The value of injectable viscoelastic supplements for joints.

Intra-articular viscoelastic supplements are commonly administered by musculoskeletal radiologists for the treatment of symptomatic osteoarthritis (OA). This article provides an overview of the putative mechanism of action of the agents, a brief review of the evidence base underlying the practice, a commentary on some of the major society guidelines regarding the treatment, and a description of the adverse events that are associated with intra-articular hyaluronic acid administration.

Complications in image-guided musculoskeletal injections.

OBJECTIVE: To establish the incidence and define the nature of complications occurring following image-guided musculoskeletal injections at our institution. MATERIALS AND METHODS: All patients undergoing image-guided musculoskeletal injection during the study period (16/3/2016 to 24/01/2020) were included. Departmental records were reviewed to identify all patients describing possible complications following injection, what therapy was required (if any) and what the outcome was. No patients were excluded. Complications were classified as minor or major. Injections were categorised as follows: cervical spine, lumbar facet joint, lumbar nerve root, caudal epidural and 'other'. The complication rate for each individual category of procedure was compared with the combined complication rate for all other categories by constructing contingency tables and using Fisher's exact test. RESULTS: A total of 8226 patients underwent image-guided musculoskeletal injections within the study period. Exactly 100 patients were identified as having reported a complication, producing an overall complication rate of 1.2%. One complication was categorised as 'major', with the patient requiring expedited surgery. The remainder (99 patients) were categorised as having experienced minor complications. The incidence of complications after 'other' injections was significantly greater than for other categories of injection (1.86%, p = 0.028). There was no significant difference in the complication rate for cervical spine (0.93%, p = 0.257), lumbar nerve root (0.85%, p = 0.401), lumbar facet joint (0.67%, p = 0.326) or caudal epidural (1.29%, p = 0.687) injections. 'Other' injections were subsequently further sub-categorised by anatomical site and imaging modality used. Glenohumeral (2.97%, p = 0.0361) and sacro-iliac (3.51%, p = 0.0498) joint injections were associated with a significantly increased risk of complications. There was no difference in the incidence of complications with fluoroscopic or ultrasound guidance. CONCLUSION: In conclusion, image-guided musculoskeletal injections are safe and well-tolerated procedures. Complications are rare, occurring in just 1.2% of patients. 99% of complications are minor, either not requiring intervention or resolving with simple supportive treatment.

Gaelic Sport Injuries.

The Gaelic sports of hurling and football, native to Ireland, are increasing in popularity worldwide. The injury profile of these sports requires multidisciplinary management by sports physicians, orthopaedic surgeons, and musculoskeletal (MSK) radiologists, among others. Advances in imaging modalities and interventional techniques have aided the diagnosis and treatment of sport injuries. In this article, we review the literature and our own institutional experience to describe common injury patterns identified in Gaelic games athletes, their main imaging features and relevant therapeutic interventions. We discuss the increasing prevalence of imaging services at sporting events and the central role of MSK radiologists in sports injury management.

Whole-body MRI of bone marrow: A review.

Technical advances in the last two decades have allowed rapid, high-resolution whole-body magnetic resonance imaging (WBMRI). MRI allows unparalleled visualization and detail in the imaging of bone marrow and surrounding soft tissues. The properties of nuclear magnetic resonance allow superb characterization of bone marrow constituents. WBMRI allows superb characterization of the different types of bone marrow and their natural evolution during the life cycle. Diffusion-weighted WBMRI is an exciting development that adds functional information to anatomical detail. The mainstay of WBMRI for bone marrow abnormalities to date has centered upon staging multiple myeloma and other hematologic bone marrow conditions, and as a valuable tool in quantifying skeletal metastases. Increasingly, WBMRI is being utilized in a variety of additional malignant and nonmalignant conditions. Due to the absence of ionizing radiation, WBMRI represents a valuable screening tool in areas such as malignant transformation in hereditary multifocal exostoses or for the development of ischemic marrow insult in at-risk patients. An additional novel area of use includes postmortem WBMRI for characterization of skeletal injuries. This article provides a state-of-the-art and current review of WBMRI of the bone marrow and highlights potential future areas of development. Level of Evidence: 5 Technical Efficacy Stage: 3 J. MAGN. RESON. IMAGING 2019. J. Magn. Reson. Imaging 2019;50:1687-1701.

Perylene Bisimide Dyes with up to Five Independently Introduced Substituents: Controlling the Functionalization Pattern and Photophysical Properties Using Regiospecific Bay Substitution.

