Transcatheter arterial tendinopathy embolization as a treatment for painful and refractory tendinopathy: a systematic review and meta-analysis.

OBJECTIVE: Transcatheter arterial embolization (TAE) is a novel minimally invasive therapy for painful tendinopathy in patients with pain refractory to conservative management. The purpose of this study was to evaluate evidence on the efficacy of TAE for tendinopathy related pain. MATERIALS AND METHODS: Using Embase, PubMed, and Web of Science, a systematic review and meta-analysis was performed to identify studies evaluating TAE for painful tendinopathy. The primary outcome measure was change in pain scale score at 6 months. A Ratio of Means (ROM) was used to compare the effect size post treatment as compared to baseline. The Visual Analog Scale (VAS) was used as the metric for comparison. RESULTS: After screening titles, abstracts, and the full text, 5 studies met inclusion criteria. A total of 97 tendinopathy embolization procedures performed in 74 patients were included. Patients who underwent TAE demonstrated declines in VAS ROM at 1 day 0.53 [95% CI 0.31,0.88], 1 week (0.51 [95% CI 0.32,0.79]), 1 month (0.45 [95% CI 0.29, 0.71]), 3-4 months (0.33 [95% CI 0.22,0.48]), and 6 months following embolization (0.18[95% CI 0.13,0.26]), respectively. DISCUSSION: TAE provides substantial short-term reductions in pain scores for patients suffering with refractory tendinopathy related pain of the rotator cuff, elbow extensor and flexor, Achilles, and patellar tendons.

Reporting of Facet Joint Inflammation in Lumbar Spine MRI Studies in Patients With Low Back Pain.

STUDY DESIGN: Retrospective. OBJECTIVE: We aimed to assess the frequency of facet joint inflammatory features noted in routine radiology reports of lumbar spine magnetic resonance imaging (MRI) studies among patients with chronic low back pain. SUMMARY OF BACKGROUND DATA: Facet joint arthropathy is one of the most common causes of chronic low back pain. It may encompass various inflammatory imaging characteristics, such as facet joint effusion, bone marrow edema, and soft tissue edema. The extent to which radiology reports mention inflammatory features of the lumbar facet joints and the accuracy of these reports have not been investigated. MATERIALS AND METHODS: The authors performed a chart review on 49 subjects with previous facet-related interventions ( i.e . medial branch blocks or intra-articular facet joint injection) and MRI available in the medical record. One senior musculoskeletal radiologist and a musculoskeletal radiology fellow graded the inflammatory features using a published facet joint inflammation grading system [Gold Standard (GS)]. The authors identified the inflammatory markers mentioned in the radiology reports and calculated the sensitivity and positive predictive value of the radiology reports compared with GS readings. RESULTS: Compared with the GS, the sensitivity of radiology reports for facet joint effusion, bone marrow, and soft tissue edema ranged from 6% to 22%, and the positive predictive value ranged from 25% to 100%. L4/5 had the highest number of cases with inflammatory features noted on the reports. CONCLUSION: Inflammatory findings, such as facet joint effusion, bone marrow edema, and soft tissue edema, are not commonly identified in radiology reports. Further investigations are needed to determine the clinical importance of MRI-detected lumbar facet joint inflammatory features as a potential mechanism of nociception and as a predictor of outcomes following injections or other therapies.

Contrast flow in CT-guided lumbar interlaminar epidural steroid injections: does needle position effect the laterality of contrast flow?

