Minimal Detectable Bone Fracture Gaps in CT Images and Digital Three-Dimensional (3D) Radii Models.

Knowledge of the minimal detectable bone fracture gap is essential in three-dimensional (3D) models, particularly in pre-operative planning of osteosynthesis to avoid overlooking gaps. In this study, defined incisions and bony displacements ranging from 100 to 400 µm were created in diaphyseal radii in 20 paired forearm specimens and verified with light microscopy. The specimens were scanned utilizing different computed tomography (CT) technologies/scanners, specimen positionings, scan protocols, image segmentations, and processing protocols. Inter- and intra-operator variabilities were reported as coefficient kappa. In CT images, fracture gaps of 100 µm and bone lamellae of 300 µm and 400 µm width were identified at a rate of 80 to 100%, respectively, independent of the investigated settings. In contrast, only 400µm incisions and bony displacements were visible in digital 3D models, with detection rates dependent on CT technology, image segmentation, and post-processing algorithm. 3D bone models based on state-of-the-art CT imaging can reliably visualize clinically relevant bone fracture gap sizes. However, verification of fractures to be surgically addressed should be verified with the original CT image series.

Standardized reporting of spine and sacroiliac joints in axial spondyloarthritis MRI: from the ESSR-Arthritis Subcommittee.

OBJECTIVES: Apply a modified Delphi-based approach and produce a practical, radiology-specific set of definitions for interpretation and standardization of the multiple MRI findings in axial spondyloarthritis (ax-SpA), specifically to aid the general radiologist with a musculoskeletal interest, working with gold standard basic MRI protocols. MATERIALS AND METHODS: We report the results of a modified Delphi-based consensus of 35 experts from 13 countries in the Arthritis Subcommittee of the European Society of Musculoskeletal Radiology (ESSR). Seventeen definitions were created (i.e., nine for the spine and eight for the sacroiliac joint) and two Delphi rounds were conducted on an electronic database, collated and revised by the project leader with agreement. Group leads were appointed for each definition following the first round. Final definitions included only those that reached a consensus > 80%; if > 50% agreed on exclusion consensus, definitions were excluded. Final results have been shared during the Arthritis meeting at the Annual ESSR Congress. RESULTS: Fourteen definitions, eight for the spine and six for the sacroiliac joint were agreed for standardized reporting. Andersson's, anterior corner sclerotic and costovertebral joint inflammatory lesions of the spine, with active and non-active erosions, and fat metaplasia of the sacroiliac joint reaching the highest consensus (≥ 95%). More than 50% of the experts agreed to exclude joint space inflammation in the sacroiliac joint and tissue backfill. Syndesmophytes reached 76% agreement. CONCLUSIONS: Agreed definitions by expert radiologists using a modified Delphi process, should allow standardized actionable radiology reports and clarity in reporting terminology of ax-SpA. CLINICAL RELEVANCE STATEMENT: The proposed definitions will support reporting from musculoskeletal and general radiologists working with gold-standard basic MRI, improve confidence in lesion assessment, and standardize terminology to provide actionable reports on MRI in patients with ax-SpA. KEY POINTS: Experts applied a modified Delphi method to optimize the definitions of MRI findings of ax-SpA. After two Delphi rounds and one in-person meeting, fourteen definitions reached the agreement threshold. These consensus-based definitions will aid in actionable reporting specifically for the general radiologist with a musculoskeletal interest.

Recurrent medical imaging exposures for the care of patients: one way forward.

Medical imaging is both valuable and essential in the care of patients. Much of this imaging depends on ionizing radiation with attendant responsibilities for judicious use when performing an examination. This responsibility applies in settings of both individual as well as multiple (recurrent) imaging with associated repeated radiation exposures. In addressing the roles and responsibilities of the medical communities in the paradigm of recurrent imaging, both the International Atomic Energy Agency (IAEA) and the American Association of Physicists in Medicine (AAPM) have issued position statements, each affirmed by other organizations. The apparent difference in focus and approach has resulted in a lack of clarity and continued debate. Aiming towards a coherent approach in dealing with radiation exposure in recurrent imaging, the IAEA convened a panel of experts, the purpose of which was to identify common ground and reconcile divergent perspectives. The effort has led to clarifying recommendations for radiation exposure aspects of recurrent imaging, including the relevance of patient agency and the provider-patient covenant in clinical decision-making. CLINICAL RELEVANCE STATEMENT: An increasing awareness, generating some lack of clarity and divergence in perspectives, with patients receiving relatively high radiation doses (e.g., ≥ 100 mSv) from recurrent imaging warrants a multi-stakeholder accord for the benefit of patients, providers, and the imaging community. KEY POINTS: • Recurrent medical imaging can result in an accumulation of exposures which exceeds 100 milli Sieverts. • Professional organizations have different perspectives on roles and responsibilities for recurrent imaging. • An expert panel reconciles differing perspectives for addressing radiation exposure from recurrent medical imaging.

