The late diagnosis of nerve injuries following interscalene block and shoulder surgery

Abstract

Objectives: Interscalene blocks are commonly performed with the shoulder surgery, nerve injuries are reported to have the prevalence of 14% at 10 days postoperatively. While clinicians may be aware of the associated risk of nerve injury from either the surgery or the block, they may not recognize these nerve injuries. Our objectives were to determine factors contributing to injury and late referral. Methods: We searched our peripheral nerve injury database to identify a consecutive series of nerve injuries-associated with interscalene nerve block and the shoulder surgery. The identified cases were subject to clinical review and a review of the medical records including the consent form, anesthetic records, operation note, and the neurophysiology records. Results: Six cases of nerve injury were identified during a 24-month period. Half the patients experienced a delay of >6 months from injury to review, despite the documentation of persisting sensory and motor dysfunction. Regional anesthesia technique was not uniform. All patients required a specialist treatment from a regional peripheral nerve injury service. Conclusions: Clinicians should be aware that prolonged block duration is a feature of the potential nerve injury. The presence of a Tinel sign, autonomic dysfunction, and nerve pain in the distribution of the injured nerve are features suggesting nerve injury. Orthopedic surgeons should be able to recognize the nerve injury and seek early referral to the appropriate specialists. Where doubt exists, the patient should be referred for an urgent review by a peripheral nerve injury specialist.