Skip to main content
Select Source:

Reflex Tests

Reflex tests

Definition

Reflex tests are simple physical tests of nervous system function.

Purpose

A reflex is a simple nerve circuit. A stimulus, such as a light tap with a rubber hammer, causes sensory neurons (nerve cells) to send signals to the spinal cord. Here, the signals are conveyed both to the brain and to nerves that control muscles affected by the stimulus. Without any brain intervention, these muscles may respond to an appropriate stimulus by contracting. Newborn babies have a particular set of reflexes not present in older babies, children, and adults.

Reflex tests measure the presence and strength of a number of reflexes. In so doing, they help to assess the integrity of the nerve circuits involved. Reflex tests are performed as part of a neurological exam, either a mini-exam done to quickly confirm integrity of the spinal cord or a more complete exam performed to diagnose the presence and location of spinal cord injury or neuromuscular disease.

Deep tendon reflexes are responses to muscle stretch. The familiar knee-jerk reflex is an example; this reflex tests the integrity of the spinal cord in the lower back region. The usual set of deep tendon reflexes tested, involving increasingly higher regions of the spinal cord, are:

  • ankle
  • knee
  • abdomen
  • forearm
  • biceps
  • triceps

Another type of reflex test is called the Babinski test, which involves gently stroking the sole of the foot to assess proper development of the spine and cerebral cortex.

Description

The examiner places the person in a comfortable position, usually seated on the examination table with legs hanging free. The examiner uses a rubber mallet to strike different points on the individual's body and observes the response. The examiner may position, or hold, one of the limbs during testing, and may require exposure of the ankles, knees, abdomen, and arms. Reflexes can be difficult to elicit if the person is paying too much attention to the stimulus. To compensate for this, the person may be asked to perform some muscle contraction, such as clenching teeth or grasping and pulling the two hands apart. When performing the Babinski reflex test, the doctor will gently stroke the outer soles of the person's feet with the mallet while checking to see whether the big toe extends out as a result.

Risks

Reflex tests are entirely safe, and no special precautions are needed.

Normal results

The strength of the response depends partly on the strength of the stimulus. For this reason, the examiner will attempt to elicit the response with the smallest stimulus possible. Learning the range of normal responses requires some clinical training. Responses should be the same for both sides of the body. A normal response to the Babinski reflex test depends upon the age of the person being examined. In children under the age of one-and-a-half years, the big toe will extend out with or without the other toes. This is due to the fact that the fibers in the spinal cord and cerebral cortex have not been completely covered in myelin, the protein and lipid sheath that aids in processing neural signals. In adults and children over the age of one-and-a-half years, the myelin sheath should be completely formed, and, as a result, all the toes will curl under (planter flexion reflex).

Parental concerns

Parents should expect reflex tests to be included in every examination given to their children by a doctor or other healthcare provider. Reflex tests present no risks. Parents should only be concerned when they are told of abnormal reflex test results.

KEY TERMS

Babinski sign Dorsiflexion (curling) of the big toe on stimulating the sole of the foot.

Neuron The fundamental nerve cell of the nervous system.

See also Neonatal reflexes.

Resources

BOOKS

Bickley, Lynn S., and Peter G. Szilagyi. Bates' Guide to Physical Examination and History Taking, 6th ed. Philadelphia: Lippincott Williams & Wilkins, 2004.

Jarvis, Carolyn. Physical Examination and Health Assessment, 4th ed. Amsterdam, Netherlands: Elsevier, 2003.

LeBlond, Richard F., and Donald D. Brown. DeGowin's Diagnostic Examination, 8th ed. New York: McGraw-Hill, 2004.

Simel, David L. "Approach to the Patient: History and Physical Examination." In Cecil Textbook of Medicine, 22nd ed. Edited by Lee Goldman et al. Philadelphia: Saunders, 2003, pp. 1822.

PERIODICALS

Berilgen, M. S., et al. "Effects of epilepsy on autonomic nervous system and respiratory function tests." Epilepsy and Behavior 5, no. 4 (2004): 5136.