We report herein a versatile and user-friendly synthetic methodology based on sequential functionalization that enables the synthesis of previously unknown perylene bisimide (PBI) dyes with up to five different substituents attached to the perylene core (e.g., compound 15). The key to the success of our strategy is a highly efficient regiospecific 7-mono- and 7,12-di-phenoxy bay substitution at the "imide-activated" 7- and 12-bay positions of 1,6,7,12-tetrachloroperylene monoimide diester 1. The facile subsequent conversion of the diester groups into an imide group resulted in novel PBIs (e.g., compound 14) with two phenoxy substituents specifically at the 7- and 12-bay positions. This conversion led to the activation of C-1 and C-6 bay positions, and thereafter, the remaining two chlorine atoms were substituted to obtain tetraphenoxy-PBI (compound 15) that has two different imide and three different bay substituents. The methodology provides excellent control over the functionalization pattern, which enables the synthesis of various regioisomeric pairs bearing the same bay substituents. Another important feature of this strategy is the high sensitivity of HOMO-LUMO energies and photoinduced charge transfer toward sequential functionalization. As a result, systematic fluorescence on-off switching has been demonstrated upon subsequent substitution with the electron-donating 4-methoxyphenoxy substituent.

Training in Musculoskeletal Radiology in Europe: Philosophy, Challenges, and Practical Implementation.

This article provides an overview of the philosophy, mechanisms, and difficulties involved in the establishment of integrated training programs in medicine, radiology, and specifically musculoskeletal radiology across the European Union.

Role of Musculoskeletal Radiology in Modern Sports Medicine.

Musculoskeletal radiology's role in the recent and continued evolution of sports medicine is an exciting and expanding one. In this article we explore a variety of the ways that musculoskeletal radiology contributes to current practices in modern sports medicine, discussing advances across a variety of imaging modalities in the care of both elite athletes and so-called weekend warriors. We describe the technical and ethical factors pertaining to image-guided therapeutic intervention in athletes and speculate on the potential for future developments in the role of imaging in deciding when an athlete may return to participation. We also explore the recent shift to the delivery of imaging facilities at sporting events and in stadiums.

Therapeutic Intervention in Musculoskeletal Radiology: Current Practice and Future Directions.

Over the last several decades, the volume and range of therapeutic musculoskeletal (MSK) interventions that radiologists can offer their patients has dramatically increased. With new materials and improving imaging modalities, as well as significant investment in research, the field of MSK interventional radiologic intervention will likely continue to expand. In this article, we summarize the range of interventions currently available to the MSK radiologist. We also seek to explore new and emerging techniques that may become commonplace in the near future while considering the challenges that may lie ahead in the field of MSK radiology.

Injectable Viscoelastic Supplements: A Review for Radiologists.

OBJECTIVE: Hyaluronic acid (HA) is increasingly used by musculoskeletal radiologists in the treatment of osteoarthritis (OA). Although the evidence base for its efficacy is controversial, it remains in common use. With initial evidence suggesting its efficacy in the knee, it is now offered for treating OA of the hip, ankle, and elsewhere. CONCLUSION: HA is available in a wide variety of preparations, which may vary in concentration and chemical composition. Clinicians offering intraarticular HA injection should be familiar with the common preparations available and the principal differences between them, its mechanism of action, and the profile of adverse effects associated with its use.

Sports-Related Groin Pain Secondary to Symphysis Pubis Disorders: Correlation Between MRI Findings and Outcome After Fluoroscopy-Guided Injection of Steroid and Local Anesthetic.

