Orthopaedic Neurology 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 Description. 5 – normal 4 – good 3 – fair 2 – poor 1 – trace 0 - zero Complete range of motion 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), hyposthetic (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 Evaluation of Nerve Root Lesions 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