PURPOSE: To evaluate the effect of needle position on the laterality of contrast flow in CT-guided lumbar interlaminar epidural steroid injections. MATERIALS AND METHODS: A retrospective review of consecutive CT-guided interlaminar lumbar epidural steroid injections was performed. The terminal needle tip position (midline or lateral) and the laterality of epidural contrast were evaluated by two readers. Contrast flow pattern was classified as ipsilateral to needle trajectory, bilateral, or contralateral. Bilateral flow was further divided into asymmetric, symmetrical, or asymmetric to the contralateral side. Inter-reader agreement was calculated with the kappa statistic. The relationship of needle position to contrast laterality was calculated with the chi statistic. Pain scores were compared for bilateral and unilateral flows with a two-tailed T test for independent means. RESULTS: A total of 250 injections were included in 204 patients, with an age range of 24 to 93 years. The most commonly injected level (145/250) was L4-L5. Agreement between the two readers was almost perfect and substantial (kappa 0.751-0.880). The majority of injections (154/250) demonstrated contrast flow ipsilateral to the needle trajectory, 90/250 demonstrated bilateral flow, and 6/250 had contralateral flow. Of the 90 cases with bilateral flow, 80% were performed with a midline terminal needle position (p < 0.001). There was no difference in immediate post-procedure pain scores between patients with ipsilateral or bilateral contrast flow. CONCLUSION: For interlaminar epidural steroid injections, a midline terminal needle tip position has a greater probability of producing bilateral contrast flow compared to a lateral terminal needle tip position.

Deep learning discrimination of rheumatoid arthritis from osteoarthritis on hand radiography.

PURPOSE: To develop a deep learning model to distinguish rheumatoid arthritis (RA) from osteoarthritis (OA) using hand radiographs and to evaluate the effects of changing pretraining and training parameters on model performance. MATERIALS AND METHODS: A convolutional neural network was retrospectively trained on 9714 hand radiograph exams from 8387 patients obtained from 2017 to 2021 at seven hospitals within an integrated healthcare network. Performance was assessed using an independent test set of 250 exams from 146 patients. Binary discriminatory capacity (no arthritis versus arthritis; RA versus not RA) and three-way classification (no arthritis versus OA versus RA) were evaluated. The effects of additional pretraining using musculoskeletal radiographs, using all views as opposed to only the posteroanterior view, and varying image resolution on model performance were also investigated. Area under the receiver operating characteristic curve (AUC) and Cohen's kappa coefficient were used to evaluate diagnostic performance. RESULTS: For no arthritis versus arthritis, the model achieved an AUC of 0.975 (95% CI: 0.957, 0.989). For RA versus not RA, the model achieved an AUC of 0.955 (95% CI: 0.919, 0.983). For three-way classification, the model achieved a kappa of 0.806 (95% CI: 0.742, 0.866) and accuracy of 87.2% (95% CI: 83.2%, 91.2%) on the test set. Increasing image resolution increased performance up to 1024 × 1024 pixels. Additional pretraining on musculoskeletal radiographs and using all views did not significantly affect performance. CONCLUSION: A deep learning model can be used to distinguish no arthritis, OA, and RA on hand radiographs with high performance.

Comprehensive Grading System of Inflammatory Features of the Lumbar Facet Joints on Magnetic Resonance Imaging.

STUDY DESIGN: Retrospective. OBJECTIVE: We aimed to describe a magnetic resonance imaging (MRI)-based grading system of inflammatory features of the lumbar facet joints using an atlas and assess its reliability. SUMMARY OF BACKGROUND DATA: Chronic low back pain is often caused by facet joint arthropathy. Inflammatory features are often evident on MRI. While several grading systems of facet arthropathy have been described, there is scant data on the reliability of these systems, and none focus exclusively on inflammatory features. MATERIALS AND METHODS: We describe a grading system that assesses facet joint effusion, bone marrow edema, and soft tissue edema. Each feature was graded from 0 to 3 (facet edema) or 0 to 2 (bone marrow edema intensity and extent, soft tissue edema intensity and extent). Four spine experts graded MRIs of 50 subjects at the bilateral L3/4, L4/5, and L5/S1 levels. All subjects had symptomatic facet arthropathy and received therapeutic facet joint injections. We assessed the intra-reader and inter-reader reliability of each feature at each joint and summarized across all six joints. RESULTS: The mean age of subjects was 56 years (SD = 17), and 48% were female. The injections occurred at the L3/4 level in 12% of cases, at L4/5 in 88%, and at L5/S1 in 80% of cases. The intra-reader reliability kappa's for each feature ranged from 0.42 to 0.81. In contrast, the inter-reader reliability kappa values for each feature ranged from 0.37 to 0.54. CONCLUSION: MRI inflammatory features of the lumbar facet joints are often noted in patients with low back pain. The proposed grading system is reliable and could serve as a research tool for studies assessing the clinical relevance and prognostic value of these features.

