Change of practice in the department (Nerve stimulation technique abandoned)

Brachial plexus injury after shoulder surgery with continuous interscalene block is 2.4% at 1 month and 0% at 6 months, but may be higher with a systematic postoperative neurological examination. Indeed, femoral neuropathy after anterior cruciate ligament reconstruction is 24% at 6 weeks in a cohort of 20 consecutive patients systematically screened with an electromyogram. Brachial plexus injury may be the consequence of the surgery (direct lesion by traction) or the continuous interscalene block. The goal of this study is to define the etiology of this postoperative neuropathy.

Rotator cuff surgery is associated with moderate to severe postoperative pain. Among different analgesic strategies, continuous interscalene block is reported to be an efficient method, reducing opioid consumption and allowing rapid rehabilitation; however, patients may develop a transient neuropathy after surgery, which could have a significant impact on active patients. This study is designed to compare the incidence of brachial plexus injury in two groups of patients: one with a continuous interscalene block, and one with a patient control analgesia of morphine (self-iv administration of morphine). All patients will have a clinical neurological exam with a preoperative electromyogram in order to rule out a pre-existing neuropathy. Another clinical neurological exam with electromyogram will be performed between 4 and 6 postoperative weeks and, if pathological repeated at 6 months, 9 months and 12 months. The surgery will be done under general anesthesia for all patients.

Inclusion Criteria:

• patients planned for rotator cuff repair
• ASA 1, 2 and 3
• age 16 years and more

Exclusion Criteria:

• peripheral neuropathy
• pre-existing brachial plexus injury
• diabetes mellitus
• alcoholism
• drug addiction