Plantar reflex gauge and method of assessing a plantar reflex

Abstract

A plantar reflex gauge and method of assessing a plantar reflex of a subject in which a more standardized, graded approach can improve outcomes. The plantar reflex gauge can include a plurality of appendages, with each appendage of the plurality of appendages being connected via a connection area at a proximal end of each appendage. A plurality of prongs are located at the distal end of one or more appendages of the plurality of appendages. The method includes stroking a foot of the subject using a plantar reflex gauge, and grading a response of the subject using a reflex response scale. A grade assigned during the grading step includes a quantitative assessment along the reflex response scale.

Description

PLANTAR REFLEX GAUGE ANDMETHOD OF ASSESSING A PLANTAR REFLEXTECHNICAL FIELD

[0001] This disclosure is related to tools and methods for assessing the plantar reflex of a subject.BACKGROUND

[0002] In the late 1800s, in an address of merely 28 lines, Joseph Babinski presented plantar reflex before the Biological Society of Paris as a way to differentiate weaknesses of structural origin from the functional. Later, a variety of alternative methods of stimulation (Chaddock, Oppenheim, etc.) ensued to elicit an upgoing great toe as a sign of upper motor neuron pathology.

[0003] Despite its simple nature, elicitation and interpretation of the reflex have been fraught with controversy, to the point that even abandoning this practice has been advised — in spite of strong objections and perhaps even resentments.

[0004] One major hurdle in performing and interpreting the reflex in a standard way is probably its "all or nothing" description of a phenomenon, which in fact could have a "spectrum," with shades of intensity. Currently, there is absolutism inherent in the way it is practiced: positive / negative, with no shades of gradation.

[0005] The “plantar reflex,” “Babinski,” or “Babinski reflex,” as used herein, is the phenomenon of release of a primitive reflex consisting of extensor hallucis longus activation, simultaneous or subsequent to proximal tensor fasciae latae (TFL) muscular contraction, that emerges by weakening of corticospinal inhibition on lumbar motor pool, replacing the normal local skin reflex (plantar flexion) in response to stimulation of the sole. The proximal muscular contraction has been offered as a way of differentiation from voluntary withdrawal or tickle reaction, and in the rare case of a mute toe can stand as the hint to a subtle Babinski (e.g., in Landau & Clare’s series, TFL contraction in normal subjects was always preceded by a downgoing toe). The afferent limb of the reflex is mediated by A-Delta and C-fibers, and the efferent limb by myelinated motor nerves.SUMMARY

[0006] In accordance with one embodiment, there is provided a plantar reflex gauge comprising a plurality of appendages and a plurality of prongs. Each appendage of the plurality of appendages has a distal end and a proximal end. Each appendage of the plurality of appendages are connected via a connection area at the proximal end of each appendage, and each prong of the plurality of prongs is located at the distal end of one or more appendages of the plurality of appendages.

[0007] In some embodiments, each appendage comprises a different number of prongs than each other appendage of the plurality of appendages.

[0008] In some embodiments, the plurality of appendages comprises a first appendage, a second appendage, a third appendage, and a fourth appendage, and the first appendage has the most prongs and the fourth appendage has the least prongs.

[0009] In some embodiments, each appendage of the plurality of appendages has a length defined as a distance from the proximal end of each appendage to the distal end of each appendage, and wherein the length of each appendage of the plurality of appendages is the same.

[0010] In some embodiments, each prong of the plurality of prongs has a prong body extending from a first end to a second end, wherein the first end is connected to a head portion of each appendage of the plurality of appendages and a pointed tip extends from the second end. At least some prongs of the plurality of prongs can be distributed on one or more head portions in an equidistant horizontal prong array. Each pointed tip of each prong of the plurality of prongs can have a consistent sharpness.

[0011] In some embodiments, each appendage of the plurality of appendages is rotatably connected to one another via the connection area.

