AU2019101388A4 - A support and positioning stand for medical instruments - Google Patents

Abstract

There is a support frame 1 for positioning a medical instrument with respect to a patient. The frame in a position of use includes an upwardly extending post 4 rotatable on a support base 18 about an axis and a lateral arm of variable length 2 extending out from said post to support an attachment point 1A for said medical instrument. The post 4 and arm 2 are movable through respective horizontal and vertical arcs so that the position of said attachment point 1A can be selectively raised, lowered, pivoted about and displaced laterally of said axis. t I 2A r- - - 6 14., FIGUR E 1\ 10 - -

Description

This invention relates to medical equipment. More particularly, although not exclusively, it discloses a support frame for holding or positioning a medical instrument such as a TMS magnetic coil.

TMS coils are used to treat a range of abnormalities of the central nervous system. The treatment as described in more detail in prior art patent specifications EP2252367, involves positioning the coil at a position relative to a patient’s head to produce transcranial magnetic stimulation of a selected area of the brain. As the coil is heavy and must be held at a precise position for a significant time a support structure is necessary.

In the prior art TMS coils have been held in place on the patients head by the operator, researcher or doctor.

Mechanical arms, frames or cables suspended from a ceiling have also been used to support the said coils.

These mechanical arms, frames or cables are constructed with complex adjustment devices, which are difficult to use.

When setting up a coil position and patient for treatment, the optimal coil position is identified by the patients reaction to consecutive magnetic pulses applied to the patient’s motor cortex while the coil is moved in small increments through 5 axes relative to the patients skull until the optimal position is found. The position and orientation of the coil then needs to be fixed through five degrees of freedom( five axes). Typically the coil holders/stands currently available use only one or two clamping mechanisms to fix all 5 movements, and so the coil position through one

2019101388 12 Nov 2019 axis can be lost when adjusting the coil position in another axis. Also with the current coil stands/positioners the coil is fixed to a mechanical arm or arms which are pushed manually until the optimal treatment position is found. This includes moving the coil in increments as small as 1-2mm which can be difficult to achieve.

The coil and coil holder must also be held still while the locking mechanism is activated otherwise the optimal position can be compromised.

Because current coil holders/stands are difficult to manoeuver in small increments, the TMS coil is often removed from the coil holder/positioner and hand-held during the patient set up procedure. This requires the operator to hold a coil weighing up to 4 kilograms while leaning over and around a patient, which can lead to shoulder and back injuries. The risk of physical injury to the patient is also increased.

There are also prior art coil positioning systems available which use computer controlled movements of a robotic arm to move a coil to a desired position for treatment. However, these systems are expensive, and rely on data from an external source e.g., an MRI of the patients brain. The operation of these systems requires a high level of technical training which makes them logistically cumbersome and not easily initiated in a clinical situation.

Typical examples of support structures or frames currently known or in use are described in prior art patent specifications EP2252367, EP1708787 and US8088058. These use counterweights, springs and pulley systems to assist the operator with manual positioning of the coil. Manual locking is also required once the required position is found. The frames described in

2019101388 12 Nov 2019 the above documents tend to be imprecise and slow to prepare for a treatment.

It is therefore an object of this invention to ameliorate the aforementioned disadvantages and accordingly a support frame is disclosed for positioning a medical instrument with respect to a patient, said frame in a position of use including an upwardly extending post rotatable on a support base about an axis and a lateral arm of variable length extending out from said post to support an attachment point for said medical instrument and said post and arm being movable through respective horizontal and vertical arcs whereby the position of said attachment point can be selectively raised, lowered, pivoted about and displaced laterally of said axis.

Preferably said post and lateral arm are movable by means of electric linear actuators.

It is further preferred that said post and lateral arm are movable on pivot connections between said arm and post and bearings between said post and support base.

It is further preferred that said lateral arm of variable length includes a linear actuator.

Currently preferred embodiments of the invention will now be described with reference to the attached drawings in which:Figure 1 is a schematic side elevation view of a support frame according to the invention,

Figure 2 is a schematic plan view of the frame of figure 1, and

2019101388 12 Nov 2019

Figure 3 is a schematic side elevation view of the frame of figure 1.

Referring first to figure 1 a first embodiment of the support frame, shown generally as 1, has an outer attachment point 1A where a clamp is mounted to hold a TMS coil (not shown).

