About all

Dermatome chart leg: Dermatomes – Physiopedia

by alexxlab

Dermatomes – Physiopedia

Original Editor – Lucinda Hampton

Top Contributors –

Naomi O’Reilly,

Anas Mohamed,

Lucinda hampton,

Joao Costa,

Nikhil Benhur Abburi,

Rachael Lowe,

Kim Jackson and

Blessed Denzel Vhudzijena




Lead Editors  

Contents

  • 1 Dermatomes
  • 2 History
  • 3 Purpose
  • 4 Technique
  • 5 Controversies
  • 6 Clinical Significance
  • 7 References

The term “dermatome” is a combination of two Greek words; “derma” meaning “skin”, and “tome”, meaning “cutting” or “thin segment”. Dermatomes are areas of the skin whose sensory distribution is innervated by the afferent nerve fibres from the dorsal root of a specific single spinal nerve root, which is that portion of a peripheral nerve that “connects” the nerve to the spinal cord.

Nerve roots arise from each level of the spinal cord (e. g., C3, C4), and many, but not all, intermingle in a plexus (brachial, lumbar, or lumbosacral) to form different peripheral nerves as discussed above. This arrangement can result in a single nerve root supplying more than one peripheral nerve. For example, the median nerve is derived from the C6, C7, C8, and T1 Nerve Roots, whereas the ulnar nerve is derived from C7, C8, and T1.

In total there are 30 dermatomes that relay sensation from a particular region of the skin to the brain – 8 cervical nerves (note C1 has no corresponding dermatomal area), 12 thoracic nerves, 5 lumbar nerves and 5 sacral nerves. Each of these spinal nerves roots.[1] Dysfunction or damage to a spinal nerve root from infection, compression, or traumatic injury can trigger symptoms in the corresponding dermatome. [2]

[3]

Table. 1 Dermatomes
Nerve RootDermatome
CervicalC2Supply Skin of NeckTemple, Forehead, Occiput
C3Entire Neck, Posterior Cheek, Temporal Area, Prolongation forward under Mandible
C4Shoulder Area, Clavicular Area, Upper Scapular Area
C5Supply the Arms Deltoid Area, Anterior aspect of entire arm to base of thumb
C6Anterior Arm, Radial side of hand to thumb and index finger
C7Lateral Arm and Forearm to index, long, and ring fingers
C8Medial Arm and forearm to long, ring, and little fingers
ThoracicT1Medial side of forearm to base of little finger
T2Supply the chest and abdomenMedial side of upper arm to medial elbow, pectoral and midscapular areas
T3 – 6Upper Thorax
T5 – 7Costal Margin
T8 – 12Abdomen and Lumbar Region
LumbarL1Back, over trochanter and groin
L2Back, front of thigh to knee
L3Supply Skin of LegsBack, upper buttock, anterior thigh and knee, medial lower leg
L4Medial buttock, latera thigh, medial leg, dorsum of foot, big toe
L5Buttock, posterior and lateral thigh, lateral aspect of leg, dorsum of foot, medial half of sole, first, second, and third toes
SacralS1Buttock, Thigh, and Leg Posterior
S2Supply GroinSame as S1
S3Groin, medial thigh to knee
S4Perineum, genitals, lower sacrum
CoccygealThe dermatome corresponding with the coccygeal nerves is located on the buttocks, in the area directly around the coccyx. [4][5]

The idea of dermatomes originated from initial efforts to associate anatomy with the physiology of sensation. Multiple definitions of dermatomes exist, and several maps are commonly employed. Although they are valuable, dermatomes vary significantly between maps and even among individuals,[6] with some evidence suggesting that current dermatome maps are inaccurate and based on flawed studies.[7][8]

The medical profession typically recognised two primary maps of dermatomes. Firstly, the Keegan and Garret Map (Fig.1) from 1948, which illustrates dermatomes in alignment with the developmental progression of the limb segments. Secondly, the Foerster Map from 1933, which portrays the medial area of the upper limb as being innervated by T1-T3, depicting the pain distribution from angina or myocardial infarction. This latter map is the most frequently used in healthcare and accounts for the dermatomes used in the American Spinal Cord Injury Association Impairment Scale (ASIA Scale). In recent years there have been few attempts at verifying these original dermatome maps. Lee et al conducted an in-depth review that examined the discrepancies among dermatome maps. They put forth an “evidence-based” dermatome map that combined elements of previous maps (Fig.3). Though the application of the term “evidence-based” may be somewhat questionable, their proposed map represents a systematic attempt to synthesise the most credible evidence available.[6][7]

Testing of dermatomes is part of the neurological examination. They are primarily used to determine whether the sensory loss on a limb corresponds to a single spinal segment, implying the lesion is of that nerve root (i.e., radiculopathy), and to assign the neurologic “level” to a spinal cord lesion[9].

