Clinical Outcomes of Transcatheter Arterial Embolization for Adhesive Capsulitis Resistant to Conservative Treatment

Angioembolization in the management of joint pain: current concepts

Joint pain is a common complaint owing to its origin in inflammatory and degenerative joint diseases. Recent research has helped narrow down inadequate angiogenesis as one of the causes. Angioembolization has emerged as a treatment option for this condition when it is refractory to conservative treatment. This review describes angioembolization by elaborating on the mechanism, safety, efficacy, comparative analysis of treatment and the road ahead, in addition to summarizing the existing data on this treatment. The inferences from this review further consolidate transcatheter arterial embolization as one of the prime options for managing joint pain when it is refractory to conservative treatment and label it as one of the most exciting prospects. A limitation of this review is that most of the data were from open label case series or case reports.

Lipiodol Versus Imipenem/Cilastatin in Genicular Artery Embolization: A Retrospective Study on Safety and Clinical Success

PURPOSE

This study aims to evaluate the safety and effectiveness of genicular artery embolization (GAE) using lipiodol in comparison to imipenem/cilastatin (IPM-CS).

MATERIALS AND METHODS

This retrospective study screened patients who underwent GAE between January 2022 and February 2023 for inclusion. Clinical outcomes were assessed at 1, 3, and 6 months post-procedure using the Visual Analog Scale (VAS) for pain and the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) for pain, stiffness, functional capacity, and total scores. Technical and clinical success rates, complications, and patient-reported outcomes were assessed.

RESULTS

A total of 42 patients were included in the study, with 13 patients treated with lipiodol and 29 with IPM-CS for GAE. Transient skin discoloration was noted in 23.1% of lipiodol patients and 31% of the IPM-CS group (p = 0.722). One patient (7.6%) in the lipiodol group developed knee edema and erythema due to drug-induced vasculitis (p = 0.309). Clinical success rates in the lipiodol group were 76.9% at 1 month, consistent at 3 months, and 69.2% at 6 months. For the IPM-CS group, success rates were 89.7, 86.2, and 75.9%, respectively, with no significant differences (p = 0.353, p = 0.657, p = 0.713). The median percentage change in WOMAC stiffness scores for the lipiodol group at 1, 3, and 6 months post-GAE were - 25%, - 16.7%, and - 16.7%, respectively, while the IPM-CS group showed decreases of - 40%, - 50%, and - 50%. Significant differences were found between the groups at all time points (p = 0.017, p = 0.009, and p = 0.002, respectively).

CONCLUSION

Lipiodol shows comparable clinical success to IPM-CS in GAE.

Diagnostic Value of Superb Microvascular Imaging of the Rotator Cuff Interval for the Early Diagnosis of Frozen Shoulder

Purpose

To explore the early diagnostic value of superb microvascular imaging (SMI) features within the rotator cuff gap for frozen shoulder.

Patients and Methods

This prospective study enrolled patients with acute early-stage frozen shoulder seeking treatment at Zhabei Central Hospital in Jing'an District, Shanghai, between July 2021 and December 2022 were enrolled in this study. Healthy controls were collected in a 1:1 ratio from the same hospital's physical examination center. All participants underwent SMI and power Doppler ultrasound (PDUS) of the rotator cuff gap.

Results

The study included 79 patients with frozen shoulder and 77 healthy controls. Compared with the healthy control group, the patient group had a higher proportion of hypoechoic rotator cuff gap (81.0% vs 48.1%, P<0.001), a thicker coracohumeral ligament (2.60±1.01 vs 2.03±0.97, P<0.001), a thicker glenohumeral joint capsule (3.10±0.99 vs 2.46±1.17, P<0.001), and elevated blood grading using SMI (P<0.001) and PDUS (P=0.014). The highest area under the curve (AUC) was observed for SMI blood flow grading (AUC=0.824, 95% CI: 0.755-0.880, P<0.001), resulting in 82% sensitivity and 77% specificity when using a cutoff of 1. SMI blood flow grading was associated with external rotation <30° (P=0.007) and abduction <30° (P=0.013) but not with internal rotation <30° (P=0.630) or flexion <30° (P=0.562).

Conclusion

The grading of SMI blood flow may emerge as a valuable predictive indicator for the early stages of frozen shoulder. This simple ultrasound technique holds the potential to enhance the diagnostic process, enabling early initiation of treatment and potentially improving patient outcomes.

Transarterial microembolization for the management of refractory chronic joint pain in osteoarthritis

Osteoarthritis (OA) is a chronic degenerative disease significantly impacting both patient quality of life and socioeconomics. Traditional treatment options, including pharmacological and surgical interventions, are often limited. Advancements in our understanding of the pathological mechanisms behind OA indicate the involvement of pathological angiogenesis. Transarterial microembolization (TAME), a minimally invasive radiological procedure, may present an innovative therapeutic approach. This review aims to consolidate current knowledge and experiences regarding TAME as a therapeutic modality for alleviating chronic joint pain associated with OA. It explores the role of TAME, focusing on its indications, patient selection, clinical outcomes, and future perspectives. Potential complications and associated risks are systematically addressed, alongside proposed strategies for risk mitigation and effective management.The presented patient cases originate from our institution, supplemented by a thorough review of relevant literature retrieved from PubMed.TAME represents a promising therapeutic approach, providing relief from the burden of joint diseases and substantially enhancing patient quality of life. Clinical outcomes emphasize the efficacy and safety of TAME in mitigating pain and improving functional capabilities in patients with chronic joint pain associated with OA. With mounting evidence of its therapeutic benefits and applicability to numerous joint-related pathologies, TAME offers a valuable addition to the arsenal of treatments for these conditions. · TAME is an innovative therapy for treating chronic joint pain related to OA.. · TAME is a technically challenging minimally invasive intervention requiring a high level of expertise.. · Understanding the challenges and complications of TAME can reduce risk and enhance procedural outcomes.. · Wilms LM, Jannusch K, Weiss D et al. Transarterial microembolization for the management of refractory chronic joint pain in osteoarthritis. Fortschr Röntgenstr 2024; DOI 10.1055/a-2288-5743.

Challenges and complications and their management of the transarterial microembolization for chronic musculoskeletal pain

Transarterial microembolization (TAME) is an increasingly well-known novel and minimally invasive treatment option for painful chronic musculoskeletal diseases that is gaining popularity. Although the safety and effectiveness of TAME have been established, limited knowledge of intraarticular and musculocutaneous arterial anatomy may lead to challenges and complications. This article aims to present cases illustrating these challenges and complications, based on multicenter experiences and a comprehensive literature review. Furthermore, the article also provides preventive tips, solutions, and follow-up strategies to reduce the learning curve for interventional radiologists and facilitate familiarity with post-TAME follow-up images for diagnostic radiologists. CLINICAL RELEVANCE STATEMENT: This article illustrates the intra- and post-interventional complications of transarterial microembolization (TAME) through detailed pictorial reviews, including how to distinguish them from normal angiographic findings. It provides strategies for their prevention, management, and follow-up, which can further improve clinical outcomes. KEY POINTS: • Transarterial microembolization for chronic musculoskeletal pain may result in intrainterventional challenges (IIC) and postinterventional complications (PIC), and their importance may be underestimated. • The intrainterventional challenges include microarterial perforation, arterial dissection, and catheter tip fracture, whereas postinterventional complications include tissue ischemia-related complications, puncture site hemorrhage, and arterial injury. • Being familiar with the intrainterventional challenges and postinterventional complications may help minimize the procedure risk and improve outcomes.

