What Is Reflex Pain?

Reflex pain is a complex condition that occurs when the body’s pain withdrawal reflex fails to disappear long after the triggering event.  The neurological phenomenon, known as the withdrawal reflex, occurs when the body executes a chain of reactions to remove an affected body part from painful stimuli. For example, after sustaining a strain or other injury, the body’s natural response is to protect itself from further injury. During this process, the body’s reflex muscle in the injured area tightens and acts as a splint to protect that specific body part.

The reflex feels like a muscle spasm and typically disappears over time. However, in the case of reflex pain, the body fails to break out of this compensatory pattern of persistent pain. Reflex pain can occur in many areas of the body, and as the muscles attempt to overcompensate to handle this prolonged pain, secondary injuries often develop. For example, reflex pain in the ankle may result in biomechanical problems in other areas, such as the hips and back as the patient attempts to avoid range of motion in the ankle.

Most patients who are affected by reflex pain typically suffer from headaches, spine, and extremity pain due to abnormal reflexes. Once this cycle of reflex pain begins, symptoms include unusual tightness, stiffness, pain, contractures of the affected muscle, and decreased functional abilities.

Causes Of Reflex Pain

The withdrawal reflex is a common reaction observed in almost all living species. The sole purpose of the withdrawal reflex is to protect the body from potential tissue damage. This involuntary reflex can occur in less than 0.5 seconds.  Withdrawal reflex can be elicited by both natural and artificial stimuli. Examples of natural stimuli include heat, punctures, muscle strains, and sprains. Artificial stimuli, such as electrical stimulation, is sometimes used to study how withdrawal reflex affects the body’s central pain process.

During reflex pain, the body’s muscles fail to relax, which is necessary to allow for range of motion. This continual contraction results in additional pain. It also causes imbalances that can lead to excitability in the muscles. This increases activity in the brain’s receptors that receive pain-signaling messages from the nervous system. The brain then responds by sending a message to the muscles that cause them to shorten and contract.

One recent investigation, published in the European Journal of Applied Physiology, revealed that the study of reflex withdrawal from electrical stimulation proved to be a useful tool in the objective assessment of certain chronic pain disorders. Other research has shown that abnormal withdrawal reflex can cause pain in a variety of manners. For example, when an injury occurs, the muscle tightens to compensate for the pain. To accomplish this process, opposing muscles, known as antagonists, contract. This, in turn, influences other muscle groups that can initiate a compensatory pattern of persistent reflex pain.

In another recent study, researchers used electric stimuli to investigate the association of abnormal withdrawal reflex and chronic pain. During this study, researchers applied electric stimuli to evoke reflexes in specific areas of the tibialis anterior muscles of 20 patients who complained of chronic pain and 25 pain-free subjects. The results of the study revealed that reflex thresholds after stimulation were significantly lower in the pain-free patients. This indicated that abnormal withdrawal reflex may play a significant role in patients experiencing chronic pain.

Treatments For Reflex Pain

Reflex PainBefore treating reflex pain, clinicians will conduct a comprehensive examination to identify potential dysfunctional areas of the body. During this manual examination, the physician relies on light palpitations to help identify which muscles are involved. The findings are then documented to help formulate a specific treatment plan. There is often a more painful area that can be located through palpitation that can be readily identified when the patient grimaces or when it tightens upon pressure. Although the palpitation is light, the patient’s response is often fairly pronounced. Once the painful area is identified, a physical therapy plan can be prescribed to help rebalance the body’s muscles and allow them to contract and relax normally.

During physical therapy, the therapist uses the concept of muscular reciprocal inhibition to activate and contract specific muscles. This allows the affected muscles to relax, while activating other muscles that may have previously been weakened. Restoring the body’s symmetry can also be accomplished through facilitation movements to the antagonist muscles.

The physical therapist may also employ TENS units. This device provides transcutaneous electrical nerve stimulation to affected body parts, helping to block pain signals. Patient education will also be provided to the patient concerning self-assessment techniques as well as instruction on how to treat painful areas. A routine exercise program may also be employed in order to complement the physical therapy.

There are several alternative methods for treating pain, including biofeedback and acupuncture. Biofeedback involves monitoring bodily functions such as breathing, blood pressure, and heart rate.  Patients are helped to understand how gaining control over these functions can help with managing their pain.


Reflex pain is a complex process that is frequently described as a frustrating sensation of prolonged pain that has been present in a specific area for a prolonged time. Reflexes are essential for the body to be able to protect itself; however, when injury interferes with their normal function, it is necessary to consult with a medical professional who can help identify the source and break the cycle of reflex pain.  Once abnormal reflexes are determined to be the cause of pain, a comprehensive physical therapy program can help restore body symmetry and facilitate pain-free function.


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