Abstract: A cervical plate for easy reoperation includes: a main plate of a rectangular panel shape, which is installed using a screw on the vertebra from which the disk has been removed during spinal operation to support and fix the surgical site vertebra; and a subsidiary plate of a panel shape, which is installed using a screw during reoperation on an adjacent area to the surgical site where the main plate is installed to support and fix the reoperation site vertebra, wherein the main plate and the subsidiary plate can be connected continuously, thereby allowing additional installation of the subsidiary plate while maintaining the installed state of the main plate.

Abstract: Disclosed is a combined intramedullary and extramedullary bone stabilization and alignment system, which includes both methods and apparatuses for the alignment and stabilization of a first bone or piece of bone to a second bone or piece of bone. Embodiments of the system may include an implant device which has an elongated framework within the intramedullary portion and an extramedullary portion which are cannulated. The cannulated aspect of the framework includes a wire aperture through both the intramedullary portion and the extramedullary portion.

Abstract: The present invention provides a system for fixation of fractures comprising an orthopedic plate configured to abut and support the side of a bone. A cupped drill guide cooperates with the end of the plate and envelops a portion of the bone with a hook and drill guide assembly that can be used to reduce that bone. An expandable cage member can be inserted through the plate into the bone to buttress it, to inhibit subsidence, and to cause or to support the reduction. Optionally the cage member holes can be used for a smaller diameter screw through the use of inserts.

Abstract: An orthopedic implant including an outer surface and at least one opening extending through the outer surface for receiving a fastener for coupling the implant to a patient's bone or bone portion/fragment. The opening including a plurality of fins circumferentially disposed about the opening for engaging threads formed on a head portion of the fastener to secure the fastener to the implant. The plurality of fins being arranged and configured in first and second vertically spaced rows of fins. At least one of the fins including a different configuration, property, etc. relative to at least one of the other plurality of fins. In one embodiment, each of the first and second fins in a vertically stacked relationship includes a different configuration from the other of the first and second fins in that stack. In one embodiment, the different configuration includes a different length, a different thickness, or a combination thereof.

Abstract: The invention relates to a medical fixation system (1) comprising a connecting means (3) extending in a longitudinal direction (A) and a fixing part (5) which, in the assembled state, is adapted to be brought into engagement with the connecting means (3) and to extend over a breaking point, wherein the fixing part (5) comprises a fixing body (7) with a through hole (13) which is adapted to at least partially receive the connecting means (3) in the assembled state, wherein the through hole (13) extends coaxially with a longitudinal axis (L) and is defined by a wall (15) which extends circumferentially around the longitudinal axis (L). The invention proposes that the through hole (13) further comprises at least one cavity (30a-30j) formed in the wall (15), wherein the cavity (30a-30j) is arranged to receive the connecting means (3) in the assembled state at least in sections. The invention also relates to a fixing part (5) for a fixation system (1) and a manufacturing method for manufacturing a fixing part (5).

Abstract: Implants, devices, systems and methods for replacing bone fixation, such as scapula fixation. A bone plate system includes a plate and at least one fastener for insertion through the plate. The plate with a body portion, a base portion positioned inferior to and spaced apart from the body portion, and a connecting member coupled to the body portion on a first end and the base portion on a second end. Methods for implanting the implant are also disclosed.

Abstract: A bone screw is provided that reduces insertion torque when driving the screw into bone while maintaining pull-out strength. The provided bone screw includes one or more threads having a portion with a reduced flank profile that helps reduce the amount of torque required to drive the bone screw into bone. The portion with the reduced flank profile has an equal thread depth or height as the portion of the one or more threads with a non-reduced flank profile, thereby helping to maintain pull-out strength. The reduced flank profile portion is away from the bone screw's insertion tip. As such, the bone screw's non-reduced flank profile portion creates internal female threads that have a correspondingly larger flank profile than the screw's reduced flank profile portion, thereby reducing friction between the reduced flank profile portion of the one or more threads and the interior female thread.

Abstract: The devices, systems, and methods herein described provide uniform biomaterial delivery to produce robust adhesion between an implant (e.g., an implantable screw) and a bone tissue. Furthermore, the devices, systems, and methods of the disclosure overcome challenges associated with the repair of weak or deficient bone and augmentation using injected biomaterials.

