International Standards for the Classification of Spinal Cord Injury Motor Exam Guide

Flashcards covering key muscles, testing actions, palpation points, and common substitutions for spinal cord injury motor exams according to International Standards.

C5 Key Muscles

Elbow flexors: Biceps brachii and brachialis.

C5 Grade 3 Action

The patient attempts to move through the full range of motion in elbow flexion while the shoulder is in neutral and forearm is in full supination.

C6 Key Muscles

Wrist extensors: Extensor carpi radialis longus and extensor carpi radialis brevis.

C6 Common Muscle Substitution

Wrist extension can be mimicked by forearm supination and the use of gravity.

C6 Grade 0, 1 & 2 Palpation

For trace function, palpate the radial wrist extensors just proximal to the wrist on the radial aspect of the distal forearm.

C7 Key Muscle

Elbow extensors: Triceps.

C7 Common Muscle Substitution

Elbow extension can be mimicked by externally rotating the shoulder, by quickly flexing the elbow and then relaxing, and with spasticity of the triceps.

C7 Grades 0 & 1 Palpation

For trace function, palpate the distal triceps at its insertion on the olecranon.

C8 Key Muscle

Long finger flexors: Flexor digitorum profundus.

C8 Grade 3 Action

The patient attempts to flex the distal interphalangeal ($DIP$) joint of the isolated middle finger through the full range of motion.

C8 Tenodesis Movement

Involuntary movement of the distal phalanx occurring during active wrist extension, which can be misinterpreted as voluntary contraction of long finger flexors.

T1 Key Muscle

Small finger abductor: Abductor digiti minimi.

T1 Common Muscle Substitution

Finger extension can mimic $5\text{th}$ finger abduction.

L2 Key Muscle

Hip flexors: Iliopsoas.

L2 Acute Traumatic Lesion Precautions

When examining a patient with a lesion below $T8$, the hip should not flex beyond $90^\text{o}$ to avoid kyphotic stress on the lumbar spine.

L2 Grade 1 Palpation

The examiner palpates superficial hip flexors (sartorius and rectus femoris) because the iliopsoas insertion is too deep to feel at this strength.

L2 Common Muscle Substitution

Any muscle of the trunk that can elevate or rotate the pelvis, such as the rectus abdominus, adductors, obliques, or quadratus lumborum.

L3 Key Muscle

Knee extensors: Quadriceps.

L3 Grade 3 Action

The patient attempts to straighten the knee through the full range of motion from a starting position of approximately $30^\text{o}$ of flexion.

L4 Key Muscle

Ankle dorsiflexors: Tibialis anterior.

L4 Common Muscle Substitution

Ankle dorsiflexion can be mimicked by long toe extensors, particularly the extensor hallucis longus.

L5 Key Muscle

Long toe extensors: Extensor hallucis longus.

L5 Common Muscle Substitutions

Great toe extension can be facilitated by plantarflexion (tenodesis) or by active flexion followed by passive relaxation.

S1 Key Muscles

Ankle plantarflexors: Gastrocnemius and soleus.

S1 Grade 3 Action

The patient pushes the forefoot downward into the examiner's hand and raises the heel off the exam table through a full range of motion.

S1 Common Muscle Substitution

The examiner must visually monitor the hip flexors to ensure they are not being used to facilitate plantarflexion.