Transarterial Embolization for Adhesive Capsulitis of the Shoulder: Midterm Outcomes on Function and Pain Relief

PURPOSE

To determine the safety and potential effectiveness of transarterial embolization for adhesive capsulitis of the shoulder.

MATERIALS AND METHODS

This prospective study analyzed consecutive adult patients with adhesive capsulitis referred for embolization between January 2018 and May 2023 after a poor response to treatment (symptoms and limitation of motion in ≥2 axes; ≤120° flexion, ≤50° external rotation and/or internal rotation with the shoulder abducted 90°) persisting for >3 months after having completed ≥6 weeks of analgesics and physical therapy. Different types of pain and mobility were measured before embolization and 1, 3, and 6 months after embolization. Overall upper limb function (Quick Disabilities of Arm, Shoulder, and Hand) and patient satisfaction were measured before and 6 months after embolization. Long-term follow-up comprised telephone interviews and clinical history reviews.

RESULTS

A total of 20 patients (12 [60%] women; median age, 50.7; interquartile ranges [IQR], 45‒55 years) were included; 6 (30%) had diabetes and 15 (75%) were off work. Median duration of symptoms before embolization was 39.4 weeks (IQR, 28‒49 weeks), and median duration of rehabilitation therapy was 12.8 weeks (IQR, 8‒16 weeks). Six months after embolization, significant improvements were observed in nocturnal pain (P = .003), pain on moving (P = .001), external rotation (P < .001), internal rotation (P < .001), active flexion (P < .001), passive flexion (P = .03), active abduction (P < .001), passive abduction (P < .001), and overall function (P < .001). Despite objective improvements, patient satisfaction was nearly unchanged. Only 1 patient experienced a mild adverse event.

CONCLUSION

Transarterial embolization is safe and potentially effective in treating adhesive capsulitis of the shoulder refractory to conventional treatment. Clinical improvements were maintained in the mid to long term.

In vitro study of the embolic characteristics of imipenem/cilastatin particles

BACKGROUND

Imipenem/cilastatin (IPM/CS) has long been administered intravenously as a carbapenem antibiotic. However, since this agent is poorly soluble in liquid, occasional reports have described its use as a short-acting, temporary embolic agent. The purpose of this study was to elucidate the characteristics of IPM/CS particles, which are thought to have pain-relieving effects against osteoarthritis-related pain, as an embolic agent.

METHODS

Three aspects of IPM/CS as an embolic agent were evaluated in vitro: particle size; particle shape; and change in particle size over time. For particle size, the long diameter was measured.

RESULTS

Mean particle size (n=244) was 29.2±12.0 µm (range, 1-60 µm). Shape (n=109) was round in 18.35%, elliptical in 11.93%, and polygonal in 69.72%, showing that most particles were polygonal. In observations of changes in particle size over time (n=9), particles had decreased to 75% of their original size at 82±10.7 min, 50% at 89.3±9.14 min, 25% at 91.3±8.74 min, complete dissolved at 91.8±9.02 min. A rapid shrinkage in diameter was seen in the final period.

CONCLUSIONS

IPM/CS particles are ultrafine and the majority display a polygonal shape. This substance shows ultra-short embolic activity. This study revealed the characteristics of a substance that demonstrates an embolic effect not found in existing embolic materials.

Common Design, Data Elements and Core Outcome Measures Reported on Clinical Trials of Genicular Artery Embolization for Knee Osteoarthritis: An Interactive Systematic Review

RATIONALE AND OBJECTIVES

Genicular artery embolization (GAE) is an emerging, potentially effective treatment option in patients with knee osteoarthritis (OA). This study aimed to describe the current state of common design data elements (CDDEs) and core outcome measures (COMs) in recent trials of GAE for knee OA.

MATERIALS AND METHODS

A comprehensive search of seven online databases were searched within the Nested Knowledge AutoLit living review platform, followed by categorization of primary and secondary outcomes. Studies were tagged with the relevant outcomes of interest in each article. Results were synthesized and examined for the CDDEs.

RESULTS

Pain is the most frequent reported outcome, present in 23 of the 24 studies (95.8%). However, there is considerable variability in the description of in the study designs, procedural techniques, embolic materials, time points, and MRI parameters. Greater consistency is observed in eligibility criteria, and adverse events reporting. Although findings thus far have been favorable, current data is still constrained by the heterogeneity of the study design, embolization area nomenclature, limited follow-up, and in many cases, the absence of control group.

CONCLUSION

To enhance the potential for future meta-analyses and robust, evidence-based evaluations of GAE as a treatment for knee OA, further research is required to address the identified shortcomings. By establishing more standardized protocols, the efficacy and safety of GAE can be more accurately assessed and understood.

Musculoskeletal Embolotherapy

Painful articular musculoskeletal (MSK) conditions are common, debilitating and sometimes difficult to treat. Transcatheter embolisation may offer an alternative way to manage the pain associated with these conditions, but the field is still in its infancy. To date, the most commonly studied indication is knee osteoarthritis, but the technique has been trailed in multiple other tissue beds, including for adhesive capsulitis and tendinopathies. Whilst early results appear promising, the existing studies are mostly open-labelled and non-randomised; there is a need for high-quality evidence to robustly assess the procedures efficacy. In this review, we set out to evaluate the current evidence underlying the pathophysiology and mechanism of action of embolisation; discuss the technical aspects of the procedure including embolic selection, and appraise the published clinical outcomes and adverse effects. Finally, we discuss the future directions and research priorities in this rapidly developing field.

Evaluating the Safety and Effectiveness of Quick-Soluble Gelatin Sponge Particles for Genicular Artery Embolization for Chronic Knee Pain Associated with Osteoarthritis

PURPOSE

To evaluate the effectiveness and safety of genicular artery embolization (GAE) using quick-soluble gelatin sponge particles (QS-GSPs) to alleviate chronic knee pain associated with osteoarthritis.

MATERIALS AND METHODS

This retrospective study included 71 patients (97 procedures, including 26 patients for both knees) who underwent GAE to treat osteoarthritic knee pain between August 2019 and January 2022. QS-GSPs were used for all the procedures. Technical success was defined as the embolization of at least 1 feeding artery. Clinical outcomes were evaluated using a 10-point visual analog scale (VAS). Clinical success was defined as a decrease in the VAS score of >50%.

RESULTS

The technical success rate was 100% (97 of 97). The mean VAS scores at baseline, immediately after TAE, and at 1 day, 1 week, 1 month, 3 months, and 6 months after TAE were 6.3, 4.3, 5.0, 3.0, 2.9, 2.9, and 2.8, respectively. The clinical success rate was 72% (70 of 97 patients) at 6 months. No major adverse events were reported, and temporary skin color change (50.5%, 49 of 97) and hematoma at the puncture site (10.3%, 10 of 97) were observed.

CONCLUSIONS

GAE using QS-GSPs had a high technical success rate and was considered safe. Clinical outcomes using QS-GSPs were comparable with those of existing materials.

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.

