CA-3033200-C - ROBOT-ASSISTED LASER SURGICAL SYSTEM

Abstract

A system for working biological tissue, the system comprising: a tool comprising a laser operable to perform at least one action of work; positioning means for positioning the tool relative to the biological tissue to perform the at least one action of work; a controller; storage storing electronic program instructions for controlling the controller; and an input means; wherein the controller is operable, under control of the electronic program instructions, to: receive input via the input means; process the input and, on the basis of the processing, control the positioning means and the tool to work the biological tissue.

Inventors

• Riaz Jan Kjell Khan
• Daniel Paul Fick
• William Brett Robertson
• Raymond Ka-Man Sheh
• Charles Ironside
• Richard Chipper

Assignees

• Australian Institute of Robotic Orthopaedics Pty Ltd

Dates

Publication Date

20260505

Application Date

20170809

Priority Date

20160810

Claims (18)

1. 69 THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS: 1. A laser osteotomy system for shaping hard biological tissue including bone, the system comprising: a tool comprising a laser operable to perform at least one action of work comprising laser ablation; positioning means for positioning the tool relative to the hard biological tissue to perform the at least one action of work; an input means; an acoustic sensor operable to measure pressure waves from the hard biological tissue and an environment around the hard biological tissue; and a controller to: receive input via the input means, the input comprising pressure waves measured by the acoustic sensor, perform processing on the input to detect whether the tool has worked an unintended or unexpected biological tissue, or an unintended or unexpected material, wherein detection comprises analyzing the pressure waves to determine whether an ablation was performed by the tool on the hard biological tissue or whether the unintended or unexpected biological tissue was affected by the tool, wherein analyzing the pressure waves comprises correlating the pressure waves to one or more ablation sounds, and on the basis of the processing, control the positioning means and the tool to work the hard biological tissue; and wherein the system is adapted to be used to perform arthroplasty and revisions.
2. 2. The system according to claim 1, wherein processing of the received input performed by the controller, under control of electronic program instructions, comprises an analysis of the received input and a making of a decision on the basis of the analysis 70 and criteria relevant to the at least one action of work to control the positioning means and the tool to work the hard biological tissue; wherein the criteria comprises at least one of: speed of the at least one action of work; accuracy of the at least one action of work; safety of the at least one action of work; and cleanliness of the at least one action of work.
3. 3. The system according to claim 2, wherein as at least part of the analysis, the controller is operable to: generate based on input, or receive as input, a first representation of the hard biological tissue; generate a second representation of the hard biological tissue comprising a planned state of the hard biological tissue after the at least one action of work; and make an assessment on the basis of the first representation of the hard biological tissue and the second representation of the hard biological tissue and use the assessment in the making of a decision.
4. 4. The system according to claim 1, wherein the input means comprises at least one sensor system comprising a set of sensors, wherein individual sensors within the set of sensors are operable to monitor, sense, gather, or measure sensor data and/or information associated with or relating to one or more characteristics, properties and/or parameters of one or more of the system, the hard biological tissue, the surrounding environment, components, or systems or devices associated therewith or coupled thereto, wherein sensors of the set of sensors include those based on one or more of: Raman spectroscopy; hyperspectral imaging; optical imaging; thermal imaging; fluorescence spectroscopy, microscopy, acoustic, metrology, optical coherence tomography, laser power, and any non-invasive sensing.
5. 5. The system according to claim 1, wherein operations performed by the system occur either semi-automatically under control of a surgeon, or automatically without requiring human intervention.
6. 6. 71 The system according to claim 1, wherein the processing comprises altering operation of the laser based on dynamics of interaction between a beam of radiation generated by the laser and the hard biological tissue to control an effect on the hard biological tissue wherein the effect includes: changing the rate of ablation; reducing or mitigating damage to a surface; and increasing the safety and accuracy of the ablation.
7. 7. The system according to claim 1, wherein beams of radiation are generated by the laser in pulses, and laser pulses are batched into ablation runs comprising a pre calculated set of pulses at different locations across the hard biological tissue.
8. 8. The system according to claim 1, wherein the tool comprising the laser includes a sprayer for spraying a liquid on the hard biological tissue to assist in laser ablation and protect the hard biological tissue from thermal damage to at least some extent.
9. 9. The system according to claim 1, wherein the system includes cooling means for cooling one or more components and liquids of the system.
10. 10. The system according to claim 1, comprising shielding for providing protection during working of the hard biological tissue wherein one or more components are shielded to provide one or more of: to provide personal protection; to filter and/or trap and store particulate matter; and to protect the system from contamination through the use of disposable covering.
11. 11. The system according to claim 1, wherein the positioning means comprises an articulated arm to which the tool is attached.
12. 12. The system according to claim 1, wherein the positioning means comprises a fine motion controller adapted for accurately directing a working portion of the tool.
13. 13. The system according to claim 1, wherein the processing comprises using the input to map the geometry of the hard biological tissue and the surrounding environment. 72
14. 14. The system according to claim 1, further comprising a second input means, and wherein further processing by the controller comprises inferring from the second input means the hard biological tissue type and disposition including composition.
15. 15. The system according to claim 1, wherein the tool is adapted to form one or more fiducial marks on the hard biological tissue for tracking thereof.
16. 16. The system according to claim 1, wherein the controller comprises Artificial Intelligence (AI) software including machine perception or machine learning.
17. 17. The system according to claim 1, wherein the tool includes dynamic focusing optics operable to dynamically change the focal length and focus beam diameter of the laser beam at a target distance.
18. 18. A method for operating a tool, the method comprising: storing electronic program instructions for controlling a controller; and controlling the controller via the electronic program instructions, to: receive input via an input means; and process the input to detect whether the tool has worked an unintended or unexpected biological tissue or an unintended or unexpected material based on pressure waves from the hard biological tissue; on the basis of the processing, control the tool operable to perform at least one action of work and positioning means for positioning the tool relative to the material: wherein processing of input performed by the controller comprises an analysis of the input and a making of a decision on the basis of the analysis, and, once a decision has been made, the method comprises controlling the controller, via the electronic program instructions, to initiate an action on the basis of the decision to control the positioning means and the tool; and 73 wherein as at least part of the analysis, the controller is operable, under control of the electronic program instructions, to: generate based on input, or receive as input, a first representation of a hard biological tissue; generate based on input, or receive as input, a second representation of the hard biological tissue, the other representation of the material being a different representation of the hard biological tissue; and make an assessment on the basis of the first representation of the hard biological tissue and the second representation of the hard biological tissue, and use the assessment in the making of the decision.

