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Publication numberUS3785368 A
Publication typeGrant
Publication dateJan 15, 1974
Filing dateAug 23, 1971
Priority dateAug 23, 1971
Publication numberUS 3785368 A, US 3785368A, US-A-3785368, US3785368 A, US3785368A
InventorsLumb D, Mc Carthy T
Original AssigneeLumb D, Mc Carthy T
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Abnormal nerve pressure locus detector and method
US 3785368 A
Abstract
A system, device and method for readily detecting the locus of a subluxated or pinched nerve along the spinal column and particularly for identifying which particular pair of vertebrae are pressing upon a pinched nerve has been disclosed so that a medical person can relieve the pressure as by adjusting alignment of one of the pair of vertebrae. A T-shaped scanning probe is employed to explore along the regions directly over and also flanking the spinal column while another probe is held tightly in the patient's hand whereby a low voltage circuit can be provided which develops fluctuations in a meter reading the current or voltage through the circuit as the T-shaped probe is drawn along the back of the patient. A method for detecting nerve root pressure subluxations of the body of a patient in the regions of the spinal column in a manner which identifies the locus of the subluxation comprises a number of manipulative steps characterized by drawing the cross-piece of the probe along the back of the patient while directing the current in the circuit to emerge from the back of the patient into the T-shaped probe.
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States McCarthy et a1.

[ 1 Jan. 15, 1974 [76] Inventors: Thomas M. McCarthy, 940 Linden Dr., No. 130, Sunnyvale, Calif. 94087; Dale R. Luml), 1054 Bluebird Ave., Santa Clara, Calif. 95051 [22] Filed: Aug. 23, 1971 [21] Appl. No.: 173,935

[52] U.S. Cl. l28/2.1 Z, 128/2 N [51] Int. Cl ..A61b 5/05 [58] Field of Search 128/2 A, 2 H, 2 N, 128/2 R, 2.1 E, 2.1 R, 2.1 Z

[56] References Cited UNITED STATES PATENTS 2,669,986 2/1954 Crawley l28/2.l R

1,610,271 12/1926 Evins 128/2 H 3.306282 2/1967 Pierce 128/2 H 2,535,249 12/1950 Wilhelm et a1 128/21 Z 3,605,722 9/1971 Riseman et al. 128/2.1 R

Primary Examiner-William E. Kamm AlmrneyFlehr, Hohbach, Test, Albritton & Herbert [S 7] ABSTRACT A system, device and method for readily detecting the locus of a subluxated or pinched nerve along the spinal column and particularly for identifying which particular pair of vertebrae are pressing upon a pinched nerve has been disclosed so that a medical person can relieve the pressure as by adjusting alignment of one of the pair of vertebrae. A T-shaped scanning probe is employed to explore along the regions directly over and also flanking the spinal column while another probe is held tightly in the patients hand whereby a low voltage circuit can be provided which develops fluctuations in a meter reading the current or voltage through the circuit as the T-shaped probe is drawn along the back of the patient. A method for detecting nerve root pressure subluxations of the body of a patient in the regions of the spinal column in a manner which identifies the locus of the subluxation comprises a number of manipulative steps characterized by drawing the cross-piece of the probe along the back of the patient while directing the current in the circuit to emerge from the back of the patient into the T-shaped probe.

5 Claims, 4 Drawing Figures PATENTED 1 5 4 INVENTOR, TH AS M. MCCARTHY DA R. LUMB BY mz max, @J;

W ZX W ATTORNEYS ABNORMAL NERVE PRESSURE LOCUS DETECTOR AND METHOD BACKGROUND OF THE INVENTION This invention relates to a scanning system, device and method for readily detecting the locus of a subluxated or pinched nerve along the spinal column and more particularly for identifying which particular pair of vertebrae are pressing upon a pinched nerve so that a medical person can relieve the pressure as by adjusting alignment of one of the pair of vertebrae.

