Miss Katie Clark: Pioneer of Standardization of Radiographic Projections.

This history page in the series "Leaders in MSK radiology" is dedicated to the memory and achievements of the British radiographer Kathleen C. Clark, recognized as a pioneer of standardization of radiographic projections.

Imaging of thoracolumbar spine traumas.

Spine trauma is an ominous event with a high morbidity, frequent mortality, and significant psychological, social, and financial consequences for patients, their relatives and society. On average three out of four spinal fractures involve the thoracolumbar spine and up to one-third are complicated by spinal cord injury. Spinal cord injuries (SCI) are a significant cause of disability in US and in all western countries. Knowledge of the main principles of biomechanics is essential in understanding the patho-morphology of spinal injuries, and the evolution of the various classification systems. Classification systems should be able to create a common language between specialists in order to improve patients' prognosis, guide treatment and compare treatment outcomes. Imaging has always been crucial in the evaluation of the injury type and accompanied the development of different classification systems. Thoracolumbar spine (TLS) trauma has a wide spectrum ranging from minor isolated fractures to highly unstable fracture-dislocations. Early classification systems were based on the analysis of the pattern of bony injuries on radiographs and CT. Traditionally, conventional radiographs are performed to confirm the clinical suspicion and to depict the level and type of bone injury. However, because of their inherent limitations, radiographs are often more helpful in proving the existence of a suspected bony spinal injury rather than excluding it. Multidetector computed tomography (MDCT) is superior in evaluating bone anatomy and, especially in polytrauma patients, it is the first line imaging modality. Morphological bone damage may be accurately shown and classified on CT. the most recent classifications also incorporate the integrity of soft tissues structures, which is considered equally relevant to spinal stability. Injuries to ligaments and discs can only be suspected on radiographs and conventional CT, although dual-energy CT is offering new insights on collagen mapping of damaged discs. Magnetic resonance imaging (MRI) may directly assess disc and ligamentous injuries, but also subtle osseous injuries, playing a complementary role in defining the whole spinal damage and an eventual instability. MRI is the only valid modality to assess the spinal cord (SC) and is indicated whenever a neurologic injury is suspected. Advanced MRI techniques, such as diffusion weighted imaging (DWI) and tractography, may provide further information regarding the integrity of the white matter which may improve outcome prognostication. Despite challenges in terms of costs, availability, accessibility and specificity, MRI and advanced MRI techniques are increasingly being used in spinal injuries. We present a review on TLS traumas discussing on the development of different classification system used in their evaluation, the role of imaging for their detection and the correlation to the patients' outcomes and treatment options.

A novel use of cone beam CT: flexion and extension weight-bearing imaging to assess spinal stability.

PURPOSE: To assess spinal stability in different physiological positions whilst weight-bearing. METHODS: A cone beam CT scanner (CBCT) was used to identify any abnormal motion in the spine in different physiological positions whilst weight-bearing. The lumbar spine was assessed in 6 different patients with a comfortable neutral standing position and standing flexion and extension images in selected patients. Seated, weight-bearing flexion and extension images of the cervical spine were obtained in a further patient. Clinical indications included stability assessment post-trauma, post-surgical fusion and back pain. The projection images were reconstructed using bone and soft tissue algorithms to give isotropic CT images which could be viewed as per conventional multi-detector CT images. The flexion and extension CBCT data were fused to give a representation of any spinal movement between the extremes of motion. RESULTS: The flexion and extension weight-bearing images gave anatomical detail of the spine. Detail of the surgical constructs was possible. Dynamic structural information about spinal alignment, facet joints, exit foramina and paraspinal musculature was possible. The effective dose from the neutral position was equal to that of supine, multi-detector CT. CONCLUSION: CBCT can be used to image the lumbar and cervical spine in physiological weight-bearing positions and at different extremes of spinal motion. This novel application of an existing technology can be used to aid surgical decision making to assess spinal stability and to investigate occult back and leg pain. Its use should be limited to specific clinical indications, given the relatively high radiation dose.

Neoplastic Elbow Diseases and Mimickers.