Description

ROBOT-ASSISTED LASER SURGICAL SYSTEM TECHNICAL FIELD [0001] The present invention relates generally to performing work in respect of laser shaping of biological tissue including bone. [0002] Although the present invention will be described with particular reference to work comprising one or more actions of an orthopaedic surgical procedure performed on dynamic material comprising biological tissue of a living human being, it will be appreciated that implementations of the invention may be used in respect of other biological tissue, and for work comprising additional and/or alternative actions. BACKGROUND [0003] Any discussion of the background art throughout the specification should in no way be considered as an admission that such background art is prior art, nor that such background art is widely known or forms part of the common general knowledge in the field in Australia or worldwide. [0004] [0005] Biological tissue can be difficult to work. One type of biological tissue that is difficult to work is bone. From a materials processing point of view, hard biological tissue, such as bone, is an unfavourable material due to its complex physical nature based on multicomponent (calcium phosphate (ceramic), collagen (organic), and water) and hierarchical structure. [0006] Osteotomy is the surgical cutting of bone. This technique is routinely used in orthopaedic surgery, for example during joint arthroplasty in which parts of an arthritic or damaged joint are removed and replaced with one or more components such as an implant/prosthesis intended to replicate movement of a normal, healthy joint. [0007] A cutting process forms one of the important bone shaping operations during orthopaedic surgeries. Successful joint arthroplasty relies on accurate and precise osteotomy to ensure the alignment of the components and the security of fixation to the bone. Accuracy and quality of bone preparation are key factors in long term implant survivability and good clinical outcome. 2 [0008] For example, the outcome for a recipient of Total Knee Replacement (TKR) surgery is largely dependent on the accuracy of the set of resections performed as part of the surgery to match the internal geometry of the prosthetic implants. Each resection can differ from the ideal cut plane in terms of the position, angle, and flatness of the resulting surface. inaccuracies in the position and angle result in poor function of the prosthetic as well as potential looseness of the implant. Inaccuracies in the flatness of any surface results in "point loading" that can damage the bone and affects the positioning of the implant - decreasing the longevity of the implant and the quality of life of the patient. [0009] As will be described in further detail, current joint surgical techniques lack accuracy in positioning the resections. It has been reported that 20% of total knee replacement patients are dissatisfied with the outcome of the surgery post-operatively and aseptic loosening continues to persist as the leading cause of revision within 10 years of surgery. [0010] Orthopaedic surgery has come a long way through adaptation/integration of modern tools such as sensors and computer aided design (CAD) based generation of patient specific defined joint design and bone machining (shaping/cutting) parameters. That said, currently to perform osteotomy surgeons use conventional mechanical tools such as saws, drills, hammers, ultrasonic cutters, chisels, and grinders. These instruments suffer from a number of disadvantages, including that they lack accuracy and submillimetre precision, cause thermal damage, transfer vibrations and biomechanical stress to adjacent bone, and can cause bone fragmentation. [0011] Particularly, conventional sawing techniques produce uneven bone surfaces with gaps large enough to affect the fixation and position of the implant. Modem surgical instrumentation incorporates various features ( such as narrow slots to guide saw blades) that are designed to improve resection accuracy. Nevertheless, making precise bone cuts with current instrumentation in the clinical setting is difficult, and varus-valgus cutting errors of 4 degrees and flexion-extension errors of 10 degrees have been reported. Clinical studies have shown that successful bone ingrowth into porous coating necessitates both close bone apposition to the porous surface and sufficient initial fixation of the implant. Furthermore, the heat generated by mechanical osteotomy, caused by friction along with heavy mechanical loading, can lead to tissue necrosis (death). Tissue necrosis adversely affects the bony integration into the implant reducing long-term implant survivability. 3 [0012] Currently orthopaedic surgeons rely on a combination of mechanical cutting tools used in conjunction with cutting jigs, computer navigation, and patient matched cutting blocks. Whilst these tools are currently widely accepted as gold standard they each have an inherent degree of error. The acc