Predictors of Outcomes After Lumbar Intra-Articular Facet Joint Injections and Medial Branch Blocks: A Scoping Review.

STUDY DESIGN: A scoping review. OBJECTIVE: We aimed to identify and describe the factors associated with the patient-reported response after lumbar intra-articular facet joint (FJ) injections or medial branch blocks (MBBs). SUMMARY OF BACKGROUND DATA: FJ osteoarthritis is among the most common causes of chronic low back pain. Management often includes FJ intra-articular injection and MBBs (which may be followed by radiofrequency ablation of the nerves innervating these joints). However, the success of these approaches is variable, prompting interest in identifying patient characteristics (imaging features, clinical signs, and among others) associated with response to these types of facet injections. MATERIALS AND METHODS: We performed a literature search on factors associated with patient-reported outcomes after lumbar FJ intra-articular injections or MBBs for patients with low back pain published in English or Spanish between 2000 and 2023. We excluded duplicate papers that did not describe factors associated with outcomes or those describing other interventions. We collected data on the association of these factors with patient-reported outcomes. RESULTS: Thirty-seven studies met the inclusion criteria and were analyzed. These studies evaluated factors, such as age, depression, and single photon emission computed tomography (SPECT), and among variables. Age and imaging findings of facet arthropathy were the most frequently described factors. Imaging findings of FJ arthropathy and positive SPECT were often associated with positive results after intra-articular FJ injections or MBBs. In contrast, younger age and smoking were frequently associated with less favorable clinical outcomes. CONCLUSION: Numerous factors were considered in the 37 studies included in this review. Imaging findings of facet arthropathy, duration of pain, and positive SPECT were consistently associated with favorable results after facet interventions.

Awareness of interventional radiology and image guided musculoskeletal interventions among orthopaedic surgeons, rheumatologists, and physiatrists: A multi-site analysis.

PURPOSE: Evaluate physicians who treat musculoskeletal (MSK) disorders in their knowledge of image-guided MSK interventions, and identify areas that could benefit from education. MATERIALS AND METHODS: A 17-question survey was distributed to orthopaedic surgeons, physiatrists, and rheumatologists in the 14-hospital health system. It inquired about demographics, practice environment, awareness of interventional radiology (IR) and MSK radiology (MSKR) training, referral patterns, and knowledge of image-guided MSK interventions. RESULTS: In total, 59 of 303 physicians completed the survey (41% orthopaedists, 35% physiatrists, and 24% rheumatologists). Most (93%) were attendings and 41% were female. A minority of survey respondents (17%) recognized the designation of IR as a distinct specialty of medicine per the American Board of Medical Specialties, in contrast to MSKR, which is not designated as a distinct specialty. When queried about IR procedures not under investigation, 24% selected genicular artery embolization and 31% selected embolization for adhesive capsulitis. Barriers to referral were as follows: 21% of specialists performed the procedure, 17% listed electronic medical record challenges, 14% reported scheduling difficulty, 13% reported no barriers, 11% reported difficulty consulting, 11% referred to another specialty, 10% did not have enough knowledge of image guided procedures, and 3% reported the procedure is not performed by IR or MSKR. CONCLUSIONS: Survey data reveal a knowledge gap among surveyed physicians regarding IR as a specialty as well as areas of IR research in MSK disorders. Findings suggest areas where referring physicians can be educated and identify barriers to referral.

Genicular Artery Embolization as a Treatment for Osteoarthritis Related Knee Pain: A Systematic Review and Meta-analysis.

