Median Nerve

Authors

Affiliations

Nathaniel Yomogida, B.S., SPT

Doctor of Physical Therapy

B.S. in Kinesiology

Chloë Kerstein, B.S., SPT

Doctor of Physical Therapy

B.A. in Neuroscience

Origin

C6-T1¹

Motor Branches

Median n. Muscle Innervations
Muscle	Origin	Insertion	Innervation	Action

Direct Muscular branches of Median N.
Muscle	Origin	Insertion	Nerve	Action
Pronator Teres	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/pronator_teres.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/pronator_teres.html#insertion	?var:ref-pronator-teres.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/pronator_teres.html#action
Flexor Carpi Radialis	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_carpi_radialis.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_carpi_radialis.html#insertion	?var:ref-flexor-carpi-radialis.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_carpi_radialis.html#action
Palmaris Longus	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/palmaris_longus.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/palmaris_longus.html#insertion	?var:ref-palmaris-longus.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/palmaris_longus.html#action
Flexor Digitorum Superficialis	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_digitorum_superficialis_FDS.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_digitorum_superficialis_FDS.html#insertion	?var:ref-flexor-digitorum-superficialis.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_digitorum_superficialis_FDS.html#action

Indirect Muscular branches of Median N. (via anterior interosseous n.)
Muscle	Origin	Insertion	Nerve	Action
Flexor Digitorum Profundus	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_digitorum_profundus_FDP.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_digitorum_profundus_FDP.html#insertion	?var:ref-flexor-digitorum-profundus.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_digitorum_profundus_FDP.html#action
Flexor Pollicis Longus	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_pollicis_longus.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_pollicis_longus.html#insertion	?var:ref-flexor-pollicis-longus.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/flexor_pollicis_longus.html#action
Pronator Quadratus	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/pronator_quadratus.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/pronator_quadratus.html#insertion	?var:ref-pronator-quadratus.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Forearm Anterior Compartment/pronator_quadratus.html#action

Recurrent br.¹

Indirect branches of Median N. (via recurrent br.)
Muscle	Origin	Insertion	Nerve	Action
Opponens Pollicis	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/opponens_pollicis.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/opponens_pollicis.html#insertion	?var:ref-opponens-pollicis.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/opponens_pollicis.html#action
Abductor Pollicis Brevis	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/abductor_pollicis_brevis.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/abductor_pollicis_brevis.html#insertion	?var:ref-abductor-pollicis-brevis.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/abductor_pollicis_brevis.html#action
Flexor Pollicis Brevis	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/flexor_pollicis_brevis.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/flexor_pollicis_brevis.html#insertion	?var:ref-flexor-pollicis-brevis.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/flexor_pollicis_brevis.html#action

Indirect Muscular brs. via common palmar digital nn.¹

Indirect branches of Median N. (common palmar digital nn.)
Muscle	Origin	Insertion	Nerve	Action
Lumbricals (Hand)	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/lumbrical_muscles_hand.html#origin	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/lumbrical_muscles_hand.html#insertion	?var:ref-lumbricals-hand.nerve	/The Archive/Anatomy/Skeletal Muscles/Upper Limb Muscles/Hand Muscles/lumbrical_muscles_hand.html#action

Sensory Branches

Articular brs.: Capsules of the elbow and wrist joints
Palmar br. of median n. (thenar eminence)
Communicating br. to ulnar n.
Common palmar digital nn.
Proper palmar digital nn.

Pathway

Branches off of the medial and lateral cords just distal to the coracoid process
Enters the axilla into the anterior compartment
In the medial brachium, the median nerve travels with the brachial artery along the medial intermuscular septum
Crosses the elbow in the cubital fossa medial to the biceps tendon and brachial artery
Dives between the heads of the pronator teres into the anterior compartment of the antebrachium
Passes through the fibrous arch of flexor digitorum superficialis
Gives off the Anterior Interosseous Nerve
Dives deep to the flexor/pronator mass descending the antebrachium in the anterior compartment
Runs along the anterior surface of the interosseus membrane
Terminates in the anterior capsule of the carpals
Median nerve continues down the antebrachium deep to flexor digitorum superficialis and superficial to flexor digitorum profundus
Crosses the wrist at the carpal tunnel where it branches into the RECURRENT BRANCH and PALMER DIGITAL BRANCH of the median nerve.

Entrapment Sites

Ligament of Struthers
Pronator Teres Syndrome
Anterior Interosseous Syndrome
Carpal Tunnel Syndrome

Ligament of Struthers

Ligament of Struthers: present in 1% of population and is an alternate attachment site of the pronator teres (rather than the medial epicondyle). The ligament is found at the distal- medial humerus near the Arcade of Struthers -May include sensory and motor loss in a median nerve distribution. Muscles receiving motor innervation from both the median nerve and the anterior interosseous nerve will be affected as this entrapment is proximal to the any peripheral branching. -Can include vascular symptoms due to brachial artery passing under ligament along with nerve

Tinnel’s over the median nerve at the Cubital Fossa (here the nerve lies medial to the brachial artery and biceps Tendon)

Pronator Teres Syndrome

Pronator Teres Syndrome: Entrapment as it passes through the two heads of pronator teres

Same motor and sensory loss as described above Mechanical compression over the pronator teres muscle

Anterior Interosseous Syndrome

Anterior Interosseous Syndrome: Entrapment after the anterior interosseous nerve branches off of the median nerve

Clinical Presentation

Motor impairment in the pronator quadratus, medial 1⁄2 of FDP and flexor pollicis longus
No sensory loss

Testing

“Okay” Sign: when asked to make an “okay” symbol, a patient will demonstrate pad- to-pad approximation of the distal phalanx of the first and second digits rather than tip- to-tip contact (due to weak of the FDP & FPL)

Carpal Tunnel Syndrome

Entrapment within carpal tunnel
Very common

Clinical Presentation

Sensory loss over the palmar surface of the hand in a median nerve distribution
Can have motor weakness of thenar muscles and 1⁄2 lumbricals

Evaluation

Tinel’s at carpal tunnel

Examination

Wrist Flexion and Median Nerve Compression²
Median Nerve Compression Test/Pressure Provocation Test.
- The clinician sits opposite to the patient and holds the patient’s hand with the clinician’s thumbs directly over the course of the median nerve as it passes under the flexor retinaculum between the FCR and the palmaris longus. The clinician places gentle sustained pressure with the thumbs for 15 seconds to 2 minutes. The clinician then removes the pressure and questions the patient on the relief of symptoms, which may take a few minutes. A positive test is the reproduction of pain, paresthesia, or numbness distal to the site of compression during the compression in the distribution of the median nerve.²
ULTT1
ULTT2a
Phalen’s Test
Reverse Phalen’s
Tinel’s Test

Strain Counterstrain

References

Gilroy AM, MacPherson BR, Wikenheiser JC, Voll MM, Wesker K, Schünke M, eds. Atlas of Anatomy. 4th ed. Thieme; 2020.

Dutton M. Dutton’s Orthopaedic Examination, Evaluation, and Intervention. 5th ed. McGraw Hill Education; 2020.

Citation

For attribution, please cite this work as:

Yomogida N, Kerstein C. Median Nerve. https://yomokerst.com/The Archive/Anatomy/Nerves/Upper extremity nerves/median_nerve.html