Calancie B., et al. "Tendon reflexes for predicting movement recovery after acute spinal cord injury in humans." Clinical Neurophysiology 115, no. 10 (2004): 235063.

Lefaucheur, J. P., and A. Creange. "Neurophysiological testing correlates with clinical examination according to fiber type involvement and severity in sensory neuropathy." Journal of Neurology, Neurosurgery, and Psychiatry 75, no. 3 (2004): 41722.

Mold, J. W., et al. "The prevalence, predictors, and consequences of peripheral sensory neuropathy in older patients." Journal of the American Board of Family Practice 17, no. 5 (2004): 30918.

Nadler, M. A., et al. "Cutaneomuscular reflexes following stroke: a 2-year longitudinal study." Journal of the Neurological Sciences 217, no. 2 (2004): 195203.

ORGANIZATIONS

American Academy of Family Physicians. 11400 Tomahawk Creek Parkway, Leawood, KS 662112672. Web site: <www.aafp.org/>.

American Academy of Neurology. 1080 Montreal Avenue, St. Paul, MN 55116. Web site: <www.aan.com/>.

American Academy of Pediatrics. 141 Northwest Point Blvd., Elk Grove Village, IL 600071098. Web site: <www.aap.org/default.htm>.

American Academy of Physical Medicine and Rehabilitation. One IBM Plaza, Suite 2500, Chicago, IL 606113604. Web site: <www.aapmr.org/>.

American College of Emergency Physicians. PO Box 619911, Dallas, TX 752619911. Web site: <www.acep.org/>.

American College of Physicians. 190 N Independence Mall West, Philadelphia, PA 191061572. Web site: <www.acponline.org/>.

American College of Sports Medicine. 401 W. Michigan St., Indianapolis, IN 462023233. Web site: <www.acsm.org/>.

International Brain Injury Association. 1150 South Washington St., Suite 210, Alexandria, VA 22314. Web site: <www.internationalbrain.org/>.

WEB SITES

"Moro reflex." MedlinePlus. Available online at <www.nlm.nih.gov/medlineplus/ency/article/003293.htm> (accessed December 22, 2004).

"Neuro-Ophthalmologic Disorders." The Merck Manual. Available online at <www.merck.com/mrkshared/mmanual/section14/chapter178/178b.jsp> (accessed December 22, 2004).

L. Fleming Fallon, Jr., MD, DrPH

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Reflex Tests." Gale Encyclopedia of Children's Health: Infancy through Adolescence. . Encyclopedia.com. 19 Dec. 2018 <https://www.encyclopedia.com>.

"Reflex Tests." Gale Encyclopedia of Children's Health: Infancy through Adolescence. . Encyclopedia.com. (December 19, 2018). https://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/reflex-tests

"Reflex Tests." Gale Encyclopedia of Children's Health: Infancy through Adolescence. . Retrieved December 19, 2018 from Encyclopedia.com: https://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/reflex-tests

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.

Reflex Tests

Reflex Tests

Definition

Reflex tests are simple physical tests of nervous system function.

Purpose

A reflex is a simple nerve circuit. A stimulus, such as a light tap with a rubber hammer, causes sensory neurons (nerve cells) to send signals to the spinal cord. Here, the signals are conveyed both to the brain and to nerves that control muscles affected by the stimulus. Without any brain intervention, these muscles may respond to an appropriate stimulus by contracting.

Reflex tests measure the presence and strength of a number of reflexes. In so doing, they help to assess the integrity of the nerve circuits involved. Reflex tests are performed as part of a neurological exam, either a "mini-exam" done to quickly confirm integrity of the spinal cord, or a more complete exam performed to diagnose the presence and location of spinal cord injury or neuromuscular disease.