Abstract: A bone anchor assembly includes a receiver with a central bore having a seat surface proximate a bottom opening and a channel for receiving a rod, and a snap ring positioned within a recess located in the lower portion of the central bore above the bottom opening. The assembly also includes a bone anchor with a capture portion having a horizontal capture recess and an anchor portion opposite the capture portion, and a scraper ring positioned into an upper end of the capture recess. The scraper ring is engaged by an inwardly-protruding annular edge surface upon the uploading of the capture portion through the bottom opening to drive the scraper ring downward along the recessed surface to sweep the upper portion of the capture recess of bone debris, after which the snap ring snaps into the swept upper portion capture recess to capture and hold the capture portion of the bone anchor to the receiver.

Abstract: Systems and methods are disclosed that provide guidance for controlling the manipulation of a surgical rod according to a target rod shape. In some embodiments, tracked reference frames are secured to the surgical rod and a change in the relative orientation between the first and second trackable reference frames, measured using a tracking system, is employed to provide bend angle feedback suitable for determining when a bend formed by a rod bender conforms to a prescribed bend angle. In some embodiments, the tracked orientation of a rod bender and the tracked orientation of at least one trackable reference frame secured to the surgical rod are employed to provide feedback for controlling the roll angle of the rod bender. An augmented reality overlay showing the target rod contour may be generated based on the positions and orientations of one or both of the tracked reference frames secured to the surgical rod.

Abstract: An acetabular cup impactor includes: a body provided so as to apply force to an acetabular cup and having one end extending toward one side of the acetabular cup; an impactor having a coupling part formed around an axis extending from one side of the body; an alignment guide indicating an impacting direction; and an anteversion guide having a coupling mechanism coupled to the impactor at one end which extends a predetermined distance from the alignment guide, wherein the coupling mechanism of the anteversion guide is provided so as to be detachably coupled to the coupling part of the impactor, and the direction of the force applied by the coupling mechanism to the coupling portion is perpendicular to the extension direction of the impactor while a recess formed on the surface of the coupling part and the surface of the coupling part are gripped in various directions during coupling of the coupling mechanism.

Abstract: An improved system described herein equipped with one or more Pulsed Field Electroporation (PFE) electrodes configured to cause localized and targeted PFE output at the targeted tissue, for example, in an ear, nose, or throat.

Abstract: An ablation balloon catheter includes an outer catheter shaft and an inflatable balloon coupled at a first end to the outer catheter shaft. The catheter includes a translatable nose tip to which a second end of the inflatable balloon is coupled. The catheter has a first electrode basket having a plurality of first splines and a second electrode basket having a plurality of second splines. The second electrode basket is disposed over the first electrode basket and the plurality of first splines are rotationally offset from the plurality of second splines. One or more of the first splines support one or more electrodes and one or more of the second splines support one or more electrodes. The first and second electrode baskets have a collapsed state when the balloon is deflated and a deployed state when the balloon is inflated.

Abstract: A cryogenic probe, comprising: (a) a handle, (b) a shaft disposed distally on the handle, the shaft comprising a generally rigid proximal portion and a generally malleable distal portion, and (c) an active tip disposed distally on the shaft, where the shaft comprises a supply conduit configured to supply a cryogenic fluid to the active tip, an exhaust conduit configured to exhaust spent cryogenic fluid from the active tip, and a vacuum insulating layer disposed around the supply conduit and the exhaust conduit.

Abstract: A medical system and method for estimating a treatment region for a medical treatment device is provided. The system includes a memory; a processor coupled to the memory; and a treatment control module stored in the memory and executable by the processor. The treatment control module generates an estimated treatment region which is an estimate of a treatment region which would have been derived as a result of a numerical model analysis such as a finite element analysis. Advantageously, the estimated treatment region is generated using a fraction of the time it takes to generate the region using the numerical model analysis.

Abstract: An end effector of a medical probe, the end effector including a plurality of elongated support members extending along a longitudinal axis of the end effector and the plurality of elongated support members configured to expand from the longitudinal axis. Each of the plurality of elongated support members includes an electrode landing region. The electrode landing region of each of the plurality of elongated support members includes a first surface facing away from the longitudinal axis and at least one extension extending from the first surface and curving toward the longitudinal axis. The first surface of the electrode landing region includes an electrode coupled to the first surface.

Abstract: A pulsed field ablation effector comprising: (a) an electrode including an electrode surface for delivering electric current to anatomical tissue, and a deformable insulator selectively covering the electrode surface, the deformable insulator configured to deform when contacted by the anatomical tissue to expose the electrode surface. Also disclosed are methods and devices for carrying out electroporation and other forms of ablation concomitant with electroporation.

Abstract: Systems, methods, and devices include a reconfigurable multi-purpose surgical tool with a housing having a plurality of portions for a plurality of surgical tools, such as a cautery tool, a scalpel tool, and/or a forceps tool. A first portion of the housing can house a first surgical tool. The first surgical tool is converted between an in-use configuration and a stored configuration. The stored configuration includes a first surgical tool portion of the first surgical tool being at least partially contained by the housing. The in-use configuration being when the first surgical tool portion is at least partially exposed from the housing. A second portion of the housing partially houses a second surgical tool. The second surgical tool includes another in-use configuration with the second surgical tool at least partially exposed from the housing. A third portion of the housing at least partially houses a third surgical tool.

Abstract: An electrosurgical instrument has a movable tissue cutting mechanism, a shaft housing at least a portion of the movable tissue cutting mechanism, and a pair of opposing jaws rotatable relative to the shaft. Each jaw has an electrically conductive core member, a slot for receiving the cutting mechanism, and a sealing surface. A pin is coupled to the shaft and the jaws. The pin passes through the jaws and the cutting mechanism. A first link is rotatably coupled to the first jaw and a rod. The rod is interior of and translatable relative to the shaft. Each jaw has a coating made of a substantially non-conductive material covering a portion of the conductive core member but exposing the seal surface, whereby the coating limits an energy path from the respective conductive medium to the respective seal surface.

Abstract: A minimally invasive surgical instrument combines a cautery tool and knife tool for performing operative actions, including tissue destruction, coagulation, dissection, and transection. An elongated body has a channel extending in a longitudinal direction to a distal end. The knife tool is situated in the channel and movable along the channel. The cautery tool includes a conductor electrically coupled to a cautery tip. The cautery tip includes a resistive element with a through opening in axial alignment with the channel. The knife tool has a retracted position in which a blade of the knife tool is unexposed, and a fully extended position in which the blade is exposed distal to the through opening.

Abstract: A system may modulate a carrier signal to generate a modulated signal that carries a message for transmission by a first electrode of a catheter. The system may receive an indication of the modulated signal received by a second electrode of the catheter. The system may demodulate the modulated signal received by the second electrode to extract a demodulated message. The system may determine whether the first electrode contacts a target tissue site of a patient based at least in part on the demodulated message.

Abstract: A medical assembly 100 includes a support catheter 102, a therapeutic catheter 104, and a locking assembly 118 coupled to at least one of the support catheter or the therapeutic catheter. The support catheter includes an elongated body defining a guide lumen and configured to position directly within vasculature of a patient. The therapeutic catheter includes an elongated body, one or more therapeutic elements 110 at a distal portion of the elongated body, and an actuation assembly. The elongated body defines a delivery lumen and is configured to move within the guide lumen. The therapeutic elements are configured to extend from the delivery lumen into a treatment site of the patient. The actuation assembly is configured to deploy the therapeutic elements from the delivery lumen into the treatment site. The locking assembly is configured to fix the therapeutic catheter relative to the support catheter while the therapeutic elements are deployed.

Abstract: A catheter for endovascular treatment of a blood vessel includes a treatment portion, a proximal magnetic array positioned proximal to the treatment portion, and a distal magnetic array positioned distal to the treatment portion. Each of the proximal magnetic array and the distal magnetic array include a first magnetic segment having a first polarity, and a second magnetic segment having a second polarity opposite to the first polarity, wherein the second magnetic segment is disposed adjacent to the treatment portion.

Abstract: A pulse generator system is disclosed. The system includes a pulse generator, a power supply and a controller communicatively coupled to the pulse generator and the power supply. The pulse generator may generate pulses in sub-microsecond range duration. The controller is configured to receive one or more desired pulse characteristic values. A computer-implemented method for tuning output pulses of a pulse generator is also disclosed. In some embodiments, the controller receives feedback signals representing a value of a characteristic of or a result of the pulses and generates at least one of the power supply control signal and the pulse generator control signal based on the received feedback signals.

Abstract: A catheter for debulking of an undesired deposit from an inner surface of at least one of a blood vessel wall and a stent located in a blood vessel, the catheter having a tip section comprising: circumferentially-directed laser optics; and a circular-action cutter, wherein said circumferentially-directed laser optics is configured to transmit laser radiation for modifying an area of the undesired deposit thereby preparing said area for penetration of said cutter, wherein said cutter is configured to cut through said modified area and thereby debulk at least a part of the undesired deposit. In addition, a catheter for pacemaker and ICD (Implantable Cardioverter Defibrillator) lead extraction is disclosed.

Abstract: The device comprises at least a laser source (5); an optical fiber (1) with an optical radiation entrance end (1.2) and an optical radiation output end (1.1); and a coupling system (8) for coupling the laser source (5) and the optical fiber (1), adapted to inject an optical radiation emitted by the laser source (5) into the entrance end (1.2) of the optical fiber (1). The optical fiber (1) is a multi-mode optical fiber. The coupling system (8) is adapted to inject the optical radiation into the optical fiber (1) with such an inclination (a) as to reduce or eliminate the fundamental transmission mode and to promote the transmission according to at least one higher-order transmission mode The optical radiation at the output end (1.1) of the optical fiber (1) has a cone-shaped distribution (3) wherein the intensity is maximal on the peripheral volume of an emission cone and is minimal inside the emission cone.

Abstract: Proposed is a method of reconstructing a damaged cartilage of a distal femur to a pre-damaged state for the design of a patient-specific artificial knee joint. The method includes generating a distal femur model (A) having only a bone without a cartilage from image data of a femur captured by a medical imaging device, generating a distal femur model (B) having a damaged cartilage from the image data, extracting a bone cross section for each region in each of the model (A) and the model (B), obtaining a distance between an articular surface of the model (A) and a cartilage surface of the model (B) by using a bone cross section of the model (A) and a bone cross section of the model (B) which are extracted from the same region, and generating a distal femur model (C) with a cartilage reconstructed according to a reconstruction line.

Abstract: A computer-assisted system can comprise an instrument configured to be at least partially inserted through a body wall from an external workspace to an internal workspace within a body; and a controller configured to generate a first three-dimensional model of the internal workspace in which a first portion of the instrument is inserted during performance of a medical procedure using the instrument, generate a second three-dimensional model of an external workspace in which a second portion of the instrument is located during the performance of the medical procedure, based on the first three-dimensional model and the second three-dimensional model, determine an internal geometry within the internal workspace defining a reachable volume within the internal workspace within which the instrument may be positioned, and provide output related to performance of the medical procedure based on the determined internal geometry.

Abstract: The present disclosure describes innovations to improve the use of stereo-EEG (sEEG) intreating epilepsy. The systems and methods include a fully automated platform for generating patient specific head models, a visualization of the tissue that can be recorded by a set of sEEG electrodes, an automated implantation trajectory planning algorithm that incorporates the tissue that can be recorded by a set of sEEG electrodes, and a dynamic source reconstruction algorithm that can visualize the epileptiform activity.

Abstract: Methods and apparatuses for modifying a video image (and/or a video stream) to include one or more virtual trajectory guides to assist a medical professional in performing a surgical procedure. These methods and apparatuses may include allowing the user to easily and quickly identify and/or select one or more regions (landmark regions), determine a surface contour of the identified landmark region, and generate a persistent virtual trajectory guide. Any of these methods may also include identifying (e.g., automatically identifying) one or more tools that may and guiding or assisting the user in manipulating the tools using the one or more virtual trajectory guide.

Abstract: A system may comprise one or more processors and memory having computer readable instructions stored thereon. The computer readable instructions, when executed by the one or more processors, may cause the system to receive image data including a segmented candidate target nodule, receive a seed point, and determine if the segmented candidate target nodule is within a threshold proximity of the seed point. Based on a determination that the segmented candidate target nodule is within the threshold proximity of the seed point, the segmented candidate target nodule may be identified as an identified target nodule. A target nodule boundary corresponding to the identified target nodule may be displayed.

Abstract: A system for treating tissue of a patient's anatomy at a target site. A localizer generates location data associated with the anatomy. A display unit overlays visual content on the anatomy within a field of view observable by a user. A visualization program on a computing device generates a virtual reference frame, identifies viable and non-viable approaches for fixation elements to engage tissue and secure a stabilizer relative to the target site based on patient-specific imaging data, arranges a virtual viability model within the virtual reference frame based on the location data and comprising viable portions associated with viable approaches and non-viable portions associated with non-viable approaches, and renders the virtual viability model in the visual content displayed by the display unit overlaid onto the anatomy within the field of view to assist the user in visualizing at least one of viable approaches and non-viable approaches.

Abstract: A method for identifying material to be removed from a patient may use an imaging device, a display, a control unit, and an insertion device. The method may include obtaining a first set of image data from the imaging device, sending the first set of image data to the control unit from the imaging device, and analyzing the first set of image data based on at least one of a darkness, a contrast, or a saturation. The method may include generating a coded image identifying the material to be removed from the patient to be displayed on the display. The method may further include displaying the coded image on a first screen of the display, and indicating the material to be removed with the insertion device based on the displayed coded image.

Abstract: Systems and methods for determining one or more phases of anatomical movement are provided. A catheter positioned in an anatomical element may be tracked using a tracker configured to track a pose of the catheter. Sensor data corresponding to a plurality of pose information of the catheter may be received from the tracker. One or more phases of motion of the anatomical element may be determined based on the plurality of pose information. An image may be received at a target phase of the one or more phases.

Abstract: New and innovative systems and methods for an integrated surgical navigation and visualization are disclosed. An example system comprises: a single cart providing mobility; a stereoscopic digital surgical microscope; one or more computing devices (e.g., including a single computing device) housing and jointly executing a surgical navigation module and a surgical visualization module, and powered by a single power connection, thus reducing operating room footprint; a single unified display; a processor; and memory. In one embodiment, the system may control a position of a stereoscopic digital surgical microscope with a given reference; provide navigation of a surgical site responsive to user input; provide visualization of the surgical site via a single unified display; and synchronize, in real time, the visualization by integrating navigation information and the visualization of the surgical via the single unified display.

Abstract: Systems and methods for providing navigation indicators for an elongate device include a system configured to determine a pose of the elongate device within a passageway; and based on the pose of the elongate device, display on the display system: an image of the passageway, and one or more navigation indicators associated with one or more directions within a workspace containing the passageway, wherein the one or more navigation indicators are displayed over the image of the passageway.

Abstract: Surgical systems and methods to facilitate surgical navigation involve a scanner to produce a scan of a vessel on a bone and a camera configured to detect markers coupled to the bone. Controller(s) track the bone based on detection of the markers by the camera and determine, based on the scan, one or more characteristics of the vessel on the bone. The controller(s) obtain imaging data of the bone and register the imaging data and the one or more characteristics of the vessel to the bone.

Abstract: A method comprises the steps of: imaging a patient anatomy; selecting an implant strategy for at least one bone fastener having a first member; registering the imaging of the patient anatomy with imaging of a surgical driver; engaging the first member with tissue of the patient anatomy via the surgical driver according to the implant strategy; manipulating the patient anatomy; acquiring data points representative of a position of the first member relative to tissue; and retrieving the data points from a computer database for attaching a second member with the first member. Systems, spinal constructs, implants and surgical instruments are disclosed.

Abstract: A cut guide assembly (600) and a system for mounting assembly on a patient are described. The system includes an ankle clamp (525), an alignment guide (530) configured to be removably attached to the ankle clamp, and the cut guide assembly. The cut guide assembly includes a cut guide (535) and a position tracker (200). The cut guide includes a receiving feature (605) configured to removably attach to at least a portion of the alignment guide, a locking mechanism (610) configured to lock the receiving feature to the at least a portion of the alignment guide, and a plurality of pin receptacles (620), each of the plurality of pin receptacles configured to receive a bone pin (540) configured to affix the cut guide to a patient's bone. The position tracker configured to be affixed to the cut guide when the cut guide is affixed to the patient's bone.

Abstract: A registration fixture for registration of a medical image to a three-dimensional tracking space, includes a base frame, an orientation plate, and a registration plate. The base frame is adapted to be mounted to an x-ray medical imaging device. The orientation plate is attached to the base frame and has a first set of radiopaque markers arranged along at least four radial lines which extend from a center location. The radial lines are angularly spaced apart about the center location. At least three of the radiopaque markers are arranged along each of the radial lines. The registration plate is attached to the base frame and spaced apart from the orientation plate. The registration plate includes a second set of radiopaque markers arranged along a circle.