Tumors around the elbow are infrequent, and delayed diagnosis is a common theme because of the low incidence and lack of familiarity. However, just like any other site, the radiologic work-up of musculoskeletal tumors around the elbow remains the same, with plain films the first investigation in a patient with a suspected bone tumor and ultrasound the first modality to evaluate a soft tissue lump. The management of both bone and soft tissue tumors around the elbow is unique because of a large number of important structures in an anatomically confined space and little normal tissue to spare without severely compromising the joint's function. Many benign nonneoplastic entities can mimic bone and soft tissue tumors on imaging. It is important to keep the characteristic imaging appearance in mind while formulating a differential diagnosis to avoid an unnecessary additional work-up. This article reviews the most common benign and malignant bone and soft tissue tumors around the elbow, mimickers, imaging features, and current therapeutic concepts.

Intraosseous lipomas originating from simple bone cysts.

PURPOSE: Fatty or part-fatty intraosseous lesions are occasionally encountered while imaging the skeletal system. A number of case reports have proposed involution of calcaneal bone cysts to intraosseous lipomas, but this has never been proven. This paper sets out to prove that simple bone cysts (SBCs) can involute to fatty lesions indistinguishable from intraosseous lipomas. MATERIALS AND METHODS: The pathology and PACS databases at 2 specialist orthopedic hospitals were retrospectively interrogated for all cases of intraosseous lipomas or SBCs with cross-sectional imaging follow-up for SBCs and precursor or follow-up imaging for intraosseous lipomas, in the time period from August 2007 to December 2016. For intraosseous lipoma cases, these were only included if change in imaging appearances was observed. RESULTS: There was no case of change in the appearance in intraosseous lipomas. Six cases of SBC with cross-sectional imaging follow-up were identified in one participating hospital and none in the other. The 6 cases were comprised of 4 male and 2 female patients. Two were located in the proximal humerus, one in the proximal tibia, and 3 in the os calcis. All cases demonstrated filling in of the cystic lesion with fat from the periphery, in 2 cases complete filling in, and in 4 cases partial fatty conversion. CONCLUSION: SBCs can heal with fatty conversion of the cystic cavity, with partly cystic remnants. It is proposed that at least part of the so-called intraosseous lipomas are healed simple bone cysts.

Stress Injuries of the Spine in Sports.

Spine sports stress injuries account for a significant amount of time loss at play in athletes, particularly if left unrecognized and allowed to progress. Spondylolysis makes up most of these stress injuries. This article focuses on spondylolysis, bringing together discussion from the literature on its pathomechanics and the different imaging modalities used in its diagnosis. Radiologists should be aware of the limitations and more importantly the roles of different imaging modalities in guiding and dictating the management of spondylolysis. Other stress-related injuries in the spine are also discussed including but not limited to pedicle fracture and apophyseal ring injury.

Radiographic/MR Imaging Correlation of Spinal Bony Outlines.

The human spine is a highly specialized structure that protects the neuraxis and supports the body during movement, but its complex structure is a challenge for imaging. Radiographs can provide fine bony detail, but lack soft tissue definition and can be complicated by overlying structures. MR imaging allow(s) excellent soft tissue contrast, but some bony abnormalities can be difficult to discern. This makes the 2 modalities highly complementary. In this article, the authors discuss the correlation between radiographic and MR imaging appearances focusing first on disease affecting the vertebral body itself, its surrounding structures, and finally global spinal alignment.

Imaging of Upper Limb Tumors and Tumorlike Pathology.

Bone and soft tissue sarcomas are uncommon tumors that can occur within the upper extremity as well as elsewhere within the body. However, certain histopathological subtypes have increased affinity for the upper limb and even certain sites within the arm and hand. Other benign masses and tumor mimics, such as infection and traumatic lesions, are more common and imaging appearances can sometimes overlap with malignant lesions making diagnosis difficult. In this article, we explore the current options for imaging of these lesions as well as typical imaging appearances of the more common upper limb tumors.

Diagnosis of peripheral bone and prosthetic joint infections: overview on the consensus documents by the EANM, EBJIS, and ESR (with ESCMID endorsement).