Accuracy Analysis of 3D Bone Fracture Models: Effects of Computed Tomography (CT) Imaging and Image Segmentation.

The introduction of three-dimensional (3D) printed anatomical models has garnered interest in pre-operative planning, especially in orthopedic and trauma surgery. Identifying potential error sources and quantifying their effect on the model dimensional accuracy are crucial for the applicability and reliability of such models. In this study, twenty radii were extracted from anatomic forearm specimens and subjected to osteotomy to simulate a defined fracture of the distal radius (Colles' fracture). Various factors, including two different computed tomography (CT) technologies (energy-integrating detector (EID) and photon-counting detector (PCD)), four different CT scanners, two scan protocols (i.e., routine and high dosage), two different scan orientations, as well as two segmentation algorithms were considered to determine their effect on 3D model accuracy. Ground truth was established using 3D reconstructions of surface scans of the physical specimens. Results indicated that all investigated variables significantly impacted the 3D model accuracy (p < 0.001). However, the mean absolute deviation fell within the range of 0.03 ± 0.20 to 0.32 ± 0.23 mm, well below the 0.5 mm threshold necessary for pre-operative planning. Intra- and inter-operator variability demonstrated fair to excellent agreement for 3D model accuracy, with an intra-class correlation (ICC) of 0.43 to 0.92. This systematic investigation displayed dimensional deviations in the magnitude of sub-voxel imaging resolution for all variables. Major pitfalls included missed or overestimated bone regions during the segmentation process, necessitating additional manual editing of 3D models. In conclusion, this study demonstrates that 3D bone fracture models can be obtained with clinical routine scanners and scan protocols, utilizing a simple global segmentation threshold, thereby providing an accurate and reliable tool for pre-operative planning.

Diffuse idiopathic skeletal hyperostosis as a cause for dysphagia in a patient with ankylosing spondylitis.

BACKGROUND: Diffuse idiopathic skeletal hyperostosis (DISH) is characterized by ankylosing spinal alterations which are often asymptomatic but may typically cause back pain and spinal stiffness. Presence of DISH may complicate spinal trauma and lead to unstable fractures requiring surgical intervention. Treatment options include physical activity, symptomatic treatment, local heat application, and optimization of metabolic comorbidities. CASE: A multimorbid older patient was admitted to the gastroenterological ward for the investigation of progressive dysphagia and weight loss. Gastroscopy revealed a dorsal impression of the esophagus at 25 cm from the incisor. Clinical work-up including computed tomography (CT) and magnetic resonance imaging (MRI) ruled out malignancy but showed ankylosing spondylophytes and non-recent fractures of vertebrae C5-C7, compatible with DISH of the cervicothoracic spine as a cause for the esophageal impression. Notably, imaging diagnostics showed ankylosing spine alterations extending to the lumbar spine and both sacroiliac joints, suggestive of ankylosing spondylitis (AS). Typical imaging characteristics, a history of psoriasis, and positive HLA*B27 status supported the diagnosis of underlying AS in this patient with dysphagia as an unusual primary symptom of DISH. Additionally, pulmonary alterations compatible with a usual interstitial pneumonia (UIP)-like pattern were seen on lung CT. CONCLUSION: Overlaps among AS, DISH and pulmonary abnormalities including UIP have been described previously; however, they represent unexpected findings in this older patient. This case underlines the importance of interdisciplinary collaboration and consideration of DISH as a differential diagnosis in patients with atypical symptoms.

Prescribing Exercise to Cancer Patients Suffering from Increased Bone Fracture Risk Due to Metastatic Bone Disease or Multiple Myeloma in Austria-An Inter- and Multidisciplinary Evaluation Measure.