In the spinal column, nerves extend outwardly between confronting parts of adjacent pairs of vertebrae whereby, if one vertebra become cocked at an angle relative to the other, a nerve can become pinched. Pressure on the nerve in this manner can cause the nerve to become hyperactive whereby it develops more than its usual number of excitations or pulses. If the pressure becomes great enough, the nerve then may become hypoactive whereby its function is substantially diminished and the nerve becomes essentially deadened to a greater or lesser degree. It is not always readily evident as to which pair of vertebrae may be causing the nerve to be pinched, however.

It has been observed that sweat gland activity is generally affected by the nerves. Thus, where a nerve is hyperactive, there will be an excessively active sweat gland associated with that nerve. Conversely, hypoactive nerves tend to diminish the activity for their related sweat glands.

SUMMARY OF THE INVENTION AND OBJECTS As disclosed herein, a method and means are provided for not only locating the sweat glands which have been affected by nerve pressure, but also for locating those sweat glands which indicate the particular pair of vertebrae which are causing the nerve pressure so that the pressure can be relieved by treatment.

Thus, in general, a vertebral subluxation locus detector system has been provided characterized by an elongated electrode element having a predetermined polarity and adapted to be pressed against and wiped substantially in line contact with the skin of a patient along a path flanking the patients spinal column. The electrode element is formed with a length serving to contact and span the average distance between the sympathetic ganglionic chain of nerves of the spinal column and the midline of the spinal column. Another electrode is adapted to be held in the hand of the patient so as to form an electrical path via the patient between the first and second electrodes. Further, means for detecting impedance changes in the electrical path while wiping the first named electrode along the spinal path indicates changes in sweat gland avtivity of the patient along the first named path which sweat gland activity is directly related to the subluxation regions. Preferably, the polarities are such as to provide current flow from the hand held electrode via the body of the patient and to the exploratory electrode noted above. Further, the exploratory electrode or scanning electrode is comprised of a T-shaped member wherein the cross-piece thereof has an arcuate outer surface for engaging the skin of a patient along a line contact notwithstanding varying angular orientations of the stem portion of the T-shaped electrode.

A method for detecting nerve root pressure subluxations of the body of a patient in the regions flanking the spinal column in a manner identifying the locus of the subluxation comprises the steps as disclosed further below.

In general, it is an object of the present invention to provide an improved method and means for identifying the locus of a vertebral subluxation or pinched nerve region whereby the particular pair of vertebrae causing the pinching of the nerve can be treated.

It is a further object of the invention to provide a method and means for so identifying the locus of a vertebral subluxation using relatively simple techniques with minimum discomfiture to the patient.

The foregoing and other objects of the invention will become more readily evident from the following detailed description of a preferred embodiment when considered in conjunction with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic circuit diagram of a system according to the invention;

FIG. 2 is a diagrammatic representation of the back of a patient being examined pursuant to the method disclosed herein;

FIG. 3 is a graph showing comparative meter readings at 3.0 volts potential as between cathodal (C) and anodal (A) currents;

FIG; 4 is a graph similar to FIG. 3 at 4.0 volts potential on power supply 16.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT A vertebral subluxation locus detecting system 10 comprises an elongated electrode 11, preferably of nickel plated brass, adapted to be held in the fist 12 of a patient in order to minimize unwanted voltage drops in the interface defined between electrode 11 and the skin of the palm of the hand of the patient holding electrode 11. Thus, the probe contact area is relatively large and the contact location in the palm of the hand provides a maximum natural low impedance electrolyte in the form of perspiration from the sweat glands in the hand. Thus, the palm of the hand has a much higher density of sweat glands than on the arms or back, for example, and these glands are usually active under most conditions.

Electrode 11 is connected, as by means of lead 14, to the positive side of a variable voltage source 16 whereby electrode 11 has the characteristics of an anode and a T-shaped exploratory probe 13 forms a second electrode having the characteristics of a cathode connected, via an ammeter or other suitable meter 17 such as a voltage measuring means, to the negative side of the D.C. power supply 16.