Deep tendon reflexes are responses to muscle stretch. The familiar "knee-jerk" reflex is an example; this reflex tests the integrity of the spinal cord in the lower back region. The usual set of deep tendon reflexes tested, involving increasingly higher regions of the spinal cord, are:

  • ankle
  • knee
  • abdomen
  • forearm
  • biceps
  • triceps

Another type of reflex test is called the Babinski test, which involves gently stroking the sole of the foot to assess proper development of the spine and cerebral cortex.

Precautions

Reflex tests are entirely safe, and no special precautions are needed.

Description

The examiner positions the patient in a comfortable position, usually seated on the examination table with legs hanging free. The examiner uses a rubber mallet to strike different points on the patient's body, and observes the response. The examiner may position, or hold, one of the limbs during testing, and may require exposure of the ankles, knees, abdomen, and arms. Reflexes can be difficult to elicit if the patient is paying too much attention to the stimulus. To compensate for this, the patient may be asked to perform some muscle contraction, such as clenching teeth or grasping and pulling the two hands apart. When performing the Babinski reflex test, the doctor will gently stroke the outer soles of the patient's feet with the mallet while checking to see whether or not the big toe extends out as a result.

Normal results

The strength of the response depends partly on the strength of the stimulus. For this reason, the examiner will attempt to elicit the response with the smallest stimulus possible. Learning the range of normal responses requires some clinical training. Responses should be the same for both sides of the body. A normal response to the Babinski reflex test depends upon the age of the person being examined. In children under the age of one and a half years, the big toe will extend out with or without the other toes. This is due to the fact that the fibers in the spinal cord and cerebral cortex have not been completely covered in myelin, the protein and lipid sheath that aids in processing neural signals. In adults and children over the age of one and a half years, the myelin sheath should be completely formed, and, as a result, all the toes will curl under (planter flexion reflex).

Abnormal results

Weak or absent response may indicate damage to the nerves outside the spinal cord (peripheral neuropathy ), damage to the motor neurons just before or just after they leave the spinal cord (motor neuron disease), or muscle disease. Excessive response may indicate spinal cord damage above the level controlling the hyperactive response. Different responses on the two sides of the body may indicate early onset of progressive disease, or localized nerve damage, as from trauma. An adult or older child who responds to the Babinski with an extended big toe may have a lesion in the spinal cord or cerebral cortex.

Resources

OTHER

Rathe, Richard. "The Neurological Exam." A Healthy Me Page. July 2, 1997. http://www.ahealthyme.com.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Reflex Tests." Gale Encyclopedia of Medicine, 3rd ed.. . Encyclopedia.com. 19 Dec. 2018 <https://www.encyclopedia.com>.

"Reflex Tests." Gale Encyclopedia of Medicine, 3rd ed.. . Encyclopedia.com. (December 19, 2018). https://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/reflex-tests-0

"Reflex Tests." Gale Encyclopedia of Medicine, 3rd ed.. . Retrieved December 19, 2018 from Encyclopedia.com: https://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/reflex-tests-0

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.

Reflex Tests

Reflex Tests

Definition

Reflex tests are simple physical tests of nervous system function.

Purpose

A reflex is a simple nerve circuit. A stimulus, such as a light tap with a rubber hammer, causes sensory neurons (nerve cells) to send signals to the spinal cord. There, the signals are conveyed both to the brain and to nerves that control muscles affected by the stimulus. Without any brain intervention, these muscles may respond to an appropriate stimulus by contracting.

Reflex tests measure the presence and strength of a number of reflexes. In so doing, they help to assess the integrity of the nerve circuits involved. Reflex tests are performed as part of a neurological exam, either a "mini-exam" done to quickly confirm integrity of the spinal cord, or a more complete exam performed to diagnose the presence and location of a spinal cord injury or neuromuscular disease.

Deep tendon reflexes are responses to muscle stretch. The familiar "knee-jerk" reflex is an example of a reflex. This tests the integrity of the spinal cord in the lower back region. The usual set of deep tendon reflexes tested, involving increasingly higher regions of the spinal cord, includes:

  • ankle
  • knee
  • abdomen
  • forearm
  • biceps
  • triceps
  • patellar

Another type of reflex test is called the Babinski test, which involves gently stroking the sole of the foot to assess proper development and function of the spine and cerebral cortex.

