Causes of Pain in Shoulder from Car Accident
There are two main causes of pain in the shoulder after a car accident. The most common cause is bracing with the arm extended. For drivers, this happens because the driver grips the steering wheel tightly on impact. The arm muscles tense to resist the forces of the impact but the shoulder is not strong enough to withstand the compression. For passengers, the mechanism of injury is similar, but the steering wheel is not involved. Instead, the passenger braces the hand on something at the front like the dashboard or a car seat.
The other main cause of shoulder pain after a car accident is a whiplash shoulder injury. Apparently, the rapid whipping back and forth in a car accident can cause shoulder injuries. According to one study, 83% of shoulder injuries from car accidents occur to the seatbelt.
Shoulder Anatomy
The shoulder is probably the most complex joint in the human body. In order to understand shoulder injury from a car accident, you need to know a little bit about shoulder anatomy.
The shoulder is the part of the body at the end of the upper arm that allows the humerus bone to connect to the upper torso at the scapula (shoulder blade) and clavicle. Two shoulder joints create the movement of the arm in many different directions. These joints are held together by a series of muscles and tendons called the rotator cuff.
The acromioclavicular joint at the top of the shoulder blade connects the clavicle (the collar bone) to the acromion. The subacromial bursa beneath the acromion is a small membrane that lubricates the rotator cuff tendons so they move smoothly.
The glenohumeral joint lower down on the scapula connects the humerus bone of the upper arm. It works because the round ball at the end of the humerus fits into the shallow socket called the glenoid. The joint capsule holds the ball of the humerus to the glenoid.
Types of Shoulder Injury from Car Accident
There are many different types of shoulder injuries that can occur from a car accident. Below are the most common shoulder injuries and their treatments:
Shoulder Impingement Syndrome After a Car Accident
The space below the acromion and above the glenohumeral joint is called the subacromial space. The subacromial bursa and the supraspinatus tendon of the rotator cuff are located within the subacromial space. Trauma from a car accident can stretch the rotator cuff muscles and or cause swelling. The swelling within the subacromial space can make less room available in the space for the tendon and bursa to move. This can squeeze the supraspinatus tendon and the bursa. Bone spurs at the bottom of the acromion can also reduce the amount of room for the tendon and the bursa. All of this can put pressure on the tendon and bursa causing shoulder pain. The muscle can then begin to fray or tear and the bursa can swell even more.
Symptoms of Impingement Syndrome
Common symptoms of impingement syndrome after a car accident include:
- Pain in the shoulder when extending the arm above the head
Shoulder pain when reaching behind the back
- Shoulder muscle weakness
Diagnosing Shoulder Impingement Syndrome
The first step to figuring out if shoulder pain is from shoulder impingement syndrome is a medical history and physical exam. This will allow your doctor to pinpoint the location of the shoulder pain. Next, the doctor will perform an impingement test. This involves raising your arm above the shoulder to see if it reproduces the shoulder pain. X-rays can be taken to rule out arthritis. In addition, an MRI may be used to clearly see the rotator cuff swelling and or bone spurs. Lastly, a physician may inject a local anesthetic into the bursa to see if that eliminates the pain.
Shoulder Impingement Syndrome Treatment
Initial treatment for shoulder impingement syndrome involves resting the shoulder, ice packs, and anti-inflammatory medication. If the pain continues, the doctor may inject cortisone into the subacromial joint space. As the swelling and shoulder pain reduces, physical therapy can be used to regain strength and help retrain the shoulder to move properly.
If the pain continues, the next step may be surgery to remove bone spurs, the front of the acromion, and or part of the bursa. Surgeries performed include:
- Subacromial decompression
- Arthroscopic acromioplasty
Rotator Cuff Tear After a Car Accident
Four muscles along with their connective tendons make up the rotator cuff. The four connective tendons are called the supraspinatus tendon, the subscapularis tendon, the teres minor, and the infraspinatus tendon. These muscles and their tendons help allow the arm to move in so many different directions. Trauma from a car accident can cause any of these to tear and become painful.
Symptoms of Rotator Cuff Tear
Common symptoms of a rotator cuff tear after a car accident include:
- A crackling feeling when moving your shoulder
- Pain when lifting and lowering the arm
- Pain or a dull ache deep in the shoulder when resting
- Pain at night while trying to sleep, especially when lying on the affected shoulder
- Weakness in the shoulder when moving the arm in specific directions
Diagnosing Rotator Cuff Tear
The MRI is the best way to diagnose a rotator cuff tear. There are times when a rotator cuff tear is not visible on the MRI image but later found during surgery. But most of the time rotator cuff tears appear on MRI.
