Obturator nerve block as a clue to the diagnosis of focal spinal metastases of gastric cancer - a case report

Compression of the obturator nerve can result in severe, opioid-resistant pain experienced by a patient in the inner part of the thigh. In the case we describe here, compression of the nerve roots by vertebral metastasis resulted in nerve oedema and impingement at the place where the nerves normally pass through the narrow space in the obturator canal close to the pubic bone. Injection at this site with bupivacaine and methylprednisolone resulted in only a few hours of pain relief, which suggested more “central” involvement. An MRI of the spine revealed a focal bony deposit at L2 and radiotherapy was able to control the pain within few days. This case shows how a careful diagnosis of pain may lead to specific pain therapy and allow the decrease of the toxicity of drugs, especially opioids, which may be poorly tolerated by patients with neuropathic pain.Compression of the obturator nerve can result in severe, opioid-resistant pain experienced by a patient in the inner part of the thigh. In the case we describe here, compression of the nerve roots by vertebral metastasis resulted in nerve oedema and impingement at the place where the nerves normally pass through the narrow space in the obturator canal close to the pubic bone. Injection at this site with bupivacaine and methylprednisolone resulted in only a few hours of pain relief, which suggested more “central” involvement. An MRI of the spine revealed a focal bony deposit at L2 and radiotherapy was able to control the pain within few days. This case shows how a careful diagnosis of pain may lead to specific pain therapy and allow the decrease of the toxicity of drugs, especially opioids, which may be poorly tolerated by patients with neuropathic pain