Parsonage–turner syndrome after interscalene block for diagnostic arthroscopic surgery of shoulder joint

leading to hypersensitivity of the damaged nerves to stretching or pressure.[1] This syndrome can present with sudden-onset pain radiating from the shoulder to the upper arm, followed by weakness and numbness. Subsequently, there is generally a phase in which there is no pain while resting but, with specific movements or positions, sudden sharp shooting pain can occur, which subsides within a couple of hours. Affected muscles become weak and atrophied, and in advanced cases, paralyzed.[2] The most common presentation is involvement of nerves of brachial plexus, but the nerves of upper and lower legs and feet, diaphragm or the vocal cords, skin and muscles of the abdomen, muscles of the face and ear and organ of Corti can also be affected.[3] Surgery, trauma, or exhausting exercise, infection, vaccinations, and treatments with blood products or immunotherapy could be predisposing factors. Although it is a well-documented entity with autosomal dominant variant, to our knowledge, there are few reported cases of PTS precipitated by interscalene block in a healthy adult in anesthesia literature. Tetzlaff et al.[4] have reported a case of idiopathic brachial plexitis after total shoulder replacement for osteoarthritis with interscalene brachial plexus block in a 65-year-old hypothyroid patient. Provisional diagnosis is based on thorough history and examination and appearance of a sudden and severe shoulder and upper arm pain, paralysis, and amyotrophy. Accurate diagnosis can be challenging, but nerve conduction velocity and imaging studies assist in the evaluation.[5] Although the mechanisms of this injury are unclear, the potential preexisting occult pathology of the peripheral nervous system may have predisposed him to development of a peripheral autoimmune injury leading to a brachial neuritis. Treatment is symptomatic and requires combination of a long-acting nonsteroidal anti‐inflammatory drug (NSAID) with long‐acting opioids for acute phase. A short therapy of oral prednisone along with immunoglobulin therapy has a favorable effect in some cases.[6] Later on, during the chronic phase of the disease, patient may require psychotherapy to cope with psychological trauma of chronic pain and chiropractic care or physiotherapy to regain function in the limb and to prevent contractures. Patients and physicians may misunderstand the persistence of pain and paresthesias in the early postoperative period to be a reflection of poor surgical sequelae or anesthetic complication. Sir,