Piriformis Syndrome and Variants – A Comprehensive Review on Diagnosis and Treatment

Abstract

Piriformis syndrome (PS) is an entrapment neuropathy caused by the compression of the sciatic nerve by the piriformis muscle (PM). PS pain is described as deep, aching type with tingling and numbness, radiating from the gluteal and perineal area down to the lower limb. Rarely, this nondisc sciatica can present with associated pudendal neuralgia due to added pudendal nerve (PN) Type 1 entrapment. Women are much more likely to develop PS than men. The diagnosis is difficult in the past due to the lack of standardized diagnostic tests. Cases can present with symptoms attributable to PS. They report sciatica, paraesthesia, numbness, and episodic sharp pain in the perineal area, which is exacerbated on prolonged sitting, standing, and walking. Magnetic resonance imaging (MRI) scans of lumbosacral spine and lumbosacral plexus are usually normal. Their clinical symptoms can be misdiagnosed with urinary tract infection. The treatment with antibiotics has no effect on pain and paraesthesia. The urine cultures are negative, consultation with a neurosurgeon is requested due to associated sciatic pain. The compression of sciatic nerve and PN by PM is rare but possible. These symptoms can be misdiagnosed and mistreated. Nondisc sciatica is no longer a rarity with the easy availability of MRI for most patients with lumbago and sciatica. The awareness of possible association of Type 1 pudendal neuralgia with PS is necessary.