Orthopaedic surgery on the shoulder is amenable to pain control
using what is known as an interscalene block which is a type of
brachial plexus block. This
type of block is performed in the operating room at the time of
surgery, and involves an injection of long-acting local anaesthetic
drugs in the proximity of the nerves that supply the shoulder. The
site of injection is on the side of the neck, near the base. The
nerves are usually located using a
nerve stimulator, a
device that generates small impulses of electrical current. When the
tip of the needle comes close to the nerves, the electrical current
stimulates the nerves. This results in either a tingling sensation
that travels down the arm, an involuntary twitching of the muscles
of the arm or shoulder, or both.
Once the nerves have been located, the
anaesthetic solution is
injected, producing a block of painful sensations resulting from
surgery that usually lasts for most of the first day.
Many patients require additional pain medications to achieve good
control, but the amounts needed are substantially reduced after
interscalene block.