Dermatome Testing is done ideally with a pin and cotton wool. Ask the patient to close their eyes and give the therapist feedback regarding the various stimuli. Testing should be done on specific dermatomes and should be compared to bilaterally.

  • Light Touch Test – Light Touch Sensation – Dab a piece of cotton wool on an area of skin [10]
  • Pinprick Test – Pain Sensation – Gently touches the skin with the pin ask the patient whether it feels sharp or blunt

During the review of systems, asking the patient to carefully describe the pattern or distribution of sensory symptoms (e.g., tingling, numbness, diminished, or absent sensation) provides the therapist with preliminary information to help guide the examination and to assist in identifying the dermatome(s) and nerve(s) involved.[11]

Light touch dermatomes are larger than pain dermatomes. When only one or two segments are affected, testing for pain sensibility is a more sensitive method of examination than testing for light touch.[9]

Dermatomes have a segmented distribution throughout your body. The exact dermatome pattern can actually vary from person to person. Some overlap between neighboring dermatomes may also occur. There exist some discrepancies among published dermatome maps based on the methodologies used to identify skin segment innervation.

In a clinical commentary, Downs and Laporte discuss the history of dermatome mapping, including the variations in methodologies employed, and the inconsistencies in the dermatome maps used in education and practice.[11] [[Laporte C. Conflicting dermatome maps: educational and clinical implications. journal of orthopaedic & sports physical therapy. 2011 Jun;41(6):42[12]7-34.]]

Dermatomes are important because they can help to assess and diagnose a variety of conditions. Neurological screening of dermatomes helps to assess patterns of sensory loss that can suggest specific spinal nerve involvement. For instance, symptoms that occur along a specific dermatome may indicate disruption or damage to a specific nerve root in the spine.

  • Nerve Entrapment
  • Radiculopathy
  • Spinal Cord Injury
  • Herpes Zoster [2]
  1. ↑ Wikipedia Dermatome. Available from: https://en.wikipedia.org/wiki/Dermatome_(anatomy) (last accessed 23.4.2019)
  2. ↑ 2.02.1 Medical news today What and where are dermatomes? Available:https://www.medicalnewstoday.com/articles/what-are-dermatomes (accessed 25.5.2022)
  3. ↑ M Roehrs. Dermatomes. Available from: https://www.youtube.com/watch?v=CYZBH6NX8wg&feature=youtu.be (last accessed 23.4.2019)
  4. ↑ Medical news today What and where are dermatomes? Available:https://www.medicalnewstoday.com/articles/what-are-dermatomes (accessed 25.5.2022)
  5. ↑ David J. Magee. Orthopedic Physical Assessment. 6th edition. Elsevier. 2014.
  6. ↑ 6.06.1 Apok V, Gurusinghe NT, Mitchell JD, Emsley HC. Dermatomes and dogma. Practical neurology. 2011 Apr 1;11(2):100-5.
  7. ↑ 7.07. 1 Lee MW, McPhee RW, Stringer MD. An evidence-based approach to human dermatomes. Australasian Musculoskeletal Medicine. 2013 Jun;18(1):14-22.
  8. ↑ Downs MB, Laporte C. Conflicting dermatome maps: educational and clinical implications. journal of orthopaedic & sports physical therapy. 2011 Jun;41(6):427-34.
  9. ↑ 9.09.1 Liebenson C, editor. Rehabilitation of the spine: a practitioner’s manual. Lippincott Williams & Wilkins; 2007.Available: https://www.sciencedirect.com/topics/medicine-and-dentistry/dermatome (accessed 25.5.2022)
  10. ↑ Slide share. Dermatomes and myotomes. Available from: https://www.slideshare.net/TafzzSailo/special-test-for-dermatomes-and-myotomes (last accessed 23.4.2019)
  11. ↑ 11.011.1 Susan B.O’Sullivan, Thomas J. Schmitz, George D. Fulk. Physical Rehabilitation. 6th edition. F. A. Davis Company. 2014.
  12. ↑ Downs MB, Laporte C. Conflicting dermatome maps: educational and clinical implications. journal of orthopaedic & sports physical therapy. 2011 Jun;41(6):427-34.