Transcatheter arterial embolisation for the relief of shoulder and elbow chronic joint pain refractory to conventional treatment: Systematic review

Angiogenesis and accompanying nerve fibres might cause unsettling joint pain. Studies have suggested that transcatheter arterial embolisation (TAE) of these abnormal neovessels could relieve pain and symptoms in patients with upper limb joint pain refractory to conventional treatment. This study aims to investigate the efficacy and safety of TAE in treating chronic pain of shoulder and elbow joints that have been resistant to other treatments. Using six databases, a systematic review was performed following Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. The primary outcome involved changes in the visual analogue scale (VAS) after TAE; while secondary outcomes involved comparing other parameters where relevant. Average VAS decreased from baseline, then at 1 day, 1 week, 1 month, 3 months, 4 months, 6 months, 1 year, 2 years and 44 months (7.5 at baseline vs. 4.7, 4.3, 3.4, 2.1, 2.5, 1.2, 0.7, 1.1 and 0.1, respectively). Average Quick-DASH scores decreased from baseline, then at 1, 3 and 6 months (61.3 at baseline vs. 30.6, 19.3 and 6.9, respectively). Minor adverse events were reported in 27/143 (18.9%) patients, where they resolved spontaneously or with oral analgesia. TAE is a possible treatment option for refractory shoulder and elbow joint pain; however, randomised controlled trials are still required.

Endovascular Treatment of Incidentally Found Multiple Aneurysms Originating from a Bronchial Artery: A Case Report

Bronchial artery aneurysm (BAA) is a rare disease, and multiple aneurysms of a single bronchial artery are rarer. Regardless of the size of the lesion, it is at risk of rupture and can cause massive hemoptysis or severe pain. We report a rare case of bronchial artery embolization (BAE) of multiple aneurysms of a single bronchial artery. During medical examination, a 64-year-old female was diagnosed with multiple BAAs and endobronchial lesions in the right lower lung on CT 10 years prior to presentation to our hospital. Further evaluation of the lesions was recommended; however, the patient was lost to follow-up. The patient complained of dyspnea and visited our hospital, and the size of the BAA had increased on CT. BAE was done successfully using N-butyl-2-cyanoacrylate and detachable coils. Follow up CT after BAE showed significant decrease in extent of inflammatory lesion in the right lung.

Transcatheter embolisation in chronic musculoskeletal disorders

Chronic musculoskeletal conditions affect millions of patients worldwide resulting in disability, reduced quality of life, and have a profound economic impact on the individual and society. Current treatment strategies fail patients who have not responded to conservative management but are not surgical candidates. Over the last decade, transcatheter embolisation has emerged as a potential treatment for these difficult to treat patients. By exploiting pathological neovascularisation within conditions such as knee osteoarthritis, adhesive capsulitis, and tendinopathy, embolisation has been used to improve patients' pain and function. This review explores the rationale for musculoskeletal transcatheter embolisation, illustrating the technique, and latest evidence for the most common procedures.

Angiographic Analysis of Anatomical Variants in Adhesive Capsulitis Embolization

PURPOSE

To analyze the complex shoulder vasculature and identify potential challenges during adhesive capsulitis embolization (ACE).

MATERIALS AND METHODS

Two interventional radiologists evaluated angiographic findings from 21 ACE procedures. The suprascapular artery (SSA), thoracoacromial artery (TAA), coracoid branch (CB), circumflex scapular artery (CSA), and anterior/posterior circumflex humeral artery (ACHA/PCHA) were assessed for their presence, course, diameter within 1 cm of origin, angle to the proximal parent vessel, and distance from the clavicle.

RESULTS

83 arteries were embolized: CB (20.5%), TAA (19.3%), PCHA (19.3%), ACHA (16.9%), CSA (14.5%), and SSA (9.6%). The CSA had the largest diameter (4.3 mm), while CB had the smallest diameter (1.0 mm). An acute angle to the parent vessel was noted with the SSA, TAA, ACHA, and PCHA. A common origin for CSA and PCHA was noted in 2 patients. A common origin for TAA and SSA was also noted in one patient. The CB appears perpendicular to the axillary artery and courses vertically toward the coracoid process. The TAA branches off the axillary artery and courses along the medial border of the pectoralis minor. The PCHA and ACHA originate from the axillary artery. The CSA is located on the medial side of axillary artery. The SSA originates from the thyrocervical trunk and courses laterally toward the superior border of the scapula.

CONCLUSION

An anatomical-technical guide is provided to help interventional radiologists during ACE to treat adhesive capsulitis.

Frozen Shoulder

Adhesive capsulitis (AC) develops spontaneously without a known cause and is a common cause of painful shoulder. The natural history of AC can last until 36 months and it is classically considered a self-limiting entity, however there is a high rate of refractory cases to conventional treatment with residual deficits during years. There is no consensus on the therapeutic guidelines to be followed in patients with AC. Several authors have pointed out the relevance of hypervascularization of the capsule in the pathophysiology of AC, that is why the objective of transarterial embolization (TAE) is to decrease the abnormal vascularization responsible for the inflammatory-fibrotic state that occurs in AC. TAE has now emerged as a therapeutic option in refractory patients. We describe the most important technical aspects of TAE and review the current literature on arterial embolization as a treatment for AC.

Embolic Decision Making in Musculoskeletal Embolization

In his pioneering work, Okuno and colleagues demonstrated the benefit of musculoskeletal (MSK) embolization, using imipenem as an embolic agent, in various diseases such as knee osteoarthritis (KOA), adhesive capsulitis (AC), tennis elbow and other sports injuries. As imipenem is a last-resort, broad spectrum antibiotic, its use is often not feasible depending on countries and their drug regulation. Since then, several other studies have used other material products such as microparticles or liquid embolics. In addition, several products in development or that are used in other indications may prove useful after full clinical evaluation of safety and efficacy. In this article we will develop our recommendations, through an analysis of recent publications on MSK embolization.

Knee and Shoulder Vascular Anatomy

In the past decade, angiographic studies have demonstrated neovessels in or in the vicinity of affected joints in many musculoskeletal conditions that used to be considered wear and tear joint disease, such as knee osteoarthritis, frozen shoulder, and overuse injuries. The novelty of this finding is showing the presence of neovascularity at an angiographically detectable level, as compared to histologically evident neovessels that had been discovered years ago. These neovessels have now become the target of interventions in a growing field called muscoskeletal embolotherapy. An in-depth and all-encompassing understanding of the vascular anatomy that could specifically assist performing of these procedures is paramount. Such an understanding will help ensure success in clinical outcomes and avoid much dreaded complications. This review discusses the vascular anatomy relevant to the 2 most commonly performed musculoskeletal embolotherapies, genicular artery embolization and transarterial embolization for frozen shoulder.

A Retrospective Comparison of the Efficacy of Embolization with Imipenem/Cilastatin and Microspheres in the Management of Chronic Shoulder Pain

PURPOSE

To compare the efficacy of embolization with imipenem/cilastatin and microspheres in chronic shoulder pain.

METHODS

This retrospective study included 29 patients who underwent embolization for chronic shoulder pain between June 2017 and March 2022 with calibrated MSs from 100 to 250 µm or IMP/CS. The main objective was the clinical success evaluated by the Minimum Clinically Important Difference (MCID) at 3 months after the procedure, validated if the patient responded yes to 2 questions: (1) Is the pain less severe than before the procedure? (2) Are you satisfied with the procedure? The decrease in visual analogue pain scale scores and the safety of the procedure were evaluated.