It has been observed that a prolonged voltage applied across the skin eventually causes a decline in the probe/skin interface resistance so as to make it difficult to identify regions of hyperactive or hypoactive sweat gland activity on the skin by reading the skins resistance. Thus, the exploratory probe herein is a movable one and has a cylindrical elongated rod-shaped contact portion or element 18 having a length serving to contact and span the average distance between the sympathetic ganglionic chain of nerves of the spinal column and the midline 19 of the spinal column so as to define a path 21. It has been observed that by making the examination along path 21 as described herein, the responses obtained (indicative of nerve root pressure) will occur at locations along the path having a direct lateral relationship or displacement from the offending pair of vertebrae which are causing the detected nerve root pressure.

Thus, for most purposes, the rod-shaped element 18 of probe 13 extends approximately 32mm in length and has a diameter on the order of 4mm with rounded ends. The arcuate outer surface of element 18 provides line contact with the skin as it is wiped along path 21 flanking the centerline of the spinal column 19. The line contact provided by element 18 will exist notwithstanding varying angular orientations of the insulated stem portion 22 of probe 13. Preferably, element 18 is, of course, cylindrical in order to readily maintain such line contact as above described.

The above diameter must be small enough to provide relatively precise discrimination in detecting sweat gland activity since the resistance at the interface between element 18 and the skin of the patient is approximately inversely proportional to the contact area between the probe and the skin, the larger the exploratory probe, the smaller will be the difference in resistances as measured between the subluxation regions and normal regions. Accordingly, the probe would then, if larger, be less likely to detect a subluxation. Since the typical subluxation region is commonly circular and 2 to mm in diameter, the probe diameter of 4mm provides a relatively precise detection of the subluxation.

The tips of element 18 may be used in exploratory fashion in order to locate the precise sweat gland activity, if desired.

An electrical path 23 is formed via the patient 25 between the first and second electrodes 11, 13 and this path is indicated in dotted lines with a number of separate resistances indicated representative of the double layer resistances 24, 29 providing the major amount of resistance in path 23, the hand skin resistance 26, bulk tissue resistance 27, and back skin resistance 28.

It has been observed that, by causing the current flow in the circuit shown to move in the direction indicated by the lower case letters i, greater definition, particularly on moist skin, can be achieved since the interface resistance appears to be more stable when the steady current is outwardly moving toward exploratory probe 13.

Further, as shown in FIGS. 3 and 4, vertebral subluxation areas with anodal (A) and cathodal (C) currents at probe 13 are shown. The term anodal is used herein as representing the condition wherein current in the system shown in FIG. 1 moves in a direction opposite to the direction shown by the is therein. A cathodal current represents a current flowing in the direction shown in FIG. 1.

By a comparison of FIGS. 3 and 4, the inability to distinguish the subluxation area when using anodal current for probe 13 is readily apparent. Further, increasing the application potential fails to materially change the sensitivity of the detection method.

For a subluxation causing localized hyperactivity of the sweat glands, the distinguishability between normal and subluxation area measurement readings on meter 17 is, in part, due to the large difference in electrolyte provided at the skin/probe l3 interface where the subluxation area reduces this component of resistance 29 in the measurement circuit. If an A.C. potential is applied for a similar type of detection measurement, the skin/probe resistance is less than the corresponding DC. resistance in the normal skin areas. However, the subluxation area interface resistance decreases at much smaller proportions for an applied A.C. potential. Although the direction of potential can be reversed as in the DC. case to take advantage of the cathodal current characteristic, the difference in resistance between the two directions is much less. Thus, the DC. measurement technique has been observed to be much superior to an equivalent A.C. technique.