Dermatomes – Physiopedia

Original Editor – Lucinda Hampton

Top Contributors –

Naomi O’Reilly,

Anas Mohamed,

Lucinda hampton,

Joao Costa,

Nikhil Benhur Abburi,

Rachael Lowe,

Kim Jackson and

Blessed Denzel Vhudzijena




Lead Editors  

Contents

  • 1 Dermatomes
  • 2 History
  • 3 Purpose
  • 4 Technique
  • 5 Controversies
  • 6 Clinical Significance
  • 7 References

The term “dermatome” is a combination of two Greek words; “derma” meaning “skin”, and “tome”, meaning “cutting” or “thin segment”. Dermatomes are areas of the skin whose sensory distribution is innervated by the afferent nerve fibres from the dorsal root of a specific single spinal nerve root, which is that portion of a peripheral nerve that “connects” the nerve to the spinal cord.

Nerve roots arise from each level of the spinal cord (e.g., C3, C4), and many, but not all, intermingle in a plexus (brachial, lumbar, or lumbosacral) to form different peripheral nerves as discussed above. This arrangement can result in a single nerve root supplying more than one peripheral nerve. For example, the median nerve is derived from the C6, C7, C8, and T1 Nerve Roots, whereas the ulnar nerve is derived from C7, C8, and T1.

In total there are 30 dermatomes that relay sensation from a particular region of the skin to the brain – 8 cervical nerves (note C1 has no corresponding dermatomal area), 12 thoracic nerves, 5 lumbar nerves and 5 sacral nerves. Each of these spinal nerves roots.[1] Dysfunction or damage to a spinal nerve root from infection, compression, or traumatic injury can trigger symptoms in the corresponding dermatome. [2]

[3]

Table. 1 Dermatomes
Nerve RootDermatome
CervicalC2Supply Skin of NeckTemple, Forehead, Occiput
C3Entire Neck, Posterior Cheek, Temporal Area, Prolongation forward under Mandible
C4Shoulder Area, Clavicular Area, Upper Scapular Area
C5Supply the Arms Deltoid Area, Anterior aspect of entire arm to base of thumb
C6Anterior Arm, Radial side of hand to thumb and index finger
C7Lateral Arm and Forearm to index, long, and ring fingers
C8Medial Arm and forearm to long, ring, and little fingers
ThoracicT1Medial side of forearm to base of little finger
T2Supply the chest and abdomenMedial side of upper arm to medial elbow, pectoral and midscapular areas
T3 – 6Upper Thorax
T5 – 7Costal Margin
T8 – 12Abdomen and Lumbar Region
LumbarL1Back, over trochanter and groin
L2Back, front of thigh to knee
L3Supply Skin of LegsBack, upper buttock, anterior thigh and knee, medial lower leg
L4Medial buttock, latera thigh, medial leg, dorsum of foot, big toe
L5Buttock, posterior and lateral thigh, lateral aspect of leg, dorsum of foot, medial half of sole, first, second, and third toes
SacralS1Buttock, Thigh, and Leg Posterior
S2Supply GroinSame as S1
S3Groin, medial thigh to knee
S4Perineum, genitals, lower sacrum
CoccygealThe dermatome corresponding with the coccygeal nerves is located on the buttocks, in the area directly around the coccyx. [4][5]

The idea of dermatomes originated from initial efforts to associate anatomy with the physiology of sensation. Multiple definitions of dermatomes exist, and several maps are commonly employed. Although they are valuable, dermatomes vary significantly between maps and even among individuals,[6] with some evidence suggesting that current dermatome maps are inaccurate and based on flawed studies.[7][8]