RESULTS

Embolization was achieved in all patients. In the MS group, 4/15 patients (26.7%) experienced clinical success at 3 months according to MCID versus 10/14 patients (71.4%) in the IMP/CS group (p = 0.02). The mean VAS decreases were respectively  - 28.6% ± 34.6 in the MS group and  - 36.8% ± 27.8 in the IMP/CS group at 1 month (p = 0.50), - 29.9% ± 29.0 and - 39.6% ± 23.0 at 3 months (p = 0.33) and - 30.6% ± 32.8 and - 46.6% ± 28.4 at 6 months after the procedure (p = 0.26). Eleven patients (73.3%) in the MS group and 3 patients (21.4%) in the IMP/CS group had complications (p = 0.01). Among them, 2/15 patients (13.3%) had transient skin ischaemia in the MS group.

CONCLUSION

Embolization with IMP/CS may be more effective and safer than MSs in the management of chronic shoulder pain.

Clinical Outcomes of Transarterial Embolization for Chronic Achilles Tendinopathy Refractory to Conservative Treatment: A Pilot Study

PURPOSE

To evaluate the effectiveness and safety of transarterial embolization (TAE) for chronic Achilles tendinopathy (AT) refractory to conservative treatment.

MATERIALS AND METHODS

This retrospective study included 20 patients (12 men and 8 women; mean age, 30.3 years) who received TAE using imipenem/cilastatin sodium for refractory chronic AT from May 2019 to April 2021. Nine patients had bilateral involvement. A total of 29 procedures were performed (8 for nonathletes and 21 for athletes). If feasible, embolization was performed superselectively of the arterial branch demonstrating hypervascularity, early venous drainage, and/or supplying the pain site noted using a radiopaque marker. The visual analog scale (VAS, 0-10) score was used to assess pain symptoms at baseline and during the follow-up period (1 day; 1 week; 1, 3, and 6 months; and open period). Clinical success was defined as a decrease of >50% in the VAS score at 6 months when compared with baseline.

RESULTS

In 25 (86.2%) of 29 procedures, clinical success was achieved. Significant decreases in the VAS scores were noted at 1 day, 1 week, 1 month, 3 months, and 6 months (6.86 at the baseline vs 3.48, 3.41, 3.10, 2.55, and 1.62, respectively; all P < .01). For patients available for the 12- and 24-month follow-ups (n = 19 and 6, respectively), the mean VAS scores significantly decreased (6.84 vs 2.00 and 7.33 vs 1.17, respectively; all P < .01). No serious adverse events were observed during follow-up.

CONCLUSIONS

TAE may alleviate pain for patients with chronic AT refractory to the conservative treatment with a low risk of adverse events.

Transcatheter Arterial Embolization for Alleviating Chronic Musculoskeletal Pain and Improving Physical Function: A Narrative Review

Chronic musculoskeletal pain imposes immense suffering and diminishes the quality of life for millions of patients worldwide; the pain persists despite the use of standard conservative treatments. Increases in our understanding of the pathophysiological mechanisms underlying musculoskeletal disorders indicate the involvement of inappropriate angiogenesis. Accordingly, the resulting neovessels are the target of emerging treatments for chronic musculoskeletal pain, including transarterial embolization. The use of this noninvasive procedure to treat pain refractory to standard therapy in a variety of musculoskeletal conditions is the focus of numerous recent investigations. Here, we describe the pathophysiological indications for the use of transarterial embolization and summarize the findings of studies investigating its use in a variety of histopathological conditions and anatomical sites.

Alteration of chronic inflammatory status by transarterial embolization in frozen shoulder evaluated by 18-fluorine-fluoro-2-deoxyglucose positron-emission tomography/computed tomography

BACKGROUND

Frozen shoulder (FS) is speculated to have an inflammatory etiology. On angiography, abnormal angiogenesis is observed around the affected shoulder, suggesting a possible source of inflammation and pain. The effectiveness and safety of transarterial embolization (TAE) targeting abnormally proliferating blood vessels have been reported. This study investigated changes in chronic inflammatory and hypoxic status before and after TAE in FS by 19-fluorine-fluoro-2-deoxyglucose (FDG) positron-emission tomography/computed tomography as a possible mechanism of the therapeutic response to TAE.

METHODS

Fifteen patients with unilateral FS, persistent for more than 6 months, who were refractory to conservative treatments, underwent TAE using the temporary embolic agent imipenem/cilastatin. Patients underwent positron-emission tomography/computed tomography with FDG (as a biomarker of inflammation) before and 8 weeks after TAE. Regional uptake was evaluated by the maximum standardized uptake value. The lesion-side-to-(contralateral-) normal-side uptake ratio was also calculated. Pain and functional scales, range-of-motion, and laboratory tests, including white blood cell, C-reactive protein, interleukin 6, vascular endothelial growth factor, and tumor necrosis factor α were evaluated.

RESULTS

On FDG-PET, the average maximum standardized uptake value of the lesion-side was significantly greater than that of the normal-side (maximum standardized uptake value before TAE: 3.11 ± 1.25 vs 1.95 ± 1.15, P = .0001; 8-weeks post-TAE: 2.36 ± 0.74 vs 1.78 ± 0.69, P = .0002). The mean lesion-side-to-(contralateral-) normal-side uptake ratios before TAE (1.71 ± 0.60) decreased after TAE (1.37 ± 0.29, P = .011). The decrease of FDG uptake (-21.1 ± 12.2%) showed a significant correlation with the change in the pain scale score (r = -0.56, P = .039) and extension score (r = -0.59, P = .026).

CONCLUSION

Chronic inflammation in FS, as demonstrated by FDG uptake, was decreased after TAE. Thus, chronic inflammation is likely to be an underlying mechanism that should be targeted for symptomatic improvement of frozen shoulder.

Feasibility of Neovessel Embolization in a Large Animal Model of Tendinopathy: Safety and Efficacy of Various Embolization Agents

Targeting neovessels in chronic tendinopathies has emerged as a new therapeutic approach and several embolization agents have been reported. The aim of this study was to investigate the feasibility of embolization with different agents in a porcine model of patellar tendinopathy and evaluate their safety and efficacy. Eight 3-month-old male piglets underwent percutaneous injection of collagenase type I to induce patellar tendinopathies (n = 16 tendons). They were divided into four groups (2 piglets, 4 tendons/group): the control group, 50–100 µm microspheres group, 100–300 µm microspheres group, and the Imipenem/Cilastatin (IMP/CS) group. Angiography and embolization were performed for each patellar tendon on day 7 (D7). The neovessels were evaluated visually with an angiography on day 14. The pathological analysis assessed the efficacy (Bonar score, number of neovessels/mm²) and safety (off-target persistent cutaneous ischemic modifications and presence of off-target embolization agents). The technical success was 92%, with a failed embolization for one tendon due to an arterial dissection. Neoangiogenesis was significantly less important in the embolized groups compared to the control group angiographies (p = 0.04) but not with respect to histology (Bonar score p = 0.15, neovessels p = 0.07). Off-target cutaneous embolization was more frequently depicted in the histology of the 50–100 µm microspheres group (p = 0.02). Embolization of this animal model with induced patellar tendinopathy was technically feasible with different agents and allowed assessing the safety and efficacy of neovessel destruction. Particles smaller than 100 µm seemed to be associated with more complications.

