Quantitative Sensory Testing (QST): Difference between revisions

(Added initial content)
No edit summary
Line 9: Line 9:
</div>  
</div>  
== Introduction ==
== Introduction ==
Quantitative sensory testing (QST) is a systematic psychophysical test method used to measure sensory thresholds for pain, touch, vibration, and temperature sensations.<ref name=":0">Horowitz SH. Neuropathic pain: is the emperor wearing clothes. Current Therapy in Pain, WB Saunders. 2009:9-14.</ref>It quantifies individual sensory perceptions using direct patient feedback. Sophisticated computerised equipment is often used in clinical trials, but hand-held tools are also available for clinical use<ref name=":0" />.
Quantitative sensory testing (QST) is a systematic psychophysical test method used to measure sensory thresholds for pain, touch, vibration, and temperature sensations.<ref name=":0">Horowitz SH. Neuropathic pain: is the emperor wearing clothes. Current Therapy in Pain, WB Saunders. 2009:9-14.</ref>It quantifies individual sensory perceptions using direct patient feedback. It tests for sensory loss (hypoesthesia, hypoalgesia) and sensory gain (hyperesthesia, hyperalgesia, allodynia)<ref name=":2">Weaver KR, Griffioen MA, Klinedinst NJ, Galik E, Duarte AC, Colloca L, Resnick B, Dorsey SG, Renn CL. [[Quantitative sensory testing across chronic pain conditions and use in special populations.]] Frontiers in Pain Research. 2022 Jan 28;2:779068.</ref>. Sophisticated computerised equipment is often used in clinical trials, but hand-held tools are also available for clinical use<ref name=":0" />.


== Clinical Application ==
== Clinical Application ==
QST can be used to evaluate any condition that affects sensory function - it may help with diagnosis and disease monitoring. QST can be very useful to identify underlying pain mechanisms and pathophysiology, which can assist with targeted intervention strategies<ref name=":1">Mucke M, Cuhls H, Radbruch L, Baron R, Maier C, Tolle T, Treede RD, Rolke R. Quantitative sensory testing (QST). English version. Schmerz. 2016;35:153-60.</ref>. It is best to compare results with normative values, and it is best conducted early after onset of a condition. Conditions for which QST can be useful include<ref name=":1" />:
QST can be used to evaluate any condition that affects sensory function - it may help with diagnosis and disease monitoring. QST can be very useful to identify underlying contributing [[Pain Mechanisms|pain mechanisms]] and pathophysiology, which can assist with targeted intervention strategies<ref name=":2" /><ref name=":1">Mucke M, Cuhls H, Radbruch L, Baron R, Maier C, Tolle T, Treede RD, Rolke R. Quantitative sensory testing (QST). English version. Schmerz. 2016;35:153-60.</ref>. It is best to compare results with normative values, and it is best conducted early after onset of a condition.  


* Neuropathic pain
'''Conditions''' for which QST can be useful include<ref name=":2" /><ref name=":1" />:
* Polyneuropathy (diabetic, HIV-related, chemotherapy-related)
 
* [[Neuropathic Pain|Neuropathic pain]]
* [[Neuropathies|Polyneuropathy]] (diabetic, HIV-related, chemotherapy-related)
* Postherpetic neuralgia
* Postherpetic neuralgia
* Complex regional pain syndrome (CRPS)
* [[Complex Regional Pain Syndrome (CRPS)|Complex regional pain syndrome]] (CRPS)
* Chronic lower back pain
* [[Chronic Low Back Pain|Chronic low back pain]]
* [[Knee Osteoarthritis|Knee osteoarthritis]]


=== Procedure and Components ===
=== Procedure and Components ===
Line 30: Line 33:
=== Interpretation ===
=== Interpretation ===
{| class="wikitable"
{| class="wikitable"
|+Meaning of QST results<ref name=":0" />
|+Meaning of QST results<ref name=":0" /><ref name=":2" />
!'''Underlying mechanism'''
!'''Underlying mechanism'''
!'''QST finding'''
!'''QST finding'''
Line 41: Line 44:
|-
|-
|Peripheral sensitisation
|Peripheral sensitisation
|Heat hyperalgesia
|Heat hyperalgesia (lowered hot pain threshold)
|-
|-
|Central sensitisation
|Central sensitisation
|Static mechanical hyperalgesia or dynamic mechanical allodynia
|Static mechanical hyperalgesia or dynamic mechanical allodynia; temporal summation (repeated mechanical and thermal stimuli causes increased pain)
|-
|-
|Polyneuropathy
|Polyneuropathy
Line 62: Line 65:
'''2-point discrimination'''
'''2-point discrimination'''


== Evidence ==
'''Conditional pain modulation test (CPM)'''
 
CPM tests the function of central pain inhibition. Involves applying a noxious stimulus (thermal or mechanical) to a region remote from the painful site - if descending inhibitory control is functioning properly, the initial source of pain will be less intense during the application of the remote stimulus. <ref name=":2" />*****
 
== Specific Conditions ==
The table below summarises QST findings for specific conditions, as identified in research studies<ref name=":2" />:
{| class="wikitable"
|+
!'''Condition'''
!'''QST findings'''
|-
|''Low back pain''
|Decreased sensitivity (elevated threshold)
|-
|''Lower limb fractures''
|Decreased sensitivity (elevated threshold)
|-
|''Knee OA''
|Increased sensitivity (lowered thershold)
|}
 
== Summary ==
QST can be a very valubale clinical tool in patients with chronic pain by assisting to characterise pain experiences. It provides information about potential underlying mechanisms contributing to pain, therefore incorporating QST may improve the ability to implement individualised treatment plans based on underlying mechanisms<ref name=":2" />.