OBJECTIVE: Genicular artery embolization (GAE) is a minimally invasive therapy for symptomatic osteoarthritis (OA) in patients with knee pain refractory to conservative management. The purpose of this study was to evaluate evidence on the effectiveness of GAE for OA related knee pain as part of a systematic review and meta-analysis. MATERIALS AND METHODS: Using Embase, PubMed, and Web of Science, a systematic review was performed to identify studies evaluating treatment of knee OA with GAE. The primary outcome measure was change in pain scale score at 6 months. A Hedge's g was computed as a measure of effect size, selecting Visual Analog Scale (VAS) first if available and Knee Injury and Osteoarthritis Outcome Score and Western Ontario and McMaster Universities Osteoarthritis Index if VAS was not available. RESULTS: After screening titles, abstracts, and the full text, 10 studies met inclusion criteria. A total of 351 treated knees were included. Patients who underwent GAE demonstrated declines in VAS pain scores at 1 month {- 34 points [95% CI (- 43.8, - 24.6)], 3 months {- 30 points [95% CI (- 41.7, - 19.2)], 6 months {- 41 points [95% CI (- 54.0, - 27.2)], and 12 months {- 37 points [95% CI (- 55.0, - 18.1)]. Hedges' g from baseline to 1, 3, 6, and 12 months, was {- 1.3 [95% CI (- 1.6, - 0.97)]}, {- 1.2 [95% CI (- 1.54, - 0.84)]}, {- 1.4 [95% CI (- 2.1, - 0.8)]}, and {- 1.25 [95% CI (- 2.0, - 0.6)]}, respectively. CONCLUSION: GAE provides durable reductions in pain scores for patients suffering with mild, moderate, and severe OA.

Grading Systems of Lumbar Facet Joint Inflammatory Changes on Magnetic Resonance Imaging: A Scoping Review.

STUDY DESIGN: A scoping review. OBJECTIVE: We aimed to identify and characterize grading systems of the inflammatory features of the lumbar facet joints (FJs) noted on magnetic resonance imaging and summarize their reliability. SUMMARY OF BACKGROUND DATA: Chronic low back pain is one of the most common causes of disability worldwide and is frequently accompanied by FJ osteoarthritis. Inflammatory changes in the lumbar FJs are commonly noted in imaging studies of patients with FJ osteoarthritis and low back pain. Several grading systems for these inflammatory changes have been developed. However, these grading system's features and reliability have yet to be reviewed. MATERIALS AND METHODS: We performed a literature search of studies reporting grading systems for FJ inflammatory changes published in English or Spanish between 1985 and 2022. We collected data on reported interreader reliability measures of each grading system. Finally, we compared the features of inflammation described by each system. RESULTS: Six studies met the inclusion criteria and were used in our analysis. Features commonly graded in these systems are the hyperintensity signal noted within the FJ, bone marrow edema, and the extent of the soft-tissue edema surrounding the FJs. We found that the interreader reliability measures ranged from 0.56 to 0.96. CONCLUSIONS: Only 6 studies have reported methods for documenting inflammation in the FJs. Studies varied in the precise tissues and phenomena included in the grading systems. However, the systems were generally reliable. Future studies should document the reliability of these methods when independent investigators are not involved in developing the classification schemes. Further work might combine one or more of these measures to establish a standard and reliable grading system for inflammatory changes in the FJs, including signal intensity within the joint, bone marrow edema, and soft-tissue inflammation.

A Retrospective Analysis of Sternal Lesions Detected on Breast MRI in Patients Without History of Cancer.

OBJECTIVE: To determine the imaging characteristics and stability over time of sternal lesions identified on breast MRI in patients without history of cancer. METHODS: An IRB-approved retrospective analysis of all breast MRIs performed at our institution from September 1, 2017 to December 1, 2021 that included one of several key words related to the sternum. Studies with history of non-dermatologic malignancy including breast cancer, absence of a true sternal lesion, or presence of symptoms during the examination were excluded. Imaging was reviewed for size, distribution, signal characteristics, and presence of contrast enhancement, perilesional edema, periosteal edema, or intralesional fat. Available comparison imaging, clinical history, and follow-up recommendations were reviewed. Descriptive statistics were used to summarize lesion data. RESULTS: Of 60 lesions included from 60 patients, 40 lesions with more than two years of comparison imaging were either stable or decreased in size and none demonstrated change in signal characteristics. The majority of these presumed benign lesions demonstrated hypointense signal on T1-weighted sequences (21/40, 52.5%), hyperintense signal on fluid-sensitive sequences (33/40, 82.5%), contrast enhancement (32/40, 80.0%), and absence of clear intralesional fat (29/40, 72.5%). One patient who did not have comparison imaging was diagnosed with malignancy (multiple myeloma) eight months following their MRI. This lesion demonstrated uniquely diffuse and heterogeneous enhancement but did not undergo biopsy. CONCLUSION: Sternal lesions in women without history of non-dermatologic malignancy have a very low likelihood of malignancy. Common imaging characteristics of the presumed benign lesions can inform imaging recommendations when incidental sternal lesions are discovered.