Abstract: Technologies for monitoring impaction and predicting impaction state during an orthopaedic surgical procedure include one or more impaction sensors that generate sensor data. The surgical procedure includes impaction of an orthopaedic implement such as a surgical instrument or a prosthetic component. An impaction analyzer generates an impaction state prediction with a machine learning model based on the sensor data. The impaction state prediction may include an unseated state, a seated state, and a fracture state. An impaction state user interface outputs the impaction state prediction. A model trainer may train the machine learning model with labeled sensor data.

Abstract: A control apparatus, in a case where a characteristic region related to a path of a lumen of a subject greater than or equal to a predetermined area is included in a field of view of an imaging unit in bending a bending section of a continuum robot in a predetermined direction, estimates an angle restriction value for a bending angle of the bending section based on an end position of the bending section detected after insertion of the bending section into the lumen and structural information about the lumen. In bending the bending section in the predetermined direction, the control apparatus restricts driving of a driving unit so that the bending section bends within the range of the estimated angle restriction value.

Abstract: A surgical robot includes an arm base mover configured to move an arm base configured to support a plurality of arms, an imaging device provided on the arm base, the imaging device being configured to image a patient placed on a surgical table, and a display configured to display, in real time, the patient imaged by the imaging device.

Abstract: Certain aspects relate to systems and techniques for compensating for compression in elongated shafts of medical instruments. Medical instruments can include elongated shafts that may experience compression when articulated. The medical instruments can be attached to instrument positioning devices that are configured to move the medical instruments to compensate for this compression. For example, an instrument positioning device can advance a medical instrument to compensate for compression in an elongated shaft of the medical instrument. In some instances, the amount of compression is determined using a compression compensation parameter. The compression compensation parameter can be determined during a calibration process of the medical instrument.

Abstract: The various embodiments herein relate to robotic surgical systems and devices that use force and/or torque sensors to measure forces applied at various components of the system or device. Certain implementations include robotic surgical devices having one or more force/torque sensors that detect or measure one or more forces applied at or on one or more arms. Other embodiments relate to systems having a robotic surgical device that has one or more sensors and an external controller that has one or more motors such that the sensors transmit information that is used at the controller to actuate the motors to provide haptic feedback to a user.

Abstract: A medical robotic system and method of operating such comprises taking intraoperative external image data of a patient anatomy, and using that image data to generate a modeling adjustment for a control system of the medical robotic system (e.g., updating anatomic model and/or refining instrument registration), and/or adjust a procedure control aspect (e.g., regulating substance or therapy delivery, improving targeting, and/or tracking performance).

Abstract: A method of operating a surgical control system is provided. The method comprises displaying, on a display system, an image of a surgical environment. The display system is configured to move with a head of a user. The method further comprises detecting a manipulator input motion and determining if the manipulator input motion is within a boundary corresponding to a range of motion of a manipulator. The manipulator is coupled to a medical instrument and is configured to control motion of the medical instrument. The method further comprises enabling a virtual manipulator mode if the manipulator input motion exceeds the boundary.

Abstract: The disclosed embodiments relate to systems and methods for a surgical tool or a surgical robotic system. A tool driver is coupled to a distal end of a robotic arm and includes a roll drive disk driven by a rotary motor. One or more processors are configured to detect an attachment of a surgical tool to the tool driver. The surgical tool includes a roll tool disk to be engaged with the roll drive disk of the tool driver, actuate of the roll drive disk through the rotary motor, determine that a measured torque of the rotary motor exceeds a preset torque threshold for a preset period of time since the actuation, and report a successful engagement between the roll drive disk and the roll tool disk.

Abstract: An inference device connected between a surgical robot and a console controlling the surgical robot, the inference device includes an image acquisition unit acquiring an operative field image shot by an imaging unit of the surgical robot, an inference unit performing an inference process on the acquired operative field image, and a transmission unit transmitting at least one of the operative field image acquired by the image acquisition unit and information based on an inference result by the inference unit to the console according to transmission settings by the console.

Abstract: A low-friction medical device includes a first link, a second link, and a tension member. The first link is coupled to an instrument shaft and a first guide path is defined in the first link. The second link is rotatable relative to the first link through an angular range. A distal end portion of the second link is rotatably coupled to a tool member. A curved guide path is defined within the second link between the tool member and the first guide path. A curved guide surface of the second link defines a portion of the second guide path. A first portion of the tension member is parallel to a centerline of the first guide path, and a second portion is coupled to the tool member. A third portion of the tension member between the first and second portions is in contact with the curved guide surface throughout a portion of the angular range.