[0012] In some embodiments, there is a clip having a first end connected to the connection area and a second end configured to open and close, with the second end of the clip beingconfigured to at least partially rest on an appendage of the plurality of appendages in the closed position.

[0013] In some embodiments, each appendage of the plurality of appendages radiates outward from the connection area. Each appendage of the plurality of appendages can be spaced 90 degrees from each adjacent appendage of the plurality of appendages in a cross-formation.

[0014] sin some embodiments, the connection area comprises non-orthogonally angled junction edges between each appendage of the plurality of appendages.

[0015] In accordance with another embodiment, there is provided a method of assessing a plantar reflex of a subject. The method comprises stroking a foot of the subject using a plantar reflex gauge, and grading a response of the subject using a reflex response scale. A grade assigned during the grading step includes a quantitative assessment along the reflex response scale.

[0016] In some embodiments, the grade includes a positive or negative indication, wherein the positive indication represents an upward movement of a toe of the subject and the negative indication represents a downward movement of the toe of the subject.

[0017] In some embodiments, the quantitative assessment includes assigning a numerical value. The numerical value can correlate to a number of prongs on the plantar reflex gauge that cause the toe of the subject to move. The grade can include assigning a positive or negative indication to the numerical value.

[0018] In some embodiments, the plantar reflex gauge has a plurality of appendages, wherein the foot is stroked during the stroking step with a first multi-prong appendage of the plurality of appendages. A second stroking step can be included, wherein during the second stroking step, the foot of the subject is stroked with a second muti -prong appendage of the plurality of appendages, with the second multi-prong appendage having less prongs than the first multi-prong appendage. A subsequent stroking step after the second stroking step can be included, wherein the subsequent stroking step is accomplished using an appendage of the plurality of appendages, with the appendage ofthe plurality of appendages having less prongs than either of the first and second multiprong appendages.

[0019] It is contemplated that any of the above-listed features can be combined with any other feature or features of the above-described embodiments or the features described below and / or depicted in the drawings, except where there is an incompatibility of features.BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Illustrative embodiments will hereinafter be described in conjunction with the following figures, wherein like numerals denote like elements, and wherein:

[0021] FIG. 1 is a top view of a plantar reflex gauge in accordance with one embodiment;

[0022] FIG. 2 is a perspective view of another embodiment of a plantar reflex gauge; and

[0023] FIG. 3 shows an example plantar reflex response scale with a schematic representation of a method of assessing the plantar reflex response of a subject.DESCRIPTION OF EMBODIMENTS

[0024] Described herein is a tool and methodology that can be used to assess the Babinski sign or reflex (also known as the extensor plantar reflex). As opposed to using a finger or more simple tool to assess the reflex, the present tool and methodology allows for a more standardized and graded approach to assessment, which has the potential to improve clinical outcomes. Instead of a simple positive / negative indication, the present tooling and methods allow for a more specified assessment of the reflex, which can potentially be used by a clinician in a more nuanced characterization of an underlying neurological issue. Additionally, improvements are made to the tool to help accommodate manufacturing efficiencies, as well as usability and portability, particularly when employed in a clinical setting.

[0025] As used herein, the term "subject" is intended to include human and non-human animals. The terms "subject" and "patient" are used interchangeably and can refer to human patients, as well as non-human primates or experimental animals such as rabbits,dogs, cats, rats, mice, and other animals. Preferred subjects of the present disclosure include mammals, or more particularly, human patients such as newborns or babies that are being clinically assessed. Subj ects that are past two years old that present the Babinski sign may have damage to their central nervous system, but it should be understood that the device and methods described herein can be used in subjects and patients of any age.