Diagnostic accuracy of pelvic radiographs for the detection of traumatic pelvic fractures in the elderly.

PURPOSE: Prompt identification of traumatic pelvic fractures in the elderly is critical to guide clinical management; however, the accuracy of pelvic radiographs is often compromised by multiple factors. The purpose of this study is to examine the diagnostic accuracy of radiographs for the detection of pelvic fractures, with CT as the standard of reference. METHODS: A retrospective review was performed of patients ≥ 65 years with traumatic pelvic fractures evaluated with both pelvic radiography and computed tomography (CT) from May 2016 to October 2019. Pelvic fractures were classified into fractures of the pubis, ilium, ischium, sacrum, and acetabulum. All pelvic radiographs were independently reviewed by two emergency radiologists. Original CT reports were utilized for the reference standard. RESULTS: 177 patients were included, with a total of 555 fractures. The mean age was 81 years and 68% were female. The most common mechanism of injury was fall (62%), followed by motor vehicle accidents (18%). The most fractured bone was the pubis (314/555 fractures). Global pooled sensitivity for pelvic radiographs in detecting pelvic fractures compared to CT was 48%, with a specificity of 93%. Sensitivity for the detection of pelvic fractures is classified by the following types: pubis 61%, acetabulum 60%, ilium 41%, sacrum 20%, and ischium 17%. Eighteen patients (10%) required surgical fixation. Mortality was 8%. CONCLUSION: Pelvic radiographs have low sensitivity in detecting traumatic pelvic fractures. These radiographically occult fractures may be clinically significant as a cause of long-term pain and may require orthopedic consultation and possible surgical management.

Musculoskeletal Trauma and Infection.

MR is often the most definitive imaging for assessment of musculoskeletal trauma and infection. Although it is not possible to address all the intricacies of these complex topics in a single article, this review will attempt to provide a useful toolbox of skills by discussing several common clinical scenarios faced by emergency radiologists in interpretation of adult trauma and infection. These scenarios include MR assessment of hip and pelvic fracture, traumatic soft tissue injuries, septic arthritis, soft tissue infection, and osteomyelitis.

Radiation dose of fluoroscopy-guided versus ultralow-dose CT-fluoroscopy-guided lumbar spine epidural steroid injections.

OBJECTIVE: Compare radiation dose of lumbar spine epidural steroid injections (ESIs) performed under fluoroscopy guidance and ultralow-dose CT-fluoroscopy guidance. MATERIALS AND METHODS: Retrospective review of consecutive lumbar ESIs performed using fluoroscopy, between May 2017 and April 2019, and using ultralow-dose CT-fluoroscopy, between August 2019 and February 2021, was performed. Ultralow-dose CT-fluoroscopy technique omits a planning CT scan, utilizes CT-fluoroscopy, and minimizes radiation dose parameters. Patient characteristics (age, sex, height, weight, body mass index (BMI)), procedural characteristics (anatomic level, type of ESI, procedure time, pain reduction, complications, trainee participation), and radiation dose were compared. Chi-square tests and two-sample t-tests were performed for statistical analysis. RESULTS: One hundred and forty-seven patients (mean age 55.8 ± 16.7; 85 women) underwent ESIs using fluoroscopy. Sixty-six patients (mean age 60.9 ± 16.7; 33 women) underwent ESIs using ultralow-dose CT-fluoroscopy. The effective dose for the fluoroscopy group was 0.30 mSv ± 0.34, compared to 0.15 mSV ± 0.11 for ultralow-dose CT-fluoroscopy (p < 0.001). The average age in the CT-fluoroscopy group was older (p = 0.04), and there was more trainee participation in the fluoroscopy group (p < 0.001); otherwise there was no statistically significant difference in patient or procedural characteristics between the conventional fluoroscopy group and the ultralow-dose CT-fluoroscopy group. There was no statistically significant difference in immediate post-procedure pain reduction between the groups (p = 0.16). Four intrathecal injections occurred only in the fluoroscopy group, though this difference was not significant (p = 0.18). CONCLUSION: Ultralow-dose CT-fluoroscopy technique for image-guided lumbar spine ESIs can lower radiation dose compared to fluoroscopy-guided technique.