Safety and Efficacy of Embolization with Microspheres in Chronic Refractory Inflammatory Shoulder Pain: A Pilot Monocentric Study on 15 Patients

Purpose: Musculoskeletal (MSK) embolization is emerging in tendinopathy treatment. The objective of this study was to assess the efficacy and safety of MSK embolization with microspheres in the treatment of chronic shoulder pain. Patients and methods: This retrospective monocentric study included patients with chronic shoulder pain resistant to 6 months or more of conventional therapies who were treated with MSK embolization between 2017 and 2021. Embolization was performed using calibrated 100–250 µm microspheres. Clinical success was defined as pain reduction, i.e., a decrease in the visual analogue scale (VAS) pain score of ≥50% at 3 months after MSK embolization as compared to baseline. Adverse events were collected. Results: Fifteen patients (11 women, 4 men) were included, with a median age of 50.3 years (IQR: 46.7–54.5). The median duration of symptoms was 26.6 months (20.6–39.8). The median VAS pain scores were 7.0 (7.0–8.0) at baseline, 6.0 (3.5–7.0) at 1 month, 5.0 (4.5–6.5) and 5.0 (3.0–7.4) at 3 months and 6 months (p = 0.002). Three patients (20%) reported clinical success at 3 months. Three patients experienced minor complications after embolization (paresthesia, n = 2; transient osteo-medullary edema, n = 1) and two patients had moderate complications (transient skin ischemia). Conclusion: MSK embolization with microspheres for treatment of refractory chronic shoulder pain showed moderate results in terms of clinical success and safety.

Transarterial Embolization for the Treatment of Chronic Musculoskeletal Pain: A Systematic Review of Indications, Safety, and Efficacy

OBJECTIVE

The study objective was to evaluate the safety and efficacy of transcatheter arterial "embolization" (TAE) in the treatment of chronic "musculoskeletal pain" refractory to standard therapy.

METHODS

PubMed, EMBASE, and Cochrane Central Register of Controlled Trials were searched for original research articles evaluating TAE in patients with musculoskeletal conditions from database inception to January 21, 2020. Search terms employed were as follows: "embolization", "pain", "knee osteoarthritis", joint replacement, epicondylitis, tenderness, inflammation, WOMAC (Western Ontario and McMaster Universities Osteoarthritis Index), microspheres, Embozene, geniculate artery, neovascularity, transcatheter, embolic, imipenem/cilastatin sodium, angiogenesis, and "musculoskeletal". Studies involving particle "embolization" for painful musculoskeletal conditions were included. Studies of TAE for hemarthrosis or malignancy-related "musculoskeletal pain" were excluded.

RESULTS

The primary search yielded 1,099 sources; 7 articles and 4 abstracts were included for data extraction. All were cohorts or case series, with low risk of bias and moderate to poor level of evidence. Heterogeneity between studies was high, precluding meta-analysis. The reviewed studies reported the safety and efficacy of TAE for the treatment of "knee osteoarthritis"; adhesive capsulitis of the shoulder; tendinopathy/enthesopathy of the knee, shoulder, elbow, and ankle; and cervical myalgia. All TAEs were reported as technically successful without major complications or subsequent serious adverse events, including no reported osteonecrosis, cutaneous ulceration, limb ischemia, cartilage degeneration, or myotendinous injury. TAE significantly reduced pain and improved function for all of the treated conditions, with durable response up to 24 months post procedure.

CONCLUSION

TAE appears to be a safe and effective treatment for some types of chronic refractory "musculoskeletal pain". Randomized placebo-controlled studies are necessary to confirm these findings.

Transcatheter arterial embolization for benign chronic inflammatory joint pain: a systematic review and meta-analysis

PURPOSE

To evaluate the efficacy and safety of transcatheter arterial embolization for the treatment of chronic inflammatory joint pain via a systematic review and meta-analysis.

MATERIALS AND METHODS

The MEDLINE and EMBASE databases were searched for studies reporting outcomes in patients with chronic inflammatory joint pain treated with transcatheter arterial embolization. Meta-analyses of pain score changes, changes in proportions of patients on analgesic medications, range of motion changes, technical success rates, and adverse events rates were performed. Subgroup analyses were conducted with respect to pain site (knee vs. shoulder).

RESULTS

Fourteen observational studies, including 346 patients, were reviewed. The pooled technical success rate was 95.8%, and no major adverse events were observed. The pooled mean difference in pain score at 1 week; 1, 3, and 6 months; and 1 year were 3.1, 4.0, 4.2, 5.1, and 5.5, respectively. Subgroup analysis demonstrated that shoulder embolization was associated with greater reduction of pain than knee embolization at 3 and 6 months (p<0.001 and p=0.018, respectively), whereas there was no significant difference in this regard between the sites at 1 month (p=0.734). The pooled proportions of patients on analgesic medication at baseline, 1, 3, 6, and 12 months were 81.1%, 36.3%, 42.3%, 28.2%, and 22.4%, respectively. The pooled estimated increases in range of motion among patients who underwent shoulder embolization were 55.6° for anterior elevation and 64.7° for abduction.

CONCLUSION

Transcatheter arterial embolization is an effective and safe therapeutic option for patients with chronic inflammatory joint pain.

Evaluation of autonomic nervous system responses during isometric handgrip exercise using nonlinear analysis of heart rate variability

[Purpose] The purpose of this study was to examine, using a plethysmogram of the fingertips, autonomic responses at motor intensities of 30% or 50% of maximum voluntary contraction (MVC) during isometric handgrip exercise (IHG). [Participants and Methods] The participants of this study were 15 healthy persons. The finger volume pulse wave of each participant was measured continuously, using a BACS Advance equipment (TAOS Co.), for a total of 17 minutes: 5 minutes before IHG (Pre), 2 minutes during IHG (IHG), the first 5 minutes after IHG (Post 5), and then the second 5 minutes after IHG (Post 10). To evaluate autonomic nervous system activity, we used the Detrended fluctuation analysis (DFA) and Approximate Entropy (ApEn). [Results] During IHG, the pulse rate was significantly higher and the ApEn value was significantly lower than during the other periods of measurement. Compared to other analyzed parameters, ApEn decreased during IHG, but returned to its initial Pre period level during the Post 5 period. The α₁ value derived from the DFA analysis remained at a value of 1 during each measurement time point, indicating the absence of malfunctions in autonomic response. [Conclusion] Isometric handgrip exercise with 30% MVC seemed to be useful for the assessment of autonomic nervous system response.