[0026] FIG. 1 illustrates one embodiment of a plantar reflex gauge 100. The plantar reflex gauge 100 is comprised of a plurality of appendages, which in this embodiment, includes a first appendage 102, a second appendage 104, and third appendage 106, and a fourth appendage 108. As opposed to single appendage tooling that is typically used for the reflex assessment, the gauge 100 has more than one appendage 102, 104, 106, 108 that can be used to provide a more graded approach to reflex assessment. In some embodiments, there may be two appendages, or there may be more than four appendages, to cite a few alternative examples. The inclusion of four appendages 102, 104, 106, 108 helps better correlate the assessment to a reflex response scale, which is detailed further below. Additionally, this arrangement provides for enhanced structural variability amongst the different appendages 102, 104, 106, 108, while maintaining an easier to manufacture structure that can be efficiently carried by a clinician.

[0027] The appendage 102 is discussed herein with more structural detail, but it should be understood that teachings relating to the appendage 102 are applicable to the other appendages 104, 106, 108, with the exception of an incompatibility of features (e.g., the varying number of prongs for reflex assessment). Accordingly, relevant subcomponents of the appendage 102 are also applicable to the other appendages 104, 106, 108. Additionally, teachings relating to the plantar reflex gauge 100 are applicable to the other embodiments 200, 300 and vice versa, unless there is an incompatibility of features.

[0028] The appendage 102 includes a distal end 110 and a proximal end 112. The distal end 110 is generally the end used for reflex assessment, and the proximal end 112 of each appendage, in this embodiment, is connected at a connection area 114 to each other appendage 104, 106, 108. The distal end 110 of the appendage 102 includes a plurality of prongs 116. The distal end of the appendage 104 includes a plurality of prongs 118. The distal end of the appendage 106 includes a plurality of prongs 120, and the distal end of the appendage 108 includes a single prong 122. Locating something “at” the distal orproximal end 110, 112 generally means locating the subcomponent closer to that end than to the other opposing end, but in the illustrated embodiment, the prongs 118 are located directly at and projecting from the distal end 110. In some embodiments, it may be feasible to have one or more prongs that project from a side surface of the appendage, closer to the midpoint between the distal and proximal ends 110, 112, for example.

[0029] To enhance portability and manufacturability of the gauge 100, each appendage 102, 104, 106, 108 is configured to have the same length LA and thickness T (see thickness designation in the perspective view in FIG. 2). Additionally, the prong length Lp is consistent amongst all of the prongs 116, 118, 120, 122. This consistency can present a more uniform assessment region at the distal end 110. However, it is possible in some embodiments to vary the length LA, LP and / or thickness T depending on the desired testing features. For example, variable length prongs may be included instead of presenting a horizontally distributed array of similar length prongs along the width of the appendage. In the illustrated embodiment, the first multi-prong appendage 102 has a horizontal array spanning a width Wi that is larger than a width W2 of each appendage 102, 104, 106, 108. The second multi-prong appendage 104 has a consistent width W2, but the first multi -prong appendage 102 has an expansion portion 124 to accommodate a greater number of prongs 116 (six in this implementation, whereas arrangements with four or fewer prongs can be accomplished with distribution along the appendage width W2).

[0030] To provide variable testing capabilities, each appendage 102, 104, 106, 108 can be configured to radiate outwardly from the connection area 114. In the arrangement illustrated in FIG. 1, each appendage 102, 104, 106, 108 is spaced at a 90° angle with respect to adjacent appendages in a cross-formation 126. This configuration utilizes the available space around the connection area 114 to distribute the appendages 102, 104, 106, 108 so they can be more easily and intuitively deployed in a testing scenario. In this particular embodiment, non-orthogonally angled junction edges 128 are located at the corners between adjacent appendages 102, 104, 106, 108. These edges 128 can be easier to manufacture when using a molding process for the gauge 100, to cite one potential advantage.

