Pronator teres syndrome occurs when the median nerve, which passes between two parts of the pronator teres muscle in the arm, gets trapped. As a result, there is usually pain and numbness in both the forearm and hand. Sometimes, the symptoms of pronator teres syndrome get mistaken for carpal tunnel syndrome. Although we can’t say for certain why, people between the ages of 40 and 50 are more likely to experience PTS.
Anatomy of pronator teres
The pronator teres muscle is located on the palm side of the forearm just below the elbow. Its job is to rotate the forearm palm-down. This is actually called pronation.
The PT muscle has two heads: the humeral head and the ulnar head. They connect the ends of the humeral head (bone of the upper arm) and the ulnar head (bone stretching from the forearm to the smallest finger). It is believed that pronator teres syndrome can be due to neurogenic pain in the wrist. This is usually due to over-activity of the pronator teres muscle. The over-activity leads to the median nerve becoming entrapped. Repetitive throwing or turning is one way a person might get pronator teres syndrome.
Prevalence of pronator teres syndrome
In 2016, a study looking at the prevalence of pronator teres syndrome and carpal tunnel showed that of those who have PTS, 18 percent also suffer from carpal tunnel syndrome. Eight out of 17 patients had severe carpal tunnel, while seven had moderate and two had mild. Age did not seem to make a significant difference in the study. The authors of the study believe pronator teres syndrome should be considered a possibility among those who suffer from carpal tunnel syndrome, especially in cases where carpal tunnel is severe.
What causes pronator teres syndrome?
As we established earlier, pronator teres syndrome is due to compression of the median nerve in a specific section of the forearm. It is usually from excess pressure being put on the nerve by the pronator teres muscle. Below are some more causes of pronator teres syndrome.
- Overuse – Constant use of the pronator teres muscle or repetitive hand movements that are associated with certain jobs, such as carpentry or sports with overhand movements, can trigger entrapment of the median nerve.
- Pressure – Increased pressure on the median nerve by other arm structures, such as ligaments, hardening or thickening of fibrous tissues, as well as some types of structural abnormalities, can cause the median nerve to become trapped.
- Excessive exercise – Using the muscles in the forearm frequently for strenuous workouts can cause pronator teres syndrome symptoms.
- Fibrous bands – Fibrous bands can sometimes form within the pronator muscle, leading to compression of the median nerve.
- Trauma – An injury or trauma to the forearm can cause PTS
- Tumors – Compression on the median nerve can be the result of tumors
- Scar tissue – Compression on the median nerve due to scar tissue can also cause PTS.
What are the symptoms of pronator teres syndrome?
The median nerve provides us with the sensation of touch in the skin of the thumb, palm, bones of the wrist, as well as the middle, index, and half of the ring finger. It is easy to understand how compression of this nerve can lead to symptoms in the forearm, elbow, and hand. The following are typical pronator teres syndrome symptoms:
- Tingling sensation in palm, forearm, and fingers
- Pain in palm, forearm, and fingers
- Stiff fingers or limited finger movement
- Muscle tenderness, especially when touched
- Forearm pain
- Weakness in thumb
- Weakness in forearm and wrist
Those who complain about night pain are more likely to be suffering from carpal tunnel syndrome.
Diagnostic test for pronator teres syndrome
PTS can be diagnosed with a pronator teres syndrome test. A doctor will simply ask the patient to stand and then fold their arm at the elbow to make a 90-degree angle. The physician will then use a hand to support the elbow and slowly turn the forearm with the other hand to contract the pronator teres muscle. If there is discomfort and pain during this exercise, the patient may be suffering from compression of the median nerve between the heads of the pronator muscle.
There are other exercises, including one in which the elbow is flexed at 90 degrees and the clinician grasps the patient’s hand in a handshake position. The clinician forces the patient to contract the pronator muscles and extends the patient’s elbow. If this causes pain, there is a chance of median nerve compression.
Typically during a pronator teres syndrome test, pain, tingling, numbness, and burning can lead to a positive diagnosis.
