Peripheral neuropathic pain (NP) is defined as pain caused by a lesion or disease affecting the peripheral somatosensory nervous system. Peripheral NP has a prevalence of 2.5% to 4% in the general population. Neuropathic pain is often severely debilitating, it is largely resistant to pharmacological treatment and its management and sequelae are a significant burden on healthcare resources. Peripheral NP has multiple etiologies but trauma leading to entrapment or compression of the nerves is an important cause. Nerve fibres in lower limbs are often involved in trauma to the ankle and the foot (eg, crush injury, fractures, ligament tears or sprains, and surgery) and this can result in chronic pain of moderate-to-severe intensity that often has predominantly neuropathic characteristics and is associated with functional limitations.
Injured or damaged sensory neurons in the injured limbs of patients with peripheral NP display enhanced or aberrant activity. When applied directly to injured nerve fibers, a combination of local anesthetics (LA) and steroids (LA-S) can suppress the secretion of inflammatory mediators35 and decrease ectopic discharge from the injured nerve, thereby alleviating edema and providing analgesia. Perineural injection of LA-S was reported for the treatment of posttraumatic or compression-related neuropathies in a case series. A systematic review and meta-analysis of 5 randomized controlled trials (RCT) in patients with peripheral NP after compression or trauma by our group revealed a small effect size in favor of perineural LA-S as compared to injection of only LA or conventional medical management (CMM).4 The studies in this review had clinical heterogeneity in terms of etiologies of peripheral NP and analgesic interventions, and considerable variation in analgesic benefit was also observed across the studies. An adequately powered RCT for patients with trauma- or compression-related peripheral NP would provide high-quality evidence on efficacy and adverse effects of perineural LA-S added to conventional management compared with conventional management alone.