There
are numerous restrictions that can alter gait. In the foot the key aspects are
(1) normal roll of the calcaneus (generally fine unless there has been trauma)
(2) adequate dorsiflexion (3) adequate mobility of the first metatarsal. It has
been well known for a long time that the mobility of the first metatarsal (hallux
rigidius) is required for normal gait. However in 1993 a podiatrist, Howard
Dannenburg, described a functional limitation of the first metatarsal which can
appear normal during a non weight bearing assessment, but limited during weight
bearing (e.g. gait). Functional
hallux limitus (FHL) is defined as a functional inability of the proximal
phalanx of the hallux to extend on the first metatarsal head during gait. The
theory concerning this anomaly and the altered gait patter that may result
appears to have influenced the understanding of sagittal plane biomechanics.
Although
podiatrists recommend orthotics to treat FHL, there is very obvious biological
plausibility that proximal rehab using specific motor control training of
gluteus maximus and posterior gluteus medius training (for hip external
rotation), and lower limb alignment can be used to treat it as well. One would
argue this is better since no orthotic is needed and aims to deal with the true
underlying cause of the problem.
But does
it?
Some
concerns:
·
The
diagnostic accuracy of the clinical test is lower than the traditional minimal level
of .80 that one would like in a diagnostic test (sensitivity
of 0.72 and a specificity of 0.66).
·
Over
20 years of very specifically rehabilitating gluteus maximus, posterior gluteus
medius and lower limb alignment plus integrating these into function has made
only small changes in FHL in some.
Can the presentation of FHL be
explained by a the presence of a primitive reflex?
The Foot
Tendon Guard is a primitive reflex that is essentially the evil twin of
Babinski (see below). It's presence explains the findings of FHL.
Interestingly, if you do the specific motor control training described above
you are aiming to take the sensory stimulus off the medial side of the foot
(Foot Tendon Guard) and place it on the outside (Babinski sensory stimulus
region). This is a classic example of where Neurology meets Orthopedics. The
Foot Tendon Guard is easily treated and benefits can be seen immediately in
most people.
·
Sensory
stimulus (Foot Tendon Guard)
o Medial side of the foot
o Distal to proximal
·
Motor
response
o Plantar flexion
o First toe flexion
o Hip extension
o Trunk extension
o Shoulder girdle depression
o Glenohumeral extension
o Elbow extension
o Wrist flexion
o Finger flexion
The
traditional view in neuro rehab when there is shoulder girdle tone during gait
is to assume it is there to fixate the pelvis to aim in lower limb movement,
however as we see here, the Foot Tendon Guard reflex (as well as Babinski) are
whole limb reflexes and the pressure of the foot can cause tone in the shoulder
girdle. So treating the foot reflexes will help gait.
Summary
The lack of
adequate dorsiflexion or first metatarsal extension can initiate widespread compensations
including altered movement in the foot, knee, hip, lumbo-pelvic region and
beyond as well as altering muscle recruitment. Therefore it is a clinical
priority to address and treat the root cause.
1.
Hip
extension
a. myofascial
b. articular
c. neural
d. Primitive Reflexes (e.g. Symmetrical Tonic
Neck Reflex, Moro Reflex, Asymmetrical Tonic Neck Reflex, Abdominal Reflex,
Babinski)
2.
Dorsiflexion
a. myofascial
b. articular
c. neural
d. Primitive Reflexes (e.g. Foot Tendon Guard,
Plantar Grasp, Heel Grasp)
3.
First
metatarsal extension
a. myofascial
b. articular
c. neural
d. Primitive Reflexes (e.g. Foot Tendon Guard,
Plantar Grasp, Heel Grasp)
Sean GT Gibbons BSc (Hons) PT, MSc Ergonomics, PhD (c),
MCPA
References
Payne C, Chuter V, and Miller K 2002 Sensitivity and Specificity of
the Functional Hallux Limitus Test to Predict Foot Function. Journal of the
American Podiatric Medical Association: May 2002, Vol. 92, No. 5, pp. 269-271. doi:
http://dx.doi.org/10.7547/87507315-92-5-269
HJ Dananberg 1993 Gait style as an etiology to chronic postural pain. Part I.
Functional hallux limitus. Journal of the American Podiatric Medical
Association: August 1993, Vol. 83, No. 8, pp. 433-441. doi: http://dx.doi.org/10.7547/87507315-83-8-433
Durrant B, Chockalingam N 2009 Functional
Hallux Limitus: A Review. Journal of the American Podiatric Medical Association.
May/June, Vol 99, No 3. 236-243
No comments:
Post a Comment