INTRODUCTION: In the current absence of specific functional fracture risk assessment technology, the planning of physical exercise interventions for cancer patients suffering from increased bone fracture risk remains a serious clinical challenge. Until a reliable, solely technical solution is available for the clinician, fracture risk assessment remains an inter- and multidisciplinary decision to be made by various medical experts. The aim of this short paper is depicting how this challenge should be approached in the clinical reality according to Austrian experts in cancer rehabilitation, presenting the best-practice model in Austria. Following referral from the specialist responsible for the primary cancer treatment (oncologist, surgeon, etc.), the physiatrist takes on the role of rehabilitation case manager for each individual patient. Fracture risk assessment is then undertaken by specialists in radiology, orthopedics, oncology, and radiation therapy, with the result that the affected bone regions are classified as being at highly/slightly/not increased fracture risk. Following internal clearance, exercise planning is undertaken by a specialist in exercise therapy together with the physiatrist based on the individual's fracture risk assessment. In the case in which the patient shows exercise limitations due to additional musculoskeletal impairments, adjuvant physical modalities such as physiotherapy should be prescribed to increase exercisability. CONCLUSION: Exercise prescription for cancer patients suffering from increased fracture risk is an inter- and multidisciplinary team decision for each individual patient.

The intercondylar fossa-A narrative review.

The intercondylar fossa ("intercondylar notch," IN) is a groove at the distal end of the femur, housing important stabilizing structures: cruciate ligaments and meniscofemoral ligaments. As the risk for injury to these structures correlates with changes to the IN, exact knowledge of its morphology, possible physiological and pathological changes and different approaches for evaluating it are important. The divergent ways of assessing the IN and the corresponding measurement methods have led to various descriptions of its possible shapes. Ridges at the medial and lateral wall are considered clinically important because they can help with orientation during arthroscopy, whereas ridges at the osteochondral border could affect the risk of ligament injury. Changes related to aging and sex differences have been documented, further emphasizing the importance of individual assessment of the knee joint. Overall, it is of the utmost importance to remember the interactions between the osseous housing and the structures within.

Long-Term Outcomes of Adjuvant Denosumab in Breast Cancer.

BACKGROUND: Adjuvant aromatase inhibitors increase osteoporosis and fractures in patients with hormone receptor­positive breast cancer. We have previously reported outcomes of the ABCSG-18 (study 18 from the Austrian Breast & Colorectal Cancer Study Group) trial showing that adjuvant anti­receptor activator of nuclear factor-κB ligand denosumab treatment counteracts these adverse effects and may improve outcomes. We report here the final long-term outcomes. METHODS: ABCSG-18 is a prospective, double-blind, placebo-controlled, phase 3 trial in which 3425 postmenopausal patients with early hormone receptor­positive breast cancer receiving aromatase inhibitor therapy were randomly assigned in 58 trial centers to receive either denosumab 60 mg or placebo administered subcutaneously every 6 months. The primary end point was the time to first clinical fracture after randomization. Secondary disease outcome­related end points were disease-free survival (DFS), bone metastasis­free survival (BMFS), and overall survival (OS). RESULTS: For this final protocol-defined analysis, median follow-up is 8 years (interquartile range, 6 to 9.6 years). There were 309 versus 368 DFS events (hazard ratio, 0.83; 95% confidence interval [CI], 0.71 to 0.97) in the denosumab versus the placebo group, respectively, resulting in an absolute 9-year DFS benefit of 3.5 percentage points (79.4 vs. 75.9%). Adjuvant denosumab improved BMFS by 2.5 percentage points (88.9 vs. 86.4%; hazard ratio, 0.81; 95% CI, 0.65 to 1.00) and OS by 1.0 percentage point (90.9 vs. 89.9%; hazard ratio, 0.80; 95% CI, 0.64 to 1.01). No new toxicities for this dose of adjuvant denosumab were observed. CONCLUSIONS: DFS, BMFS, and OS continued to show benefit in this final long-term analysis of ABCSG-18. There were no new toxicities. (Funded by Amgen; ClinicalTrials.gov number, NCT00556374.)

Thermal Effects during Bone Preparation and Insertion of Osseointegrated Transfemoral Implants.