The medical profession typically recognised two primary maps of dermatomes. Firstly, the Keegan and Garret Map (Fig.1) from 1948, which illustrates dermatomes in alignment with the developmental progression of the limb segments. Secondly, the Foerster Map from 1933, which portrays the medial area of the upper limb as being innervated by T1-T3, depicting the pain distribution from angina or myocardial infarction. This latter map is the most frequently used in healthcare and accounts for the dermatomes used in the American Spinal Cord Injury Association Impairment Scale (ASIA Scale). In recent years there have been few attempts at verifying these original dermatome maps. Lee et al conducted an in-depth review that examined the discrepancies among dermatome maps. They put forth an “evidence-based” dermatome map that combined elements of previous maps (Fig.3). Though the application of the term “evidence-based” may be somewhat questionable, their proposed map represents a systematic attempt to synthesise the most credible evidence available.[6][7]

Testing of dermatomes is part of the neurological examination. They are primarily used to determine whether the sensory loss on a limb corresponds to a single spinal segment, implying the lesion is of that nerve root (i.e., radiculopathy), and to assign the neurologic “level” to a spinal cord lesion[9].

Dermatome Testing is done ideally with a pin and cotton wool. Ask the patient to close their eyes and give the therapist feedback regarding the various stimuli. Testing should be done on specific dermatomes and should be compared to bilaterally.

  • Light Touch Test – Light Touch Sensation – Dab a piece of cotton wool on an area of skin [10]
  • Pinprick Test – Pain Sensation – Gently touches the skin with the pin ask the patient whether it feels sharp or blunt

During the review of systems, asking the patient to carefully describe the pattern or distribution of sensory symptoms (e.g., tingling, numbness, diminished, or absent sensation) provides the therapist with preliminary information to help guide the examination and to assist in identifying the dermatome(s) and nerve(s) involved.[11]

Light touch dermatomes are larger than pain dermatomes. When only one or two segments are affected, testing for pain sensibility is a more sensitive method of examination than testing for light touch.[9]

Dermatomes have a segmented distribution throughout your body. The exact dermatome pattern can actually vary from person to person. Some overlap between neighboring dermatomes may also occur. There exist some discrepancies among published dermatome maps based on the methodologies used to identify skin segment innervation.

In a clinical commentary, Downs and Laporte discuss the history of dermatome mapping, including the variations in methodologies employed, and the inconsistencies in the dermatome maps used in education and practice.[11] [[Laporte C. Conflicting dermatome maps: educational and clinical implications. journal of orthopaedic & sports physical therapy. 2011 Jun;41(6):42[12]7-34.]]

Dermatomes are important because they can help to assess and diagnose a variety of conditions. Neurological screening of dermatomes helps to assess patterns of sensory loss that can suggest specific spinal nerve involvement. For instance, symptoms that occur along a specific dermatome may indicate disruption or damage to a specific nerve root in the spine.

  • Nerve Entrapment
  • Radiculopathy
  • Spinal Cord Injury
  • Herpes Zoster [2]
  1. ↑ Wikipedia Dermatome. Available from: https://en.wikipedia.org/wiki/Dermatome_(anatomy) (last accessed 23.4.2019)
  2. ↑ 2.02.1 Medical news today What and where are dermatomes? Available:https://www.medicalnewstoday.com/articles/what-are-dermatomes (accessed 25.5.2022)
  3. ↑ M Roehrs. Dermatomes. Available from: https://www.youtube.com/watch?v=CYZBH6NX8wg&feature=youtu.be (last accessed 23.4.2019)
  4. ↑ Medical news today What and where are dermatomes? Available:https://www.medicalnewstoday.com/articles/what-are-dermatomes (accessed 25.5.2022)
  5. ↑ David J. Magee. Orthopedic Physical Assessment. 6th edition. Elsevier. 2014.
  6. ↑ 6.06.1 Apok V, Gurusinghe NT, Mitchell JD, Emsley HC. Dermatomes and dogma. Practical neurology. 2011 Apr 1;11(2):100-5.
  7. ↑ 7.07. 1 Lee MW, McPhee RW, Stringer MD. An evidence-based approach to human dermatomes. Australasian Musculoskeletal Medicine. 2013 Jun;18(1):14-22.
  8. ↑ Downs MB, Laporte C. Conflicting dermatome maps: educational and clinical implications. journal of orthopaedic & sports physical therapy. 2011 Jun;41(6):427-34.
  9. ↑ 9.09.1 Liebenson C, editor. Rehabilitation of the spine: a practitioner’s manual. Lippincott Williams & Wilkins; 2007.Available: https://www.sciencedirect.com/topics/medicine-and-dentistry/dermatome (accessed 25.5.2022)
  10. ↑ Slide share. Dermatomes and myotomes. Available from: https://www.slideshare.net/TafzzSailo/special-test-for-dermatomes-and-myotomes (last accessed 23.4.2019)
  11. ↑ 11.011.1 Susan B.O’Sullivan, Thomas J. Schmitz, George D. Fulk. Physical Rehabilitation. 6th edition. F. A. Davis Company. 2014.
  12. ↑ Downs MB, Laporte C. Conflicting dermatome maps: educational and clinical implications. journal of orthopaedic & sports physical therapy. 2011 Jun;41(6):427-34.

