Review of Extraosseous Applications of Thermal Ablation in the Treatment of Moderate to Severe Large Joint Osteoarthritis

Thermal Protection Techniques for Image-guided Musculoskeletal Ablation

Percutaneous image-guided thermal ablation has gained wide acceptance among physicians for the treatment of benign and malignant tumors of the musculoskeletal system. Increasing evidence to support the efficacy of thermal ablation techniques in primary and adjuvant treatment of soft-tissue sarcomas, treatment of oligometastatic disease to bone and soft tissue, and metastatic pain palliation has positioned interventional oncology alongside surgery, systemic therapies, and radiation therapy as the fourth pillar of modern comprehensive cancer care. Despite the expanding indications and increasing use in clinical practice, thermal ablation carries a significant risk of injury to the adjacent vulnerable structures, predominantly the skin, bowel, and neural structures. Knowledge of the mechanism of action of each thermal ablation modality informs the physician of the attendant risks associated with a particular modality. Thermal ablation mechanisms can be divided into hypothermic (cryoablation) and hyperthermic (radiofrequency ablation, microwave ablation, high-intensity focused US, or laser). Active thermal protection techniques include hydrodissection, pneumodissection, direct skin thermal protection, and physical displacement techniques. Passive thermal protection techniques include temperature monitoring, biofeedback, and neurophysiologic monitoring. The authors provide an overview of the mechanism of action of the most commonly used thermal ablation modalities, review the thermal injury risks associated with these modalities, and introduce the active and passive thermal protective techniques critical to safe and effective musculoskeletal ablative therapy. ©RSNA, 2025 See the invited commentary by Tomasian and Jennings in this issue.

Cooled radiofrequency ablation of genicular nerves for knee osteoarthritis

Knee osteoarthritis (OA) is a prevalent and debilitating musculoskeletal condition that significantly affects the quality of life of millions of individuals worldwide. In recent years, cooled radiofrequency ablation (CRFA) has become a viable treatment option for knee OA. This review thoroughly evaluated the existing literature on CRFA therapy for knee OA. It delved into the mechanisms behind CRFA, evaluated its clinical efficacy, and investigated potential avenues for future research and application. The insights gained from this review are crucial for healthcare professionals, researchers, and policymakers, offering an updated perspective on CRFA's role as a viable therapeutic option for knee OA.

Upper limb and lower limb radiofrequency treatments in orthopaedics

Radiofrequency (RF) is a minimally invasive technique for disrupting or altering nociceptive pathways to treat musculoskeletal neuropathic and nociplastic pain. RF has been employed to treat painful shoulder, lateral epicondylitis, knee and hip osteoarthritis, chronic knee pain, Perthes disease, greater trochanteric pain syndrome, plantar fasciitis, and painful stump neuromas; it has also been employed before and after painful total knee arthroplasty and after anterior cruciate ligament reconstruction. The benefits of RF include the following:it is safer than surgery; there is no need for general anaesthesia, thereby reducing adverse effects; it alleviates pain for a minimum of 3-4 months; it can be repeatable if necessary; and it improves joint function and minimizes the need for oral pain medication. RF is contraindicated for pregnant women; unstable joints (hip, knee, and shoulder); uncontrolled diabetes mellitus; presence of an implanted defibrillator; and chronic joint infection (hip, knee, and shoulder). Although adverse events from RF are unusual, potential complications can include infection, bleeding, numbness or dysesthesia, increased pain at the procedural site, deafferentation effect, and Charcot joint neuropathy. Although there is a risk of damaging non-targeted neural tissue and other structures, this can be mitigated by performing the technique under imaging guidance (fluoroscopy, ultrasonography, and computed tomography). RF appears to be a valuable technique for alleviating chronic pain syndromes; however, firm proof of the technique's efficacy is still required. RF is a promising technique for managing chronic musculoskeletal of the limbs pain, particularly when other techniques are futile or not possible.

Pilot study for treatment of symptomatic shoulder arthritis utilizing cooled radiofrequency ablation: a novel technique

OBJECTIVE

To introduce cooled radiofrequency nerve ablation (C-RFA) as an alternative to managing symptomatically moderate to severe glenohumeral osteoarthritis (OA) in patients who have failed other conservative treatments and who are not surgical candidates or refuse surgery.

MATERIAL AND METHODS

This prospective pilot study includes a total of 12 patients experiencing chronic shoulder pain from moderate to severe glenohumeral OA. Patients underwent anesthetic blocks of the axillary, lateral pectoral, and suprascapular nerves to determine candidacy for C-RFA treatment. Adequate response after anesthetic block was over 50% immediate pain relief. Once patients were deemed candidates, they underwent C-RFA of the three nerves 2-3 weeks later. Treatment response was evaluated using the clinically validated American Shoulder and Elbow Surgeons (ASES) score and visual analog scale (VAS) to assess pain, stiffness, and functional activities of daily living. Follow-up outcome scores were collected up to 6 months after C-RFA procedure.

RESULTS

Twelve patients underwent C-RFA procedure for shoulder OA. VAS scores significantly improved from 8.8 ± 0.6 to 2.2 ± 0.4 6 months after the C-RFA treatment (p < 0.001). Patient's ASES score results significantly improved in total ASES from 17.2 ± 6.6 to 65.7 ± 5.9 (p < 0.0005). No major complications arose. No patients received re-treatment or underwent shoulder arthroplasty.

CONCLUSION

Image-guided axillary, lateral pectoral, and suprascapular nerve C-RFA has minimal complications and is a promising alternative to treat chronic shoulder pain and stiffness from glenohumeral arthritis.

US for Traumatic Nerve Injury, Entrapment Neuropathy, and Imaging-guided Perineural Injection

US is commonly performed to help diagnose traumatic peripheral nerve injury and entrapment neuropathy, particularly with superficial nerves, where higher spatial resolution provides an advantage over MRI. Other advantages of US include dynamic evaluation, easy contralateral comparison, fewer implant contraindications, less artifact from ferromagnetic debris, and facile needle guidance for perineural injections. The authors review peripheral nerve US for traumatic peripheral nerve injury with an emphasis on injury grading and entrapment neuropathy and describe best-practice techniques for US-guided perineural injections while highlighting specific techniques and indications. Online supplemental material is available for this article. ^©RSNA, 2022.