Collagenase-Induced Patellar Tendinopathy with Neovascularization: First Results towards a Piglet Model of Musculoskeletal Embolization

Background: Therapeutic strategies targeting neovessels responsible for musculoskeletal chronic pain have emerged, including neovessels embolization. Our study aimed to develop a large animal model of patellar tendinopathy with neovascularization. Methods: Nine 3-month-old male piglets (18 patellar tendons) received percutaneous injections of increasing doses of collagenase (0 to 50 mg) at day 0 (D0). Tendinopathy was evaluated by ultrasound (D7 and D14). Neovascularization was evaluated visually and on angiographies. Bonar score was used for histological analysis (D14). Correlations were evaluated using Spearman’s rank (Rs) test. Results: Research protocol was well tolerated. All tendons were enlarged with a median increase of 31.58% [25–40.28] at D7 (p = 0.244) at D7 and 57.52% [48.41–91.45] at D14 (p = 0.065). Tendons with collagenase injection had more hypoechoic changes, with one tendon rupture (p = 0.012). Neovascularization was reported above 5 mg collagenase (p < 0.01) at D7 and D14 with dose-related neovessels induction (Rs = 0.8, p < 0.001). The Bonar score increased above 5 mg collagenase, correlated with the dose (Rs = 0.666, p = 0.003). Conclusions: The study shows the feasibility, safety and reproducibility of this new large animal model of patellar tendinopathy with neovascularization after collagenase injection. It will allow studying new treatments on direct embolization of neovessels by endovascular approach.

Cadaveric Classification of the Genicular Arteries with Implications for the Interventional Radiologist

PURPOSE

To document and assess the genicular arterial variation in a large multicenter cadaveric sample and generate an anatomical classification with implications for Genicular Artery Embolization (GAE).

MATERIALS AND METHODS

A sample of 212 donor body lower limbs were dissected from three medical school institutions. The descending genicular artery (DGA), superior lateral genicular artery, superior medial genicular artery, middle genicular artery, inferior lateral genicular artery, inferior medial genicular artery, and anterior tibial recurrent artery (ATRA) were identified for gross anatomical appearance, location of origin, diameter of vessels, and variation in branching patterns.

RESULTS

A total of 198 DGA, 204 popliteal origin genicular arteries and 183 ATRA were adequately preserved and reviewed. Three types (A:26%, B: 71%, C:5%) of DGA branching patterns were proposed along with six types (I: 28%; II: 22%; III 15%; IV: 15%: V 10%; VI: 6%) of popliteal origin genicular artery branching variants. Right vs left comparisons did not reveal clinically significant differences in vessel distance (p = 0.30 - 0.82).

CONCLUSION

Despite the large number of possible anatomical variations of the genicular arteries, six main patterns corresponded to over 96% of the cases. The description and classification of the genicular arterial anatomy may provide useful information to the interventional radiologist and add to the technical nuances of GAE.

A Review of Musculoskeletal Embolization to Treat Pain Outside of the Knee

Chronic inflammation leading to musculoskeletal pain has garnered interest in the past decade with the success of genicular artery embolization for knee pain secondary to osteoarthritis. Outside the knee joint, musculoskeletal embolization has been applied to other anatomical locations, mainly shoulder pain secondary to adhesive capsulitis and elbow pain secondary to lateral epicondylitis. The success of these early trials and other case reports highlights the efficacy of musculoskeletal embolization and its future potential.

Results from a US Investigational Device Study of Adhesive Capsulitis Embolization (ACE) in the treatment of Shoulder Pain: The ACE Study

PURPOSE

To evaluate the safety and efficacy of arterial embolization to relieve shoulder pain secondary to Adhesive Capsulitis (AC).

METHODS AND MATERIALS

20 patients (18F, 2M: Mean age 51y) with AC resistant to > 30 days of conservative treatment were enrolled in a multi-center prospective study. Adhesive Capsulitis Embolization (ACE) was performed with 75 or 200 um spherical particles. Subjects were assessed before and after the procedure with MRI, VAS (0-100 mm), Single Assessment Numeric Evaluation (SANE, 0-100), and American Shoulder and Elbow Surgeons (ASES, 0-100) scores. Adverse Events (AEs) were recorded at all follow-up time points.

RESULTS

Hypervascularity was identified and embolization was technically successful in all patients with 83 arteries embolized in 20 patients. Baseline VAS, SANE, and ASES scores before the procedure were 89.2 mm, 27.2, and 30.9 mm, respectively. 1 (n=19), 3 (n=18), and 6 (n=12) months follow-up demonstrated significant improvements: 1 mo VAS (Δ Mean = -31.8, p = 1.2E-11), SANE (Δ Mean = 22.1, p = 1.8E-8), and ASES (Δ Mean = 14.2, p = 4.3E-5): 6 mon VAS (Δ Mean = -62.1, p = 7.0E-11) SANE (Δ Mean = 55.4, p = 4.1E-10), and ASES (Δ Mean = 44.5, p = 1.8E-6). Due to the coronavirus pandemic, the study was ended early and six patients did not complete the 6-month follow-up. No major adverse events were noted.

CONCLUSION

Interim findings suggest that arterial embolization is safe and effective for patients with AC refractory to conservative treatment.

Current Status of Trans-Arterial Embolization in Pain Management of Musculoskeletal Inflammatory Conditions - An Evidence-Based Review

OBJECTIVE

To summarize the literature on trans-arterial embolization in inflammatory musculoskeletal conditions, focusing on efficacy and safety.

MATERIALS AND METHODS

PRISMA guidelines were followed. A systematic literature search revealed 19 studies, with a total of 394 participants, eligible for inclusion.

RESULTS

The included studies consisted of case reports/series and non-randomized interventional studies, with knee osteoarthritis and adhesive capsulitis of the shoulder as the most frequent conditions. In all studies except one, pain was reduced up to four years after treatment. All adverse events were transient. Due to high heterogeneity, meta-analysis was not possible.

CONCLUSION

The included early studies showed encouraging results regarding efficacy and safety. However, randomized, placebo-controlled trials are warranted.

Intra-Arterial Infusion of Imipenem/Cilastatin Sodium through a Needle Inserted into the Radial Artery as a New Treatment for Refractory Trapeziometacarpal Osteoarthritis

PURPOSE

To evaluate the efficacy and safety of intra-arterial infusion of temporary embolic material with/without radiographic monitoring via a needle placed into the radial artery to occlude abnormal neovessels for trapeziometacarpal osteoarthritis.

MATERIALS AND METHODS

Thirty-one patients having Eaton stage II or III osteoarthritis, with a symptom duration longer than 6 months, resistant to conservative therapy for at least 3 months were prospectively enrolled. All procedures were performed by infusing imipenem/cilastatin sodium through a 24-gauge needle that was percutaneously inserted into the radial artery. Seven patients underwent the procedure with fluoroscopy, and 21 patients underwent the procedure without fluoroscopy. The mean Quick Disabilities of the Arm, Shoulder and Hand (QuickDASH) score, numerical rating scale (NRS), and Patient Global Impression of Change (PGIC) scale were evaluated before and at 2, 6, and 24 months after the first procedure.

RESULTS

Technical success was 100%. The mean procedure time (from the beginning of local anesthesia to the removal of needle) was 2.9 minutes ± 1.6. The QuickDASH score improved from the baseline to 2, 6, and 24 months (49.2 ± 11.2 vs 22.1 ± 11.2, 20.9 ± 16.6, and 19.5 ± 16.1, respectively, all P <.001). The NRS improved from the baseline to 2, 6, and 24 months (7.2 ± 1.1 vs 3.1 ± 1.8, 2.8 ± 2, and 2.5 ± 2.1, respectively, all P <.001). Improvement on PGIC was observed in 84%, 81%, and 77% of patients at 2, 6, and 24 months, respectively. No major adverse events were encountered.

CONCLUSIONS

Intra-arterial infusion of temporary embolic material is a feasible treatment option for trapeziometacarpal osteoarthritis.

