Abstract: Implants, instruments, and methods for performing surgical procedures on the spine, including one or more of creating an operative corridor to the spine, delivering implants to the spine, fusing one or more segments of the spine and fixing one or more segments of the spine.

Abstract: Embodiments of a corpectomy method, comprising the steps of: providing a distractor unit comprising at least a first hydraulic cylinder configured to removably receive a piston of a predetermined length during a surgical procedure; providing the piston; providing a plurality of bone screws; affixing a first bone screw of the plurality of bone screws to a first vertebrae of a spine and a second bone screw of the plurality of bone screws to a second vertebrae of the spine; mounting the distractor unit onto the first bone screw and the second bone screw; and extending the hydraulic piston of the distractor unit to cause the first vertebrae and the second vertebrae to move away from each other are disclosed.

Abstract: Systems, devices and methods related to retractor systems that retract tissue to allow access to a surgical site are described. The retractor systems can include a first rotatable arm attachable to a first blade, a second rotatable arm attachable to a second blade and a third linearly translatable arm attachable to a third blade. An attachment mechanism that is attachable to a fourth blade can be removably coupled to a mount on the frame. The retractors systems can also include two blade systems whereby when the retractor is in a closed configuration, the two blades form an oval opening.

Abstract: Disclosed herein are embodiments of stabilizers for use in delivering a replacement heart valve. The stabilizers can receive a portion of a delivery system, such as a handle, to prevent unwanted motion of the delivery system. The stabilizer can include a linear actuator for adjusting a position of the delivery system once held within the stabilizer.

Abstract: A light module includes a substrate, at least one first light source, at least one second light source, and at least one third light source. The first light source is disposed on the substrate and emits a first type of light towards a plant. The second light source is disposed on the substrate and emits a second type of light towards the plant. The third light source is disposed on the substrate and emits a third type of light towards the plant. The first to third types of light have peak wavelengths in different wavelength bands. The first type of light is UV light or blue light in a short wavelength band, the second type of light is UV light, and the third type of light is visible light.

Abstract: A self-supporting surgical retractor is provided for retracting soft tissue and anatomy at a spinal surgical site. The retractor includes a tubular base defining an upper rim and a lower rim and a working channel there between the upper and lower rims, in which the base and lower rim are sized and configured to be seated on adjacent vertebral bodies spanning an intervertebral space. At least two elongated legs are provided, each projecting from the upper rim and each including a fixation feature at a free end thereof. Each of the legs has a length sufficient for the fixation feature to be outside the body of a patient when the lower rim is seated on adjacent vertebral bodies of the patient. The retractor is formed of a radio-transparent or radio-lucent material.

Abstract: Devices, systems and methods for minimally open orthopedic spine surgery are disclosed. A first flexible screw-based retractor is designed to be coupled to each pedicle screw inserted into adjacent vertebral bodies. A retractor system is provided in which a first retractor blade is mounted to one of the screws and a second movable retractor blade is moved away from the first blade, in a medial direction, to create a working channel through which the disc space may be accessed for passing instruments and implants. Light may be incorporated into the device to illuminate the surgical field. One or all of the retractor blades may be made of a sterilizable plastic or metal and be disposable or reusable.

Abstract: Implants, instruments, and methods for performing surgical procedures on the spine, including one or more of creating an operative corridor to the spine, delivering implants to the spine, fusing one or more segments of the spine and fixing one or more segments of the spine.

Abstract: A sternal elevator apparatus is disclosed. The sternal elevator may include a panel, a support beam traversing the panel, and a post coupled to a proximal end of the panel. The apparatus may also include an indicator handle coupled to the sternal elevator, an actuator drive pivotably coupled to the indicator handle, and a housing movably coupled to the actuator drive. The sternal elevator apparatus may have an actuator drive incorporating a linear rack. The housing further may include a cylindrical gear where the cylindrical gear is engaged with the linear rack.

Abstract: A light module includes a substrate, at least one first light source, at least one second light source, and at least one third light source. The first light source is disposed on the substrate and emits a first type of light towards a plant. The second light source is disposed on the substrate and emits a second type of light towards the plant. The third light source is disposed on the substrate and emits a third type of light towards the plant. The first to third types of light have peak wavelengths in different wavelength bands. The first type of light is UV light or blue light in a short wavelength band, the second type of light is UV light, and the third type of light is visible light.

Abstract: A surgical retractor includes a body portion and first and second retractor arms operatively coupled thereto. The body portion includes a rotatable knob, a first blade holder, and a first blade. The first blade is configured for axial displacement with the first blade holder and angulation relative to the first blade holder about a first axis. The first and second retractor arms include respective second and third blades detachably secured thereto. The first and second retractor arms are transitionable between an approximated configuration and a spaced apart configuration. The second and third blades are configured to angulate about respective second and third axes that are defined by the respective first and second retractor arms.