Pronator teres syndrome vs carpal tunnel syndrome
It can be helpful to understand the difference between pronator teres syndrome versus carpal tunnel syndrome. With pronator teres syndrome, there is pain and tingling in the palm of the hand, but with carpal tunnel, the tingling and numbness are in the wrist as well as the thumb and the first two and a half fingers. So while both conditions can include pain, tingling, numbness, and even a burning sensation, those symptoms are experienced in different places.
With pronator teres syndrome, there is often aching pain that is localized to the forearm and sometimes complete loss of sensation to the palm of the hand. People who suffer from carpal tunnel can go for short periods of time without pain, but often have difficulty sleeping at night because sharp pain in their wrist or fingers wakes them up.
Pronator teres syndrome treatment
In many cases, massage therapy is used as a pronator teres syndrome treatment. The therapy helps to lengthen and release the muscles and prevent the condition from getting worse. It is important though for the problem areas to be correctly identified before proceeding with massage therapy. Massage techniques can work on stubborn tension in the muscle, but regular stretching will further assist and prevent PTS from returning. Many people who have pronator teres syndrome are encouraged to stretch their arm gently and frequently throughout the day.
One way to do so is by standing with your back toward the inside of a door frame and extending your left arm straight above the midpoint between your hip and shoulder. Hold the doorframe with your left hand, keeping the thumb pointing down and rolling your biceps upwards. You should feel a stretch in the front part of your arm in the elbow and forearm area.
Pronator teres syndrome physical therapy is also an option, but should be considered upon a doctor’s recommendation. Physiotherapy and pronator teres exercises can bring some people a lot of relief. Adding ice therapy to the mix and elevation of the arm can also be helpful, especially in cases where the syndrome is related to an injury or trauma.
There are situations where pronator teres syndrome surgery is required. The surgery includes alleviating the pressure on the median nerve. Some doctors may also prescribe corticosteroid injections that go right into the pronator muscles. Painkillers and anti-inflammatories are taken by some people who suffer from PTS as well. Some alternative treatments such as acupuncture and electrotherapy have proved helpful for pronator teres syndrome.
Most people recover from PTS with the use of varied therapies in about four months, but sometimes, it can take a little longer.
Each case of pronator teres syndrome can be slightly different. Some people experience really mild symptoms that they don’t pay much attention to. These symptoms can progress to something more debilitating. The sooner pronator teres syndrome is diagnosed and treated the less chance you have of losing any mobility.
Massage and Exercises for Pronator Teres
Massage and exercise can help alleviate pronator teres. Massages should focus on the pronator teres muscle to alleviate compression of the median nerve. This type of massage should be completed by a trained professional. The massage therapist will lengthen the muscle along with draining tension of tight muscles.
An effective stretch for pronator teres is to stretch your arm gently and frequently throughout the day. A forearm pronator stretch targets not only the pronator teres as well as the brachialis and brachioradialis. To complete this stretch, stand with your back toward the inside of the door frame and extend your left arm straight above the midpoint between your hips and shoulders. Hold the doorframe with your left hand with your thumb in the downward position and your biceps upward. Hold this position between 10 and 30 seconds and repeat with the other arm.
Other exercises that can help improve pronator teres include incidental exercises and isolation exercises.
Incidental exercises include body-weight exercises like pull-ups, neutral-grip pull-ups, reverse-grip pull-ups, or inverted rows. Weight-lifting exercises include bent-over rows, single-arm rows, lat pulldowns, and low pulley rows. To target the biceps, try barbell and dumbbell curls.
Isolation exercises work to help you rotate your forearm. For example, grab a dumbbell with your thumb against the inner surface. Sit on a bench or chair, bend your arm, and place your upper arm on the backrest with your thumb facing upward. Rotate the dumbbell so your thumb points downward then return back to start. Complete this a few times.
Each case of pronator teres syndrome can be slightly different. Some people experience really mild symptoms that they don’t pay much attention to. These symptoms can progress to something more debilitating. The sooner pronator teres syndrome is diagnosed and treated the less chance you have of losing any mobility.