Chronic Knee and Ankle Pain Treatment through Selective Microsurgical Approaches: A Minimally Invasive Option in the Treatment Algorithm for Refractory Lower Limb Pain.

Abstract

Injury or compression of a sensory nerve is an under-reported source of disabling pain in the lower limb. It is known that peripheral nerve microsurgeons can reconstruct and rewire injured nerves to relieve chronic pain but this option remains not completely understood and ignored by most orthopaedic surgeons, neurologists, and pain therapists. In this paper, we describe our experience with knee and ankle peripheral nerve surgery to improve the condition of patients suffering from chronic, posttraumatic lower limb pain. Between 2015 and 2018, a retrospective investigation was performed including patients who underwent ankle and knee nerve surgery for posttraumatic chronic pain with at least 1 year of follow-up. Previous surgeries or type of trauma, pain location and characteristics, type of operation (reconstruction, decompression, or denervation), and number of nerves operated were listed. Selective neuropathy was confirmed by ultrasound-guided nerve blocks. Outcome was assessed combining the visual analogue scale (VAS) score at rest and during movement, functional indexes, drug use, and ability to work. A total of 34 patients (14 knee and 20 ankle) were included in this study. A statistically significant difference (p < 0.05%) in postoperative pain at rest and during activity was seen in both groups of patients. Good to excellent outcomes were recorded in 92 and 80% of patients treated, respectively, at the knee and the ankle levels. No major complications occurred, while a secondary procedure due to neuroma recurrence was necessary in seven patients (three knees and four ankles). Peripheral nerve microsurgery is a useful and minimally invasive tool to be added in the algorithm of treatment of chronic knee and ankle pain. Physicians should be trained to suspect a neuropathic origin of pain in absence of musculoskeletal signs of pathology, especially following trauma or surgeries.