Abstract: A retraction apparatus increases flexibility of retracting tissues around a surgical site, such as during cardiac surgery including mitral valve repair or other surgical procedures. A holder is configured to mount to a fixed rail such as a sternal retractor. A rake element comprises a strap segment having a proximal end slidably received in a slot in the holder. The rake element has a primary rake finger at a distal end of the strap segment configured to grasp and retract tissue at a surgical site and a sub-finger extending perpendicularly via a bendable wing from a side of the primary rake finger adapted to retract adjacent tissue around the surgical site.

Abstract: A retractor system can include a ring frame and a clamp. The ring frame can include a first ring segment and a second ring segment detachably joined to a first ring segment at a joint. The joint can be contained within a cross section of the ring frame that corresponds to a cutting plane perpendicular to an outer surface of the ring frame. The clamp can include an adjustment screw and a first set of jaws and a second set of jaws. The first set of jaws and second set of jaws can define a first aperture configured to receive the ring frame. Rotation of the adjustment screw in a tightening direction can cause the first set of jaws to engage the outer surface of the ring frame and apply a first clamping force to the outer surface of the ring frame received by the first aperture.

Abstract: A method of distracting adjacent vertebral bodies includes inserting a first pin into a first vertebral body, inserting a second pin into a second vertebral body adjacent the first vertebral body, positioning a first retractor blade over the first pin, positioning a second retractor blade over the second pin, attaching a first arm of a frame to the first retractor blade and a second arm of the frame to the second retractor blade, displacing the second arm of the frame away from the first arm to distract the first and second vertebral bodies, inserting prongs of a lateral protector into respective channels defined in the first and second retractor blades, and retracting tissue by a transverse blade of the lateral protector.

Abstract: A surgical retractor assembly is provided having a frame that releasably couples two retractor blades. The retractor blades are coupled to the frame via a pair of mobile carriages that engage a track on the frame. A third retractor blade is configured to be independent of the frame with the first two retractor blades. The independent blade may be fixably positionable in the patient by a direct coupling to a rigid table mount. The retractor assembly may be utilized for creating anterior access to spinal target site while the patient is oriented in the lateral decubitus position.

Abstract: A screw-based retractor comprises an elongate rack having a rack axis, a plurality of arms slidably supported for translational movement on the rack, and a plurality of blades, one each supported by a respective arm at a distal portion thereof. At least one of the arms includes at its distal portion a blade releasably attached thereto. Such blade is attached to a blade receptacle movably attached to the at least one arm in a manner to provide articulation of the blade receptacle and hence the attached blade about an articulation point spaced from and not located on such arm. Such blade is additionally movable relative to the rack in multiple degrees of freedom.

Abstract: A breast securement device for an imaging system is provided. The securement device includes a retainer configured to attach to at least a portion of a patient's breast and a tensioning system coupled to the retainer. The tensioning system is configured to pull the retainer away from a chest wall of the patient so as to apply a pulling force to the patient's breast. The retainer may include a substantially tubular-shaped mesh material having a first end configured to receive at least a portion of the patient's breast and an opposite second end coupled to the tensioning system. In another example, the retainer may include a vacuum bag having a first end configured to receive at least a portion of the patient's breast. In still another example, the retainer may include an adhesive member configured to adhere to the patient's breast.

Abstract: A pivotable wire assembly, including a pivotable wire, including a first section having a first end and a second end, a pivotable section, and a second section connected to the second end via the pivotable section, the second section having an engaging portion, wherein the first section is pivotably displaceable relative to the second section.

Abstract: A retractor system includes a retractor blade and a handle assembly. The retractor blade includes a base portion, a blade extending from the base portion, and a handle mount affixed to the base portion. The handle assembly includes an attachment portion and a retaining rod. The attachment portion includes a slot configured to receive the handle mount, a first cavity adjoining the slot, a retaining member moveable along the first cavity, and a second cavity adjoining the first cavity. Advancement of the retaining rod through the second cavity and into the first cavity advances the retaining member into the slot and into engagement with the handle mount.

Abstract: A surgical retractor system having a frame and a plurality of arms connected thereto is disclosed. At least one arm is moveable relative to the frame and the relative movement is constrained to a direction along the longitudinal axis of the arm. At least one retractor blade is removably connected to each of the plurality of arms. The blade is fixably rotatable about an axis normal to the longitudinal axis of the arm to which it is connected.

Abstract: Surgical access port stabilization systems and methods are described herein. Such systems and methods can be employed to provide ipsilateral stabilization of a surgical access port, e.g., during spinal surgeries. In one embodiment, a surgical system can include an access port configured for percutaneous insertion into a patient to define a channel to a surgical site and an anchor configured for insertion into the patient's bone. Further, the access port can be coupled to the anchor such that a longitudinal axis of the access port and a longitudinal axis of the anchor are non-coaxial. With such a system, a surgeon or other user can access a surgical site through the access port without the need for external or other stabilization of the access port, but can instead position the access port relative to an anchor already placed in the patient's body.