== Resources  ==
== Resources  ==
*'''[https://www.researchgate.net/publication/292339047_Quantitative_sensory_testing_QST_English_version#fullTextFileContent Quantitative Sensory Testing] -''' standardised full procedure
*'''[https://www.researchgate.net/profile/Walter-Magerl/publication/7084468_Quantitative_sensory_testing_in_the_German_Research_Network_on_Neuropathic_Pain_DFNS_Standardized_protocol_and_reference_values/links/5b3b86ed0f7e9b0df5e98620/Quantitative-sensory-testing-in-the-German-Research-Network-on-Neuropathic-Pain-DFNS-Standardized-protocol-and-reference-values.pdf Quantitative Sensory Testing] -''' standardised full procedure
*
*
or
or

Revision as of 17:18, 22 August 2023

This article or area is currently under construction and may only be partially complete. Please come back soon to see the finished work! (22/08/2023)

Original Editor - Melissa Coetsee

Top Contributors - Melissa Coetsee and Carina Therese Magtibay  

Introduction[edit | edit source]

Quantitative sensory testing (QST) is a systematic psychophysical test method used to measure sensory thresholds for pain, touch, vibration, and temperature sensations.[1]It quantifies individual sensory perceptions using direct patient feedback. It tests for sensory loss (hypoesthesia, hypoalgesia) and sensory gain (hyperesthesia, hyperalgesia, allodynia)[2]. Sophisticated computerised equipment is often used in clinical trials, but hand-held tools are also available for clinical use[1].

Clinical Application[edit | edit source]

QST can be used to evaluate any condition that affects sensory function - it may help with diagnosis and disease monitoring. QST can be very useful to identify underlying contributing pain mechanisms and pathophysiology, which can assist with targeted intervention strategies[2][3]. It is best to compare results with normative values, and it is best conducted early after onset of a condition.

Conditions for which QST can be useful include[2][3]:

Procedure and Components[edit | edit source]

To perform QST, a patient is stimulated with quantified sensory stimuli and based on patient feedback, perception thresholds are identified for the following sensory functions: light touch, pressure, vibration, thermal sensations, heat and cold pain. This way A-delta fibres (small diameter myelinated) and C-fibres (unmyelinated) are assessed.

  • Vibration
  • Cold
  • Heat

Interpretation[edit | edit source]

Meaning of QST results[1][2]
Underlying mechanism QST finding
Hypoesthesia (sensory loss) Elevated sensory thresholds
Allodynia and hyperalgesia Lowered sensory thresholds
Peripheral sensitisation Heat hyperalgesia (lowered hot pain threshold)
Central sensitisation Static mechanical hyperalgesia or dynamic mechanical allodynia; temporal summation (repeated mechanical and thermal stimuli causes increased pain)
Polyneuropathy All thresholds elevated
Small fibre neuropathy Vibration thresholds are normal, but others elevated

Limitations[edit | edit source]

  • QST abnormalities are present in non neuropathic pain, making it difficult to use QST as a definitive tool for identifying neuropathic pain[1]
  • Abnormal findings are not specific for peripheral nerve dysfunction, as central nervous system disorders will also alter sensory thresholds[1]
  • It is a subjective psychophysical test, entirely dependent on patient alertness, motivation and willingness to supply accurate feedback. There is large intra- and interindividual variation[1]

Complementary Tests[edit | edit source]

2-point discrimination

Conditional pain modulation test (CPM)

CPM tests the function of central pain inhibition. Involves applying a noxious stimulus (thermal or mechanical) to a region remote from the painful site - if descending inhibitory control is functioning properly, the initial source of pain will be less intense during the application of the remote stimulus. [2]*****

Specific Conditions[edit | edit source]

The table below summarises QST findings for specific conditions, as identified in research studies[2]:

Condition QST findings
Low back pain Decreased sensitivity (elevated threshold)
Lower limb fractures Decreased sensitivity (elevated threshold)
Knee OA Increased sensitivity (lowered thershold)

Summary[edit | edit source]

QST can be a very valubale clinical tool in patients with chronic pain by assisting to characterise pain experiences. It provides information about potential underlying mechanisms contributing to pain, therefore incorporating QST may improve the ability to implement individualised treatment plans based on underlying mechanisms[2].

Resources[edit | edit source]

or

  1. numbered list
  2. x

References[edit | edit source]

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Horowitz SH. Neuropathic pain: is the emperor wearing clothes. Current Therapy in Pain, WB Saunders. 2009:9-14.
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 Weaver KR, Griffioen MA, Klinedinst NJ, Galik E, Duarte AC, Colloca L, Resnick B, Dorsey SG, Renn CL. Quantitative sensory testing across chronic pain conditions and use in special populations. Frontiers in Pain Research. 2022 Jan 28;2:779068.
  3. 3.0 3.1 Mucke M, Cuhls H, Radbruch L, Baron R, Maier C, Tolle T, Treede RD, Rolke R. Quantitative sensory testing (QST). English version. Schmerz. 2016;35:153-60.