Focal myositis is a rare disease associated with inflammatory changes invading the skeletal muscles and may be triggered by nerve lesion. We describe a case of 33-year-old woman who was diagnosed focal denervation myositis of piriformis and gluteal muscles associated with sciatic neuropathy because of severe uterine enlargement due to twin pregnancy misdiagnosed as lumbar herniated nucleus pulposus. MRI is one of the key diagnostic tools in the assessment of focal denervation myositis for differential diagnosis. Nonsteroidal anti-inflammatory drugs are commonly used for treatment of focal myositis. Spontaneous regression is obtained in numerous cases.

• 이승훈(충남대학교 의과대학 마취통증의학교실) | Seounghun Lee (Department of Anesthesiology and Pain Medicine, College of Medicine, Chungnam National University, Daejeon, Korea)
• 노찬(충남대학교 의과대학 마취통증의학교실) | Chan Noh (Department of Anesthesiology and Pain Medicine, College of Medicine, Chungnam National University, Daejeon, Korea)
• 홍부휘(충남대학교 의과대학 마취통증의학교실) | Boohwi Hong (Department of Anesthesiology and Pain Medicine, College of Medicine, Chungnam National University, Daejeon, Korea)
• 이선열(충남대학교 의과대학 마취통증의학교실) | Sunyeul Lee (Department of Anesthesiology and Pain Medicine, College of Medicine, Chungnam National University, Daejeon, Korea)
• 고영권(충남대학교 의과대학 마취통증의학교실) | Youngkwon Ko (Department of Anesthesiology and Pain Medicine, College of Medicine, Chungnam National University, Daejeon, Korea)
• 김여정(충남대학교 의과대학 마취통증의학교실) | Yeojung Kim (Department of Anesthesiology and Pain Medicine, College of Medicine, Chungnam National University, Daejeon, Korea) Corresponding author