BACKGROUND: The preparation of bone for the insertion of an osseointegrated transfemoral implant and the insertion process are performed at very low speeds in order to avoid thermal damages to bone tissue which may potentially jeopardize implant stability. The aim of this study was to quantify the temperature increase in the femur at different sites and insertion depths, relative to the final implant position during the stepwise implantation procedure. METHODS: The procedure for installation of the osseointegrated implant was performed on 24 femoral specimens. In one specimen of each pair, the surgery was performed at the clinically practiced speed, while the speed was doubled in the contralateral specimen. Six 0.075 mm K fine gauge thermocouples (RS Components, Sorby, UK) were inserted into the specimen at a distance of 0.5 mm from the final implant surface, and six were inserted at a distance of 1.0 mm. RESULTS: Drilling caused a temperature increase of <2.5 °C and was not statistically significantly different for most drill sizes (0.002 < p < 0.845). The mean increase in temperature during thread tapping and implant insertion was <5.0 °C, whereas the speed had an effect on the temperature increase during thread tapping. CONCLUSIONS: Drilling is the most time-consuming part of the surgery. Doubling the clinically practiced speed did not generate more heat during this step, suggesting the speed and thus the time- and cost-effectiveness of the procedure could be increased. The frequent withdrawal of the instruments and removal of the bone chips is beneficial to prevent temperature peaks, especially during thread tapping.

History Page: Leaders in MSK Radiology.

Robert Kienböck (1871-1953) may be regarded as one of the first musculoskeletal radiologists who began his clinical and scientific work 2 years after the discovery of X-rays. He lent his name to Kienböck's disease, a traumatic malacia and osteonecrosis of the lunate, and to several other eponyms of diseases, devices, and parameters in radiology and radiation oncology. With his meticulous analysis of radiographic images of the highest quality, he anticipated many theories that were proposed in later decades.

Cancer rehabilitation: current trends and practices within an Austrian University Hospital Center.

Background: Cancer rehabilitation has the goal to improve functional status, quality of life, participation, and can improve quality of patient-centered programs and health care efficiencies. In Austria, inpatient cancer rehabilitation is well established but outpatient rehabilitation has not yet established well.Methods: The present article is describing current rehabilitation in practice and focuses on cancer rehabilitation in Austria, namely bringing together a descriptive account of current trends and practices within an Austrian University Hospital Center (General Hospital of Vienna linked to the Medical University of Vienna) and the Comprehensive Cancer Centre (CCC) Vienna, Austria.Results: Cancer Rehabilitation in the described Austrian University Hospital Center is well developed due to the help of all different clinics dealing with cancer patients and of the opinion leaders of the CCC Vienna. The Department of Physical Medicine, Rehabilitation, and Occupational Medicine of the Medical University of Vienna as a part of the CCC Vienna with his "Pioneer-Status" and the described milestones has been integrated in the national cancer rehabilitation concept of our country from the beginning.Conclusions: Also in Austria, Physical Medicine and Rehabilitation with competencies in diagnostic and therapy as well as of coordination of the multiprofessional and interdisciplinary rehabilitation teams is an important part of cancer rehabilitation.Implications for rehabilitationCancer rehabilitation is an important part in the treatment and care of cancer patients with the goal to improve functional status, quality of life, and participationCancer rehabilitation helps cancer survivors to be integrated in their normal live, namely to increase social participation and/or workabilityThe field of Physical Medicine and Rehabilitation with competencies in diagnostic and therapy as well as of coordination of the multi-professional and interdisciplinary rehabilitation teams is an important part of cancer rehabilitationInterventions and treatment approaches from the field of Physical Medicine and rehabilitation include the application of Physical Modalities like electrotherapy, thermotherapy, balneology and climatic therapy, phototherapy, and mechanotherapy Cancer rehabilitation has to be early integrated into the cancer care continuum.

QCT-based finite element prediction of pathologic fractures in proximal femora with metastatic lesions.

