time point. At six-weeks the absence of SBC had a positive predictive value for nonunion of 63% of patients (5/8) and by 12 weeks it was 100% (5/5). The SBC detection rated 'very strong' for intra- (kappa 0.92) and inter-observer agreement (kappa 0.84). The ICC of SBC at six-weeks with four blinded reviewers was 0.82 (95% confidence interval 0.68-0.91).

CONCLUSIONS

This is the first study to establish time specific ultrasound fracture findings with a repeatable technique and assess the agreement between blinded reviewers.

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

Objectives

The aim of this study was to review the current evidence and future application for the role of diagnostic and therapeutic ultrasound in fracture management.

Methods

A review of relevant literature was undertaken, including articles indexed in PubMed with keywords "ultrasound" or "sonography" combined with "diagnosis", "fracture healing", "impaired fracture healing", "nonunion", "microbiology", and "fracture-related infection".

Results

The use of ultrasound in musculoskeletal medicine has expanded rapidly over the last two decades, but the diagnostic use in fracture management is not routinely practised. Early studies have shown the potential of ultrasound as a valid alternative to radiographs to diagnose common paediatric fractures, to detect occult injuries in adults, and for rapid detection of long bone fractures in the resuscitation setting. Ultrasound has also been shown to be advantageous in the early identification of impaired fracture healing; with the advent of 3D image processing, there is potential for wider adoption. Detection of implant-related infection can be improved by ultrasound mediated sonication of microbiology samples. The use of therapeutic ultrasound to promote union in the management of acute fractures is currently a controversial topic. However, there is strong in vitro evidence that ultrasound can stimulate a biological effect with potential clinical benefit in established nonunions, which supports the need for further investigation.

Conclusion

Modern ultrasound image processing has the potential to replace traditional imaging modalities in several areas of trauma practice, particularly in the early prediction of impaired fracture healing. Further understanding of the therapeutic application of ultrasound is required to understand and identify the use in promoting fracture healing.Cite this article: J. A. Nicholson, S. T. J. Tsang, T. J. MacGillivray, F. Perks, A. H. R. W. Simpson. What is the role of ultrasound in fracture management? Diagnosis and therapeutic potential for fractures, delayed unions, and fracture-related infection. Bone Joint Res 2019;8:304-312. DOI: 10.1302/2046-3758.87.BJR-2018-0215.R2.

Radiologic evaluation of fracture healing

While assessment of fracture healing is a common task for both orthopedic surgeons and radiologists, it remains challenging due to a lack of consensus on imaging and clinical criteria as well as the lack of a true gold standard. Further complicating this evaluation are the wide variations between patients, specific fracture sites, and fracture patterns. Research into the mechanical properties of bone and the process of bone healing has helped to guide the evaluation of fracture union. Development of standardized scoring systems and identification of specific radiologic signs have further clarified the radiologist's role in this process. This article reviews these scoring systems and signs with regard to the biomechanical basis of fracture healing. We present the utility and limitations of current techniques used to assess fracture union as well as newer methods and potential future directions for this field.

Ultrasonography as a Diagnostic, Therapeutic, and Research Tool in Orthopaedic Surgery

Ultrasonography is an imaging modality that facilitates the diagnosis of pathology and injection therapy without exposing the patient to radiation. In addition, ultrasonography has become popular because of its portability, low cost, and production of real-time tomographic images that provide a cross-sectional view of anatomic structures. Despite its benefits and widespread adoption in general medicine and other specialties, however, ultrasonography is not as well adapted as a diagnostic and research tool in orthopaedic surgery. An understanding of the basic principles of ultrasonography and the evidence supporting its use can aid the orthopaedic surgeon in applying this modality appropriately in clinical practice.

Evaluation of Imaging Parameters of Ultrasound Scanners: Baseline for Future Testing

Background

Regular quality control is required in Poland only for those methods of medical imaging which involve the use of ionizing radiation but not for ultrasonography. It is known that the quality of ultrasound images may be affected by the wearing down or malfunctioning of equipment.

Material/Methods

An evaluation of image quality was carried out for 22 ultrasound scanners equipped with 46 transducers. The CIRS Phantom model 040GSE was used. A set of tests was established which could be carried out with the phantom, including: depth of penetration, dead zone, distance measurement accuracy, resolution, uniformity, and visibility of structures.

Results

While the dead zone was 0 mm for 89% of transducers, it was 3 mm for the oldest transducer. The distances measured agreed with the actual distances by 1 mm or less in most cases, with the largest difference of 2.6 mm. The resolution in the axial direction for linear transducers did not exceed 1 mm, but it reached even 5 mm for some of the convex and sector transducers, especially at higher depths and in the lateral direction. For 29% of transducers, some distortions of anechoic structures were observed. Artifacts were detected for several transducers.

Conclusions

The results will serve as a baseline for future testing. Several cases of suboptimal image quality were identified along with differences in performance between similar transducers. The results could be used to decide on the applicability of a given scanner or transducer for a particular kind of examination.