Outpatient orthopedic shoulder surgery: Your pain relief options

The shoulder is the body’s most flexible joint. While this flexibility allows you to move your arm in all different directions, it also makes the shoulder particularly vulnerable to injury. In 2010, nearly 11.5 million people visited their doctor for shoulder problems.^[1] Common shoulder injuries include tears in the rotator cuff muscles (muscles around the shoulder), partial or complete dislocation of the shoulder socket, and collarbone fracture. In many cases, nonsurgical treatment options, such as physical therapy, are enough to relieve symptoms, but sometimes surgery is needed. In severe cases of osteoarthritis (a form of arthritis affecting the cartilage of your joints) and in situations of severe injury, such as fracture of the upper arm bone (humerus), a partial or total surgical replacement of the shoulder joint is necessary. Hundreds of thousands of these procedures, known as shoulder arthroplasty, have been performed for osteoarthritis since the early 2000s,^[2] and this number seems to be on the rise.^[3]

Many shoulder injuries can be addressed through less invasive shoulder procedures done through a small camera placed through very small incisions. This procedure is known as shoulder arthroscopy and  is often used to treat a frozen or dislocated shoulder, rotator cuff injuries, or a fracture of the shoulder blade (scapula).^[15] Most of these surgeries are performed on an outpatient basis. Pain after shoulder surgery is completely “normal” and to be expected. Fortunately, you have a number of options for pain relief (“analgesia”). Your physicians will likely use different types of pain medicines around the clock, known as multimodal analgesia, to provide ongoing pain relief not only during the procedure, but also through your recovery.^[4]

What is the anatomy of the shoulder?

In order to understand your options for pain relief following shoulder surgery, it’s important to first understand the anatomy of the shoulder. The shoulder contains a number of bones, joints, muscles, and ligaments, which all work together to make the many shoulder movements possible.^[5] The shoulder joint, one of the body’s largest and most complex, is formed by the humerus and scapula, which fit together like a ball and socket. Another major joint in the shoulder area is the acromioclavicular joint, which joins the collarbone (clavicle) to the acromion, which is part of the scapula. An additional important component of the shoulder is the rotator cuff, a group of muscles and tendons that supports the shoulder and provides its wide range of motion.

How does shoulder pain occur? 

Pain signals travel through nerves, the body’s extensive “information highway.”  

Shoulder pain is primarily sent to the brain through a group of nerves known as the brachial plexus. These nerves start in the spinal cord and travel through the neck and down the arm.

What is the difference between general and regional anesthesia?

General anesthesia is a state of unconsciousness during which a patient does not feel pain or any other sensations in the body throughout the procedure.^[7]

Regional anesthesia involves putting only a certain part of the body to sleep. This is done by putting numbing medicine (similar to the one used at the dentist office) around the nerves in this part of the body. This is commonly known as a “nerve block.”

Shoulder surgery patients commonly receive general anesthesia. In these cases, nerve blocks are still helpful to block pain signals during surgery, allowing patients to wake up from surgery with little to no pain. Patients recover more quickly after surgery because they receive fewer opioids (a type of pain reliever) during surgery.

Alternatively, patients may remain completely awake for the surgery or may be a given a sedative. Depending on the strength of the sedative used, the patient may feel awake and relaxed but able to follow instructions. Or, the patient may sleep throughout the procedure and not remember it afterwards.

What is a peripheral nerve block?

Peripheral nerve blocks are a type of regional anesthesia that block the path of pain signals from specific nerves. They are commonly used to provide pain relief during and after shoulder surgeries. Nerve blocks can be administered either as a single injection or in a continuous fashion through the use of a thin tube called a catheter. The catheter is placed near the target nerve bundle. Continuous infusions are used when higher levels of pain are expected, and they may provide longer periods of pain relief. 

Nerve blocks are done using one of two techniques: nerve stimulation or ultrasound guidance. Nerve stimulation and ultrasound guidance can be used separately or together to properly do your nerve block.^[8] During nerve stimulation, your anesthesiologist applies very small and short pulses of electrical current through a small needle to stimulate a nerve. He or she then watches specific muscles for twitching, which indicates that the needle is close to the nerve. With the ultrasound guidance method, your anesthesiologist will use ultrasound to see the group of nerves supplying the shoulder and will inject numbing medication around them, numbing only your shoulder. He or she may also insert a catheter next to these nerves if needed.^[5]

What types of nerve blocks are available?