Predicting pathologic fractures in femora with metastatic lesions remains a clinical challenge. Currently used guidelines are inaccurate, especially to predict non-impeding fractures. This study evaluated the ability of a nonlinear quantitative computed tomography (QCT)-based homogenized voxel finite element (hvFE) model to predict patient-specific pathologic fractures. The hvFE model was generated highly automated from QCT images of human femora. The femora were previously loaded in a one-legged stance setup in order to assess stiffness, failure load, and fracture location. One femur of each pair was tested in its intact state, while the contralateral femur included a simulated lesion on either the superolateral- or the inferomedial femoral neck. The hvFE model predictions of the stiffness (0.47 < R2 < 0.94), failure load (0.77 < R2 < 0.98), and exact fracture location (68%) were in good agreement with the experimental data. However, the model underestimated the failure load by a factor of two. The hvFE models predicted significant differences in stiffness and failure load for femora with superolateral- and inferomedial lesions. In contrast, standard clinical guidelines predicted identical fracture risk for both lesion sites. This study showed that the subject-specific QCT-based hvFE model could predict the effect of metastatic lesions on the biomechanical behaviour of the proximal femur with moderate computational time and high level of automation and could support treatment strategy in patients with metastatic bone disease.

Typical aspects in the rehabilitation of cancer patients suffering from metastatic bone disease or multiple myeloma.

BACKGROUND: The aim of this study was to present a practical concept focusing on typical aspects of regular physical activity, exercise and physical modalities for patients suffering from metastatic bone disease or multiple myeloma. METHODS: A narrative review of the relevant scientific literature and presentation of clinical experiences. RESULTS: In cancer patients with metastatic bone disease or multiple myeloma, pain is treated in an interdisciplinary and multimodal setting by using medication, radiotherapy and physical medical modalities (e.g. transcutaneous electrical nerve stimulation); however, modalities increasing local blood flow, such as ultrasound therapy, thermotherapy, massage, various electrotherapy options, are not performed at the site of the tumor. For physical activity and exercise, a suitable indication of the static and dynamic capacity of the affected skeletal structures is essential. This process includes strategies to maintain and improve mobility and independence. Individually tailored and adapted physical activity and exercise concepts (programs) within a multidisciplinary and interdisciplinary setting (tumor board) are used to manage the condition and bone load-bearing capacity of the patient. Typical clinical features and complications, such as pathological fractures in patients suffering from metastatic bone disease and additionally hypercalcemia, monoclonal gammopathy with bone marrow aplasia and risk of renal failure in patients with multiple myeloma have to be considered when planning supportive strategies and rehabilitation. CONCLUSION: In order to ensure the safety and effectiveness of regular physical activity, exercise, and physical modalities in patients with metastatic bone disease or multiple myeloma, typical contraindications and considerations should be noted.

Changes in Bone Mineral Density Following Weight Loss Induced by One-Anastomosis Gastric Bypass in Patients with Vitamin D Supplementation.

BACKGROUND: Little is known about changes in bone mineral density (BMD) following weight loss after one-anastomosis gastric bypass (OAGB) and the role of serum vitamin D and its supplementation on bone metabolism. We evaluated BMD after OAGB as a function of vitamin D supplementation with respect to a minimum threshold of 25-hydroxy-vitamin-D [25(OH)D] concentration, which could prevent or decelerate an eventual bone loss. METHODS: Fifty bariatric patients who participated in the randomized controlled trial were included in this analysis. BMD and anthropometric measurements by DXA and laboratory parameters were assessed before (T0), at 6 (T6), and 12 months (T12) after surgery. RESULTS: OAGB resulted in a 36% total body weight loss with a decrease in body fat and an increase in lean body mass. A significant decrease in BMD was seen in lumbar spine by 7%, left hip 13%, and total body 1%, but not in forearm. Bone turnover markers increased significantly but with normal parathyroid hormone concentrations. Weight loss was not associated with changes in BMD. A serum 25(OH)D concentration > 50 nmol/l at T6 and T12 (adequate-vitamin-D-group; AVD) showed a significant lower bone loss, compared to the inadequate-vitamin-D-group (IVD; < 50 nmol/l). Lower bone loss in the left hip showed a strong correlation with higher 25(OH)D concentrations (r = 0.635, p = 0.003). CONCLUSION: These findings support a dose effect of vitamin D supplementation on bone health and suggest that 25(OH)D concentrations need to be above 50 nmol/l at least during the first postoperative year to decelerate bone loss in patients undergoing OAGB. CLINICAL TRIAL REGISTRY NUMBER AND WEBSITE: Clinicaltrials.gov (NCT02092376) at https://clinicaltrials.gov /. EudraCT (2013-003546-16) at https://eudract.ema.europa.eu /.

Long-Term Course of Shoulders After Ultrasound Therapy for Calcific Tendinitis: Results of the 10-Year Follow-Up of a Randomized Controlled Trial.

