Hi. This is my first post on the blog. I just had my lap band surgery on March 5th and have had this horrible left sided shoulder/neck pain. I first noticed the pain 2 days after surgery and it seems to be pretty consistent. It is on the top of my left shoulder and up into the left side of my neck. Some times it is worse than others. Massaging it makes it worse. Anyone else have this pain or know what to do for it or why it is caused?:wink2:

The pain is caused by pressure on the phrenic nerve. For some people it only lasts a short time. For me it lasted a couple months.

Here is some info I copied from another banster's post awhile ago:

Best explanation of left shoulder pain I've ever found.

If you woke up with a pain in your shoulder, you'd probably think something was wrong with your shoulder, right? Maybe you slept on it the wrong way, maybe you're a weekend warrior who threw the football a few too many times. In most cases, your hunch is probably right. Pain in the shoulder usually indicates an injury or disease that affects a structure in your shoulder, such as, say, your subacromial bursa or a rotator cuff tendon. Makes sense, doesn't it?

But you might be way off. Sometimes the brain gets confused, making you think that one part of the body hurts, when in fact another part of the body, far removed from the pain, is the real source of trouble. This curious (and clinically important) phenomenon is known as referred pain. For example, it's unlikely but possible that your shoulder pain is a sign of something insidious happening in your liver, gall bladder, stomach, spleen, lungs, or pericardial sac (the connective tissue bag containing the heart). Yup - conditions as diverse as liver abscesses, gallstones, gastric ulcers, splenic rupture, pneumonia, and pericarditis can all cause shoulder pain. What's up with that?

Neuroscientists still don't know precisely which anatomical connections are responsible for referred pain, but the prevailing explanation seems to work pretty well. In a nutshell, referred pain happens when nerve fibers from regions of high sensory input (such as the skin) and nerve fibers from regions of normally low sensory input (such as the internal organs) happen to converge on the same levels of the spinal cord. The best known example is pain experienced during a heart attack. Nerves from damaged heart tissue convey pain signals to spinal cord levels T1-T4 on the left side, which happen to be the same levels that receive sensation from the left side of the chest and part of the left arm. The brain isn't used to receiving such strong signals from the heart, so it interprets them as pain in the chest and left arm.

So what about that shoulder pain? All of organs listed above bump up against the diaphragm, the thin, dome-shaped muscle that moves up and down with every breath. The diaphragm is innervated by two phrenic nerves (left and right), which emerge from spinal cord levels C3, C4, and C5 (medical students remember these spinal cord levels using the mnemonic, "C3, 4, 5 keeps the diaphragm alive"). The phrenic nerves carry both motor and sensory impulses, so they make the diaphragm move and they convey sensation from the diaphragm to the central nervous system.

Most of the time there isn't any sensation to convey from the diaphragm, at least at the conscious level. But if a nearby organ gets sick, it may irritate the diaphragm, and the sensory fibers of one of the phrenic nerves are flooded with pain signals that travel to the spinal cord (at C3-C5). It turns out that C3 and C4 don't just keep the diaphragm alive; neurons at these two spinal cord levels also receive sensation from the shoulders (via the supraclavicular nerves). So when pain neurons at C3 and C4 sound the alarm, the brain assumes (quite reasonably) that the shoulder is to blame. Usually that's a good assumption, but sometimes it's wrong.

From:

Anatomy Notes: Referred pain