OBJECTIVES: Peripheral bone infection (PBI) and prosthetic joint infection (PJI) are two different infectious conditions of the musculoskeletal system. They have in common to be quite challenging to be diagnosed and no clear diagnostic flowchart has been established. Thus, a conjoined initiative on these two topics has been initiated by the European Society of Radiology (ESR), the European Association of Nuclear Medicine (EANM), the European Bone and Joint Infection Society (EBJIS), and the European Society of Clinical Microbiology and Infectious Diseases (ESCMID). The purpose of this work is to provide an overview on the two consensus documents on PBI and PJI that originated by the conjoined work of the ESR, EANM, and EBJIS (with ESCMID endorsement). METHODS AND RESULTS: After literature search, a list of 18 statements for PBI and 25 statements for PJI were drafted in consensus on the most debated diagnostic challenges on these two topics, with emphasis on imaging. CONCLUSIONS: Overall, white blood cell scintigraphy and magnetic resonance imaging have individually demonstrated the highest diagnostic performance over other imaging modalities for the diagnosis of PBI and PJI. However, the choice of which advanced diagnostic modality to use first depends on several factors, such as the benefit for the patient, local experience of imaging specialists, costs, and availability. Since robust, comparative studies among most tests do not exist, the proposed flowcharts are based not only on existing literature but also on the opinion of multiple experts involved on these topics. KEY POINTS: • For peripheral bone infection and prosthetic joint infection, white blood cell and magnetic resonance imaging have individually demonstrated the highest diagnostic performance over other imaging modalities. • Two evidence- and expert-based diagnostic flowcharts involving variable combination of laboratory tests, biopsy methods, and radiological and nuclear medicine imaging modalities are proposed by a multi-society expert panel. • Clinical application of these flowcharts depends on several factors, such as the benefit for the patient, local experience, costs, and availability.

Correction to: Consensus document for the diagnosis of prosthetic joint infections: a joint paper by the EANM, EBJIS, and ESR (with ESCMID endorsement).

The authors regret to inform the readers that one of the author's name in the original publication of this article was spelled incorrectly as Victor Casar-Pullicino. The correct spelling is Victor N. Cassar-Pullicino and is now presented correctly in this article.

Consensus document for the diagnosis of peripheral bone infection in adults: a joint paper by the EANM, EBJIS, and ESR (with ESCMID endorsement).

INTRODUCTION: In adults with a suspicion of peripheral bone infection, evidence-based guidelines in choosing the most accurate diagnostic strategy are lacking. AIM AND METHODS: To provide an evidence-based, multidisciplinary consensus document on the diagnostic management of adult patients with PBIs, we performed a systematic review of relevant infectious, microbiological, orthopedic, radiological, and nuclear medicine literature. Delegates from four European societies (European Bone and Joint Infection Society, European Society of Microbiology and Infectious Diseases, European Society or Radiology, and European Association of Nuclear Medicine) defined clinical questions to be addressed, thoroughly reviewed the literature pertinent to each of the questions, and thereby evaluated the diagnostic accuracy of each diagnostic technique. Inclusion of the papers per statement was based on a PICO (Population/problem - Intervention/indicator - Comparator - Outcome) question following the strategy reported by the Oxford Centre for Evidence-based Medicine. For each statement, the level of evidence was graded according to the 2011 review of the Oxford Centre for Evidence-based Medicine. All approved statements were addressed taking into consideration the available diagnostic procedures, patient acceptance, tolerability, complications, and costs in Europe. Finally, a commonly agreed-upon diagnostic flowchart was developed.

Consensus document for the diagnosis of prosthetic joint infections: a joint paper by the EANM, EBJIS, and ESR (with ESCMID endorsement).

BACKGROUND: For the diagnosis of prosthetic joint infection, real evidence-based guidelines to aid clinicians in choosing the most accurate diagnostic strategy are lacking. AIM AND METHODS: To address this need, we performed a multidisciplinary systematic review of relevant nuclear medicine, radiological, orthopaedic, infectious, and microbiological literature to define the diagnostic accuracy of each diagnostic technique and to address and provide evidence-based answers on uniform statements for each topic that was found to be important to develop a commonly agreed upon diagnostic flowchart. RESULTS AND CONCLUSION: The approach used to prepare this set of multidisciplinary guidelines was to define statements of interest and follow the procedure indicated by the Oxford Centre for Evidence-based Medicine (OCEBM).

Predictors of fracture healing in patients with recalcitrant nonunions treated with autologous culture expanded bone marrow-derived mesenchymal stromal cells.

