Home Functional Hallux Limitus Diagnosis Clinical tests
Diagnosis
Clinical tests to identify FHL
The diagnosis of Functional Hallux Limitus is established at the clinical examination thanks to a specific three-phase test — the FHL stretch test — complemented by nine suggestive signs recognizable without any special equipment.
Diagnosis section
The reference test for FHL
Unlike many foot conditions, FHL shows up neither on X-ray, nor on MRI, nor on static examination. A specific dynamic test is needed to reveal it. This test, the FHL stretch test, is the key to the clinical diagnosis. It is performed in the office, without equipment, in three standardized phases.
The FHL stretch test — clinical demonstration
Reference test
FHL stretch test n.
A three-phase clinical test that assesses the ability of the first metatarsophalangeal joint of the big toe (MTP1) to extend when the ankle is placed in maximal dorsiflexion. A positive test (inability to extend the big toe) demonstrates the blockage in the gliding of the Flexor Hallucis Longus tendon in the retro-talar tunnel.
The three-phase protocol
The test is performed with the patient supine on an examination table. Each phase must be followed in order for the result to be reliable.
FHL stretch test
Three successive phases — about 30 seconds per side
Check the mobility
Patient lying on their back, ankle in plantarflexion. Confirm the free mobility of the MTP1 at rest.
Apply tension
Ankle placed in maximal dorsiflexion by firm pressure under the first metatarsal rays, using the palm of the hand and body weight.
Attempt extension
Apply dorsiflexion to the MTP1 by pushing the toe backward. Resistance, or the absence of resistance, determines the result.
How to interpret the result
The result is binary and can be read immediately. The sensitivity of the test is high because it directly evaluates the pathophysiological mechanism of FHL.
Positive test
Impossible to push the toe
The big toe stays blocked despite the pressure. The test demonstrates the blockage in the gliding of the FHL tendon in the retro-talar tunnel. The diagnosis of FHL is made.
Negative test
Extension of the toe is possible
The big toe extends normally. The FHL tendon glides correctly in its tunnel. No FHL — the assessment points to a different etiology.
A note for the clinician
The test should be performed bilaterally, even when symptoms are unilateral. FHL is frequently bilateral, and comparing the two feet helps to objectively demonstrate an asymmetry in mobility.
The vacuum cleaner cord maneuver as a corollary
When the test comes back positive, a specific maneuver makes it possible to restore the tendon’s gliding and to confirm the mechanism. Developed at the Centre Orthopédique d’Ouchy, it consists of mobilizing the subtalar joint through traction along the axis of the leg with small shearing movements. An articular click signals the unlocking. The tendon then regains room to glide.
The patient perceives this release as a tension in the calf, along the FHL muscle, or sometimes in the retromalleolar region at the musculotendinous junction. The maneuver is both diagnostic (it confirms FHL) and therapeutic (it temporarily frees the tendon).
Understanding the vacuum cleaner cord maneuver
The full detail of this signature maneuver, its biomechanical principle and its role in conservative treatment.
Scientific reference
The FHL stretch test and the vacuum cleaner cord maneuver were formally described in an international publication in 2010, which remains the reference for teaching the technique.
Foundational article
Functional Hallux Limitus or Rigidus Caused by a Tenodesis Effect at the Retrotalar Pulley — description of the Functional Stretch Test and the Hoover Cord Maneuver
Vallotton J., Cheverri S., Dobbelaere-Nicolas V., 2010, Journal of the American Podiatric Medical Association, vol. 100, no. 3, pp. 220–229.
« A simple test, in three phases, performed in less than a minute, is enough to reveal a dysfunction that may have blighted a patient’s life for years. »
Centre Orthopédique d’Ouchy
Nine other suggestive clinical signs
In addition to the stretch test, several clinical signs observable on examination or inspection point strongly toward FHL. Their combined presence strengthens the diagnostic suspicion before or after performing the test.
FHL tendon painful on palpation under the sole
Hyperkeratosis on the medial aspect of the pulp of the big toe
Compensatory hyperextension of the interphalangeal joint
Absence of callus under the head of the first metatarsal
Marked callus under the head of the fifth metatarsal
Clawing of the second toe
Blockage of the subtalar joint
Wear of the shoe on the lateral side of the heel
Wear of the sock or insole under the pulp of the big toe
For professionals
These signs are not pathognomonic taken in isolation, but their combination strengthens the suspicion. The presence of three or more signs in a symptomatic patient justifies performing the stretch test, even in the absence of local pain in the big toe.
Video demonstration
In addition to the stretch test demonstration shown at the top of the page, this video sequence shows the vacuum cleaner cord maneuver as it is performed at the Centre Orthopédique d’Ouchy.
The vacuum cleaner cord maneuver
Next step
If the test is positive, what next?
The diagnosis is made. The next step is to objectively demonstrate the biomechanical compensations through the mobility assessment and to guide management.
In practice
Test duration
< 1 min
Position
supine
Equipment required
none
Phases
3
Associated signs
9
Performed
bilaterally