The Benefits of Posterior Joint Infiltration in Chronic Low Back Pain

Overview

Lumbar facet joints have been implicated in chronic low back pain in over 45% of patients with isolated chronic common low back pain. Low back pain is the most common form of spinal pain, more chronic and severe than cancer pain. The annual prevalence of chronic low back pain ranges from 15% to 45% (one-off prevalence, 30%; lifetime prevalence, 54-80%). Because of this extremely high incidence, doctors from a wide range of specialities perform interventional techniques in a variety of settings. Facet joints have long been recognised as a source of back pain. In 1911, Goldthwait first recognised their role as a potential source of back pain. In 1933, Ghormley introduced the term "facet syndrome", defining lumbosacral pain with or without radicular pain. Badgley later suggested that facet joints could be a primary source of pain independently of spinal nerve compression. They demonstrated the role of posterior facet joints (PFJs) in a large number of patients with low back pain whose symptoms were not caused by a herniated disc. The underlying physiological concept of the PJF was introduced by Hirsch et al in 1963. They demonstrated that injecting a hypertonic saline solution into the region of the facet joints caused pain. The management of chronic low back pain due to zygapophyseal involvement (lumbar facet joints) consists primarily of conservative treatment. This is based on analgesics, anti-inflammatory drugs, physiotherapy and weight loss, where appropriate. Other non-surgical options may be proposed, including glucocorticoid injections into the facet joints. Glucocorticoid injections, which act by reducing inflammation, are commonly used in routine care to treat spinal pain. This pain may be due to a variety of pathologies, including discogenic or facet-related, or mixed, ligamentous or muscular, linked to a regional or global disorder of spinal statics. They are commonly used as a standard treatment for chronic spinal pain. Traditionally, in routine clinical practice, if there is significant paravertebral contracture and the clinical signs point to posterior joint involvement, a glucocorticoid injection is given in the doctor's surgery at the time of consultation, using anatomical landmarks to guide needle placement. However, few studies have demonstrated the efficacy of anatomical marking for infiltration of posterior joints, notably Cohen et al. Sui's systematic review of the use of this technique. With the advent of new imaging modalities such as ultrasound, more and more practitioners are turning to image-guided injections. To date, only the fluoroscopy-guided technique is considered reliable for facet joint infiltration. In order to improve the clinical efficacy of the various interventional therapeutic solutions, some authors have supported the use of ultrasound guidance. Several studies have been published comparing ultrasound-guided infiltration and infiltration using anatomical location in the shoulder region, the iliopsoas and in epicondilitis. While ultrasound guidance in areas such as the iliopsoas or the shoulder seems useful, it has not yet been proven that guidance is advantageous in spinal areas, such as the facet joints. To our knowledge, no randomised, methodologically sound study has yet been carried out to compare the benefit of ultrasound-guided infiltration versus infiltration with anatomical location. The aim of our study is to show that ultrasound-guided zygoapophyseal infiltration is superior to anatomically-guided infiltration in terms of pain assessment.