Test of Phalen

Abstract

The Test van Phalen, commonly known as Phalen’s Test, is a standardized clinical diagnostic maneuver primarily utilized for the assessment of potential compression of the median nerve, a key indicator of Carpal Tunnel Syndrome (CTS). The procedure requires the patient to maintain full passive wrist flexion, typically by pressing the dorsal surfaces of the hands together, for a duration of up to 60 seconds. The test is deemed positive if this position successfully reproduces or exacerbates characteristic sensory symptoms, such as paresthesias (tingling or numbness) in the distribution of the median nerve, occurring within the 60-second period.

Keywords

Phalen’s Test, Test van Phalen, Carpal Tunnel Syndrome, CTS, Median nerve, Sensory functions, Upper extremity, Neurological examination, Paresthesia, Flexion.

Authors

Phalen GS (1949)

Purpose

The primary purpose of the Test van Phalen is to serve as a rapid, non-invasive clinical screening tool for the diagnosis of Carpal Tunnel Syndrome (CTS). It is designed to mechanically increase pressure within the carpal tunnel by maximizing wrist flexion, thereby directly provoking the sensory symptoms associated with the compression of the median nerve.

This observational test falls under the category of physical examination maneuvers used to evaluate the functions of the peripheral nervous system, specifically targeting the upper extremity. Its utility lies in its ease of administration and immediate feedback regarding nerve irritability.

Construct

The underlying construct measured by Phalen’s Test is the mechanical sensitivity and degree of irritation of the median nerve as it traverses the confined space of the carpal tunnel. A positive result reflects the nerve’s immediate symptomatic response to externally applied mechanical stress induced by prolonged, forced wrist flexion.

The test is highly relevant to conditions categorized under Peripheral Nervous System disorders and Sensory functions and pain, as the onset of paresthesias or numbness confirms the compromise of sensory nerve fibers within the wrist structure.

Validity

The validity of Phalen’s Test is typically assessed in comparison to electrophysiological studies, such as nerve conduction velocity tests, which are often considered the gold standard for confirming CTS diagnosis. Clinical studies demonstrate that the test possesses variable sensitivity and specificity, depending on the population studied and the definition of a positive result.

It is generally regarded as a useful screening tool due to its high ease of use, though its specificity can be lower than desired, meaning that a positive Phalen’s Test must often be corroborated with a thorough patient history and other clinical findings to achieve a definitive diagnosis.

Reliability

The inter-rater reliability for Phalen’s Test is considered acceptable when the standardized procedure, specifically the required 60-second duration and maximal wrist flexion, is strictly adhered to by the clinician. Reliability is influenced by the patient’s ability to clearly and consistently report the onset and nature of the induced paresthesias and the consistent interpretation of these subjective symptoms by the examining clinician.

Factor Analysis

Phalen’s Test is a singular, direct observational clinical maneuver designed to elicit a specific physiological response (symptom provocation) related to a predefined anatomical structure (the carpal tunnel). As such, it is not a multi-item psychometric instrument, and traditional psychometric procedures like factor analysis are not applicable for determining underlying latent variables.

Instrument

Test Type: Observational Clinical Test

Format: Physical Examination Maneuver

Language Available: Generally language independent (physical test), but instructions are typically given in the local language.

Population Group: Adults, Elderly

Age Group: Adult (18+), Geriatric

Population Details: Individuals presenting with symptoms suggestive of Peripheral Nervous System disorders, particularly those affecting the upper extremity and sensory functions, such as tingling, numbness, or pain in the hand and wrist.

Test Methodology: The patient is asked to rest their elbows on a surface and then forcibly press the dorsal sides of their hands together, achieving maximal passive wrist flexion. This position must be held for up to one minute. The test is positive if symptoms of paresthesia occur within 60 seconds.

The original Explanation Form (Toelichtingsformulier) can be downloaded here: Toelichtingsformulier PDF

The original Instrument (Meetinstrument) document can be downloaded here: Meetinstrument PDF

Keywords

Clinical screening, Upper extremity, Sensory functions, CTS diagnosis, Neurological examination, Observation, Median nerve compression.

Authors

Author ORCID Identifier: Not Provided

Affiliation Email addresses: Not Provided

Correspondence Address: Not Provided

Permissions & Fee and Test Year

Test Year: 1949

Permissions and Fee: Phalen’s Test is a non-proprietary, widely accepted diagnostic technique published in academic literature. It is considered a fundamental component of standard neurological and orthopedic examination and is generally used without restriction or fee in clinical practice and research settings.

Reference’s

1. Phalen, G. S. (1949). The carpal-tunnel syndrome: Clinical evaluation of 500 cases. Clinical Orthopaedics and Related Research, 183, 11-21.
2. Phalen, G. S. (1951). Spontaneous compression of the median nerve at the wrist. Journal of the American Medical Association, 145(15), 1120-1122.

Items of the Test van Phalen

IMPORTANT: The following scale items must be preserved in their original language and must not be changed in any way.

Bij de test van Phalen wordt de patiënt gevraagd om gesteund met de ellebogen op de tafel beide handen in volledige flexie gedurende een minuut naar beneden te laten hangen. De vingers zijn hierbij in extensie. De test wordt als positief beschouwd, wanneer paresthesieën ontstaan binnen 60 seconden.1