Home Functional Hallux Limitus Diagnosis Gait analysis
Diagnosis
Gait analysis, the tool that reveals FHL in motion
The foot is the organ of balance. With every step, it tilts into pronation and then supination in a precisely timed choreography that FHL disrupts. Gait analysis is the tool that makes this disruption visible, from a simple in-office examination to the instrumented walking treadmill.
Diagnosis section
The foot, organ of balance
The foot is not just a weight-bearing platform. It is, by definition, the organ of balance, and its role in walking is to orchestrate a choreography of alternating tilts between pronation and supination, synchronizing the entire lower limb up to the spine. With every step, this ballet must unfold in the right order, at the right moment, without a jolt. FHL breaks this choreography.
The physiological cycle in three phases
Before understanding how FHL derails gait, one must know the normal sequence. The physiological cycle breaks down into three coordinated phases in the transverse plane, which provide shock absorption, propulsion and stability.
Physiological pronation-supination cycle
Three successive phases, each with a precisely codified tilt of the foot.
Heel strike
The foot strikes the ground in slight supination or in a neutral position, then tilts into supination at the beginning of stance.
Stance phase
The foot flattens, then tilts into pronation to absorb the impact and adapt the support to the ground.
Propulsion
The foot returns to supination, the big toe rises into dorsiflexion, and the foot becomes a rigid propulsive lever.
A sequence synchronized with the whole body
This sequence is synchronized with the rest of the body. Pronation drives internal tibial rotation, supination drives external tibial rotation, and the pelvis pivots in cadence. Everything is linked, automatic, efficient.
The right image, a boat hull riding the wave
To visualize this movement, the most accurate image is that of a boat hull rolling in the wave. The foot tilts alternately from one side to the other, in a codified and supple rhythm that absorbs stresses and distributes loads across the joints. It is this controlled rolling that makes human walking efficient and fluid.
The teaching analogy
The foot as a boat hull
When walking, the foot rolls through pronation and supination in a codified rhythm. Like a boat hull leaning from one side to the other in the wave, the foot absorbs, distributes and propels with suppleness. FHL disturbs this rolling motion, making it abrupt and disorganized, and breaks the rhythm. The movement loses its fluidity, and the body can no longer glide through the step like a boat over water.
How FHL disrupts the fine mechanics
FHL shifts the timing of the transitions between pronation and supination. The result is exaggerated supination at heel strike and, above all, exaggerated and abrupt pronation at the end of the stance phase. Where the foot should tilt smoothly, there is a true break in the movement.
The long-term effect
A break repeated millions of times a year
With about 5 million walking cycles per year per individual, this imbalance repeats itself millions of times. The abrupt break at the end of stance increases joint loads with every step, produces a destabilizing rolling effect that can trigger serious injuries such as ACL rupture, and sustains overload lesions at every level of the lower limb.
The three-level gait examination
Gait analysis is performed progressively, from the simplest to the most precise. Three complementary levels of examination allow the clinician to objectify the disorders according to the clinical context and the needs of the diagnosis.
Level 1 — Office
Visual examination at the consultation
- A few steps are enough to show a sweeping effect
- Revealing single-leg balance tests
- A tilt into pronation often points to FHL
- Examination of the shoes (asymmetric wear)
Level 2 — Treadmill
Dynamic analysis on an instrumented treadmill
- Inability to dorsiflex the big toe
- Direct signature of the tenodesis effect
- Video capture + plantar pressure measurement
- Reveals anomalies invisible to the naked eye
Level 3 — Running
Running analysis for athletes
- Accentuates the deficits observed when walking
- Reveals the repercussions higher up the chain
- Essential for athletes
- Objectifies the loads imposed on the foot
Four observable consequences on gait analysis
In patients with FHL, gait analysis objectifies a disturbance of the foot roll-through that remains invisible on static examination. Four biomechanical consequences are systematically found and constitute a major diagnostic cluster.
- Reduced ground contact time on the FHL side
- The patient tries to shorten a painful or inefficient stance
- Weight shifts too quickly onto the opposite forefoot
- Load asymmetry measurable on an instrumented treadmill
- Compensation for the lack of propulsion
- Disturbance of the coxa pedis synchronism
- Broken subtalar / hip synchronism
- This break is measurable and objectively signs FHL
The diagnostic contribution
These anomalies are documented by video and by pressure platform. They constitute a major criterion in the diagnosis of FHL, particularly in cases where the in-office clinical test is not enough to convince the patient or to objectify the functional impact.
The repercussions visible at the lumbo-pelvic level
Gait analysis is not limited to observing the foot. It also makes it possible to visualize the effect of FHL on overall posture, particularly at the lumbo-pelvic level. Striking the step in external rotation reduces the lever arm of the gluteus medius and causes a contralateral pelvic drop during the stance phase. This drop is directly visible on video and explains why FHL reverberates all the way up to the back.
« A few steps are enough to tell what years of symptoms have failed to reveal. Gait analysis is the most immediate revealer of FHL. »
Dr Jacques Vallotton, Centre Orthopédique d’Ouchy
Understand it on video
FHL: involvement of FHL in gait and posture disorders — Dr Jacques Vallotton
The value of instrumented gait analysis — Margaux Baron
Next step
Complete it with the podiatric analysis
Gait analysis is ideally complemented by a static and dynamic podiatric assessment, which measures plantar pressures and the footprint on the ground.
At a glance
Phases of the cycle
3
Levels of examination
office, treadmill, running
Reference tool
instrumented treadmill
Key sign
abrupt break at late stance
Cycles per year
5 million
Possible measurements
pressures, video
Going further
Related pages
Podiatric assessment
The static and dynamic analysis of plantar pressures, an essential complement to gait analysis.
Clinical tests
The FHL stretch test, the reference in-office examination, complementary to the dynamic analysis.