Precautions

Reflex tests are entirely safe, and no special precautions are needed.

Description

The examiner uses a reflex hammer or rubber mallet to strike different points on the examinee's body, and observes the response. The points chosen for eliciting reflexes are the tendons of specific muscles. Tapping specific sites is intended to provide a quick stretch to the muscle. Muscle spindles, or receptors, mediate the reflex lying within the muscle—not the site of the hammer strike. The examiner may position, or hold, one of the limbs during testing, and may require exposure of the ankles, knees, abdomen, and arms. Reflexes can be difficult to elicit if the individual being examined is paying too much attention to the stimulus. To compensate for this, that person may be asked to perform some muscle contraction, such as clenching teeth or grasping and pulling the two hands apart. When performing the Babinski reflex test, the examiner will gently stroke the outer soles of the person's feet with the mallet while checking to see whether or not the big toe extends out as a result.

Muscle stretch (deep tendon) reflexes
Reflex Stimulus Response
Source: Rothstein, J.M., S.H. Roy, and S.L. Wolf. The Rehabilitation Specialist's Handbook. 2nd ed. Philadelphia: F.A. Davis Co., 1998.
BicepsTap biceps tendonContraction of biceps
Brachioradialis (periosteradial)Tap styoid process of radius (insertion of brachioradialis)Flexion of elbow and pronation of forearm
Jaw (maxillary)Tap mandible in half-open positionClosure of jaw
PatellarTap patellar tendonExtension of leg at knee
TendocalcaneusTap Achilles tendonPlantar flexion at ankle
TricepsTap triceps tendonExtension of elbow
Wrist extensionTap wrist extensor tendonsExtension of wrist
Wrist flexionTap wrist flexor tendonFlexion of wrist

Preparation

The examiner positions the person to be examined in a comfortable position, usually seated on the examination table with legs hanging free. There is no other preparation.

Aftercare

A reflex examination is not invasive. No care after the examination is required.

Complications

The pressure exerted by a reflex hammer is minimal and does not hurt the person being examined. A reflex examination is not invasive. There are no complications from performing the examination.

Results

Normal results

The strength of the response depends partly on the strength of the stimulus. For this reason, an examiner will attempt to elicit the response with the smallest stimulus possible. Learning the range of normal responses requires some clinical training. Responses should be the same on both sides of the body. A normal response to the Babinski reflex test depends upon the age of the person being examined. In children under the age of one and a half years, the big toe will extend out with or without the other toes. This is due to the fact that the fibers in the spinal cord and cerebral cortex have not been completely covered in myelin, the protein and lipid sheath that aids in processing neural signals. In adults and children over the age of one and a half years, the myelin sheath should be completely formed and as a result, all the toes will curl under (plantar flexion reflex).

KEY TERMS

Lesion— A pathologic change in body tissue.

Myelin— A substance composed largely of fat that constitutes the sheaths of various nerve fibers throughout the body.

Neurology— The study of nerves.

Abnormal results

Weak or absent response may indicate damage to the nerves outside the spinal cord (peripheral neuropathy), damage to the motor neurons just before or just after they leave the spinal cord (motor neuron disease), or muscle disease. Excessive response may indicate spinal cord damage above the level controlling the hyperactive response. Different responses on the two sides of the body may indicate early onset of progressive disease, or localized nerve damage, as from trauma. An adult or older child who responds to the Babinski with an extended big toe may have a lesion in the spinal cord or cerebral cortex.

Health care team roles

A reflex examination is usually conducted by a physician. Neurologists (doctors with specialized training in neurology) often perform reflex tests. Physician assistants, physical therapists, and nurses may also test reflexes as they examine or evaluate individuals.

Resources

BOOKS

Adams, Raymond D., Maurice Victor, and Allen H. Ropper. Adam's & Victor's Principles of Neurology, 6th ed. New York: McGraw Hill, 1997.