OBJECTIVE: The objective of our study was to correlate patterns of injury on preprocedural MRI with outcome after targeted fluoroscopy-guided steroid and local anesthetic injection of the symphysis pubis and its muscular attachments in a group of athletes with chronic groin pain. MATERIALS AND METHODS: Forty-five patients with chronic sports-related groin pain underwent MRI of the pelvis and a targeted fluoroscopy-guided symphyseal corticosteroid and local anesthetic injection. Preprocedural MRI was reviewed. The presence or absence of a "superior cleft" sign (i.e., rectus abdominis-adductor longus attachment microtearing), "secondary cleft" sign (i.e., short adductor [gracilis, adductor brevis, and pectineus muscles] attachment microtearing), osteitis pubis, and extrasymphyseal pelvic abnormalities was recorded. Patients were followed up a mean time of 23 months after the procedure, and outcome was recorded. Correlation was made between preprocedural MRI findings and outcome. RESULTS: Forty-two percent of the patients had an isolated superior cleft sign, 7% had an isolated secondary cleft sign, and 11% had isolated osteitis pubis. Thirty-one percent of patients had a more complex injury, and 9% had a normal symphysis pubis. Overall, 89% of the patients experienced an improvement in symptoms. The response was sustained after a minimum of 6 months in 58% of the patients. The presence of the superior cleft sign was more frequently associated with a complete recovery. CONCLUSION: Fluoroscopy-guided corticosteroid symphyseal injection is a safe and effective treatment of sports-related groin pain. It is more frequently associated with a complete recovery in patients who display an isolated superior cleft sign on MRI. MRI not only is useful in characterizing groin injuries but also may be helpful in predicting response to therapeutic injection.

MR epidurography: distribution of injectate at caudal epidural injection.

OBJECTIVE: To (a) evaluate the feasibility of MR epidurography (MRE) and (b) assess the distribution of injectate using two different volumes at caudal epidural steroid injection. MATERIALS AND METHODS: Twenty patients who were referred with symptomatic low back pain for caudal epidural steroid injection were assigned to have either 10 ml (9/20) or 20 ml (11/20) of injectate administered. Gadolinium was included in the injection. The patients proceeded to MRI where sagittal and coronal T1-weighted fat-saturated sequences were acquired and reviewed in the mid-sagittal and right and left parasagittal views at the level of the exit foramina. RESULTS: Gadolinium was observed at or above the L3/4 disc level in all 11 patients who received 20 ml (100 %), compared with only five of nine patients who received 10 ml (56 %). Injectate was seen to the L4 nerve root level in all 11 patients who received 20 ml (100 %) but only four out of nine patients who received 10 ml (44 %), not even reaching the L5 nerve root level in four further of these nine patients (44 %). Overall, there was a trend to visualize gadolinium at higher levels of the epidural space with higher volumes injected. CONCLUSIONS: Firstly, MR epidurography is a safe technique that allows excellent visualization of the distribution of gadolinium in the epidural space following injection via the caudal hiatus. Secondly, a volume of 10 ml is unlikely to treat L5/S1 disease in almost half of patients at caudal epidural steroid injection and at least 20 ml of injectate is likely required for any medication to reach the desired level.

Percutaneous image-guided treatment of mucoid degeneration of the ACL in advanced knee osteoarthritis-Preliminary observations.

OBJECTIVES: To describe the percutaneous image-guided treatment of mucoid degeneration of the ACL causing deep knee pain on flexion in patients with advanced knee osteoarthritis. METHODS: Five patients with mucoid degeneration of the ACL complicating knee osteoarthritis underwent percutaneous image-guided steroid bupivacaine ACL sleeve injections over a 3-year period. RESULTS: There were four males and one female of mean age 54 (range 48-59 years). Each patient had Kellgren and Lawrence grade 4 medial compartment knee osteoarthritis with coexistent mucoid degeneration of the ACL sleeve. Each patient complained of deep knee pain on flexion as a dominant symptom. Each patient underwent image-guided (CT or ultrasound) steroid bupivacaine injection of the ACL sleeve resulting in symptom resolution and improved mobility for a mean duration of 8 months, (range 6-15 months.) CONCLUSION: Mucoid degeneration of the ACL should be sought in patients with osteoarthritis presenting with deep knee pain on flexion. Image-guided ACL sleeve injection in affected patients may result in symptom resolution and potential deferral of planned knee replacement surgery. ADVANCES IN KNOWLEDGE: Emphasises Image guided percutaneous treatment of Mucoid degeneration of ACL in patients with knee osteoarthritis.

Are brake response times altered post CT-guided cervical spine nerve root injections?

OBJECTIVES: To assess if brake response times are altered pre and post CT-guided cervical spine nerve root injections. METHODS: Brake response times were assessed before and after CT-guided cervical spine nerve root injections in a cohort of patients. The average of 3 brake response times was recorded before and 30 min after injection. Statistical analysis was performed using GraphPad. A paired Student t-test was used to compare the times before and after the injections. RESULTS: Forty patients were included in this study. The mean age was 55 years. There were 17 male and 23 female patients. There was no significant difference in the mean pre and post CT-guided cervical spine nerve root injection brake response times; 0.94 s (range 0.4-1.2 s) and 0.93 s (range 0.5-1.25 s), respectively (P = .77). CONCLUSIONS: Brake response time did not significantly differ pre and 30 min post CT-guided cervical spine nerve root injections. ADVANCES IN KNOWLEDGE: To the authors' best knowledge, there are no current studies assessing brake response times post CT-guided cervical spine nerve root injections. While driving safety cannot be proven by a single metric, it is a useful study in demonstrating that this is not inhibited in a cohort of patients.

