Technical Field

Embodiments relate to a foot position assembly and, in particular, a foot positioning assembly used during scanning.

Background

Podiatrists study the stance and gait of a patient, as well as the biomechanics of the patient’s feet and lower limbs, with a view to addressing deviations. Since shoes and footwear in general are manufactured for the average feet, those people whose feet of formed differently may experience problems wearing such footwear. Other people may have feet formed in such a way that physiological problems arise over time unless addressed.

In suitable cases, a podiatrist will recommend that a patient use shoe inserts, custom soles or shoes(orthoses). In order to ensure that the orthoses fit correctly it is necessary to measure the patient’s feet. Such measurement of the patient’s feet can be carried out whilst the patient is standing (weight-bearing) or whilst the patient is sitting or lying down (non-weightbearing).

For non-weightbearing measurements of a patient’s foot, the traditional method has been to take a cast of the foot. However, there are a number of disadvantages to this casting process. Primarily, it is inconvenient, messy and time- consuming for the practitioner and the patient. In addition, there is a time delay involved in waiting for the cast to set. The cast then has to be transported to the manufacturing facility involving that additional delay and cost.

More recently, podiatrists have been employing a handheld scanning assembly which attaches to a portable computer such as a tablet and which provides a three-dimensional model of the foot. The model is then used to have the orthosis manufactured according to the practitioner’s specifications.

Generally, the function of a foot orthosis is to assist in pressure distribution and altering the kinetics and kinematics during the patient’s gait. Therefore, when taking a scan of the foot, it is desirable for the foot to be positioned in a manner which will achieve the required result of pressure reduction and appropriately altered kinetics and kinematics during the patient’s gait. During the traditional casting of the foot, a skilled and experienced practitioner would place the foot in the correct position. However, ensuring the correct position often relied on the experience of the practitioner and deviations in the resulting orthosis could result from small variations in the positioning of the foot.

It is not possible for the practitioner to position the foot manually during the scanning process if they are also holding the scanner. There has been a tendency to keep the foot in the resting position during scanning, resulting in less than optimal orthoses.

US 2012/0053490 A1 discloses an apparatus for determining the contours of a patient’s foot by using optical image scanning. The apparatus includes an alignment section for aligning the second metatarsal head with the distal one third of the lower leg to place the subtalar joint in a neutral position. The alignment section does so by engaging with the plantar surface of the foot substantially only in the immediate area of the fifth metatarsal head. The disclosed apparatus is only suitable for patients in a sitting position. Furthermore, although a neutral subtalar joint is desirable, this is not the only requirement for an accurate orthoses. Further disadvantages to the disclosed apparatus are that it does not replicate the

appropriate forefoot to rear foot relationship and that it requires a heel stirrup which interferes with the scanning process.

Summary of the Disclosure

An embodiment provides an assembly for positioning a foot of a patient during a scanning process, the assembly comprising:

a first foot engagement member for engaging with a dorsal surface of a medial forefoot of the foot of the patient; and

a second engagement member for engaging with a plantar surface of a lateral forefoot of the foot of the patient.

A force of the engagement of the first and second engagement members may be sufficient to encourage plantar flexion of a first ray of the foot.

A force of the engagement of the first and second engagement members may be sufficient to cause plantar flexion of a first ray of the foot. A force of engagement may be determined when the foot is in a relaxed position. The relaxed position of the foot may be a position of the foot when the patient is in a supine position or a prone position

The first and second engagement members may be moveable between first and second positions, wherein when the first and second engagement members are in the first position, the assembly engages with a left foot and when the first and second engagement members are in the second position, the assembly engages with a right foot. The assembly may engage with both the left and the right foot without relocating the assembly. Where the assembly includes a base, the assembly may engage with both the left and the right foot without moving the base. The assembly may have only first and second engagement members for engaging with a patient’s foot.

The assembly may have a first configuration for use with a supine patient and a second configuration for use with a prone patient. The first and second

engagement members may be moveable to accommodate the left or right foot of a patient. The first and second engagement members may additionally or alternatively be moveable to engage with the foot of the patient when the patient is in a supine position or in a prone position.

One of the first or second engagement members may include a moveable portion.

The moveable portion may include a flexible portion. The flexible portion may be resiliently flexible. The flexible portion may be resiliently flexible so that it can be moved into position and then retain that position during engagement with the patient’s foot.

The moveable portion may comprise a pivotable portion.

Both the first and second foot engagement members may comprise corresponding first and second moveable portions.

The assembly may further comprise a base.

The base may be planar for location under the patient’s leg or torso so that the weight of the patient secures the assembly in place. The assembly may comprise a strut connected to the base wherein the first and second engagement members are connected to the strut. The strut may be connected to the base at or near a side of the base.

The first and second engagement members may comprise corresponding flexible and pivotable portions.

The first engagement member may comprise a first pivotable member connected to the strut to allow pivoting movement of the first pivotable member relative to the strut and a first flexible member connected to the first pivotable member, and wherein

the second engagement member may comprise a second flexible member connected to the strut and a second pivotable member connected to the second flexible member to allow pivoting of the second pivotable member relative to the second flexible member.