[0031] In the FIG. 1 embodiment, the connection area 114 between each of the appendages 102, 104, 106, 108 is a rigid, integral, direct connection such that the plantar reflex gauge 100 is a unitary or monolithic piece. This area 114 can also help with maintaining a desirable prong distribution around the tool so that assessment can be effectively, yet efficiently performed. In the embodiment of FIG. 2, the connection area 214 includes a pivoting hinge 230 that directly connects each appendage 202, 204, 206, 208 at the proximal end 212 (like numerals denote like components and subcomponents). The pivoting hinge 230 can be used to rotatably connect each appendage 202, 204, 206, 208 at the connection area 214 to one or more adjacent appendages. This arrangement can be a bit more difficult to manufacture, but it can be more portable for a practitioner in a clinical setting. Additionally, with the pivoting hinge 230, it is still feasible to achieve a cross-formation when the appendages are radiated outwardly from the connection area 214. Other forms for the connection area 114, 214 are certainly possible, but having the direct coupling or connection at the connection area 114, 214 can advantageously enhance distal end 110, 210 accessibility of the appendages.

[0032] Returning more particularly to FIG. 1, but applicable to the FIG. 2 embodiment 200 as well, the distal end 110 of each appendage 102, 104, 106, 108 includes a head portion 132. The first multi-prong appendage 102 has a plurality of prongs 116 (with six, the highest number of prongs in this embodiment) that span an entire width Wi of the expansion portion 124 so as to be distributed in an equidistant horizontal prong array 134. The second multi-prong appendage 104 has a plurality of prongs 118 (with four prongs) that span an entire width W2 of the appendage so as to also be distributed in an equidistant horizontal prong array 134. The third multi -prong appendage 106 has two prongs in the plurality of prongs 120. The prongs 120 are distributed on the head portion 132, but the spacing between the prongs is consistent with the spacing in the horizontal prong array 134. This spacing can help correlate reflex responses with the reflex response scale, detailed further herein. Additionally, the equidistant horizontal prong array 134 can help control a desired amount of bluntness / sharpness variability to promote a more graded reflex response.

[0033] The prong 122 will be discussed herein as an example prong that may be applicable to the other prongs in the plurality of prongs 116, 118, 120. In the embodiment of FIG.1, all of the prongs 116, 118, 120, 122 have consistent dimensions, which can improveease of manufacturability. However, it is possible to have one or more variably structured prongs emanating from one or more of the appendages 102, 104, 106, 108. Additionally, it may be feasible to include prongs in different sizes or configurations than those particularly illustrated herein.

[0034] The prong 122 has a prong body 136 extending from a first end 138 to a second end 140. The first end 138 of the prong body 136 is directly connected to the head portion 132 of the appendage 108. The second end 140 of the prong body 136 includes a pointed tip 142. The pointed tip 142 is the reaction surface for the gauge 100. In the embodiment illustrated in FIG. 1, each of the pointed tips 142 on each prong of the plurality of prongs 116, 118, 120 has the same sharpness. Additionally, the pointed tip 142 on the prong 122 has the same sharpness as each of the pointed tips 142 on each prong of the plurality of prongs 116, 118, 120. Having the same sharpness can provide somewhat of an experimental control, as the variability focuses on the number of prongs on each appendage 102, 104, 106, 108.

[0035] Dimensionally, the prong body 136 has a thickness T that is consistent with each respective appendage 108. This can be easier to manufacture, but it is feasible to have alternately dimensioned prong bodies 136. In the embodiment of FIG. 1, the prong body 136 is consistently squared until the pointed tip 142. Each pointed tip 142 in this particular embodiment has a pyramidal taper 144, but it is possible to have other configurations, such as a conical taper. In the embodiment of FIG. 2, the appendage 204 includes example pointed tips having a dual sided taper 246 that forms more of a slotted, wedged-shaped tip. This option may provide a blunter reaction surface. It is technically feasible to have all similarly configured pointed tips 142, 242, or have some structural variability to alter the reaction surface of the gauge 100, 200.

[0036] Other features can be included to enhance operability and portability of the plantar reflex gauge 100, 200. For example, as shown in FIG. 2, the gauge 200 includes a clip 250 that can allow for efficient transport in a clinical setting, for example. The clip 250 has a first end 252 that is connected at the connection area 214 and a second end 254 that is configured to open and close. More particularly, this implementation has the clip 250 rotatably connected via the pivoting hinge 230 to help provide a more compact arrangement for the gauge 200. Additionally, the clip 250 is configured so that the secondend 254 rests on the appendage 202 when in the closed position. Other clip forms and / or attachment mechanisms are certainly possible, along with other features, such as a cover or sheath, to cite one potential example.