The study reports the prospective outcome of treating severe recalcitrant fracture nonunion in patients with autologous bone marrow-derived mesenchymal stromal cells (BMSC) from 2003 to 2010 and analyze predictors of union. Autologous BMSC were culture expanded and inserted at nonunion site with or without carriers in addition to surgical stabilization of the fracture. Radiological union was ascertained by musculoskeletal radiologists on plain radiographs and/or CT scans. A logistic regression analysis was performed with cell-expansion parameters (cell numbers, cell doubling time) and known clinical factors (e.g., smoking and diabetes) as independent variables and fracture union as the dependent variable to identify the factors that influence bony healing. An Eq5D index score assessed the effect of treatment on general quality of health. A total of 35 patients (mean age 51+/-13 years) with established nonunion (median 2.9 years, 1-33) and, at least one failed nonunion surgery (median 4,1-14) received treatment. Fracture union was achieved in 21 patients (60%; 95%CI 44-75) at 2.6 years. Multiple penalized logistic regression revealed faster cell doubling time (p = 0.07), absence of diabetes (p = 0.003), less previous surgeries (p = 0.008), and lower age at cell implantation (p = 0.02) were significant predictors for fracture union. A significant increase in Eq5D index (p = 0.01) was noted with a mean rise of the score by 0.34 units (95%CI 0.11-0.58) at 1 year following the study. In summary, the study revealed cell doubling time as a novel in vitro parameter in conjunction with age, multiple surgeries, and diabetes as being significant predictors of the fracture union. © 2018 The Authors. Journal of Orthopaedic Research® Published by Wiley Periodicals, Inc. J Orthop Res 37:1303-1309, 2019.

Computed Tomography and MR Imaging in Spondyloarthritis.

This article provides an overview of the computed tomography (CT) and MR imaging appearances suggestive of spondyloarthritis, with a specific emphasis on the MR imaging findings of vertebral and sacroiliac involvement, and presents relevant clinical features that assist early diagnosis. CT is a sensitive imaging modality for the assessment of structural bone changes, but its clinical utility is limited. MR imaging is the modality of choice for early diagnosis, because of its ability to depict inflammation long before structural bone damage occurs, for monitoring of disease activity, and for evaluating therapeutic response.

SAPHO and Recurrent Multifocal Osteomyelitis.

SAPHO and recurrent multifocal osteomyelitis are complex inflammatory conditions that clinical radiologists play an essential part in diagnosing. They present with a wide range of musculoskeletal and skin manifestations, and exhibit several key diagnostic features that, when present, make the diagnoses unequivocal. The overall population group is young. Diagnostic delay is common with a relapsing and remitting clinical course and often subtle early radiologic findings. This article provides an up-to-date insight into both conditions, including their multifaceted pathogenesis, effective therapeutic options, and advanced imaging features, to arm radiologists with the knowledge required to make the diagnoses confidently in a timely manner.

Multiple long bone cysts revealed by MRI in trichorhinophalangeal syndrome type II predisposing to pathological fractures.

Trichorhinophalangeal syndrome type II is a rare genetic disorder with the few published case reports mainly reporting the radiographic skeletal manifestations. There are no published imaging reports of long bone cysts involving multiple bones in this condition. We report a unique case of bone cysts involving multiple long bones detected with MRI in a patient with trichorhinophalangeal syndrome type II complicated by a subsequent pathological fracture. It is possible that the bone cysts are a previously undescribed feature of this syndrome; however, the evidence is insufficient to establish a definite association. Chromosomal abnormality identified in this patient is consistent with trichorhinophalangeal syndrome type II with no unusual features. Although the nature of these bone cysts is unclear, they are one of the causes of the known increased fracture risk observed in this syndrome.

Imaging of Paget's disease of bone.

Paget's disease of bone is a disorder of bone remodelling, leading to changes in the architecture and overall appearance of the bone. The disorder may be monostotic or polyostotic and affect any bone in the body, although most commonly it involves the spine, pelvis, skull and femur. This article explores the different imaging modalities used in the assessment of Paget's disease of bone in its different phases. The relative merits of each imaging modality is discussed with illustrative examples, in particular with respect to radiographs, nuclear medicine bone scan, computed tomography (CT) and magnetic resonance imaging (MRI).