ABSTRACT
PURPOSE OF REVIEW: The purpose of this systematic review is to discuss emerging evidence in the field of viscosupplementation for chronic knee pain secondary to Osteoarthritis (OA). This review focuses on types of viscosupplementation that are clinically available currently, evidence to support their use, contraindications, and adverse events. RECENT FINDINGS: OA, also known as degenerative joint disease, is the most common form of arthritis in the United States, affecting 54.4 million, or 22.7% of the adult population. The knee is the most common joint affected in OA, with up to 41% involvement, 30% in the hands, and 19% in the hips. The pathophysiology of OA is complex, with contributing factors including mechanical stress to the joint, as well as many person-specific factors such as genetic susceptibility, ethnicity, nutrition, and sex. Treatment modalities include weight control, exercise, non-steroidal and steroidal anti-inflammatory drugs, opioids, intra-articular platelet-rich plasma, placebo, corticosteroid injection, intra-articular viscosupplementation, and surgery. Viscosupplementation consists of injection of hyaluronic acid (HA) into affected joints, intending to restore the physiologic viscoelasticity in the synovial fluid (SF) in the absence of inflammation. HA has also been shown to downregulate pro-inflammatory factors, such as PGE2 and NFkB, and proteases and proteinases known to break down the joint matrix.The contraindications for HA injection are similar to any other injection therapy, and adverse events are usually mild, local, and transient. Viscosupplementation (VS) is effective over placebo and more effective than NSAIDs and corticosteroids in pain reduction and improved functionality; however, guidelines recommend neither for nor against its use, demonstrating variability in the existing evidence base.Current VS options divide primarily into native vs. cross-linked and low-molecular-weight vs. high-molecular-weight. Current treatment options include Hylan g-f-20, Sodium Hyaluronate preparations (Suparts Fx, Euflexxa, Gelsyn-3, Durolane, Hyalgen), single-use agents (Gel-One, Synvisc-One, Monovisc), and Hyaluronan (Orthovisc, Monovisc, Hymovic). They share a common safety profile, and all have evidence supporting their efficacy. Their specific details are reviewed here. SUMMARY: OA is the most common form of arthritis. It is a chronic, debilitating illness with a high impact on the functionality and quality of life of a significant part of the population in the western world. Treatments include medical management, physical therapy, activity modification, injection, and surgery. VS effectively reduces pain, increases functionality, and delays surgery in the knee to treat osteoarthritis. While previous studies have demonstrated variable results, more evidence is becoming available generally supportive of the benefit of VS in the treatment of knee OA.
ABSTRACT
PURPOSE OF REVIEW: This is a comprehensive review of the superior hypogastric block for the management of chronic pelvic pain. It reviews the background, including etiology, epidemiology, and current treatment available for chronic pelvic pain. It then presents the superior hypogastric block and reviews the seminal and most recent evidence about its use in chronic pelvic pain. RECENT FINDINGS: Several definitions exist for chronic pelvic pain (CPP), making the diagnosis more challenging for the clinician; however, they commonly describe continuous pain lasting 6 months in the pelvis, with an overwhelming majority of patients being reproductive-aged women. This pain is often one of mechanical, inflammatory, or neuropathic. It is generally underdiagnosed and affects anywhere between 5 and 26% of women. The diagnosis of chronic pelvic pain is clinical, consisting of mainly of a thorough history and physical and ruling out other causes. The pathophysiology is often endometriosis (70%) and also includes PID, adhesions, adenomyosis, uterine fibroids, chronic processes of the GI and urinary tracts, as well as pelvic-intrinsic musculoskeletal causes. Treatment includes physical therapy, cognitive behavioral therapy, and oral and parenteral opioids. Interventional techniques provide an added tier of treatment and may help to reduce the requirement for chronic opioid use. Superior hypogastric plexus block is one of the available interventional techniques; first described in 1990, it has been shown to provide long-lasting relief in 50-70% of patients who underwent the procedure. Two approaches described so far, both under fluoroscopy, have seen similar results. More recently, ultrasound and CT-guided procedures have also been described with similar success. The injectate includes local anesthetic, steroids, and neurolytic agents such as phenol or ethanol. CPP is a common debilitating condition. It is diagnosed clinically and is underdiagnosed globally. Current treatments can be helpful at times but may fall short of satisfactory pain relief. Interventional techniques provide an added layer of treatment as well as reduce the requirement for opioids. Superior hypogastric plexus block provides long-lasting relief in many patients, regardless of approach. Evidence level is limited, and further RCTs could help provide better tools for evaluation and patient selection.