Aminoff, Michael J. Neurology and General Medicine, 3rd ed. London: Churchill Livingstone, 2001.

Bickley, Lynn S., Robert A. Hoekelman, and Barbara Bates. Bates' Guide to Physical Examination and History Taking. Philadelphia, PA: Lippincott, 1999.

DeGowin, Robert L., and Donald D. DeGowin. DeGowin's Diagnostic Examination, 7th ed. New York: McGraw Hill, 1999.

Seidel, Henry M. Mosby's Guide to Physical Examination, 4th ed. St. Louis, MO: Mosby Year Book, 1999.

Shwartz, Mark A., and William Schmitt. Textbook of Physical Diagnosis: History and Examination, 3rd ed. Philadelphia, PA: Saunders, 1998.

ORGANIZATIONS

American Academy of Family Physicians. 11400 Tomahawk Creek Parkway, Leawood, KS 66211-2672. (913) 906-6000. 〈http://www.aafp.org/〉. [email protected]

American Academy of Neurology. 1080 Montreal Avenue, St. Paul, Minnesota 55116. (651) 695-1940. 〈http://www.aan.com/resources.html〉. [email protected]

American College of Physicians. 190 N Independence Mall West, Philadelphia, PA 19106-1572. (800) 523-1546 x2600 or (215) 351-2600. 〈http://www.acponline.org/cgi-bin/feedback〉.

OTHER

Explore Science. 〈http://www.explorescience.com/activities/Activity_page.cfm?ActivityID=38〉.

King's College (London). 〈http://www.umds.ac.uk/physiology/mcal/sreflex.html〉.

Loyola University (Chicago). 〈http://www.meddean.luc.edu/lumen/MedEd/medicine/pulmonar/pd/pstep56.htm〉.

University of Washington. 〈http://faculty.washington.edu/chudler/chreflex.html〉.

Washington University (St. Louis). 〈http://www.neuro.wustl.edu/neuromuscular/mother/reflex.html〉.

Cite this article
Pick a style below, and copy the text for your bibliography.

  • MLA
  • Chicago
  • APA

"Reflex Tests." Gale Encyclopedia of Nursing and Allied Health. . Encyclopedia.com. 19 Dec. 2018 <https://www.encyclopedia.com>.

"Reflex Tests." Gale Encyclopedia of Nursing and Allied Health. . Encyclopedia.com. (December 19, 2018). https://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/reflex-tests-1

"Reflex Tests." Gale Encyclopedia of Nursing and Allied Health. . Retrieved December 19, 2018 from Encyclopedia.com: https://www.encyclopedia.com/medicine/encyclopedias-almanacs-transcripts-and-maps/reflex-tests-1

Learn more about citation styles

Citation styles

Encyclopedia.com gives you the ability to cite reference entries and articles according to common styles from the Modern Language Association (MLA), The Chicago Manual of Style, and the American Psychological Association (APA).

Within the “Cite this article” tool, pick a style to see how all available information looks when formatted according to that style. Then, copy and paste the text into your bibliography or works cited list.

Because each style has its own formatting nuances that evolve over time and not all information is available for every reference entry or article, Encyclopedia.com cannot guarantee each citation it generates. Therefore, it’s best to use Encyclopedia.com citations as a starting point before checking the style against your school or publication’s requirements and the most-recent information available at these sites:

Modern Language Association

http://www.mla.org/style

The Chicago Manual of Style

http://www.chicagomanualofstyle.org/tools_citationguide.html

American Psychological Association

http://apastyle.apa.org/

Notes:
  • Most online reference entries and articles do not have page numbers. Therefore, that information is unavailable for most Encyclopedia.com content. However, the date of retrieval is often important. Refer to each style’s convention regarding the best way to format page numbers and retrieval dates.
  • In addition to the MLA, Chicago, and APA styles, your school, university, publication, or institution may have its own requirements for citations. Therefore, be sure to refer to those guidelines when editing your bibliography or works cited list.