The strut may be moveable relative to the base.

The strut may be pivotable relative to the strut.

At least a part of either the first or the second engagement member may be at least partially transparent. The pivotable member of the first foot engagement member may comprise a bar. The bar may be at least partially transparent.

The second pivotable member may comprise a bar. The second pivotable member may comprise a ball connected to the bar.

A further embodiment relates to a method of positioning a foot of a patient during a scanning process, the method comprising:

providing an assembly having first and second foot engagement members; engaging the first engagement member with a dorsal surface of a medial forefoot of the foot of the patient; and

engaging the second engagement member with a plantar surface of a lateral forefoot of the foot of the patient.

The method may further comprise scanning the foot whilst engaging the first and second engagement members with the foot.

The step of engaging the first engagement member with the foot may encourage plantar flexion of a first ray of the foot. The step of engaging the first engagement member with the foot may establish the forefoot to rear foot

relationship.

The first and second engagement members may be moveable between first and second positions, wherein when the first and second engagement members are in the first position, the assembly engages with a left foot and when the first and second engagement members are in the second position, the assembly engages with a right foot, the method comprising moving the first and second engagement members between the first and the second positions.

The first or second engagement members may include a moveable portion and wherein the method comprises moving the moveable portion to engage at least one of the first and second engagement members with the foot.

The step of moving the moveable portion may include one or more of translation; flexing and pivoting.

The first foot engagement member and the second foot engagement member may either or both rotate relative to the base. In an embodiment they independently of one another.

The assembly may further comprise a base in which case the method may comprise placing the base under the patient’s leg or torso so that the weight of the patient secures the assembly in place.

The method may comprise the step of establishing a subtalar joint is neutral by palpating a talar neck or visually aligning the rear foot to the leg.

The method may comprise positioning the second engagement member, preferably the pivotable member of the second member, so it sits on or distal to the 4 ^th and 5 ^th metatarsals (preferably the metatarsal heads) and is orientated in the direction of the sulcus. A portion of the second engagement member preferably does not extend further across the foot or point down towards the heel.

The method may further comprise encouraging plantar flexion of a first ray of the foot by using the first engagement member, preferably a moveable portion of the first engagement member, preferably the ball. This may be done by positioning the ball on a dorsal surface of a first metatarsal head and orientating the flexible portion so it is applying a force in a plantar direction. A further embodiment relates to an assembly for positioning the foot of a patient during a scanning process, comprising a first foot engagement member and a second foot engagement member wherein the first and second foot engagement members are positionable in first and second positions, wherein the respective first positions are for engagement with a left foot, and the respective second positions are for engagement with a right foot.

The first and second engagement members may be moveable between the first and second positions.

At least a part of the first or second engagement members may be at least partially transparent.

The assembly may have a first configuration for use with a supine patient and a second configuration for use with a prone patient. The first and second

engagement members may be moveable to accommodate the left or right foot of a patient. The first and second engagement members may additionally or alternatively be moveable to engage with the foot of the patient when the patient is a supine position or a prone position.

The assembly may encourage or cause plantar flexion of a first ray of the foot. This may increase the arch height in the non-weight bearing position when

compared to the rest position. In turn, this may increase the calcaneal-navicular pitch, decrease the forefoot varus or supinatus angle and increase the forefoot valgus angle. These changes may have significant advantages when prescribing orthoses or ankle-foot-orthoses including increased comfort and improved clinical results.

The ability to scan the entire foot, ankle and leg without anything impeding the view of the scanner allows for a more complete scan to more accurately prescribe orthoses or ankle-foot orthoses.

Certain embodiments may allow a patient to be either prone or supine and this may provide more versatility for scanning different types of patients, in particular those unable to, or preferring not to, assume one of these positions.

A further embodiment provides a assembly for positioning the foot of a patient during a scanning process, comprising a first foot engagement member and a second foot engagement member wherein assembly has a first configuration for use with a supine patient and a second configuration for use with a prone patient.

The assembly may be moved from the first configuration to the second configuration by flipping the assembly. The assembly may be flipped or rotated through 180°. Where the assembly includes a strut attached to a base, the strut may point upward in the first configuration and downward in the second

configuration.

Description of the Drawings

Embodiments are herein described, with reference to the accompanying drawings in which:

Figure 1 is an isometric view of a foot positioning assembly according to an embodiment;

Figures 2 to 4 are isometric views of the foot positioning assembly of Figure 1 engaging with respective right (Figures 2A, 3A and 4A) and left (Figures 2B, 3B and 4B) feet of a patient in a supine position; and

Figures 5 to 7 are isometric views of the foot positioning assembly of Figure 1 engaging with respective left (Figures 5A, 6A and 7 A) and right feet of a patient in a prone position (Figures 5B, 6B and 7B).

Detailed Description of Specific Embodiment

Figure 1 illustrates an assembly for positioning the foot of a patient during a scanning process 10. The assembly 10 comprises a base 12. The base 12 is formed as a planar member suitable for the occasion between the leg of a patient and a resting surface such as a bed.