Hip Anatomy Shoulder dermatome, Abdomen, swimwear, anatomy, anatomy png

  • swimwear,
  • anatomy,
  • hand,
  • belly,
  • underwear,
  • active underwear,
  • limb,
  • muscles,
  • neck,
  • anterior thigh,
  • basin,
  • shoulder,
  • sleeve,
  • thigh,
  • chest,
  • chest,
  • swimsuit,
  • clothing,
  • coronal plane,
  • drumstick,
  • cutaneous nerve,
  • dermatome,
  • human leg,
  • back,
  • elbow,
  • joint,
  • png,
  • transparent,
  • free download

    • About this PNG

    Image size

    600x600px

    File size

    260.65KB

    MIME type

    Image/png

    Download PNG ( 260.65KB )

    resize PNG

    width(px)

    height(px)

    License

    Non-Commercial Use, DMCA Contact Us

      org/ImageGallery” align=”middle”>

    • human physiology, Human anatomy Muscle Human body Muscular system, muscles, miscellaneous, human, muscle png
      1000x1000px
      267.79KB

    • human anatomy diagram, Spinal cord dermatome Peripheral nervous system Spinal nerve Myotome anatomy, miscellaneous, angle, anatomy png
      700x690px
      435.06KB

    • Active Underwear Waist Shoulder Cosmetic treatment, arm, abdomen, active Underwear png
      667x1000px
      1.47MB

    • Arm cryolipolysis Human arm Thigh skin, arm, physical Fitness, people, weight Loss png
      600x2415px
      1.1MB

    • Human body Shoulder Hip Family medicine Clinic Organ, blood pressure, miscellaneous, purple, arm png
      1000x2304px
      1. 61MB

    • skeleton illustration, Human skeleton Human body Anatomy, bones, miscellaneous, bones, human png
      615x1600px
      688.33KB

    • Vladimir Active Undergarment Physical fitness Health Energy, fit girl, hand, fitness Professional, arm png
      419x740px
      223.54KB

    • Yoga Body Health Flexibility Aromatherapy, yoga world, physical Fitness, sport, arm png
      1098x1000px
      1.18MB

    • Back pain Shoulder pain Neck joint Muscle, back pain, miscellaneous, tshirt, arm png
      600x568px
      188.69KB

    • human leg muscles illustration, Ankle Muscle Anatomy, miscellaneous, hand, foot png
      1434x1484px
      2. 22MB

    • Human body Human leg Organ Homo sapiens Limb, sculpting, hand, people, monochrome png
      914x802px
      19.13KB

    • HUMAN ANATOMY Human anatomy Muscular system Homo sapiens, others, physical Fitness, human, anatomy png
      512x512px
      109.71KB

    • human body anatomy, Skeletal muscle Human skeleton Muscular system, Human muscle anatomy movement, people, human, anatomy png
      1100x1003px
      690.02KB

    • Finger Arm Human body Homo sapiens, hand, hand, people, wrist png
      400x1549px
      384.03KB

    • person touching both legs, Laser hair removal Waxing Epilation, hair, physical Fitness, hand, cosmetics png
      513x690px
      210. 86KB

    • woman’s back pain illustration, Low back pain Neck pain, physical Fitness, pain, pain png
      1140x1706px
      395.36KB

    • Hand, Hands, two-handed gesture, hand, wrist, forelimb png
      1588x1788px
      1.57MB

    • Laser hair removal Skin Depilason, depilation, physical Fitness, hand, cosmetology png
      518x665px
      195.15KB

    • Human body Organ Human anatomy Human back, structure of human organs, hand, human, anatomy png
      1147x1378px
      1.92MB

    • Zaira Nara Model Argentina Clothing, model, celebrities, blue, fashion png
      625x1176px
      803.56KB

