Test: Great Toe (Hallux) Extension Muscle Testing

Video Link

Background/Purpose

Hallux (1st toe) extension occurs due to the action of the Extensor Hallucis Longus (EHL) and the Extensor Hallucis Brevis(EHB) muscles. The EHL originates on the Middle half of the anterior shaft of the fibula and inserts on the base of the distal phalanx of the great toe. The EHB originates on the distal superior and lateral surface of the calcaneus and inserts on the dorsal surface of the proximal phalanx. Because of their positions, the EHL with extend the distal and proximal phalanx while the EHB will only extend the proximal phalanx. Innervation of the EHL occurs by the deep peroneal nerve which is a segment from the L5 nerve root. In a study by Hara, it was found that there is some discrepancy between toe extension of the metatarsalphlangeal joint (MTP) and the interphalangeal joint (IP) (Hara 2011). In the Hara study, they evaluated toe extension with MTP extension, IP phalanx extension, IP phalanx neutral and IP phalanx flexion. It was noted that testing at the MTP gave superior results to testing the IP in the three ranges. Because of the variability, it was recommended to asses toe extension using MTP extension as the standard until variations reasons can be determined. Although the Extensor Digitorum Brevis muscle belly (innervation: L5-S1) is adjacent to the EHB it is not known exactly what the innervation of the EHB is. Many patients will have difficulty separating toe extension from great toe extension(Muscle Testing 1995). The test is not necessarily to determine strength, but muscle activity (Muscle Testing 1995, Hara 2011).

Procedure

Subject is placed in a seated or supine position. The clinician sits or stands in front of or on the side of the subject. The clinician stabilizes the foot/metatarsals in a neutral position. Subject is told “Straighten your big toe”. The clinician uses the thumb or index finger to apply a pressure in the direction of toe flexion at the proximal phalanx.
Test results are recorded using the following scale:
5 Holds test position against maximal resistance
4+ Holds test position against moderate to strong pressure
4 Holds test position against moderate resistance
4- Holds test position against slight to moderate pressure
3+ Holds test position against slight resistance
3 Holds test position against gravity
3- Gradual release from test position
2+ Moves through partial ROM against gravity OR Moves through complete ROM gravity eliminated and holds against pressure
2 Able to move through full ROM gravity eliminated
2- Moves through partial ROM gravity eliminated
1 No visible movement; palpable or observable tendon prominence/flicker contraction
0 No palpable or observable muscle contraction

Performed: Unilaterally

Dialog

Subject extends great toe against clinician’s resistance.

Criteria

• Full Strength
• No pain

Measurement

0.00

LOINC Code

0

Scale/Grading

Pass/Fail