OBJECTIVE: The aim of the study was to follow both the structure- and function-related long-term course of shoulders that had been treated with therapeutic ultrasound for symptomatic calcific tendinitis. DESIGN: This is a long-term follow-up of 45 shoulders (37 patients) that had been treated for symptomatic calcific tendinitis with either a series of ultrasound or sham ultrasound 10 yrs ago. The main outcome variables were presence of calcium deposits and subacromial impingement on standardized x-ray imaging, shoulder symptoms (Binder score), and function (Constant score). RESULTS: At 10 yrs, a similar proportion of calcium deposits had resolved in 78% of the originally ultrasound treated compared with 83% of sham-treated shoulders, whereas at 9 mos, significantly more calcium deposits had been resolved in the ultrasound group (P = 0.045). Relative to baseline, shoulder symptoms and function had significantly improved at both the 10-yr and 9-mo follow-up examinations with no significant differences between groups. Regular sports performance at baseline predicted a favorable long-term outcome. CONCLUSIONS: Symptomatic calcific tendinitis of the shoulder has a good likelihood to completely resolve in the long term. Treating the calcium deposit effectively, however, may not be causal to the recovery from symptoms and function in calcific tendinitis.

Evaluation of age-dependent morphometrics of the meniscofemoral ligaments in reference to the posterior cruciate ligament in routine MRI.

OBJECTIVES: To quantify the morphological correlation between the posterior cruciate ligament (PCL) and the meniscofemoral ligaments (MFLs), to propose normal ranges for different age populations, and to define guidelines for correct identification and differentiation of MFLs in routine MRI. METHODS: Three hundred forty-two subjects were included retrospectively and subdivided into five age groups. Morphometrics of the PCL and the MFLs were measured on standard MRI in the sagittal, coronal, and axial planes. Student's t test, Mann-Whitney U test, and ANOVA and Kruskal-Wallis tests with Bonferroni correction were used for comparison. RESULTS: The MFLs did not vary significantly between sexes (p > 0.05) or in those older than 10 years (p > 0.05). Longitudinal MFL growth is completed before age 11 years, with cross-sectional area (CSA) increasing until age 20. The CSA of the PCL was significantly (p = 0.028) larger in knees without a pMFL (Mdn = 39.7 mm2) than with a pMFL (Mdn = 35.4 mm2). MFLs were more often detected on sagittal than coronal images. CONCLUSIONS: This study describes the morphometric relation between the PCL and the MFLs on routine MRI. When reporting imaging findings in preparation for arthroscopic knee surgery, evaluation of MFLs, first in the sagittal and then the coronal plane, will achieve the best results. KEY POINTS: • The MFLs and the PCL have distinct morphological patterns throughout life. • These patterns show intimate anatomical relationships and a potential biomechanical impact. • Those patterns and relationships can be quantified with MRI. • A correlation exists between age and morphometrics of the MFLs. • Recommendations for correct identification of the MFLs are provided.

Detecting cam-type deformities on plain radiographs: what is the optimal lateral view?

PURPOSE: Radial magnetic resonance imaging (MRI) is the most accurate diagnostic tool in assessing cam-type femoroacetabular impingement. Plain radiographs, however, are useful for the initial diagnosis in the daily practice and there is still debate regarding the optimal lateral view. The purpose of this study was to investigate the reliability of detecting cam deformities using the frog-leg view or the 45° Dunn view by comparison with radial MRI. MATERIAL: 66 consecutive hips with plain radiographs (36 with AP and frog-leg views, 30 with AP and 45° Dunn views) and radial MRI were assessed. Alpha angle measurements were obtained both for radiographs and for radial MRI reformats by two investigators. Statistics included frequency analysis, bivariate linear correlation analyses, and cross-table analyses testing the sensitivity and specificity of the radiographic projections for detecting an alpha angle larger than 55°. RESULTS: The intra-class correlation revealed excellent agreement between the two raters [ICC = 0.959, CI (0.943; 0.972)]. 50% (33/66) had the maximum alpha angle in the superior-anterior aspect of the femoral head-neck junction. Cam deformity was found in 40/66 cases (61%) in radial MRI. Pearson correlation demonstrated that the 45° Dunn view was most accurate for the superior-anterior aspect (0.730, p < 0.05). The frog-leg view was best suited for the anterior aspect (0.703, p < 0.05). The sensitivity for detecting cam deformities in the 45° Dunn view was 84 vs 62% in the frog-leg view. CONCLUSION: The frog-leg lateral radiograph does not provide reliable measurements of the alpha angle. This study highlights the importance of the 45° Dunn view for early detection of femoroacetabular cam-type impingement.