[0037] With reference to FIG. 3, in some embodiments, the plantar reflex gauge 100, 200, 300 can be used in a clinical assessment of a subject’s plantar reflex. Varying intensities and shades of sharp / dull afferent stimulation can be used to grade the reflex positivity, potentially similar to subconsciously weighing of the intensity of hammer impact on a tendon while eliciting deep tendon reflexes. Using a tool that increases the sharpness intensity (e.g., plantar reflex gauge 100, 200, 300 or another operable gauge or tool), a subject’s response can be assessed on a reflex response scale 360. In this implementation, a reflex response scale 360 involves assigning a grade to the subject’s response, which involves a quantitative assessment of the response. This quantitative assessment may be a numerical value, as illustrated. In other implementations the quantitative assessment may include response ranges as opposed to static values, or it may be otherwise subdivided based on a quality along a scale, to cite a few examples.

[0038] In practice, while focusing on direction of movement of the great toe and contraction of tensor fasciae latae (TFL): starting with higher number of prongs (blunter, e.g., appendage 102), the reflex is positive if there is TFL contraction simultaneous to, or preceding the upward movement of the great toe. The numerical value is based on the maximum number of prongs moving the toe, and the positivity or negativity based on the direction of movement (positive: up away from sole; negative: down toward the sole; see arrows in FIG. 3). The bluntness of the gauge 100 is generally proportional to the number of prongs (e.g., more prongs is generally “blunter” whereas less prongs or a single prong is more likely to evoke a reaction). In positive cases, “B-scored” between + U and +4 for the quantitative assessment. The result is a smaller number of prongs needed to elicit the response, with sharper or more concentrated stimulation being required. This result may be correlated to a milder or lack of normal corticospinal inhibition of the reflex. A mute toe in presence of TFL contraction can be described as + U.

[0039] Accordingly, in practice with the gauge 100, the first multi-prong appendage 102 can be used to stroke the subject’s foot, followed by the second multi -prong appendage 104 that has fewer prongs, then followed by the third multi -prong appendage 106, andfinally the fourth appendage 108, which in this example, has a single prong 122. A downgoing toe (a local reflex) is considered negative, and intensity of negativity is proportionate in this embodiment to the maximum prongs eliciting the movement, expressed as a range for the quantitative assessment [B score ranging from 0 (mute toe with no TFL contraction) to -4],

[0040] A more measured and comparative way of reporting the phenomenon between different subjects and observers, the same method can even be attempted in the same subject, comparing the two sides. In some implementations, grades of positivity may be correlated with sizes of lesions, and the difference between the two legs (8-B) in search of a cut-off point of significance. A difference in negativity between the two sides — currently considered normal — may potentially be of clinical significance.

[0041] It is to be understood that the foregoing description is of one or more embodiments of the invention. The invention is not limited to the particular embodiment(s) disclosed herein, but rather is defined solely by the claims below. Furthermore, the statements contained in the foregoing description relate to the disclosed embodiment s) and are not to be construed as limitations on the scope of the invention or on the definition of terms used in the claims, except where a term or phrase is expressly defined above. Various other embodiments and various changes and modifications to the disclosed embodiment s) will become apparent to those skilled in the art.

[0042] As used in this specification and claims, the terms “e.g.,” “for example,” “for instance,” “such as,” and “like,” and the verbs “comprising,” “having,” “including,” and their other verb forms, when used in conjunction with a listing of one or more components or other items, are each to be construed as open-ended, meaning that the listing is not to be considered as excluding other, additional components or items. Other terms are to be construed using their broadest reasonable meaning unless they are used in a context that requires a different interpretation. In addition, the term “and / or” is to be construed as an inclusive OR. Therefore, for example, the phrase “A, B, and / or C” is to be interpreted as covering all the following: “A”; “B”; “C”; “A and B”; “A and C”; “B and C”; and “A, B, and C .”