Strut 14 is attached to the base 12 by pivoting joint 40 so that the strut 14 is able to rotate relative to the base 12. The assembly 10 further comprises a first, plantar engagement member 18 and a second, dorsal engagement member 30.

The plantar engagement member 18 comprises a flexible portion 20 which is attached a bar 22 by means of pivoting joint 24. In this embodiment, the bar 22 is made from acrylic so that it is semitransparent. This facilitates the scanning process since that material may transmit some or all of the radiation used by the scanner. It is to be realised that other materials may also be used. A material such as acrylic may have the additional advantage of being optically semi-transparent, facilitating accurate placement of the bar 22 by the practitioner.

The dorsal engagement member 30 comprises a flexible portion 32 and a bar 34. Ball 36 is mounted to the end of the bar 34 and the bar 34 is pivotally mounted to the flexible member 32 by means of pivoting joint 38.

The pivoting joints 24 and 38 are comprised of a thread located within respective flexible members 32 and 20 and a nut retaining the bar 22 and bar 34 in place while still allowing rotation of those parts relative to the respective flexible portions.

The flexible portions 20 and 32, in this embodiment, are resiliently flexible so that it may be moved into position by flexing and retains the intended position. In an embodiment, the flexible portions 20 and 32 are composed of gooseneck tubing.

In this embodiment, the strut 14 is comprised of a tube which can pivot relative to the base 12. As the strut 14 pivots relative to the base both the plantar engagement member 18 and the dorsal engagement member 30 are moved relative to the base 12.

Figures 2 to 7 illustrate the assembly 10 in use. In particular, Figures 2 to 4 illustrate the use with both left and right legs when a patient is in a supine position. Figures 2A, 3A and 4A illustrate the use with a right leg and Figures 2B, 3B and 4B illustrate the use with a left leg.

As illustrated in Figures 2A and 2B, the assembly 10 is positioned under the lower leg of a patient. The assembly is then manipulated using the pivoting joints 24, 38 and 40, as well as the flexible members 20 and 32 as follows.

1. The subtalar joint neutral is established by palpating the talar neck or visually aligning the rearfoot to the leg.

2. The bar 22 is positioned so it sits distal to or on the 4 ^th and 5 ^th metatarsal heads and is orientated in the direction of the sulcus. The bar 22 should not extend further across the foot or point down towards the heel.

3. Encourage plantar flexion of the first ray and reinstate the forefoot to rearfoot relationship of the foot by using the ball 36. This is done by positioning the ball 36 it on the dorsal surface of the first metatarsal head and orientating the flexible portion 32 so it is applying a force in a plantar direction.

Once the bar 22 and ball 36 are in position, the optimised medial and lateral longitudinal arch morphology may be improved resulting in a better orthosis fit.

Embodiments may resulting in optimised calcaneal pitch which may replicate the anatomical forefoot to rearfoot relationship and reduced forefoot supinatus with the first ray plantarflexed. In this position it is possible to scan up to the malleoli and beyond which may facilitate more effective orthoses with deep heel cups and flares or flanges.

Figures 5 to 7 illustrate use of the assembly 10 with a patient in a prone position. As illustrated, Figures 5A, 6A and 7A show the use with the patient’s left foot and Figures 5B, 6B and 7B show use with the patient’s right foot.

Both the plantar engagement member 18 and the dorsal engagement member 30 may be moved to engage with both the left and the right foot by movement of the strut 14, flexible portion 32 and pivoting joint 32 for the dorsal engagement member and movement of the strut 14, flexible portion 20 and pivoting joint 24 for the plantar engagement member 18. Therefore, the flexible portion 32 and pivoting joint 32 may be considered a moveable portion of the dorsal

engagement member 30 and the flexible portion 20 and pivoting joint 24 a moveable portion of the plantar engagement member 18.

As the strut 14 extends perpendicularly from the planar base 12 the assembly 10 may be used with a patient either in a prone or a supine position by flipping the assembly (i.e. rotating the assembly through 180°) and aligning the bar 22 and ball 36 appropriately using the other pivoting joints and the flexible members.

Furthermore, as illustrated, the pivoting joint 40 which attaches the plantar and dorsal engagement members to the base, is located substantially towards one side of the base. This allows the assembly to be used when the patient is in a prone position while lying on a bed, since the strut will then point downwards, and the off- centre location of the strut allows the base to act as an anchor and the two engagement members to engage with the foot which then extends downwards relative to the surface of the bed, as shown in Figures 5 to 7.

Although certain embodiments are used to position a patient’s foot during a scanning operation, it is to be realised that the assembly may have alternative or additional uses. For example, the assembly may be used during inspection by a practitioner, the construction of footwear; radiology; surgery or any other practice where inspection and positioning of the foot is important.

It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art in Australia or any other country.

In the claims which follow and in the preceding description, except where the context requires otherwise due to express language or necessary implication, the word“comprise” or variations such as“comprises” or“comprising” is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments.