Search

EP-4740895-A2 - KNEE TENSIONER WITH DIGITAL FORCE AND DISPLACEMENT SENSING

EP4740895A2EP 4740895 A2EP4740895 A2EP 4740895A2EP-4740895-A2

Abstract

A system for assessing laxity of a joint including first and second bones is disclosed. The system comprises a tensioner tool comprising a pair of pivotally coupled arms, each arm comprising a proximal handle portion, a distal portion, and an insertion tip selectively coupled to the distal portion. The pair of arms pivot between a compressed configuration for insertion within the joint and an expanded configuration for distraction of the joint by applying a force to the handles, thus spreading the insertion tips. The tensioner tool also comprises a force sensor configured to measure the force applied to the handle portion and a positional sensor configured to measure a separation distance between the pair of arms. The tensioner tool also comprises a communication interface configured to transmit sensor data to a computing device. The system further comprises a processor; and a non-transitory computer-readable medium storing instructions that, when executed, cause the processor to: receive force data from the force sensor of the tensioner tool, calculate, based on the force data, a distraction force exerted to the first and second bones by the insertion tips, receive separation data from the positional sensor of the tensioner tool, and calculate the tip distance based on the separation data

Inventors

  • DUMPE, Samuel C
  • JARAMAZ, BRANISLAV
  • SHEEHAN, Ryan
  • MCKINNON, BRIAN W.
  • FARLEY, DANIEL

Assignees

  • Smith & Nephew Inc.
  • Smith & Nephew Asia Pacific Pte. Limited
  • Smith & Nephew Orthopaedics AG

Dates

Publication Date
20260513
Application Date
20210427

Claims (12)

