Muscle Test: Triceps | Hand Surgery Resource

Exams and Signs

Origin:	Long Head: Scapula (blends above with the capsule of the glenohumeral joint Lateral Head: Humerus (shaft: oblique ridge, posterior surface) Lateral intermuscular septum Medial Head: Humerus (shaft: entire length of posterior surface) Medial and lateral intermuscular septa Humerus (medial border)
Insertion:	All heads have a common tendon to: Ulna (olecranon process, upper surface); blends with antebrachial fascia capsule of elbow joint
Innervation:	Cervical root(s): C6–C8 Nerve: radial (ventral rami)

Grading of muscle strength:

Grade	Strength	Description
5*	Normal	Normal strength
4*	Good	Movement against external resistance but less than normal
3	Fair	Movement against gravity but not against added resistance
2	Poor	Movement at the joint with gravity eliminated
1	Trace	Trace of contraction but no movement at the joint
0	Zero	No contraction or muscle movement
*The distinction between Grades 4 and 5 is based on comparison with the normal hand and, barring that, extensive experience in testing the hand.

Position of patient's hand and upper extremity

The patient lies prone on a table and starts the test with the arm in 90° abduction and the forearm is flexed and hanging vertically over the table’s side. Some suggest that for Grades 0 and 1, the patient be seated with the arm abducted to 90° and the shoulder in neutral rotation and the elbow flexed to about 45°. The entire limb is horizontal to the floor.

Examiner’s Actions

For the prone patient, the examiner provides support just above the elbow, while using the other hand to apply downward resistance on the dorsal surface of the forearm. Some suggest that the examiner support the limb at the elbow, and that for Grades 0 and 1, the examiner also palpates the limb under the forearm and the triceps on the posterior surface of the arm just proximal to the olecranon process.

Instructions for the patient

“Straighten your elbow. Hold it. Don’t let me bend it.” Some suggest “Try to straighten your elbow” for Grades 0–2.

Presentation Photos and Related Diagrams

Definition of Positive Result

In muscle testing, a normal result is a positive one. During a normal muscle test, the examiner should observe a normal muscle contraction that can move the joint or tendon against full resistance.

Definition of Negative Result

In muscle testing, an abnormal result is a negative one. During an abnormal muscle test, the examiner should observe an abnormal muscle contraction that can move the joint or tendon. In a complete denervation injury, such as a complete nerve laceration, there will be no evidence of any muscle function and the muscle testing grade will be 0.

Comments and Pearls

The examiner should confirm that muscle activity is seen and felt because patients can become very adept at substituting.
Give resistance for Grades 4 and 5 with the elbow slightly flexed to avoid allowing the patient to “lock” the elbow joint by hyperextending it.
When testing elbow extension in the prone position, the examiner should be aware that with the shoulder horizontally abducted the two-joint muscle is less effective, and the test grade may be lower than it should be.
An alternative position to test Grades 3–5 is short sitting. The examiner stands behind the patient, supporting the arm in 90° of abduction just above the flexed elbow. The patient then straightens the elbow against the resistance given at the wrist.

Diagnoses Associated with Exams and Signs

Videos

Testing triceps strength by resisting and grading elbow extension.

References

Hislop JH, Avers D, Brown M. Daniels and Worthingham's Muscle Testing, Techniques of Manual Examination and Performance Testing. 9th ed. St. Louis, Missouri: Elsevier Saunders, 2014, pp. 138–202.
Kendall FP, McCreary EK, Provance PG. Muscles Testing and Function. 4th ed. Baltimore, MD: Williams & Wilkins, 1993, pp. 235–298