In operation, when it is desired to examine a patient to determine the locus of a vertebral subluxation or pinched nerve, the method for detecting the locus of nerve root pressure subluxations of the body is pursued in the regions flanking the spinal column in a manner comprising the steps of: cleaning those surface areas of a patients back flanking the spinal column so as to remove dirt, dead skin and contaminants if necessary. The skin is then dried along these surface areas and permitted to adjust to room temperature. Electrode 11 is disposed tightly held in the patient's hand and an electric potential is applied to electrode 11. The next step is to press a second electrode, such as the T- shaped probe 13, with moderate pressure against the skin in the surface areas such as 21 spanning the average distance between the sympathetic ganglionic chain of nerves of the spinal column and the midline of the spinal column to form a portion of an electrical circuit via the body of the patient between the first electrode 11 and a second electrode, such as probe 13. The second electrode 13 is formed with an elongated rod-like skin-engaging portion 18 of predetermined length and having an arcuate outer surface for contacting the skin, the radius of which lies in a range to make substantially a line contact with the skin of a width of the order of the sweat gland pores. The next step is to orient that portion 18 of probe 13 to extend laterally of the spinal column followed by drawing probe 13 along surface areas 21 in line contact therewith while measuring electrical resistance in circuit portion 23 to detect, as by means of meter 17, any abrupt substantial change therein, and marking the skin at the locus (e.g., 30) of such resistance changes so as to identify the related pair of vertebrae causing nerve root pressure.

Thus, it has been observed that the marked locii on the skin representing nerve root pressure detected in the foregoing manner typically lie laterally adjacent the confronting misaligned pair of vertebrae causing the nerve root pressure detected and marked by the above technique and apparatus.

From the foregoing, it will be readily evident that there has been provided an improved device, system and method of identifying the locus of a given pair of vertebrae causing nerve root pressure so that treatment can be readily effected.

We claim:

1. A system for detecting abnormal nerve pressure along the spinal column characterized by a DC. power supply having means for supplying both a positive and negative D.C. polarity, an elongated electrode element coupled to said means to be conditioned to a predetermined one of said polarities and adapted to be pressed against and wiped substantially in line contact with the skin ofa patient along a path adjacent and flanking the patients spinal column, the electrode element being adapted to contact the patient's back and span the average distance between the sympathetic ganglionic chain of nerves of the spinal column and the midline of the spinal column and having an arcuate outer peripheral surface means for providing a line contact with said skin, another electrode adapted to be held in the hand of the patient and coupled to the first said means to have a D.C. polarity opposite said predetermined polarity for forming an electrical path via the patient between the first and second named electrodes, and means for detecting impedance changes in said electrical path while wiping the first named electrode along the first named path for indicating changes in specific sweat gland activity of the patient along said first named path.

2. A system according to claim 1 further including means serving to establish said polarites to provide D.C. current flow from the hand-held electrode via the body of the patient and from the body to the first named electrode.

3. A system according to claim 1 wherein the first named electrode comprises a T-shaped member having a stem portion and wherein said element comprises the cross-piece of the T-shaped member, said cross-piece being adapted for engaging the skin of a patient, said cross-piece forming a line contact with said skin notwithstanding varying angular orientations of the stem portion of the T-member, said cross-piece having a length of the order of 32mm and an arcuate outer surface portion formed from a cylinder having a diameter of the order of 4mm.

4. A method for detecting nerve pressure in the body of a patient in the region ofthe spinal column in a manner identifying the vertebral level at which abnormal nerve pressure exists in the patient comprising the steps of disposing an electrode tightly held in the patient's hand, applying a D.C. electric potential to said electrode, applying a D.C. potential of opposite polarity to and pressing a second electrode with moderate pressure against the skin in said surface areas to form a portion of an electrical circuit via the body of the patient between the first named electrode and said second electrode, said second electrode having an elongated rod-like skin-engaging portion of predetermined length and an arcuate outer surface for contacting the skin, the radius of said arcuate surface lying in a range to make a line contact with the skin of a width of the order of the specific sweat gland pores of the skin, orienting said portion of said second electrode to extend laterally of the spinal column, drawing said second electrode along said surface areas while measuring the electrical resistance in said circuit portion to detect abrupt substantial changes therein, and marking the skin at the locus of such resistance changes to identify the vertebral level at which the indicated nerve pressure exists.

5. A method for detecting the vertebral level at which abnormal nerve pressure exists in the body of a patient according to Claim 4 wherein the current flow in said circuit portion is oriented to pass from the hand-held electrode to said second electrode via the patients body for completing an electric path leading out of the patients body via said skin surfaces directly over or flanking the spinal column.

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Classifications
U.S. Classification600/384
International ClassificationA61B5/05
Cooperative ClassificationA61B5/05
European ClassificationA61B5/05