Short-term Results of Transcatheter Arterial Embolization for Chronic Medial Epicondylitis Refractory to Conservative Treatment: A Single-Center Retrospective Cohort Study

PURPOSE

To evaluate the effectiveness and safety of transcatheter arterial embolization (TAE) for chronic medial epicondylitis (ME) refractory to conservative treatments.

MATERIALS AND METHODS

This retrospective study included ten patients (14 procedures) who underwent TAE between May of 2018 and April of 2020 to treat chronic ME refractory to conservative treatments for at least 3 months. Imipenem/cilastatin sodium was used in 12 procedures, and quick-soluble gelatin sponge particles were used in the ensuing two procedures as an embolic agent. The visual analogue scale (VAS, 0-10) score and Quick Disabilities of the Arm, Shoulder, and Hand (Quick-DASH) scores were assessed at baseline and at different post-treatment times (1 day; 1 week; 1, 3, and 6 months; and an open period). The clinical success of the procedure was defined as a decrease of more than 70% in the Quick-DASH scores at 6 months compared to the baseline.

RESULTS

Clinical success was achieved in 12 of 14 procedures (85.7%). No major complications were observed during the follow-up periods. The mean VAS scores were significantly decreased at 1 day, 1 week, 1 month, 3 months and 6 months (7.6 at baseline vs. 3.6, 3.6, 3.6, 3, and 0.9 after treatment; all P < .01). The mean Quick-DASH scores at baseline decreased significantly at 1 day, 1 week, and at 1, 3, and 6 months after treatment (71.9 vs. 48.5, 44, 37.7, 30.2, and 8.4; all P < .01). These improvements endured in nine patients for up to 12 months after treatment.

CONCLUSION

TAE effectively and safely relieved pain and promoted functional recovery in chronic ME patients refractory to conservative treatments. TAE may be a feasible treatment option for patients with ME intractable to conservative treatments.

A Rat Model of Frozen Shoulder Demonstrating the Effect of Transcatheter Arterial Embolization on Angiography, Histopathology, and Physical Activity

PURPOSE

To assess the angiographic findings and the effects of transcatheter arterial embolization on physical activity and histopathology using a frozen shoulder rat model.

MATERIALS AND METHODS

First, the angiographic and histopathologic findings of rats in which the shoulder was immobilized with molding plaster for 6 weeks (n = 4) were compared to control rats with normal non-immobilized shoulders (n = 4). Next, a total of 16 frozen shoulder rats were divided into 2 groups. In the transcatheter arterial embolization group (n = 8), imipenem/cilastatin was injected into the left thoracoacromial artery. The changes of physical activity before and after procedures were evaluated and compared with a saline-injected control group (n = 8). Histopathologic findings were also compared between the 2 groups.

RESULTS

Angiography revealed abnormal shoulder staining in all of the rats with a frozen shoulder. On histopathology, the numbers of microvessels and mononuclear inflammatory cells in the synovial membrane of the joint capsule were significantly higher compared with the control rats (both P = .03). In the transcatheter arterial embolization group, the running distance and speed were improved (P = .03 and P = .01, respectively), whereas there were no significant differences in the control group. The number of microvessels and mononuclear inflammatory cells in the transcatheter arterial embolization group were significantly lower than the control group (P = .002 and P = .001, respectively).

CONCLUSIONS

The rat frozen shoulder model revealed the development of neovascularization. Transcatheter arterial embolization decreased the number of blood vessels and inflammatory changes in the frozen shoulder and increased the moving distance and speed of the rats.

Clinical Outcomes of Transcatheter Arterial Embolization for Secondary Stiff Shoulder

PURPOSE

To assess the clinical outcomes of transcatheter arterial embolization (TAE) for secondary stiff shoulder (SSS).

MATERIALS AND METHODS

This is a retrospective analysis of prospectively collected data performed between January 2017 and December 2019. This study comprised 25 patients (20 women and 5 men; median age, 49 years; range 27-59) with SSS resistant to conservative management during at least 3 months. The median time of stiffness was 12 months. The etiology of SSS was postoperative in 14 patients (56%) and posttraumatic in the remaining 11 patients (44%). Periods of immobilization in all patients were associated. TAE was performed, and technical aspects, adverse events, changes for pain, and physical examination before and 6 months after TAE were assessed.

RESULTS

Abnormal vessels were observed in 20 of 25 (80%) of the procedures. Transitory cutaneous erythema was noted in 4 patients treated after TAE. Significant differences were observed in the median pain visual analog scale reduction between before and 6 months after TAE (8 vs 2, P < .001). Shoulder mobility significantly improved in both flexion and abduction degrees between before and at 6 months after TAE in (70° vs 150°; P < .001). No symptoms of recurrence appeared.

CONCLUSIONS

TAE can result in pain reduction and mobility improvement in patients with SSS refractory to conservative therapy.

Genicular Artery Embolization to Improve Pain and Function in Early-Stage Knee Osteoarthritis-24-Month Pilot Study Results

Ten patients with painful early-stage knee osteoarthritis underwent transcatheter arterial embolization of neoangiogenic branches from genicular arteries. At 12 months, 6 patients had responded to treatment according to study criteria. Median pain, function, and quality-of-life scores had improved by 15.4%, 21.3%, and 100%, respectively, for the 10 patients. Median 30-second chair stand test and 6-minute walk test scores had improved by 43% and 26%, respectively. No major adverse events occurred. Improvements following transcatheter arterial embolization provide evidence that embolization might be an effective treatment technique for people with early-stage knee osteoarthritis, although more rigorous evaluation is required.

Mid-Term Results of Transcatheter Arterial Embolization for Adhesive Capsulitis Resistant to Conservative Treatment

PURPOSE

To evaluate the mid-term clinical outcomes of transcatheter arterial embolization (TAE) for adhesive capsulitis (AC) resistant to medical treatments.

MATERIALS AND METHODS

This is a prospective analysis performed between February 2016 and February 2020. Inclusion criteria for TAE were shoulder pain, restriction of movement and no response to conservative treatment for at least 3 months. Demographic variables, risk factors, technical aspects, adverse events, changes by visual analogue scale (VAS) for pain and physical examination before and after TAE were assessed.

RESULTS

This study included 40 patients with AC (35 women and 5 men; mean age 50 ± 9 years old). Abnormal vessels were observed in 31/40 (77.5%) procedures. As embolic agent, imipenem/cilastatin was used. The mean follow-up was 21.2 ± 10.5 months. Significant differences were obtained in terms of pain reduction before and 6 months after TAE with the median visual analogue scale (VAS) of 8 vs. 0.5, P = 0.0001. Substantial differences were found regarding mobility in flexion and abduction before and 6 months after embolization, respectively (79.5° ± 18.5° vs. 133° ± 24.5°, P = 0.0001; 72.4° ± 18.8° vs. 129.7° ± 27.9°, P = 0.0001). No complications occurred. Complete recovery was obtained in 37/40 (92.5%) patients and partial recovery in 2/40 (5%). No clinical recurrence appeared.

CONCLUSIONS

Clinical results of transcatheter arterial embolization with imipenem/cilastatin are effective and stable in the mid-term follow-up for patients presenting with AC resistant to conservative treatments.

