Fluorine-18-fluorodeoxyglucose positron emission tomography-magnetic resonance imaging in the diagnosis of common peroneal nerve entrapment in a postspine surgery patient with sciatica

There are a variety of spinal and nonspinal causes of sciatica. Concomitant peripheral nerve entrapment is easily overlooked in patients with lower back pain and sciatica, especially in those who have undergone lumbar spine surgery. We reported a case of a 60-year-old woman with chronic postoperative lower back pain. Treatments focused on L5 radiculopathy were tried, but only partially relieved the pain. With the help of fluorine-18-fluorodeoxyglucose positron emission tomography-magnetic resonance imaging, entrapment neuropathy of the common peroneal nerve was detected. The diagnosis was further confirmed by ultrasonography (US), with complete pain relief after US-guided hydrodissection.