Diagnostic Guide to Neurological Levels
Motor Power
 Interruption of the nerve root causes denervation and
paralysis of its myotome.
 Pressure on a nerve root can cause a decrease in
muscle strength.
 Muscle testing is utilized to evaluate whether or not a
lesion is present and to what degree it is effecting the
muscle strength.
Muscle Grading Chart
 Muscle gradations
 5 – normal
 Description.
 Complete range of motion
 4 – good

 3 – fair

 2 – poor

 1 – trace

 0 - zero

against gravity with full
resistance.
Complete range of motion
against gravity with some
resistance.
Complete range of motion
against gravity.
Complete range of motion with
gravity eliminated.
Evidence of slight contractility.
No joint motion.
No evidence of contractility.
Sensation
 Pathology to the cord or nerve root results in loss of
light touch, followed by loss of sensation of pain.
 During recovery from nerve root injury, sensation of
pain returns before light touch.
Sensation
 The 2 sensations are tested separately, light touch
with a cotton swab, pain with pinpricks.
 Pinwheels can be utilized to evaluate sensation.
 Results can be recorded on a dermatome chart as
normal, hyperesthetic (increased), hypoesthetic
(decreased), dyesthetic (altered), or anesthetic
(absent).
Reflex
 Interruption in the basic reflex arc results in the
loss of reflex, while pressures on the nerve root
itself may decrease its intensity (hyporeflexia).
 Interruption of the upper motor neuron’s
regulatory control results in a hyperactive nerve
(hyperreflexia).
 Reflexes should be reported as normal, increased,
or decreased utilizing bilateral comparison.
Stretch Reflex Arc
Nerve Root Lesions by Neurologic
Level
Upper Extremity
Cervical Spine
 C5 is the 1st significant contribution to the brachial
plexus.
 C1-4 are difficult to test; However, C4 is the major
innervation to the diaphragm (via the phrenic nerve).
The Cervical Spine
Deltoid & Supraspinatous
Elbow Flexion and Extension
Biceps Brachii & Brachialis
Functions of the Biceps
Muscle Test for the Biceps
Biceps Reflex Test
Memory Trick
Muscle Test Shoulder Abduction
Sensory Distribution C5
Wrist Extension and Flexion
Extensor Carpi Ulnaris (Left),
Extensor Carpi Radialis (Right)
Muscle Test Wrist Extension
Brachioradialis Reflex Test
Memory Trick
Triceps Brachii
Walking With a Crutch Utilizes
the Triceps Muscle
Muscle Test Wrist Flexors
Flexor Carpi Radialis (Left),
Flexor Carpi Ulnaris (Right)
Finger Extension and Flexion
Extensor Digitorum
Muscle Test Finger Extension
Triceps Reflex Test
Flexor Digitorum Superficialis
(Left), and Profundus (Right)
Lumbricales
Muscle Test Finger Flexors
Memory Trick
Finger Abduction and
Adduction
Muscle Test Finger Abduction
Muscle Test Finger Adduction
Summary of Muscle Testing for
the Upper Extremity
Summary of Reflex Testing for
the Upper Extremity
Summary of Sensation for the
Upper Extremity
Cervical Vertebrae and Nerve
Roots
Herniated Cervical Disc
Occiput & C1 Articulation
C1 and C2 Articulation
Anatomic Basis for Posterior
Cervical Disc Herniation
Neurologic Levels in Upper
Extremity
 Motor
 C5 – shoulder abduction
 C6 – wrist extension
 C7 – wrist flexion and finger extension
 C8 – finger flexion
 T1 – finger abduction, adduction
Neurologic Levels in Upper
Extremity
 Sensation
 C5 – lateral arm
 C6 – lateral forearm, thumb, and index finger
 C7 – middle finger (variable)
 C8 – medial forearm, ring, and small finger
 T1 – medial arm
 T2 - Axilla
Neurologic Levels in Upper
Extremity
 Reflex
 C5 – biceps
 C6 – Brachioradialis
 C7 - triceps
Whiplash Injury to the Cervical
Spine
Anatomy of a Cervical Vertebrae
Orthopedic Tests Cervical Spine
 Valsalva test
 Distraction test
 Compression test
Valsalva Test
Distraction Test
Compression Test
Thoracic Spine
Beevor’s Spine
Hip Flexion
Iliopsoas
Muscle Test Iliopsoas
Knee Extension
Rectus Femoris (Left), Vastus
Intermedius and Lateralis
(Right)
Extension Lag
Muscle Test Quadriceps
Hip Adduction
Adductors
Muscle Test Hip Adductors
Dermatomes of the Lower
Extremity
Foot Inversion
Muscle Test Tibialis Anterior
Patellar Tendon Reflex
Memory Trick
Foot Dorsiflexion (Ankle
Extension)
Extensor Hallucis Longus
Muscle Test Extensor Hallucis
Longus
Muscle Test Toe Extensors
Memory Trick
Hip Abduction
Gluteus Medius
Muscle Test Gluteus Medius
L5 Sensory Dermatome
Foot Eversion
Peroneus Longus & Brevis
Muscle Test Peronei Muscles
Foot Plantarflexion
Gastrocnemius & Soleus
Muscle Test Gastrocnemius
Hip Extension
Gluteus Maximus
Muscle Test Gluteus Maximus
Achilles Reflex Test
Memory Trick
Sensory Dermatomes S2, S3, S4,
S5
Sensory Dermatomes L4-S1
Testing Sensation
Anatomic Basis for Posterior
Lumbar Disc Herniation
Neurologic Levels in Lower
Extremity
 Motor
 L3 – quadriceps (L2, L3, L4)
 L4 – Tibialis anterior
 L5 – toe extensors
 S1 - Peronei
Neurologic Levels in Lower
Extremity
 Sensation
 T12 – lower abdomen just proximal to inguinal ligament
 L1 – upper thigh just distal to inguinal ligament
 L2 – mid thigh
 L3 – lower thigh
 L4 – medial leg – medial side of foot
 L5 – lateral leg – dorsum of foot
 S1 – lateral side of foot
 S2 – longitudinal strip, posterior thigh
Neurologic Levels in Lower
Extremity
 Reflex
 L4 – patellar
 L5 – Tibialis posterior (difficult to obtain)
 S1 – Achilles tendon