Pronator Teres Syndrome
Do you have a painful forearm or weird sensations in your thumb and pointer finger? Maybe your forearm, wrist, and elbow have been aching. A quick online search for symptoms yields dozens of results for painful hand, wrist, and elbow conditions, making fact-finding confusing. Your pain and discomfort may partially match common wrist complaints like carpal tunnel syndrome, hand tendonitis, elbow pain, and other related conditions, or your symptoms don’t seem to fit any single situation -- making it hard to tell what exactly is going on with yourself. One lesser-known condition that causes finger tendon and forearm discomfort is called pronator teres syndrome, and this culprit for finger, hand, wrist, and forearm pain lies close to the elbow. Pronator teres syndrome imitates other conditions; however, it is discernable.
But what exactly is pronator teres syndrome, and how can you tell pronator teres syndrome from other related wrist and hand conditions?
What is pronator teres syndrome?
The elbow is a structure connecting bones, ligaments, connective tissues, the elbow joint, several muscles, bursa (fluid-filled sacs designed to absorb forces), and nerves. Repetitive or excessive movement causes injury and damage to these structures.1 With this syndrome, a specific muscle is the victim: the pronator teres muscle of the forearm.2
Excessive or repetitive movement can have many causes: carpentry, assembly line work, basketball, plumbing, weightlifting, mechanic work, or any repetitive movement that causes the wrist to bend and the forearm to go palm-down. These excessive movements contribute to stress and strain on the pronator teres. This muscle lives in the upper forearm and has two ends or heads. When it becomes swollen or inflamed, it can affect other structures nearby, such as the median nerve of the forearm and wrist.2 Additionally, the median nerve can also be compressed by a local ligament coming off the bicep muscle: the lacertus fibrosis.
The median nerve is one of three nerves that supply our upper extremity. This nerve begins in the upper arms and extends into the wrist and fingers. When the pronator teres muscle compresses this nerve, it creates aching in the forearm and wrist, possible muscle weakness, and changes in sensation to the thumb and index finger.3
Pronator teres syndrome is like carpal tunnel syndrome, defined as compression of the median nerve at the wrist.3,4 However, pronator teres syndrome affects both the hand and the forearm, whereas carpal tunnel syndrome largely affects the wrist and hand only. Common signs that the median nerve is being entrapped at the elbow include the following3,4:
Aching discomfort in the forearm and tenderness on palpating (pressing) into the pronator teres muscle
Tingling sensation in the forearm, palm, and/or fingers (including the thumb)
Numbness in the forearm, hand, and/or fingers (including the thumb)
Pain and discomfort in the forearm, hand, and/or fingers (including the thumb)
Muscle weakness in the forearm, wrist, and/or fingers (including the thumb)
With pronator teres syndrome, there may not be a history of trauma or injury associated with symptoms. Instead, the symptoms may come on gradually and worsen over time.3,4
Who gets pronator teres syndrome?
Several factors can put people at higher risk of developing pronator teres syndrome.4 These include:
People employed in occupations that increase the bulk of the pronator teres muscle such as mechanics, plumbers, and athletes in weightlifting or racket sports
People with a history of trauma to the elbow resulting in restrictive bands of scar tissue or fibrous tissue in the forearm
The typical age of onset is in the fifth decade, and the condition is more common in women than men. Patients with metabolic disorders like diabetes, alcoholism, or hypothyroidism are predisposed to this condition.5
How do I know if I have pronator teres syndrome?
Symptoms of pronator teres include aching pain and discomfort on the volar (front) side of the forearm with sensory disturbances along the thumb, pointer finger, and even the palm of the hand. The pain may span the lower arm. You may notice discomfort when turning your wrist to go palm-down (pronation), or this maneuver may make your pain and changes in sensation worse.2,3,4
Is pronator teres syndrome essentially the same thing as carpal tunnel syndrome?
Not really. Although the symptoms may be similar, the causes are very different and require different treatment approaches. Compression of the median nerve causes carpal tunnel syndrome by inflamed tendons where the wrist meets the hand; pronator teres syndrome is compression of the median nerve near the elbow due to hypertonic (tight) muscles, muscle adhesions, and/or the presence of scar tissue or fibrous tissue that compress the nerve.2,3
How is pronator teres syndrome treated?
For mild to moderate cases of pronator teres syndrome, conservative treatments like chiropractic care and rehabilitation are the first line of defense to attempt resolution of the condition. These non-surgical methods may include one or more of the following:
Rest from the inciting activity
Anti-inflammatory pain medications
Forearm splinting to prevent rotating
Targeted exercises and rehabilitation
Severe cases may require a minimally invasive surgical intervention to relieve the pressure on the median nerve. Thankfully, most cases don’t need it.
Source: Chiropractic Success Academy
1. Chumbley EM, O'Connor FG, Nirschl RP. Evaluation of overuse elbow injuries. Am Fam Physician. 2000 Feb 1;61(3):691-700.
2. Plancher KD, Peterson RK, Steichen JB. Compressive neuropathies and tendinopathies in the athletic elbow and wrist. Clin Sports Med. 1996 Apr;15(2):331-71.
3. Posner MA. Compressive neuropathies of the median and radial nerves at the elbow. Clin Sports Med. 1990 Apr;9(2):343-63.
4. Howard FM. Compression neuropathies in the anterior forearm. Hand Clin. 1986;2:737-745.
5. Tetro AM, Pichora DR. High median nerve entrapments. An obscure cause of upper-extremity pain. Hand Clin. 1996;12:691-703.
6. Dididze M, Tafti D, Sherman Al. Pronator Teres Syndrome. [Updated 2021 Aug 3]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2021 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK526090/