Posterior Tibial Nerve Schwannoma in the Popliteal Fossa: A Case Report

Author(s): Luis Lopez-Gonzalez, Daniel Pecos-Martin, Mª Teresa Gomez-Gonzalez, Samuel Fernandez-Carnero, Tomas Gallego-Izquierdo

Schwannomas are uncommon disorders of peripheral nerves sheaths, presenting with particular neuropathic manifestations that are often misdiagnosed or undiagnosed. We offer a case report of a 36-year-old patient with an untypical schwannoma in the tibial nerve, causing long-lasting and increasingly exacerbated pain, misdiagnosed as a meniscus tear. The worsening symptoms, including hyperalgesia, allodynia and hypersensitivity, raised suspicion of malignancy. The patient underwent an ultrasound examination, where a compressive neuropathy was suspected. Finally, the presence of a large benign schwannoma was confirmed by magnetic resonance imaging. The tumour mass was excised and this gave way to a total and rapid relief of symptoms.