The attachment point 1A is fixed to one end of an arm 2 which in one orientation may be horizontal as shown. The arm 2 includes a linear actuator 2A which forms the other end of said arm and is attached via a pivot 3 to a vertical outer support post 4. Suitable linear actuators for this embodiment are available commercially from Motion Dynamics Australia Pty Ltd of Wetherill Park, NSW, 2164. In the configuration shown the actuator 2A can be made to extend or contract whereby the arm 2 moves the attached attachment point 1A horizontally relative to the post 4 at pivot 3.

A second upwardly inclined linear actuator 5 has one end attached at a pivot 6 to a fixed point on an upper support post 4. An opposite end of the linear actuator 5 is connected at a pivot 7 on the arm 2 intermediate the ends. The length of the linear actuator 5 can be made to extend or contract to raise or lower the outer attachment point 1A on the arm 2 through a predominately vertical arc 7A. This adjusts the height of the attachment point 1A.

A third linear actuator 11 is predominately horizontal with one end connected at pivot 12 to the end of strut 13 which is fixed at the other end to the lower support post 10. The opposite end of the linear actuator 11 is attached via a pivot 14 and bracket 15 to the upper support post 4. The upper support post 4 is mounted on bearings 8 and

2019101388 12 Nov 2019 so that it can rotate relative to a lower support post 10. The length of the linear actuator 11 can then be made to extend or contract to cause the upper support post 4 to rotate on lower support post 10 and thereby move the attachment point 1A around the longitudinal axis 15A of said lower post 10 through an arc 15B which is predominately horizontal.

The lower support post 10 is also mounted on bearings 16 and 17 so that it can rotate relative to a base post 18 and also move linearly relative to said base post. The height of the inner support post 10 can be adjusted relative to said base post 18 by a pin 19 located in any one of a plurality of holes 20. The pin 19 engages in one or two of a plurality of radial grooves 19A in an upper face of bearing 16 and maintains the rotary position of the inner support post 10 relative to the base post 18.

Push button 21 when depressed supplies electricity to the linear actuator 5 causing it to extend, moving the arm 2 upward through a predominately vertical arc thereby raising the attachment point 1A.

Push button 22 when depressed supplies electricity to linear actuator 5 causing it to contract to move the arm 2 downward through a predominately vertical arc thereby lowering the attachment point 1A.

Push button 23 when depressed supplies electricity to linear actuator 11 causing it to extend to move the arm 2 clockwise when viewed from above through a predominately horizontal arc thereby also moving the attachment point 1A clockwise when viewed from above through a predominately horizontal arc

Push button 24 when depressed supplies electricity to linear actuator 11

2019101388 12 Nov 2019 causing it to contract to move the arm 2 anticlockwise when viewed from above through a predominately horizontal arc thereby also moving the attachment point 1A anticlockwise when viewed from above through a predominately horizontal arc.

Push button 25 when depressed supplies electricity to actuator 2A causing it to extend the arm 2 thereby moving the attachment point 1A away from said pivot 3 through a predominately horizontal path when the frame is in the configuration shown.

Push button 26 when depressed supplies electricity to the actuator 2A causing it to contract the arm 2 thereby moving the attachment point 1A toward said pivot 3 through a predominately horizontal path when the frame is in the configuration shown.

Push button 27 when depressed in conjunction with any of pushbuttons 21, 22, 23, 24, 25, or 26 causes linear actuators 2A, 5 or 11 to expand or contract at an increased speed. Push button 27 is preferably mounted in a hand-held pendant which is connected to electrical box 28 by a flexible lead.

Push buttons 21, 22, 23, 24, 25, 26, 27 supply electricity to linear actuators 2A, 5 or 11 either directly or via relays or via transistors or other known types of electronic devices.

Another preferred embodiment of the invention may use joysticks to control linear actuators 2A, 5,11 via electronic devices.

Another preferred embodiment of the invention may use a touch

2019101388 12 Nov 2019 sensitive surface to control linear actuators 2A, 5, 11 via electronic devices.

Another preferred embodiment of the invention may have the push buttons 21 or 22 or 23 or 24 or 25 or 26 or 27 mounted on a panel which is connected to the electrical system of the invention by a flexible lead. The panel may be hand-held or mounted in any position on the invention.

Another preferred embodiment of the invention may have the push buttons 21 or 22 or 23 or 24 or 25 or 26 or 27 or joysticks or a touch sensitive surface to control linear actuators 2A, 5,11 connected to the electrical system of the invention by a wireless connection. The panel may be handheld or mounted in any position on the frame.

