APPARATUS FOR ENSURING STRAIN GAUGE ACCURACY IN MEDICAL REUSABLE DEVICE
An apparatus for ensuring strain gauge accuracy including a handle assembly including a controller, an adapter assembly including a tubular housing having a proximal end portion configured to couple to the handle assembly and a distal end portion, a load sensing assembly configured to measure a load exerted on the tubular housing, and a signal processing circuit electrically coupled to the load sensing assembly, a memory coupled to the signal processing circuit, and a calibration assembly including a biasing member having a known spring rate stored as a force value in the memory, the calibration assembly configured to couple to the distal end portion of the adapter assembly. The signal processing circuit is configured to calibrate the adapter assembly with the calibration assembly attached thereto by calculating a correction factor based on a comparison a force of the spring member measured by the load sensing assembly to the force value.
The present application is a continuation of U.S. patent application Ser. No. 16/441,625, filed on Jun. 14, 2019, which claims the benefit of the filing date of provisional U.S. patent application Ser. No 62/695,898, filed Jul. 10, 2018.
BACKGROUND 1. Technical FieldThe present disclosure relates to surgical instrument. More specifically, the present disclosure relates to ensuring accuracy of load sensing devices used in handheld electromechanical surgical systems.
2. Background of Related ArtOne type of surgical instrument is a circular clamping, cutting and stapling device. Such a device may be employed in a surgical procedure to reattach rectum portions that were previously transected, or similar procedures. Conventional circular clamping, cutting, and stapling devices include a pistol or linear grip-styled structure having an elongated shaft extending therefrom and a staple cartridge supported on the distal end of the elongated shaft. In this instance, a physician may insert an anvil assembly of the circular stapling device into a rectum of a patient and maneuver the anvil assembly up the colonic tract of the patient toward the transected rectum portions. The physician may also insert the remainder of the circular stapling device (including the cartridge assembly) through an incision and toward the transected rectum portions. The anvil and cartridge assemblies are approximated toward one another and staples are ejected from the cartridge assembly toward the anvil assembly thereby forming the staples in tissue to affect an end-to-end anastomosis, and an annular knife is fired to core a portion of the clamped tissue portions. After the end-to-end anastomosis has been effected, the circular stapling device is removed from the surgical site.
A number of surgical instrument manufacturers have also developed proprietary powered drive systems for operating and/or manipulating the end effectors. The powered drive systems may include a powered handle assembly, which may be reusable, and a disposable end effector that is removably connected to the powered handle assembly.
Many of the existing end effectors for use with existing powered surgical instruments and/or handle assemblies are driven by a linear driving force. For example, end effectors for performing endo-gastrointestinal anastomosis procedures, end-to-end anastomosis procedures and transverse anastomosis procedures, are actuated by a linear driving force. As such, these end effectors are not compatible with surgical instruments and/or handle assemblies that use rotary motion.
In order to make the linear driven end effectors compatible with powered surgical instruments that use a rotary motion to deliver power, a need exists for adapters to interconnect the linear driven end effectors with the powered rotary driven surgical instruments. Due to powered actuation of these adapters and end effectors various sensors are used to measure mechanical forces and strain imparted on them during use. Accordingly, there is a need for systems and methods to calibrate and/or verify operation of these sensors.
SUMMARYPowered surgical instruments may include various sensors for providing feedback during their operation. Feedback detection enables anvil detection, staple detection, cutting to a force for consistent cutting, controlled tissue compression to avoid tissue damage while maximizing staple formation consistency, excessive load adjustment of stroke to optimized staple formation, and tissue thickness identification. Use of load sensing devices, such as strain gauges, in reusable devices enables many powered, reusable, intelligent devices. Maintaining load sensing device calibration ensures accurate readings or measurements. This device calibration enables a higher degree of load sensing device accuracy confidence, than that gained through reliability testing. This greater confidence may enable load sensing devices, that are unable to establish statistical reliability, to be reused in the field without risk to the patient.
The present disclosure provides for a calibration assembly having accurate feedback detection. This eliminates the problem of un-calibrated feedback detection and the need for reliability testing, which is required to prove that the load sensing device reading correlation to actual forces maintains accuracy. The apparatus incorporates an external fixture to enable the adapter to check the load sensing device accuracy.
According to one embodiment of the present disclosure, an apparatus for ensuring strain gauge accuracy is disclosed. The apparatus includes a handle assembly including a controller, an adapter assembly including a tubular housing having a proximal end portion configured to couple to the handle assembly and a distal end portion, a load sensing assembly configured to measure a load exerted on the tubular housing, and a signal processing circuit electrically coupled to the load sensing assembly, a memory coupled to the signal processing circuit, and a calibration assembly including a biasing member having a known spring rate stored as a force value in the memory, the calibration assembly configured to couple to the distal end portion of the adapter assembly. The signal processing circuit is configured to calibrate the adapter assembly with the calibration assembly attached thereto by calculating a correction factor based on a comparison a force of the spring member measured by the load sensing assembly to the force value.