Comparison of 3T MR arthrography and 3T MRI in intra-articular hip pathology: a cost-analysis.

BACKGROUND: MR arthrography (MRA) has previously been the radiological gold standard for investigating labral and chondral lesions of the hip joint. In recent years, 3T MRI has demonstrated comparable accuracy, being adopted as the first-line imaging investigation in many institutions. AIMS: We compare the associated increased cost and radiation dose of the fluoroscopic component of the MRA compared to MRI. METHODS: In this retrospective review over 2 years, 120 patients (mean age 27.3 years ± 13.2, range 8-67) underwent 3T MRA or non-contrast 3T MRI. Three musculoskeletal radiologists reported the data independently. Primary objectives included cost-comparison between each and radiation dose of the fluoroscopic component of the MRA. Secondary objectives included comparing detection of pathology involving the acetabular labrum, femoral cartilage, and acetabular cartilage. RESULTS: Then, 58 (48%) underwent 3T MRA and 62 (52%) patients underwent 3T MRI. The added cost of the fluoroscopic injection prior to MRA was €116.31/patient, equating to €7211.22 savings/year. MRA was associated with a small radiation dose of 0.003 mSv. CONCLUSIONS: Transitioning from 3T MRA to 3T MRI in the investigation of intra-articular hip pathology increases cost savings and reduces radiation dose.

"Superior cleft sign" as a marker of rectus abdominus/adductor longus tear in patients with suspected sportsman's hernia.

OBJECTIVE: We describe a new imaging sign, the "superior cleft sign", identified at both symphysography and MRI, which should be used as a marker of rectus abdominis/adductor longus attachment tearing. MATERIALS AND METHODS: A study population of 25 patients presenting with clinically suspected sportsman's hernia, who had undergone both symphysography and MRI of the groin were included for study. In each case, images were reviewed to determine the presence of a superior cleft, secondary cleft, and or both abnormalities. RESULTS: Images of all patients complaining of groin crease discomfort similar to sportsman's hernia revealed the presence of a superior cleft at the rectus abdominis/adductor longus attachment. This "superior cleft sign" correlated with the side of symptoms in each case, and, in contrast to the previously described secondary cleft along the inferior margin of the inferior pubic ramus, occurred parallel to the inferior margin of the superior pubic ramus. CONCLUSIONS: The presence of the "superior cleft sign" should be sought in addition to the previously described secondary cleft sign in sportspeople presenting with exercise-related groin pain or pubalgia. It should specifically be sought in patients referred with suspected sportsman's hernia.

Does MRI Knee in Those over 50 Years with Knee Pain in Osteoarthritis Alter Management? A Retrospective Review.

Knee osteoarthritis (OA) is a significant cause of pain and disability worldwide. Imaging provides diagnosis, prognostication, and follow-up. Radiographs are first line, useful, and inexpensive. Magnetic resonance imaging (MRI) can detect additional features not seen on radiograph, but it is of questionable usefulness in the management of knee OA. Our aim was to investigate the usefulness of MRI in the workup of knee OA and whether MRI alters management in knee OA. A retrospective review was performed of consecutive MRI knees performed for knee pain in those over 50 years. Clinical information and documentation of management plan pre- and post-MRI were collected. Assessment was made whether the MRI results influenced the final management plan. Of the 222 MRI knees included for study, the majority (62.2%) had not had a recent radiograph. OA was reported in 86.9% of radiographs and 89.6% of MRI. On MRI, the most prevalent finding was tearing/abnormality of the medial meniscus, seen in 47% of MRIs overall, increasing to all in severe OA. MRI assisted with management in 9.5% of all (21/222) patients, and changed management plans in 23% of those that had documented management plans prior to the MRI (6/26 patients). MRIs can guide tailored management in knee OA and are useful for surgical planning; however, they should only be ordered in certain cases, and a radiograph should always be performed first. MRI should be considered if symptoms are not explained by OA alone or the appropriate treatment option requires MRI.