Rotator Cuff Tear Treatment
Small rotator cuff tears can heal. Initial treatment may include resting the shoulder and or wearing a sling. After some of the inflammation goes away, physical therapy may be used to stretch and strengthen shoulder muscles. In addition, anti-inflammatory medication may be prescribed and or corticosteroids may be injected directly into the shoulder. If the shoulder does not heal within 3 months and or the tear is greater than 3 centimeters, rotator cuff repair surgery may be necessary.
Labral Tear after a Car Accident
The labrum is a rubbery cartilage material that is attached to the rim of the shoulder socket. It helps keep the ball of the humerus bone of the upper arm in place. When this cartilage tears, it’s called a labral tear. It is also called a labrum tear. Common types of labral tears are called SLAP tears and Bankart tears.
Symptoms of a Labral Tear
Common symptoms of a labral tear after a car accident include:
- Pain with movement especially movement overhead
- An unstable feeling in the shoulder
- Loss of strength
- Reduced range of motion
- A grinding, locking, or catchy feeling
Diagnosing Labral Tear
Like a rotator cuff tear, the best way to diagnose a labral tear is with an MRI.
Labral Tear Treatment
Labral tear treatment is similar to rotator cuff tear treatment. Rest, anti-inflammatory medication followed by physical therapy. If this does not help, then the next step is labral tear repair surgery.
Shoulder Dislocation After a Car Accident
A shoulder dislocation occurs when the ball at the end of the humerus in the upper arm pops out of the socket. This can also lead to labral tears
Shoulder Dislocation Symptoms
Common symptoms of shoulder dislocation include:
- Severe constant shoulder pain
- Bruising and swelling of the shoulder and upper arm
- Difficulty moving the arm
- A feeling the arm is out of place
- Weakness or numbness in the arm, neck, hand, and fingers
- Muscle spasms in the shoulder
Diagnosing Shoulder Dislocation
The standard for diagnosing shoulder dislocation is an x-ray.
Shoulder Dislocation Treatment
When the shoulder is dislocated, the muscles of the shoulder will hold it out of place. To correct the problem, a doctor will pull the arm in certain directions to get the shoulder to pop back into place. This is not something you should try yourself. If it is not done properly, the act of trying to relocate the shoulder can further damage the joint.
Shoulder Fracture After Car Accident
A shoulder fracture happens when any of the bones that make up the shoulder break. There are three different types of shoulder fractures. They are a clavicle fracture, proximal humerus fracture, and a scapula fracture.
Shoulder Fracture Symptoms
The most common symptoms are:
- Pain at the point of the fracture
- Swelling
- Tenderness
- A deformity at the sight of the fracture
- Bruising
- Pain at the sight of the fracture with movement
Diagnosing Shoulder Fracture
Shoulder fractures are easily diagnosed with an x-ray.
Shoulder Fracture Treatment
When the bone has a crack or the fractured bone remains in place (a non-displaced fracture), the treatment is usually a sling until the fracture heals.
When the bone is out of place and or there are a lot of fracture fragments (a displaced fracture) surgery may be required to put the bones back in place with wires, pins, plates, or screws.
Car Accidents and Degenerative Shoulder Changes
As we age, our shoulders can show signs of wear and tear. In fact, impingement syndrome, bone spurs, rotator cuff tears, and even labral tears can all occur over time as we age. This is commonly called degenerative changes in the shoulder. Sometimes these degenerative changes are painful. However, other times they are not painful until some traumatic event like a car accident occurs. When this happens, the trauma can cause inflammation that can make impingement syndrome painful. Trauma can also make a degenerative rotator cuff tear or labral tear increase to the point it is painful.
Insurance companies often claim impingement syndrome, rotator cuff tears, and labral tears are caused solely by degenerative changes and not the trauma from a car accident. In fact, they routinely pay certain defense medical doctors lots of money to testify to juries that people legitimately injured by the trauma from a car accident are really just suffering from degenerative changes. A good injury lawyer can usually overcome this argument by getting the support of the injured persons treating doctors and by cross-examining the defense medical doctor.
