Protocol for recording Preimus Metatarsus Supinatus value

  • The foot is positioned into its' anatomical neutral position (e.g., that position where the articular facets of the subtalar joint are congruous)
  • A microwedge is slid underneath the first metatarsal head (white wedges in above animation)
  • The distance between the ground and the first metatarsal head is read and recorded (referred to as Primus Metatarsus Supinatus value)

​Posterior tibialis Syndrome (Acquired Adult Flat Foot)


The Posterior Tibialis Muscle is a major stabilizer of the rearfoot.  Rupture or chronic stretching of this muscle, beyond its normal limit of excursion, can lead to a functional flatfoot.  This acquired adult flat foot must be differentiated from the PreClinical Clubfoot Deformity which also results in a functional flatfoot.


Typical rupture point of this muscle is either at or within 6cm proximal to its navicular insertion.


Xray (See Below) frequently demonstrate:

  • Decreased calcaneal plantar angle
  • Increased lateral talometatarsal angle
  • Increased anterior talocalcaneal angle
  • Increased lateral talocalcaneal angle

Spring Ligament Laxity - ​can result in a functional flatfoot

Anatomy:  The Spring Ligament is a strong, thick ligament which covers part of the articular surface of the talar head. It is attached to the (1) anterior border of the sustentaculum tali and (2) plantar surface of the navicular.

Function:  The Spring Ligament helps maintain the inner longitudinal arch by supporting the head of the talus. Laxity of the Spring Ligament (as occurs in Ehlers-Danlos Syndrome and Marfan Sydrome) can result in a forward, downward and inward displacement of the talar head (See Fluoroscopy below)

Reference

​Cummings GS, Higbie EJ 1997.  A weight bering method for determining forefoot posting for orthotic fabrication.  Physio Research International, 2(1). Whurr Publishers Ltd.


Tarsal Coalition (See Photo below)

Discussion:

How the feet can lead to pain throughout the body:

1.  All feet have mechanical receptors on the bottom, which are stimulated through touch, as in standing or walking.  This stimulation produces a signal which is sent to the brain.

  • If the foot structure is normal, correct signals are sent to the cerebellum.  The cerebellum acts on these correct signals by maintaining good posture.
  • If the foot structure is abnormal (such as in a PreClinical Clubfoot Deformity), distorted signals are sent to the cerebellum.  The cerebellum acts on these distorted signals by maintaining  a distorted (bad) posture.


2.  Posture affects the health of all the weight-bearing joints/muscles and viscera in your body. Postural distortions (poor posture) misaligned the joints and can compress internal organs. Frequently, this leads to joint and muscle inflammation and visceral irritation. 

3.  If the postural distortions are not corrected, chronic disabling symptoms can develop.

PreClinical Clubfoot Deformity

Note the automatic and instantaneous postural correction when the appropriate proprioceptive insole is used to correct the proprioceptive signals to the cerebellum:

  • Anteriorly rotated innominates repositioned backwards towards their anatomical neutral position
  • Kyphotic curve is reduced
  • Shoulders retract
  • Forward head position attenuates

Gravity Drive Pronation observed in the PreClinical Clubfoot Deformity - Treadmill Analysis

The definition of abnormal pronation does not refer to the amount of pronation. Abnormal pronation refers to the timing of pronation.  That is, the foot is pronating when it should be supinating, e.g., it has escaped Hip Drive Pronation and becomes engaged in Gravity Drive Pronation.

  • At frame 05 the foot lifts straight up, e.g., lack of a propulsive toe-off
  • Frames 06 - 07, the foot (excessively) pronates until the entire plantar surface of the inverted calcaneus rests on the ground
  • Frames 09 - 11, the foot continues to pronate until the inverted first metatarsal and hallux rests on the ground.  This occurs while the ipsilateral (same side) hip is externally rotating (e.g., the foot has escaped Hip Drive Pronation and is exclusively engaged in Gravity Drive Pronation)

In 2002, I published a paper in the Journal of Bodywork and Movement Therapy describing a previously unrecognized embryological foot structure, the PreClinical Clubfoot Deformity, which occurs when the talus and calcaneus do not complete their normal ontogenetic development (e.g., Calcaneal and Talar Supinatus).

Clinically, Calcaneal and Talar Supinatus maintains the calcaneus and entire medial column of the foot in supinatus, observed as an elevated and inverted calcaneus, first metatarsal and hallux when the foot is placed into its anatomical neutral position (e.g., subtalar joint congruity).

The PreClinical Clubfoot Deformity is one of the most common causes of abnormal pronation. This occurs because gravity forces the gaiting foot to rotate inward and downward until the elevated and inverted calcaneus, first metatarsal and hallux rest on the ground (referred to as Gravity Drive Pronation).

Fluoroscopy of the Rearfoot. Laxity of the spring ligament predisposes the head of the talus to slip downward and forward. This can result in the partial or total collapse of the inner longitudinal arch.

Note the atypical heel contact in which the entire foot lands on the ground (as opposed to a distinct heel contact).  This same atypical motion occurs at heel lift where the entire foot is raised off the ground (as opposed to a distinct push off by the hallux). This gait pattern, often described as a functional flatfooted gait, is frequently observed in the PreClinical Clubfoot Deformity (PMSv greater than 15mm).

Differential Diagnosis

Rothbarts Foot

  • ​Knee Bend Test facilitates the differential diagnosis between these two embryological foot structures
  • Primus Metatarsus Supinatus values typically lower than 12mm
  • Treadmill Analysis

Mild Clubfoot Deformity​

Marfan Syndrome - incidence 1 in 5000 (see Photo below)

​​Knees Straight

  • Rothbarts Foot - Calcaneus perpendicular to ground
  • PreClinical Clubfoot Deformity - Calcaneus inverted (pronated)

Knees Bent

  • Rothbarts Foot - Calcaneus inverted (pronated)
  • PreClinical Clubfoot Deformity - Calcaneus inversion increases

Measuring the PreClinical Clubfoot Deformity  (Cummings GS, Higbie EJ 1997)

Differential Diagnosis - Rothbarts Foot vs PreClinical Clubfoot Deformity

Knee Bend Test

Functional Flatfooted Gait Associated with a Preclinical Clubfoot Deformity: foot motion is driven by Gravity Drive  observed from heel contact to heel lift