According to one aspect of the above embodiments, the memory stores the force measured by the load sensing assembly and the correction factor. According to another aspect of the present disclosure the handle assembly includes a display and the controller is configured to display the correction factor on the display. According to a further embodiment of the present disclosure, the biasing member is selectable from a plurality of biasing members and is selectively couplable to the calibration assembly. According to another aspect of the present disclosure the correction factor is used to adjust a measurement by the load sensing assembly during use of the apparatus.
According to one embodiment of the present disclosure, an apparatus for ensuring strain gauge accuracy is disclosed. The apparatus includes a handle assembly including a controller, an adapter assembly which includes a tubular housing having a proximal end portion configured to couple to the handle assembly and a distal end portion, a load sensing assembly configured to measure a load exerted on the tubular housing, and a signal processing circuit electrically coupled to the load sensing assembly, a memory coupled to the signal processing circuit, the memory storing at least one strain value, and a calibration assembly including a hard stop that the adapter assembly, the calibration assembly configured to couple to the distal end portion of the adapter assembly, such that the adapter assembly flexes under load while applying pressure on the hard stop. The signal processing circuit is configured to calibrate the adapter assembly with the calibration assembly attached thereto by calculating a correction factor based on a deviation between the at least one strain value and a force value measured by the load sensing assembly during flexing of the adapter assembly under load while applying pressure on the hard stop.
According to one aspect of the above embodiments, the memory stores the correction factor. According to another aspect of the above embodiments, the correction factor is used to correct at least one strain value. According to a further aspect of the above embodiments, the handle assembly includes a display and the controller is configured to display the correction factor on the display. The correction factor is used to adjust a measurement by the load sensing assembly during use of the apparatus.
Embodiments of the present disclosure are described herein with reference to the accompanying drawings, wherein:
Embodiments of the present disclosure are now described in detail with reference to the drawings in which like reference numerals designate identical or corresponding elements in each of the several views. As used herein, the term “clinician” refers to a doctor, a nurse or any other care provider and may include support personnel. Throughout this description, the term “proximal” will refer to the portion of the device or component thereof that is closer to the clinician and the term “distal” will refer to the portion of the device or component thereof that is farther from the clinician. Additionally, in the drawings and in the description that follows, terms such as front, rear, upper, lower, top, bottom, and similar directional terms are used simply for convenience of description and are not intended to limit the disclosure. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the present disclosure in unnecessary detail.
The present disclosure relates to powered surgical instruments having electronic sensors for monitoring mechanical strain and forces imparted on components of the powered surgical instruments. More particularly, this disclosure relates to load measuring sensors including load sensing devices as well as analog and digital circuitry that are hermetically sealed such that the load sensors are configured to resist harsh environments. In the event that electrical connections of the powered surgical instruments are compromised during use, measurement signals output by the sensors of the present disclosure remain unaltered. In addition, the sensors are programmable allowing for adjustments to gain and offset values in order to optimize the measurement signals.
With reference to
The handle assembly 20 includes a handle housing 22 having a lower housing portion 24, an intermediate housing portion 26 extending from and/or supported on a portion of the lower housing portion 24, and an upper housing portion 28 extending from and/or supported on a portion of the intermediate housing portion 26. As shown in
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Electrical assembly 60 includes the electrical connector 32, a proximal harness assembly 62 having a ribbon cable, a distal harness assembly 64 having a ribbon cable, a load sensing assembly 66, and a distal electrical connector 67. The electrical assembly 60 also includes the distal electrical connector 67 which is configured to selectively mechanically and electrically connect to a chip assembly (not shown) of reload 40.
Electrical connector 32 of electrical assembly 60 is supported within the proximal end portion 30b of the adapter assembly 30. Electrical connector 32 includes the electrical contacts 34 which enable electrical connection to the handle assembly 20. Proximal harness assembly (not shown) is electrically connected to the electrical connector 32.
Load sensing assembly 66 is electrically connected to electrical connector 32 via proximal and distal harness assemblies (not shown). Shown in
For a detailed description of an exemplary powered surgical stapler including an adapter assembly and a reload, reference may be made to commonly owned U.S. Patent Application Publication No. 2016/0310134 to Contini et al., titled “Handheld Electromechanical Surgical System,” filed Apr. 12, 2016 incorporated by reference hereinabove.