    • org/ImageObject”>

      Warne’s Fitness Fitness Center Fitness Center Personal trainer, others, miscellaneous, fitness, arm png
      371x750px
      276.78KB

    • Organ Human body Homo sapiens Human digestive system Muscle, organ, superhero, hand, people png
      2000x5499px
      2.18MB

    • man with muscle illustration, Muscular system Skeletal muscle Human body Human skeleton, human body, miscellaneous, physical Health, human Body png
      3000x2953px
      3.8MB

    • Weight loss Exercise Diet Weight management Weight gain, Fitness Banner, physical Fitness, hand, weight Loss png
      500x571px
      236.97KB

    • woman holding pair of dumbbells, Dietary supplement Bodybuilding Bodybuilding Physical exercise Fitness, weight loss, fitness Professional, sport png
      500x800px
      552. 62KB

    • Human body Organ Homo sapiens Anatomy Human skin, body, miscellaneous, hand, human png
      3000x6675px
      601.21KB

    • Hip Hime cut Human leg Black hair, hair, cg Artwork, black Hair, hand png
      420x1600px
      311.79KB

    • Shoulder Arm Human leg Thigh, plank, physical Fitness, people, abdomen png
      913x608px
      40.28KB

    • Homo sapiens Human body Human anatomy Biology, human body, miscellaneous, human, biology png
      1062x2344px
      3.19MB

    • human muscular system illustration, Human body Muscular anatomy Muscular system Organ, Human body, physical Fitness, people, human png
      1100x810px
      522. 57KB

    • Health Weight loss Dieta do Metabolismo Rápido Abdominal obesity, health, physical Fitness, swimsuit Top, nutrition png
      900x910px
      598.37KB

    • Bodyweight training Physical fitness Fitness Center Weight loss, others, physical Fitness, weight Loss, fitness png
      488x1342px
      520.34KB

    • Hip Fat Abdominal obesity Adipose tissue, arm, people, human, swimwear png
      864x576px
      309.72KB

    • Deep vein thrombosis Human leg Hip Thrombus, legs, people, ankle, symptom png
      839x800px
      300.33KB

    • woman holding pair of dumbbells, Forever Living Products Weight loss Detoxification Aloe vera Weight management, 60s, miscellaneous, physical Fitness, food png
      2627x4735px
      5. 45MB

    • woman stretching, Yoga Pilates Physical exercise Asento Physical fitness, yoga mat, hand, sports, wrist png
      900x522px
      244.82KB

    • woman using headphones, Fitness training boot camp Physical fitness, Summer playlist, miscellaneous, sport, boxing Glove png
      536x789px
      110.25KB

    • woman wearing tank top and drawstring shorts, Chrome Weight Loss Diet Slimming Slim 10, slim body, miscellaneous, white, physical Fitness png
      640x1040px
      377.43KB

    • Thumb Homo sapiens Human body Anatomy Drawing, humano, white, face, text png
      1000x1414px
      43.34KB

    • Push-up strength training Exercise Plank Triceps shoulder muscle, others, physical Fitness, arm, arm png
      890x585px
      368. 2KB

    • Human leg Arm Limb Human body Joint, results, hand, people, wrist png
      2019x1488px
      1.06MB

    • woman exercising while holding two dumbbells, Physical fitness Fitness center Personal trainer, Weight Loss, fitness Professional, arm png
      1257x843px
      647.61KB

    • human anatomy, Myofascial trigger point Massage Physical therapy Muscle, anatomy, miscellaneous, hand, arm png
      832x1950px
      527.27KB

    • Active undergarment Thigh Thigh Physical fitness Knee, healthy body, arm, fitness Professional, shoe png
      280x906px
      259.41KB

    • women measuring their waist, Human body Weight loss Waist surgery Detoxification Ms. thin waist sports and fitness, fitness, swimsuit Top, sports png
      763x1127px
      889.9KB

    • Bodybuilding Physical fitness Training Muscle mass, jasmine, sport, fitness Professional, arm png
      726x700px
      107.62KB

    • man standing in white underwear, Legs Legs, leg, people, leg, ankle png
      800x1198px
      457.65KB

    • Skeletal muscle Muscular system Human skeleton Human body, skeleton, hand, human, bodybuilder png
      586x468px
      256.28KB

    • Muscle Homo sapiens Human anatomy Human back, arm, people, human, fictional Character png
      1200x1200px
      1.07MB

    • Vertebral CNS Neuron Vertebral column, Brain, face, hand, people png
      707x1080px
      687. 19KB

    Dermatoma What is it, types and clinical significance / Anatomy and Physiology | Thpanorama

    dermatoma is a skin area innervated by a single spinal nerve. In particular, they are controlled by sensory neurons that arise from the ganglion of the spinal nerve.