Standardized Classification of Lumbar Spine Degeneration on Magnetic Resonance Imaging Reduces Intra- and Inter-subspecialty Variability.

BACKGROUND AND PURPOSE: To determine the efficacy of standardized definitions of degenerative change in reducing variability in interpretation of lumbar spine magnetic resonance imaging within and between groups of subspecialty-trained neuroradiologists (NR) and musculoskeletal radiologists (MSK). MATERIALS AND METHODS: Six radiologists, three from both NR and MSK groups were trained on a standardized classification system of degenerative change. After an 11-month washout period, they independently re-interpreted fifty exams at the L4-L5 and L5-S1 levels. Responses were converted to a six-point ordinal scale for the assessment of neural foraminal stenosis and spinal canal stenosis (SCS), three-point scale for lateral recess stenosis, and four-point scale for facet osteoarthritis (FO). Intra-subspecialty and inter-subspecialty analysis was performed using the weighted Cohen's kappa with a binary matrix of all reader pairs. RESULTS: Inter-subspecialty agreement improved from k=0.527 (moderate) to k=0.602 (substantial) for neural foraminal stenosis, from k=0.540 (moderate) to k=0.652 (substantial) for SCS, from k=0.0818 (slight) to k=0.337 (fair) for lateral recess stenosis, and from k=0.176 (slight) to k=0.495 (moderate) for FO. The NR group demonstrated improved intra-subspecialty agreement for the assessment of SCS, from k=0.368 (fair) to k=0.638 (substantial). The MSK group demonstrated improved intra-subspecialty agreement for the assessment of FO, from k=0.134 (slight) to k=0.413 (moderate). Intra-subspecialty agreement was similar for other parameters before and after training. CONCLUSIONS: As result of the standardized definitions training, the NR and MSK groups each improved in one of the four parameters, while inter-subspecialty variability improved in all four parameters. These definitions may be useful in clinical practice across radiology subspecialties.

ACR Appropriateness Criteria® Inflammatory Back Pain: Known or Suspected Axial Spondyloarthritis: 2021 Update.

Inflammatory back pain is a hallmark feature of axial spondyloarthritis, a heterogeneous group of inflammatory disorders which affects the sacroiliac joints and spine. Imaging plays a key role in diagnosis of this disease and in facilitating appropriate treatment. This document provides evidence-based recommendations on the appropriate use of imaging studies during multiple stages of the clinical evaluation of patients with suspected or known axial spondyloarthritis. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Simplified Universal Grading of Lumbar Spine MRI Degenerative Findings: Inter-Reader Agreement of Non-Radiologist Spine Experts.

OBJECTIVE: 1) To describe a simplified multidisciplinary grading system for the most clinically relevant lumbar spine degenerative changes. 2) To measure the inter-reader variability among non-radiologist spine experts in their use of the classification system for interpretation of a consecutive series of lumbar spine magnetic resonance imaging (MRI) examinations. METHODS: ATS multidisciplinary and collaborative standardized grading of spinal stenosis, foraminal stenosis, lateral recess stenosis, and facet arthropathy was developed. Our institution's picture archiving and communication system was searched for 50 consecutive patients who underwent non-contrast MRI of the lumbar spine for chronic back pain, radiculopathy, or symptoms of spinal stenosis. Three fellowship-trained spine subspecialists from neurosurgery, orthopedic surgery, and physiatry interpreted the 50 exams using the classification at the L4-L5 and L5-S1 levels. Inter-reader agreement was assessed with Cohen's kappa coefficient. RESULTS: For spinal stenosis, the readers demonstrated substantial agreement (κ = 0.702). For foraminal stenosis and facet arthropathy, the three readers demonstrated moderate agreement (κ = 0.544, and 0.557, respectively). For lateral recess stenosis, there was fair agreement (κ = 0.323). CONCLUSIONS: A simplified universal grading system of lumbar spine MRI degenerative findings is newly described. Use of this multidisciplinary grading system in the assessment of clinically relevant degenerative changes revealed moderate to substantial agreement among non-radiologist spine physicians. This standardized grading system could serve as a foundation for interdisciplinary communication.