Biomarkers associated with idiopathic frozen shoulder: a systematic review

Background: The pathophysiology of idiopathic frozen shoulder (FS) remains poorly described. There is a lack of differentiation between idiopathic and secondary cause. The aim of this systematic review was to summarize the evidence regarding the pathophysiology of idiopathic FS on a molecular level and emphasize the clinical relevance. Methods: A database search of Medline, EMBASE and Cochrane Central Register of Controlled Trials from inception to April 2018 was performed. Participants who underwent previous injections or surgeries were excluded. A thorough selection and quality assessment process using the Cochrane Risk of Bias assessment tool and the Joanna Briggs Institute Critical Appraisal Checklist was conducted by two reviewers independently. Results: A total of 15 studies analyzing 333 study subjects were included. Twelve studies evaluated capsular tissue and three studies investigated blood samples. The tissue samples revealed increased expression of various inflammatory cytokines including interleukins, cyclooxygenase and tumor necrosis factor. Several types of acid-sensing ion channels (ASIC1 and ASIC3) were associated with disturbed neurogenesis and melatonin-regulated pain mechanism. The blood samples showed prevalence of specific interleukin and metalloproteinase genotypes. A decreased matrix metalloproteinase/tissue inhibitor of metalloproteinase ratio was found both in tissue and blood. Conclusion: The findings indicate an abnormal local neurogenesis with possible regulation through melatonin. The disturbance in remodeling of the extracellular matrix and in collagen translation, together with a persistent inflammation and an impaired healing, all interact in the process that leads to persistent fibrosis. There is global fibroplasia with localized anterior capsule contracture.

Effects of Transcatheter Arterial Microembolization on Persistent Trapezius Myalgia Refractory to Conservative Treatment

PURPOSE

To evaluate the safety and efficacy of transcatheter arterial microembolization for patients with trapezius myalgia.

MATERIALS AND METHODS

We retrospectively evaluated the prospectively collected data of patients with trapezius myalgia for > 6 months who were refractory to conservative treatment and were treated by transcatheter arterial microembolization between October 2017 and January 2019. Transcatheter arterial microembolization was performed using imipenem/cilastatin on the vessels of the transverse cervical artery, suprascapular artery, and circumflex scapular artery according to the region of pain.

RESULTS

Forty-two patients were treated by transcatheter arterial microembolization and followed up for 6 months. No major adverse events occurred related to the procedures. The brief pain inventory worst pain scores significantly improved at 1, 2, 3, and 6 months after transcatheter arterial microembolization (8.6 ± 1.3 (before procedure) vs. 5.1 ± 2.9, 4.4 ± 2.9, 4.1 ± 2.8, and 3.9 ± 2.9, respectively, P < 0.001). The brief pain inventory pain interference scores, including general activity, mood, walking ability, normal work, relations with others, sleep, and enjoyment of life, also significantly decreased at 1, 2, 3, and 6 months after transcatheter arterial microembolization compared to those at baseline (all P < 0.01). The clinical success rate at 6 months after transcatheter arterial microembolization was 71.4% (95% confidence interval, 55.4-84.3%).

CONCLUSION

Transcatheter arterial microembolization is a safe and effective treatment for persistent trapezius myalgia. Further evaluation with a control group is needed to confirm the effects of transcatheter arterial microembolization.

LEVEL OF EVIDENCE

Level 4, Case Series.

Non-neoplastic Disease Outside the Spine-Genicular Artery Embolization and Adhesive Capsulitis Embolization

Initial research into the treatment of pain secondary to knee osteoarthritis and shoulder adhesive capsulitis with embolization have yielded promising results. With further investigation, embolization may become a mainstay of treatment for pain from these two conditions.

[Transarterial Periarticular Embolization (TAPE): Indications and Initial Experience in Germany]

PURPOSE

 The purpose of this article is to demonstrate the potential indications, procedural technique and initial results of the transarterial periarticular embolization (TAPE).

MATERIAL AND METHODS

 TAPE was performed in three patients with chronic pain in different joints. In the first case the patient suffered from osteoarthritis of the shoulder, in the second case from epicondylitis humeri ulnaris ("golfer-elbow") and in the third case from patellar tendinitis ("jumpers-knee"). Clinical as well as pain assessment was performed pre and post-interventionally.

RESULTS

 TAPE was performed with technical success in all three patients. For vessel access, either a transradial or transfemoral access was chosen. The joint supplying vessels were catheterized superselectively with microcatheters and embolized with Imipenem/Cilastatin diluted in contrast medium. After embolization of the knee the patient demonstrated skin redness, which disappeared within one week. No further complications were noted. All patients reported significant pain relief within the first day after intervention.

CONCLUSION

 TAPE is a novel therapy for the treatment of persistent, chronic joint pain and tendinopathies, supported by publications from institutes outside of Europe. The initial experiences made in our institute are encouraging and suggest that TAPE may have the potential as an adjunct therapy option for patients with therapy-resistant chronic joint and tendinopathy-pain.

KEY POINTS

  · TAPE is a novel therapy for treatment of degenerative joint pain and tendinopathies. · TAPE is a technically challenging endovascular procedure and requires high interventional expertise. · TAPE may have the potential to develop to a minimally-invasive therapy option for patients with chronic joint pain.

CITATION FORMAT

· Katoh M, Schott P, Freyhardt P et al. Transarterial Periarticular Embolization (TAPE): Indications and Initial Experience in Germany. Fortschr Röntgenstr 2020; 192: 1046 - 1052.

Clostridium histolyticum (AA4500) for the Treatment of Adhesive Capsulitis of the Shoulder: A Randomised Double-Blind, Placebo-Controlled Study for the Safety and Efficacy of Collagenase - Single Site Report

Background/Hypothesis

Adhesive capsulitis of the shoulder results in pain and restricted movement of the glenohumeral joint. Hypothesis: There would be a difference in active range of movement in the affected shoulder of patients with adhesive capsulitis after receiving a series of injections of collagenase Clostridium histolyticum (CCH) compared to placebo.

Methods

This study reports the results from a single site that was part of a 321-participant, multicenter, double-blind, prospective parallel-group, randomized controlled clinical trial. Inclusion criteria: over 18 years of age, unilateral idiopathic adhesive capsulitis for >3 months, but <12 months. Exclusion criteria: recent physical therapy, injections, subacromial impingement, calcific tendonitis or glenohumeral joint arthritis in the affected shoulder. Subjects were randomized 3:1 to receive CCH 0.58 mg or placebo under ultrasound guidance. Injections were on days 1, 22, and 43. The primary outcome measure was a functional assessment of active range of movement.

Results

Overall, 37 patients were screened, 26 subjects were excluded, and 11 subjects were randomly assigned to the treatment group (n=9) or the control group (n=2). Both control and treatment groups showed improvement in ROM between baseline and day 95. In the treatment group, AROM improved from the baseline of 272.89° (SD 86.25) to 462.11° (SD 96.89) and the control group from 246.00° (SD 5.66) to 451.50° (SD 50.20) at day 95 with no statistical difference between groups p=0.78. Site data were in line with the whole study findings. Treatment-related adverse events at the injection site, including haematoma (bruising) and localised pain and swelling, were common.

Conclusion

Although the participants showed improvement in function, statistical significance was neither reached in the site nor the overall study cohort. Given the adverse events and the potential risks of the procedure, we would not recommend this drug for the treatment of adhesive capsulitis of the shoulder.

Level of Evidence

2, cohort from one site of RCT.