  1. A system (1100) for assessing laxity of a joint including first and second bones , comprising: a tensioner tool (800, 900, 1000, 1110, 1500), comprising: a pair of arms (805A-B, 905A-B) pivotally coupled at a pivot joint, each arm (805A-B, 905A-B) including a proximal handle portion (810A-B, 910A-B), a distal portion, and an insertion tip (815A-B, 915A-B) selectively coupled to the distal portion, wherein the pair of arms (805A-B, 905A-B) are configured to pivot about a pivot axis between a compressed configuration for insertion between the first and second bones and an expanded configuration for distraction of the first and second bones in response to a force applied to at least one of the proximal handle portions (810A-B, 910A-B), wherein a tip distance between the insertion tips (815A-B, 915A-B) is greater in the expanded configuration than in the compressed configuration; a force sensor (825, 925) coupled to one of the pair of arms (805A-B, 905A-B) and configured to collect force data related to the applied force; a positional sensor (830, 930) configured to collect separation data related to a separation distance between the pair of arms (805A-B, 905A-B); and a communication interface configured to transmit sensor data to a computing device; wherein the system (1100) further comprises: a computing device (1105), comprising: a processor; a non-transitory, computer-readable medium storing instructions that, when executed, cause the processor to: receive force data from the force sensor (825, 925) of the tensioner tool (800, 900, 1000, 1110, 1500), calculate, based on the force data, a distraction force exerted to the first and second bones by the insertion tips (815A-B, 915A-B), receive separation data from the positional sensor (830, 930) of the tensioner tool (800, 900, 1000, 1110, 1500), and calculate the tip distance based on the separation data.
  2. The system (1100) of claim 1, wherein communication interface of the tensioner tool (800, 900, 1000, 1110, 1500) is configured to provide a wired connection to the computing device (1105).
  3. The system (1100) of claim 1, wherein the communication interface of the tensioner (800, 900, 1000, 1110, 1500) tool is a wireless transmission system configured to provide wireless communication with the computing device (1105.
  4. The system (1100) of any preceding claim, wherein the computing device (1105) is a surgical computer (150) of a computer assisted surgical system (100).
  5. The system (1100) of any preceding claim, wherein the system (1100) further comprises one or more displays (1115) in communication with the computing device (1105), wherein the one or more displays (115) are configured to display information relating to the distraction force and distraction distance.
  6. The system (1100) of claim 5, wherein the collected or calculated data is displayed to a user in real-time on the one or more displays (1115).
  7. The system (1100) of claim 5 or 6, wherein the display (1115) is configured to display a total magnitude and direction of the distraction force, a distraction distance, and/or a distraction profile.
  8. The system (1100) of any of claims 5-7, wherein the system (1100) further comprises an augmented reality, AR, headset configured to be worn by the user, wherein the display (1115) is provided by the AR headset.
  9. The system (1100) of any preceding claim, wherein the system (1100) is configured to prompt a user to collect measurements at specific positions along the range of motion of the joint.
  10. The system (1100) of any preceding claim, wherein the system (1100) is configured prompt a user to collect measurements at specific positions along the range of motion of the joint.
  11. The system (1100) of any preceding claim, wherein the computing device (1105) is configured to identify unexpected results and prompt the user to assess one or more components of the system (1100).
  12. A method (1200) of tensioning a joint during a surgical procedure, comprising the steps of: inserting (1205) a tensioner tool (800) into a portion of a joint; applying (1210) a force to a handle portion of the tensioner tool receiving (12215), by a computing device, force data and separation data from one or more locations of the tensioner tool (800); calculating a distraction force and distraction distance at a contact surface of the joint.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application claims the benefit of priority to U.S. Provisional Application No. 63/015,907, titled "Knee Tensioner with Digital Force and Displacement Sensing," filed April 27, 2020, which is incorporated herein by reference in its entirety. TECHNICAL FIELD The present disclosure relates generally to methods, systems, and apparatuses related to a computer-assisted surgical system that includes various hardware and software components that work together to enhance surgical workflows. The disclosed techniques may be applied to, for example, shoulder, hip, and knee arthroplasties, as well as other surgical interventions such as arthroscopic procedures, spinal procedures, maxillofacial procedures, rotator cuff procedures, ligament repair and replacement procedures. More particularly, the present disclosure relates to methods and systems for joint tensioning ligament balancing in a total or partial joint replacement surgical procedure. BACKGROUND Orthopaedic implants are used for resurfacing or replacing joints, such as knees, hips, shoulders, ankles, and elbows, that typically experience high levels of stress and wear or traumatic injury. Implants used to replace these joints must be strong and able to withstand the daily stress and wear at these joints, especially for weight-bearing knee and hip replacements. However, providing a sufficiently strong implant that also fits properly is challenging. Traditional orthopaedic implants are made from polymers, ceramics, metals or other appropriate materials and are formed so that they fit the patient's bone securely. In knee replacement surgeries, for example, typical approaches involve cutting the end of the tibia and/or femur, then fitting a new implant to the cut end. The size of the implant and positioning of the implant are typically determined by a surgeon based on hand measurements and visual estimates. The surgeon may assess the implant position relative to the native bony anatomy and/or the properties of the surrounding soft tissue. Medical professionals may in some cases utilize spacer blocks and/or trial implants to make assessments prior to implantation; however, the assessment may be affected by a variety of factors including the level of experience of the medical professional, and thus remains subjective and imprecise. Further, medical professionals have historically had difficulty in characterizing the properties of the surrounding soft tissues in a quantifiable manner. Further, computer assisted surgical systems allow a user to plan an implant procedure, such as a total knee arthroplasty (TKA), a total hip arthroplasty (THA), or an arthroplasty of another joint, and view a projected outcome prior to performing bone resection. For example, in order to perform virtual planning for a TKA, information regarding two physiological aspects of the patient's knee is required. Specifically, the computer assisted surgical system requires (1) anatomical information pertaining to the patient's femur and tibia, and (2) information pertaining to the soft tissue tension/laxity within the joint. Obtaining information pertaining to the patient's femur and tibia (i.e., the bony anatomy) can be reliably defined in a number of ways whether pre-operatively or intraoperatively. However, the properties of the surrounding soft tissue are much less objective. This lack of objectivity in a major system input has the potential to lead to inconsistent surgical outcomes. During an arthroplasty procedure, a force can be applied to a portion of the patient's anatomy, such as the knee during a TKA. Conventionally, the amount of force, whether applied by hand or by a tool, is applied subjectively, which can lead to inconsistent patient outcomes as a result of improperly characterizing the behavior of soft tissue in response to the applied force. Moreover, difficulties exist in designing tensioner tools having a sufficiently narrow profile to be inserted in a pre-operative joint (especially in patients with a particularly tight joint anatomy). Thus, in many conventional systems, such forces are typically applied only after one or more planar bone cuts have been made to the joint, which limits the manner in which a surgeon can adjust the joint in response to determining the behavior of the soft tissue. While some tensioner tools may facilitate pre-operative tensioning and calculation of an applied force, in many cases the bones of the joint may shift in response to distraction. Quantification of the distraction may be valuable in further characterizing the soft tissue surrounding the joint. Additionally, due to natural variations and/or abnormalities in patient anatomies, many tensioner tools are unable to make consistent and sustained contact with a particular joint surface, resulting in inconsistent joint assessment. The stage of operation at which the tensioner tool is utilized may further affect the geometry of the joint surface. As such, i