Which MR sequences should we use for the reliable detection and localization of bone marrow edema in spondyloarthritis?

OBJECTIVES: To assess the diagnostic confidence in detecting and localizing areas of bone marrow edema in the sacroiliac joint of patients with suspected spondyloarthritis using a single-plane method and comparing it with multiplanar unenhanced and enhanced methods. MATERIALS AND METHODS: Patients with clinical suspicion of spondyloarthritis undergoing an MRI of the sacroiliac joint were included in this retrospective study. To assess sacroiliitis, three methods were applied: single-plane (i.e., para-coronal STIR alone), multiplanar unenhanced (i.e., para-coronal STIR and para-axial PD-fs), and multiplanar enhanced method (i.e., para-coronal and para-axial post-contrast T1-fs). Two 4-point scales were used to evaluate, respectively, the diagnostic confidence in detection and localization of bone marrow edema. The distribution of certain and uncertain rating according to signal intensity and size of the lesions was also calculated. RESULTS: Seventy-four patients met the inclusion criteria. Both multiplanar methods increased the diagnostic confidence in detection (p < 0.001) and localization (p < 0.001) of sacroiliitis; no significant difference occurred between the multiplanar unenhanced and enhanced methods (p = 0.405 and p = 1.00, respectively, for detection and localization). A statistically significant difference between the distributions of certain and uncertain rating for detection based on the size and signal intensity of each lesion emerged (p = 0.006 and p < 0.001, respectively), whereas no statistically significant difference occurred for the confidence of localization (p = 0.452 and p = 0.694, respectively). CONCLUSIONS: The multiplanar methods increased the diagnostic confidence in detection and localization of sacroiliitis. The absence of a significant difference between the proposed unenhanced and enhanced methods suggests that contrast medium is not mandatory for the detection of sacroiliitis.

Degeneration and Instability and the Relation to Patients' Function Late After Lumbar Disc Surgery: Data from a 12-Year Follow-Up.

OBJECTIVE: To investigate the excess risk of degeneration and segmental instability in operated segments late after lumbar disc surgery in patients with presurgically stable segments, and whether local pathological findings relate to patients' back health. DESIGN: This retrospective analysis reports on 69 patients 12 years after first-time, uncomplicated lumbar disc surgery. Two independent radiologists evaluated the patients' lumbar functional x-rays; the Back Pain Rating Score (LBP-RS) assessed back-specific function. RESULTS: At 12 years after lumbar disc surgery, degenerative changes as well as segmental instability occurred significantly more frequently in the operated than nonoperated lumbar segments, but there was no association between increased degeneration and segmental instability rates. The risk for acquiring segmental instability was significantly associated with surgery (odds ratio, 6.5; 95% confidence interval, 1.5-28.8). Prevalence of segmental instabilities was associated with better LBP-RS scores. Analyses of LBP-RS subscores revealed a clear association of segmental instability with physical function, but not with pain or activities of daily living. CONCLUSIONS: Lumbar disc surgery seems to be associated with an increased risk of degeneration and segmental instability in the long term. This structural impairment, however, seems functionally well compensated and does not seem to be a relevant causal factor for a chronic back pain syndrome. TO CLAIM CME CREDITS: Complete the self-assessment activity and evaluation online at http://www.physiatry.org/JournalCME CME OBJECTIVES:: Upon completion of this article, the reader should be able to: (1) Describe the impact of lumbar disc surgery on segmental instability and degenerative changes; (2) Recognize the lack of association between degenerative changes and segmental instability after lumbar disc surgery; and (3) State the value of lumbar spinal functional tests in the evaluation of patients after lumbar disc surgery. LEVEL: Advanced ACCREDITATION:: The Association of Academic Physiatrists is accredited by the Accreditation Council for Continuing Medical Education to provide continuing medical education for physicians. The Association of Academic Physiatrists designates this activity for a maximum of 1.5 AMA PRA Category 1 Credit(s)™. Physicians should only claim credit commensurate with the extent of their participation in the activity.