Interscalene Block

An interscalene nerve block is the most common type of nerve block used in shoulder surgeries^[5] and is the best way to block the first part of the brachial plexus, where the nerves to the shoulder come from.^[9] You will lie on your back with your back slightly elevated and your head turned away from the shoulder that will be receiving the block. You may be asked to lift your head off of the operating table to help the anesthesiologist identify muscle landmarks that will guide the placement of the block. Alternatively, you may be asked to lie on your side to receive the block.

After cleaning the area above the collar bone with an antiseptic solution, your anesthesiologist will apply a local anesthetic to numb the area. He or she will then determine the precise location for the needle using either nerve stimulation, ultrasound guidance, or both.

Following injection of the numbing medicine near the nerve bundle, your surgical team will wait to make sure the medicine has spread into the area before beginning your procedure. A catheter may also be placed next to the nerves in this area so that you can receive additional infusions of the local anesthetic after surgery to help control your pain. The need for a continuous catheter will be determined by you, your anesthesiologist, and your surgeon.^[10]

Supraclavicular Block 

The supraclavicular block can be also used in shoulder surgeries, with similar success rates and side effects to an interscalene block.^[11][12][13] It is placed while you are lying flat on your back with your head turned away from the shoulder that will be blocked. Following the application of an antiseptic solution and numbing up your skin, your

anesthesiologist will use ultrasound guidance to place the block. Nerve stimulation may or may not also be used. The supraclavicular block maybe applied as a single injection or a catheter to allow for additional doses or continuous infusion of the local anesthetic for postoperative pain relief. After the block has been done, your surgical team will wait for the medication to take effect before beginning your surgery.

Suprascapular Nerve Block

An alternative, effective form of regional anesthesia used in shoulder surgeries is the suprascapular nerve block.^[14] A suprascapular nerve block is performed while you are in a sitting position or on your side. After cleaning the region with an antiseptic solution, your anesthesiologist will inject a local anesthetic to numb the area before performing the block. He or she will then use an ultrasound machine to see the nerve and inject numbing medicine around it.

Axillary Nerve Block

An axillary nerve block is often done in combination with a suprascapular nerve block to better relieve pain after surgery, with results that may be similar to an interscalene nerve block.^[16][17][18] For this block you will also be in the sitting position or on your side. As with the other nerve blocks, the skin around the injection site will be cleaned and your surgery will proceed only after the medicine has taken effect.

What are the benefits of nerve blocks?

Nerve blocks have several advantages in shoulder surgery. First, nerve blocks provide better pain relief after surgery than the combination of general anesthesia and systemic pain-relieving medications such as opioids that are given after surgery.^[7] This is because pain relief provided by nerve blocks is much more specific to the location of the pain. You will also need lower doses of opioids after surgery to control your pain. Opioids have a number of side effects, which are discussed below, so minimizing their use is important. Regional anesthesia provides greater muscle relaxation than general anesthesia. You will also need less anesthesia for the surgery because your shoulder is totally numb during and after the procedure.^{[7 ]} That means that you will have less pain, your recovery will be quicker, and your rehabilitation will be easier.

If you happen to receive a block and sedation for surgery instead of receiving general anesthesia, you may avoid many of the side effects and complications associated with general anesthesia, including feeling sick to your stomach or throwing up after anesthesia, commonly known as postoperative nausea and vomiting (PONV).

What are the drawbacks of opioids?

Opioids such as morphine and fentanyl are frequently used around the time of surgery to treat postoperative pain. Unfortunately, opioids in all forms can cause a number of side effects, including potentially life-threatening breathing problems, as well as nausea, vomiting, and a disruption of normal bowel function that can lead to constipation, among others.^[20] In addition, the sedating effects of opioids can lead to higher rates of falls and other injuries and affect a person’s ability to drive and get back to normal following surgery.

Another problem with opioids is their high potential for dependence and abuse. Prescription opioid abuse is a very serious and growing national problem. According to the Centers for Disease Control and Prevention (CDC), nearly 200,000 people died from to prescription opioid overdoses from 1999 to 2015, and more than 1,000 people are treated in emergency rooms every day for using prescription opioids incorrectly.^[21]

Patients who take opioids after surgery are at high risk for long-term opioid use. A recent study of nearly 40,000 surgical patients revealed that 6 percent refilled an opioid prescription more than 3 months after surgery, long after the time period when these drugs are needed to control postoperative pain.^[22] This rate was not different between those who had undergone minor and major surgeries, suggesting that the opioid use was not due to surgical pain but other factors instead.  

Summary

Shoulder surgery can be painful, but you have a number of options when it comes to pain relief during and after your procedure. Regional anesthesia (peripheral nerve blocks) has a number of advantages over general anesthesia and using postoperative opioids alone. Talk to your surgeon and anesthesiologist to determine what pain relief options are best for you based on your individual medical situation.

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