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A signal processing circuit is configured to calibrate the adapter assembly 30 with the calibration assembly 700 attached thereto by calculating a correction factor based on a comparison a force of the biasing member measured by the load sensing assembly 66 to the force value. The memory 69 of
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The main controller 38 is configured to display the correction factor on the display screen 146 of
While the adapter assembly 30 spring load may not be calibrated, recalling from memory 69 the previous loading measurements, the main controller 38 can check to see if signal from the load sensing assembly 66 and its relationship to the adapter assembly's 30 spring load has changed. If the ratio of strain gauge signal to the adapter assembly 30 spring load has degraded from its known ratio, the main controller 38 can recognize the deviation and either compensate, signal an error to the user, or decommission the adapter assembly 30. The known ratio may be calibrated in advance at manufacture. In order to compensate for the error, the main controller 38 utilizes the deviation to calculate a correction factor. This correction factor is stored in the memory 69 and may be used to correct for the deviation.
It will be understood that various modifications may be made to the embodiments of the presently disclosed adapter assemblies. Therefore, the above description should not be construed as limiting, but merely as exemplifications of embodiments. Those skilled in the art will envision other modifications within the scope and spirit of the present disclosure.
Claims
1-10. (canceled)
11. An apparatus for ensuring strain gauge accuracy comprising:
- a handle assembly including a controller;
- a tubular housing having a proximal end portion configured to couple to the handle assembly and a distal end portion;
- a load sensing assembly configured to measure a load exerted on the tubular housing;
- a signal processing circuit electrically coupled to the load sensing assembly;
- a memory coupled to the signal processing circuit; and
- a calibration assembly configured to couple to the distal end portion of the tubular housing.
12. The apparatus of claim 11, wherein the memory stores a force measured by the load sensing assembly and a correction factor.
13. The apparatus of claim 12, wherein the handle assembly includes a display and the signal processing circuit is configured to display the correction factor on the display.
14. The apparatus of claim 11, wherein the calibration assembly includes a biasing member that is selectable from a plurality of biasing members and is selectively couplable to the calibration assembly.
15. The apparatus of claim 12, wherein the correction factor is used to adjust a measurement by the load sensing assembly during use of the apparatus.
16. An apparatus for ensuring strain gauge accuracy comprising:
- a handle assembly including a controller;
- a tubular housing having a proximal end portion configured to couple to the handle assembly and a distal end portion;
- a load sensing assembly configured to measure a load exerted on the tubular housing; and
- a signal processing circuit electrically coupled to the load sensing assembly;
- a memory coupled to the signal processing circuit and configured to store at least one strain value; and
- a calibration assembly configured to couple to the distal end portion of the tubular housing, the calibration assembly including a hard stop, such that the tubular housing flexes under load while applying pressure on the hard stop.
17. The apparatus of claim 16, wherein the memory stores a correction factor.
18. The apparatus of claim 17, wherein the correction factor is used to correct the at least one strain value.
19. The apparatus of claim 18, wherein the handle assembly includes a display and the signal processing circuit is configured to display the correction factor on the display.
20. The apparatus of claim 18, wherein the correction factor is used to adjust a measurement by the load sensing assembly during use of the apparatus.
21. A method for ensuring strain gauge accuracy, the method comprising:
- coupling a proximal end portion of a tubular housing to a handle assembly configured to determine accuracy of a strain gauge;
- coupling a calibration assembly to a distal end portion of the tubular housing, the calibration assembly including a hard stop, such that the tubular housing flexes under load while applying pressure on the hard stop;
- measuring, by a load sensing assembly disposed in the tubular housing, a load exerted on the tubular housing; and
- storing at least one strain value to a memory of the handle assembly.
22. The method of claim 21, further comprising storing a correction factor in the memory.
23. The method of claim 22, further comprising correcting the at least one strain value based on the correction factor.
24. The method of claim 23, further comprising displaying the correction factor on a display of the handle assembly.
25. The method of claim 23, further comprising adjusting a measurement by the load sensing assembly during use of the handle assembly based on a correction factor.
26. The method of claim 23, further comprising determining whether a difference between the stored value and the measured force is greater than a predetermined threshold value.
27. The method of claim 26, further comprising determining whether the tubular housing is faulty based on the determination that the difference between the stored value and the measured force is greater than the predetermined threshold value.
28. The method of claim 27, displaying on the display that an adapter assembly of an apparatus is faulty.
29. The method of claim 27, displaying on the display the determined difference.
Type: Application
Filed: Jan 11, 2022
Publication Date: Apr 28, 2022
Inventors: Joseph Eisinger (Northford, CT), Patrick Mozdzierz (Glastonbury, CT), David Valentine (Hamden, CT), Justin Williams (Southbury, CT)
Application Number: 17/573,054