    There are eight cervical nerves, twelve thoracic nerves, five lumbar nerves and five sacral nerves. Each of these nerves allows us to feel temperature, touch, pressure, and even pain.

    Information moves from a certain area of ​​the skin to the brain. The dermatomes are organized as a stack of discs in parts of the thorax and abdomen, with each disc supplied with a different spinal nerve. Thus, dermatomes run along the arms and legs in a longitudinal direction. Thus, each half of each limb has its own dermatome.

    Although all people usually have the same general pattern in the organization of dermatomes, specific areas of innervation can differ in each person, as if they were fingerprints.

    The spinal column has over 30 different vertebrae, which are divided according to their location, from the neck to the coccyx. They are classified as cervical, thoracic, lumbar and sacral. Each vertebra contains a specific spinal nerve that will innervate specific areas of the skin.

    All nerves except the first cervical nerve (C1) are associated with the dermatome. Dermatomes make it possible to map the spinal cord, which is very useful for medical professionals and researchers. And also for the diagnosis and treatment of pathologies.

    There are currently two main cards accepted in the medical profession. The first is Keegan and Garrett’s 1948 map and the second is Förster’s 1933 map, the latter being the most widely used..

    What is a dermatome?

    Have you ever wondered why back pain leads to tingling in the legs? Or why do neck cramps make you feel numb in your fingers?

    Apparently, this is due to the fact that there is a connection between sensations and disturbances on the surface of the skin with specific nerve roots that originate in the spine. Therefore, each region that is innervated by each of these nerve roots is called a dermatome..

    Dermatoma is subdivided into dermat, meaning skin, and oma, meaning mass. We have 29 dermatomes in the human body. These nerves are connected to each other since they originated from the same somite groups during embryonic development. Somites are structures formed on the sides of the neural tube during the fourth week of human development.0085

    Dermatomes should not be confused with myotomes. On the other hand, myotomes are those that innervate the skeletal muscles of the same group of somites. Each dermatome is classified according to the spinal nerve that innervates it. That is, the seventh cervical nerve innervates the C7 dermatome.

    This dermatome sensitizes the skin of the shoulder, some parts of the arm, and the index and ring fingers..

    Cervical dermatomes

    They nourish the skin of the neck, neck, back, arms and hands.

    Thoracic dermatomes

    They cover the skin of the inner arm, chest, abdomen and mid back.

    Lumbar dermatomes

    Innervate the skin that is located in the lower back, in the frontal area of ​​the legs, outer thighs and in the upper and lower parts of the legs.

    Sacral dermatomes

    They cover the skin of the genital and anal regions, the back of the legs, the back of the thighs and calves, in addition to the outer edge of the legs.

    However, it is important to note that dermatomes have been discovered in recent years by clinical observations and are only a guideline. Each person can present small changes within the dermatomes.

    Clinical significance

    It is important to know how dermatomes work clinically to localize nerve or spinal cord lesions. , it could be something to do with the nerve root. For example, a herniated disc that compresses the L5 nerve root results in pain and tingling in the lower leg and foot.

    Dermatomes are useful in the diagnosis and treatment of various conditions. The main ones are viral diseases, radiculopathy and spinal cord injuries. This virus is hidden in the spinal cord, and when it manifests itself, it moves through the spinal cord, causing a painful rash on the skin that is associated with this nerve..

    Herpes zoster is usually limited to a specific dermatome, such as the chest, leg, or arm. Usually appears years and even decades after recovery from chickenpox.

    radiculopathy

    This condition consists of pain caused by damage to the root of any nerve. It can also lead to loss or decrease in sensory function. The most common regions affected are L5 and S1, and less commonly C6 and C7.

    Pain is aggravated when we put ourselves in a position that stretches the roots of the nerves. It can be cervical or lumbar depending on where the pain is.

    Spinal Cord Injury

    When there is spinal cord injury, the healthcare professional will look for the affected dermatitis.