Imaging of meniscal allograft transplantation: what the radiologist needs to know.

Meniscal allograft transplantation is an emerging surgical option for younger patients with symptomatic meniscal deficiency, which aims to restore anatomic biomechanics and load distribution in the knee joint, and by so doing to potentially delay accelerated osteoarthritis. In this review article, we summarize the structure and biomechanics of the native meniscus, describe indications and procedure technique for meniscal allograft transplantation, and demonstrate the spectrum of expected postoperative imaging and role of imaging to identify potential complications.

Do non-weight-bearing knee radiographs for chronic knee pain result in increased follow-up imaging?

OBJECTIVE: While weight-bearing radiographs are considered the optimal method for evaluation of joint spaces in osteoarthritis, non-weight-bearing radiographs are often performed. The purpose of this study is to evaluate the rate of follow-up radiographs in patients receiving non-weight-bearing radiographs for chronic knee pain in the outpatient setting, compared with patients receiving weight-bearing radiographs. MATERIALS AND METHODS: Consecutive patients who received non-weight-bearing knee radiographs for chronic knee pain between January 1, 2018, and June 15, 2019, were included. Exclusion criteria included trauma, concern for infection or tumor, and post-surgical radiographs. An age- and sex-matched control group of 100 patients who received weight-bearing knee radiographs was compiled. The proportion of follow-up radiographs within 1 year was compared between the study and control groups with chi-squared tests. RESULTS: Four hundred non-weight-bearing knee radiographic examinations were included. There were 74/400 (18.5%) follow-up radiographs within 12 months. All follow-up radiographs were weight-bearing. In the control group, 4/100 (4%) had follow-up weight-bearing radiographs within 1 year (p < 0.001). CONCLUSION: Outpatients who underwent non-weight-bearing knee radiographs for chronic pain had a higher frequency of repeat imaging than those who initially underwent weight-bearing knee radiographs. These results suggest that non-weight-bearing knee radiographs are of lower clinical utility compared with weight-bearing radiographs.

Clinical utility of a focused hip MRI for assessing suspected hip fracture in the emergency department.

PURPOSE: A focused hip MRI (FHMR) for the detection of radiographically occult hip fractures was implemented in our emergency department (ED) in 2013. The goal of this study was to assess the clinical utility of this protocol. METHODS: We retrospectively reviewed radiology reports of 262 unique patients who underwent 263 FHMR (coronal T1, coronal STIR, axial T2 fat saturated) for suspected hip fracture in the ED from October 2013 to March 2020. Electronic medical records were reviewed for the ED course, follow-up imaging, and clinical management within 90 days. RESULTS: Seventy-one patients had one or more fractures identified by FHMR: one-third had proximal femoral fractures; two-third had pelvic fractures. Of these 71 patients, 53 (74%) had radiographically occult fractures, including 14 (20%) with occult proximal femoral fractures; 4 patients had fractures occult on CT. Nineteen patients with a suspected fracture on radiography were found to have no fracture on FHMR. Four fractures not reported on FHMR were later seen on follow-up imaging: these included 1 isolated greater trochanter, 1 additional ischial tuberosity, 1 additional superior pubic ramus, and 1 additional sacrum. All four fractures were treated non-operatively. Muscle/tendon injury was the most common type of injury, seen in 50% (130/262) patients with the most commonly torn tendons being the hamstring (44%; 15/34) followed by gluteus medius tendon (18%; 6/34). A full-hip or pelvis MRI was done after FHMR in only 5 patients, primarily for the purpose of better characterizing findings already identified on FHMR (2 for fracture, 2 for tendon injury, 1 for soft tissue metastasis). Only one of these five studies provided new information: ruling out a previously questioned fracture. Clinical management of the vast majority of patients was based solely on findings from the FHMR. CONCLUSIONS: FHMR offers reliable identification of radiographically occult hip fractures and muscle/tendon injuries. The protocol is well trusted in guiding patient management in our ED.