Clinical Testing of Spinal Nerves Flashcards
Describe somatic general sensory supply of spinal nerves.
- Provided by sensation specific receptors in all body wall structures.
What senses are experienced via somatic general sensory supply?
- Touch.
- Temperature.
- Proprioception.
- Vibration.
- Pain.
Describe somatic motor function of spinal nerves.
Somatic motor axons synapse on all body wall skeletal muscle fibres - e.g. to enable locomotion.
Describe sympathetic motor function of spinal nerves.
- Motor supply to organs.
- Sympathetic axons carried on spinal nerves.
- Synapse on the glands of the body wall and smooth muscle fibres.
What carries sympathetic axons?
Spinal nerves.
Where do sympathetic axons synapse?
- Body wall glands.
- Smooth muscle fibres.
How do spinal reflexes arise?
Spinal cord allows for segmental synapses between somatic sensory axons and somatic motor axons.
Where do posterior rami supply skin?
Central strip down the back and posterior neck.
Anterior rami form which plexuses?
- Cervical.
- Brachial.
- Lumbar.
- Sacral.
The lower anterolateral trunk wall is supplied by what nerves?
Iliohypogastric and ilioinguinal.nerves.
Iliohypogastric and ilioinguinal nerves are formed from the anterior ramus of which spinal nerve?
L1
Femoral nerve roots.
L2-L4.
What type of axons are found in the femoral nerve?
- Sensory, motor and sympathetic.
How many true dermatomes does the area of cutaneous innervation of the femoral nerve cross?
L2-4 i.e. 3 true dermatomes.
Anterolaterally, the neck skin is supplied by what?
Cervical plexus.
Cervical plexus arises from anterior rami of which spinal nerves?
C1-4.
Posterior neck and scalp skin is mainly supplied by the posterior rami of which spinal nerves?
C2-C8.
What is the “nerve point” of the neck?
Where sensory nerves of cervical plexus converge ans pass from superficial to deep fascia.
Where is the “nerve point” of the neck found?
At the midpoint of the posterior border of sternocleidomastoid.
What supplies the skin posterior to the external ear?
Lesser occipital branch of C2.
What supplies the skin over the angle of the mandible and some of the external ear?
Great auricular nerve - C2,3.
What supplies the skin over the anterior neck?
Transverse cervical C2,3.
What supplies the skin over the clavicle and the “shoulder tip”?
Supraclavicular nerves C3,4.
What nerve is responsible for the referred pain from the diaphragm to the shoulder?
Supraclavicular nerves C3,4.
LITTLE GOATS TREAD SOFTLY.
- Lesser occipital.
- Greater auricular.
- Transverse cervical.
- Supraclavicular.
- Named nerve cutaneous innervation of anterolateral neck.
The anatomical snuff box is supplied by the cutaneous branches of which nerve?
Radial nerve.
Radial nerve roots.
C5-T1.
Anterior rami of which nerve roots are important for referred pain from the myocardium?
T1 and T2.
When testing sensory function of a peripheral nerve, to which part of the spinal cord does the action potential ultimately enter?
Posterior horn.
What should you examine to test the C1-4 motor axons (myotomes) of the cervical plexus?
- Neck postural and strap muscles.
- Diaphragm.
What should you examine to test the C5-T1 motor axons (myotomes) of the brachial plexus?
- Muscles of the upper limb.
- Extrinsic back muscles that move the upper limb or scapula.
What should you examine to test the motor axons (myotomes) of T2-L3?
- Postural back muscles (posterior rami).
- Intercostal muscles (anterior rami).
- Anterolateral abdominal wall muscles.
Motor axons of the Lumbosacral plexus L1-S4 supply what?
- Muscles of the lower limb.
- Perineal skeletal muscles.
The area of motor innervation of the femoral nerve crosses how many true myotomes?
3.
- L2, L3 and L4 spinal nerves.
How to test C5 myotome?
Shoulder abduction.
Which muscle is tested for C5 myotome (shoulder abduction)?
Deltoid.
How to test C6 myotome?
Elbow flexion.
Which muscle is tested for C6 myotome (elbox flexion)?
Biceps brachii.
How to test the C7 myotome?
Elbow extension.
Which muscle is tested for C7 myotome (elbow extension)?
Triceps brachii.
How to test the C8 myotome?
Finger flexion.
Which muscle is tested for C8 myotome (finger flexion)?
Flexor digitorum superficialis.
How to test the T1 myotome?
Finger abduction.
Which muscle is tested for T1 myotome (finger abduction)?
Dorsal interossei.
How to test the L3 myotome?
Knee extension.
Which muscle is tested for L3 myotome (knee extension)?
Quadriceps femoris.
How to test the L4 myotome?
Ankle dorsiflexion.
Which muscle is tested for L4 myotome (ankle dorsiflexion)?
Tibialis anterior.
How to test the L5 myotome?
Great toe extension.
Which muscle is tested for L5 myotome (great toe extension)?
Extensor hallucis longus.
How to test the S1 myotome?
Ankle plantarflexion.
Which muscle is tested for S1 myotome (ankle plantarflexion)?
Gastrocnemius.
How to test the S2 myotome?
Knee flexion.
Which muscle is tested for S2 myotome (knee flexion)?
Biceps femoris.
APs of peripheral nerves are generated by voluntary intention where?
Primary somatosensory cortex.
APs of peripheral nerves are conducted via what axons of the corticospinal tract?
Upper motor neuron axons.
APs of peripheral nerves continue alone UMN axons to which horn of the spinal cord?
Anterior.
UMN axons of peripheral nerves synapse with what to stimulate an AP?
LMNs.
With regards to peripheral nerves, after UMN synapse with LMN to stimulate APs, the AP then continues along axons to what?