Another preferred embodiment of the invention may have a transducer positioned at pivot 6 so that when an external force is applied to raise actuator arm 2 the transducer will sense the force and supply electricity to linear actuator 5 causing it to extend, moving arm assembly 2 upward through a predominately vertical arc thereby raising the attachment point 1 A. Conversely when an external force is applied to lower the arm 2 the transducer will sense the force and supply electricity to linear actuator 5 causing it to contract, moving arm 2 downward through a predominately vertical arc thereby lowering the attachment point 1A.

Another preferred embodiment of the invention may have a transducer at pivot 3. When an external force is applied to extend arm 2 the said transducer will sense the force and supply electricity to the linear actuator 2A causing arm 2 to extend and move the attachment point 1A away from pivot point 3. Conversely when an external force is applied to contract arm 2

2019101388 12 Nov 2019 the transducer will sense the force and supply electricity to the linear actuator 2A causing arm 2 to retract and move the attachment point 1A toward pivot 3.

Another preferred embodiment may have a transducer at said pivot 12. When an external force is applied to arm 2 to rotate it clockwise when viewed from above the transducer will sense the force and supply electricity to linear actuator 11 causing it to extend to rotate arm 2 thereby rotating the attachment point 1A clockwise through a predominately horizontal arc. Conversely when an external force is applied to arm 2 to rotate it anticlockwise when viewed from above, the transducer will sense the force and supply electricity to linear actuator 11 causing it to contract to rotate arm 2 thereby rotating the attachment point 1A anticlockwise through a predominately horizontal arc when viewed from above relative to inner support post 10.

Another preferred embodiment of the invention may have a transducer positioned at pivot 7 so that when an external force is applied to raise arm 2 the transducer will sense the force and supply electricity to linear actuator 5 causing it to extend, moving the arm 2 upward through a predominately vertical arc thereby raising the attachment point 1 A. Conversely when an external force is applied to lower arm 2 the said transducer will sense the pressure and supply electricity to linear actuator 5 causing it to contract, moving arm 2 downward through a predominately vertical arc relative to pivot 3 thereby lowering the attachment point 1A.

Another preferred embodiment may have a transducer positioned at bearing 9 which can detect force in all directions which is converted

2019101388 12 Nov 2019 electronically to supply electricity to all linear actuators 2A, 5 and 11 to expand or contract to move the attachment point 1A in a required direction.

Another preferred embodiment would have push buttons 21,22, 23, 24, 25, and 26 mounted on a panel mounted on outer support post 4.

It is currently preferred that the aforementioned linear actuators, as currently sourced from Motion Dynamics Australia Pty Ltd of Wetherill Park NSW 2164, have the following specifications:Linear actuator 2A - stroke 300mm force 100 kgs speed 5mm/second

Linear actuator 5 - stroke 100mm force 100 kgs speed 5mm/second

Linear actuator 11 - stroke 50mm force 100 kgs speed 5mm/second

Preferably the inherent properties of these actuators are such that their length cannot be extended or reduced when there is no electrical power applied to the actuator.

An important advantage of these linear actuators over current manual coil positioning frames is that once a chosen position is found and the power supply to the actuators is cut the TMS coil will not subsequently move due to external forces (e.g. weight of cables or contact by patient or operator). Also, when positioning the TMS coil, small precise movements are easier to control with linear actuators than by manual manipulation.

Advantages over current motorised coil positioning frames are that such frames are computer controlled by software applying movements io

2019101388 12 Nov 2019 based on data from inputs such as Magnetic Resonance Imaging and are therefore expensive. The coil positioner frame of the present invention is manually controlled and therefore the manufacturing cost is much less due to the use of commercially available components and the omission of computer, software and interfacing equipment. The required level of operator training is also lower.

A support positioning frame in accordance with this invention can be fixed to a trolley or structure holding other medical equipment or be a stand-alone device. It can also be fixed to a bed or treatment chair.

Claims (5)

1. A support frame for positioning a medical instrument with respect to a patient, said frame in a position of use including an upwardly extending post rotatable on a support base about an axis and a lateral arm of variable length extending out from said post to support an attachment point for said medical instrument and said post and arm being movable through respective horizontal and vertical arcs whereby the position of said attachment point can be selectively raised, lowered, pivoted about and displaced laterally of said axis.

2. The support frame as claimed in claim 1 wherein said post and arm are movable by means of electric linear actuators.

3. The support frame as claimed in claim 2 wherein said lateral arm is formed in part by one of said linear actuators.

4. The support frame as claimed in claim 3 wherein said linear actuators are operable by push button controls, touch sensitive surfaces or transducers located at pivot points in said frame.

5. The support frame as claimed in claim 4 wherein said medical instrument is a TMS coil.