Claims

CLAIMS1. A plantar reflex gauge, comprising:a plurality of appendages, wherein each appendage of the plurality of appendages has a distal end and a proximal end, wherein each appendage of the plurality of appendages are connected via a connection area at the proximal end of each appendage; anda plurality of prongs, wherein each prong of the plurality of prongs is located at the distal end of one or more appendages of the plurality of appendages.

2. The plantar reflex gauge of claim 1, wherein each appendage comprises a different number of prongs than each other appendage of the plurality of appendages.

3. The plantar reflex gauge of claim 1, wherein the plurality of appendages comprises a first appendage, a second appendage, a third appendage, and a fourth appendage, and wherein the first appendage has the most prongs and the fourth appendage has the least prongs.

4. The plantar reflex gauge of claim 1, wherein each appendage of the plurality of appendages has a length defined as a distance from the proximal end of each appendage to the distal end of each appendage, and wherein the length of each appendage of the plurality of appendages is the same.

5. The plantar reflex gauge of claim 1, wherein each prong of the plurality of prongs has a prong body extending from a first end to a second end, wherein the first end is connected to a head portion of each appendage of the plurality of appendages and a pointed tip extends from the second end.

6. The plantar reflex gauge of claim 5, wherein at least some prongs of the plurality of prongs are distributed on one or more head portions in an equidistant horizontal prong array.

7. The plantar reflex gauge of claim 5, wherein each pointed tip of each prong of the plurality of prongs has a consistent sharpness.

8. The plantar reflex gauge of claim 1, wherein each appendage of the plurality of appendages is rotatably connected to one another via the connection area.

9. The plantar reflex gauge of claim 1, further comprising a clip having a first end connected to the connection area and a second end configured to open and close, wherein the second end of the clip is configured to at least partially rest on an appendage of the plurality of appendages in the closed position.

10. The plantar reflex gauge of claim 1, wherein each appendage of the plurality of appendages radiates outward from the connection area.

11. The plantar reflex gauge of claim 10, wherein each appendage of the plurality of appendages is spaced 90 degrees from each adjacent appendage of the plurality of appendages in a cross-formation.

12. The plantar reflex gauge of claim 1, wherein the connection area comprises non-orthogonally angled junction edges between each appendage of the plurality of appendages.

13. A method of assessing a plantar reflex of a subject, the method comprising:stroking a foot of the subject using a plantar reflex gauge; andgrading a response of the subject using a reflex response scale, wherein a grade assigned during the grading step includes a quantitative assessment along the reflex response scale.

14. The method of claim 13, wherein the grade includes a positive or negative indication, wherein the positive indication represents an upward movement of a toe of the subject and the negative indication represents a downward movement of the toe of the subject.

15. The method of claim 13, wherein the quantitative assessment includes assigning a numerical value.

16. The method of claim 15, wherein the numerical value correlates to a number of prongs on the plantar reflex gauge that cause the toe of the subject to move.

17. The method of claim 15, wherein the grade includes assigning a positive or negative indication to the numerical value.

18. The method of claim 13, wherein the plantar reflex gauge has a plurality of appendages, wherein the foot is stroked during the stroking step with a first multi-prong appendage of the plurality of appendages.

19. The method of claim 18, comprising a second stroking step, wherein during the second stroking step, the foot of the subject is stroked with a second muti-prong appendage of the plurality of appendages, wherein the second multi-prong appendage has less prongs than the first multi-prong appendage.

20. The method of claim 19, comprising a subsequent stroking step after the second stroking step, wherein the subsequent stroking step is accomplished using an appendage of the plurality of appendages, wherein the appendage of the plurality of appendages has less prongs than either of the first and second multi-prong appendages.

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