Spinal nerve.
UMN lesions cause what?
Spasticity.
LMN lesions cause what?
Flaccidity.
Reflex testing of Biceps brachii tests what spinal levels?
C5 and C6.
Reflex testing of Triceps brachii tests what spinal levels?
C7.
Reflex testing of Brachioradialis tests what spinal levels?
C6.
Reflex testing of knee jerk tests what spinal levels?
L3
Reflex testing of ankle jerk tests what spinal levels?
S1
Name the peripheral nerve motor innervation to the muscles of facial expression.
CN VII.
Name the peripheral nerve motor innervation to the muscles of mastication.
CN V3.
Name the peripheral nerve motor innervation to the muscles of the tongue.
CN XII.
Name the peripheral nerve motor innervation to the muscles of the soft palate.
CN X (pharyngeal plexus).
Name the peripheral nerve motor innervation to the neck postural muscles.
Posterior rami of cervical spinal nerves.
Name the peripheral nerve motor innervation to the strap muscles of the neck.
Cervical plexus C1-3.
Name the peripheral nerve motor innervation to the diaphragm.
Phrenic nerve C3,4,5 from the cervical plexus.
Name the peripheral nerve motor innervation to the sternocleidomastoid and trapezius muscles.
CN XI.
Name the peripheral nerve motor innervation to the muscles of the pharynx.
CN X mainly.
Name the peripheral nerve motor innervation to the intrinsic muscles of the larynx.
CN X.
Name the peripheral nerve motor innervation to the intercostal muscles.
Intercostal nerves.
Name the peripheral nerve motor innervation to the anterolateral abdominal wall muscles.
Thoracoabdominal nerves.
Name the peripheral nerve motor innervation to the erector spinae and transversospinalis muscle groups.
Posterior rami of spinal nerves.
Axillary nerve is the named nerve motor innervation of which muscles in the upper limb?
Deltoid and teres minor.
Radial nerve is the named nerve motor innervation of which muscle in the posterior compartment of the arm?
Triceps brachii.
Radial nerve is the named nerve motor innervation of which muscles in the posterior compartment of the forearm?
- Brachioradialis.
- Supinator.
- ALL extensors of carpus and digits.
- Abductor pollicis longus.
Musculocutaneous nerve is the named nerve motor innervation of which muscles in the upper limb?
ALL of anterior compartment of arm.
- Biceps brachii.
- Brachialis.
- Coracobrachialis.
Musculocutaneous nerve has which spinal roots?
C5,6,7.
Axillary nerve has which spinal roots?
C5,6.
Radial nerve has which spinal roots?
C5-T1.
Median nerve is the named nerve motor innervation of which muscles in the anterior compartment of the forearm?
Anterior compartment of forearm.
- Pronator (teres and quadratus).
- Flexor carpi radialis.
- Palmaris longus.
- Flexor digitorum superficialis.
- Lateral half of flexor digitorum profundus.
- Flexor pollicis longus.
Median nerve is the named nerve motor innervation of which muscles of the hand?
- Thenar muscles.
- Lumbricals 1&2.
Median nerve has which spinal roots?
C5-T1.
Ulnar nerve has which spinal roots?
C7-T1.
Ulnar nerve is the named nerve motor innervation of which muscles in the anterior compartment of the forearm?
- Flexor carpi ulnaris.
- Medial half of flexor pollicis longus.
- Adductor pollicis.
Ulnar nerve is the named nerve motor innervation of which muscles of the hand?
- Hypothenar muscles.
- Lumbricals 3 & 4.
- ALL interossei, both dorsal and palmar.
Femoral nerve has which spinal roots?
L2-4.
Femoral nerve is the named nerve motor innervation to which muscles of the lower limb?
- Quadriceps femoris.
- Sartorius.
- Pectineus.
Obturator nerve is the named nerve motor innervation to which muscles of the lower limb?
ALL of the medial compartment of thigh.
- Obturator externus.
- Gracilis.
- Adductor brevis.
- Adductor magnus.
- Adductor longus.
Tibial division of the sciatic nerve is the named nerve motor innervation to which muscle groups of the lower limb?
- Posterior compartment of thigh.
- Posterior compartment of leg.
- Sole of foot.
Name the muscles of the posterior compartment of the thigh innervated by the tibial division of the sciatic nerve?
- Semimembranosus.
- Semitendinosus.
- Long head of biceps femoris.
Name the muscles of the posterior compartment of the leg innervated by the tibial division of the sciatic nerve?
- Gastrocnemius.
- Soleus.
- Plantaris.
- Popliteus.
- Tibialis posterior.
- Flexors of the digits.
Name the muscles of the sole of the foot innervated by the tibial division of the sciatic nerve.
ALL intrinsic muscles of the sole of the foot.
Spinal roots of tibial division of sciatic nerve?
L4-S3.
Spinal roots of common fibular division of sciatic nerve?
L4-S2.
Name the muscles of the lower limb receiving innervation via the common fibular division of sciatic nerve.
Short head of biceps femoris.
Name the muscles of the lower limb receiving innervation via the superficial fibular branch of the sciatic nerve.
Lateral compartment of leg:
- Fibularis longus.
- Fibularis brevis.
Name the groups of muscles of the lower limb receiving innervation via the deep fibular branch of the sciatic nerve?
- Anterior compartment of leg.
- Dorsum of foot.
Name the muscles of the anterior compartment of the leg receiving innervation via the deep fibular branch of the sciatic nerve.
- Tibialis anterior.
- Extensor digitorum longus.
- Extensor hallucis longus.
Name the muscles of the dorsum of the foot receiving innervation via the deep fibular branch of the sciatic nerve.
- Extensor digitorum brevis.
- Extensor hallucis longus.