Median nerve block is widely practised, avoiding general anaesthesia in a number of cases and producing excellent post-operative analgesia in orthopedic surgery. Even realised by experienced anaesthetists,a failure rate of 5-15% is noticed. The principal aim of the study is to observe the local anesthetic solution diffusion after a conventional median nerve block technique using neurostimulation. The secondary objective is to compare diffusion and of block efficacy..

Inclusion Criteria:

• Patients undergoing elective hand surgery requiring a median block nerve.

Exclusion Criteria:

• age lower than 18 years
• pregnancy
• contraindication to nerve block
• inability to read, write or speak French
• mental illness.

primary care clinic