Abstract: A multi-purpose tool includes a jaw head, a locking mechanism pivotably attached to the jaw head, a first handle, and a second handle. The jaw head includes a first jaw having a first tang and a second jaw having a second tang. The locking mechanism includes a projection extending from a lock body. The first tang includes a notch, and the first handle includes a notch configured to align with the notch in the first tang. The aligned notches are configured to receive the projection of the locking mechanism when the locking mechanism is in a locked position. The first handle is fixed to the jaw head when the locking mechanism is in the locked position due to the projection of the locking mechanism contacting both of the aligned notches. The first handle can be removed from the first tang when the locking mechanism is in an unlocked position.

Abstract: A surgical instrument includes an element connectable with a fixture. A first member is independently and selectively movable relative to the element and includes a part engageable with an incision in a cranial-caudal orientation relative to a body to space apart tissue. A second member is independently and selectively movable relative to the element and includes a part engageable with tissue of an anterior portion of the incision relative to the body. A third member is independently and selectively movable relative to the element and includes a part engageable with tissue of a posterior portion of the incision relative to the body. Systems and methods are disclosed.

Abstract: Devices and methods for sternal retraction that reduces bleeding from the cut edges of a sternum and reduces fracturing of the sternum during retraction. The devices and methods involve the use of sternal retractor blades having a certain geometry and inserts placed inside the sternal retractor blades during retraction of the sternotomy incision. The blades and inserts act to tamponade the blood flow from the cut sternal edge and reduce fracturing of the sternum during retraction.

Abstract: A maxillofacial or cranial-facial surgical stabilizer comprising a head frame fully or partially surrounding the head of a patient at an angle running from ears to temple, and that is fixated to the skull of the patient by multiple screws and/or ear holders and screws. One or more flexible/locking arms are removably attached to the head frame for holding and positioning a plurality of interchangeable instruments or accessories. One flexible/locking arm is a medial/center arm accessorized with a dental arch mold. A method of using a head frame to position the pieces of bones during maxillofacial or cranio-facial surgery is also provided.

Abstract: A surgical retractor includes a retractor body and a retractor arm. The retractor arm includes a first portion configured to operatively connect to the retractor body, and a control assembly configured to control movement of a retractor blade. The control assembly includes a base member having a first opening and a second opening, and movable between a first position and second position. The retractor arm further includes a regulating member to control rotation of the base member and move through the first opening of the base member, a connecting member cooperatively connected to the regulating member, and a barrel member in operative slidable engagement with the second opening formed in the base member.

Abstract: Devices for retracting tissue during a minimally-invasive, posterior spinal fusion procedure include a blade positionable along a passageway device connected to a connecting element implanted in a vertebra of the spine, such that the blade covers at least a portion of a longitudinal opening of the passageway device. The blade may be coupled to the passageway device by receiving the passageway device with a receiving portion. Systems for displacing the vertebrae of the spine include first and second extenders, the distal ends of each of which are configured to engage the connecting elements. Each extender may include a shaft configured to be securely engaged within a cage of the respective connecting element. The devices and systems of the present invention may be used in connection with an interbody fusion technique performed through an opening extending between the passageway devices, and an intermediate retractor blade may provide additional tissue retraction.

Abstract: A retractor for use in spinal surgery comprises a frame including a ring member defining a generally central interior space. A plurality of blades is releasably supported respectively to slidable arms each supported on the ring member for individual translational movement relative to the ring member. The blades define an initial substantially enclosed opening that is expandable for use in a surgical procedure. A clutch mechanism supported on the ring member is associated with each arm to individually selectively engage each such arm with a rotatable main gear such that upon rotation of the main gear by a single actuator any one, all or any desired combination of arms may be translated relative to the ring member to move the blades and expand the opening in one or more selected desired directions.

Abstract: A retractor-distractor system comprising a frame with slidably coupled superior and inferior arms extending therefrom. The superior arm comprises a superior clamp arm pivotally coupled to a lateral end of the superior arm, a superior ball joint received between the superior clamp arm and the superior arm, and a superior ball joint lock operable to pivot the superior clamp arm proximate to the superior arm, thereby locking the orientation of the superior ball joint. The inferior arm comprises an inferior clamp arm pivotally coupled to a lateral end of the inferior arm, an inferior ball joint received between the inferior clamp arm and the inferior arm, and an inferior ball joint lock operable to pivot the inferior clamp arm proximate to the inferior arm, thereby locking the orientation of the inferior ball joint. The superior and inferior arms are operable to receive a modular blade to retract and distract tissue.

Abstract: A method for accessing an intervertebral disc space in a patient's body involves making an incision in a region of the patient's body that permits access to the psoas muscle, directing a blade of a first dissecting refractor through the incision and such that a distal end of the first dissecting retractor blade is positioned proximate the intervertebral disc space, and directing, independently of the first dissecting retractor blade, a blade of a second dissecting retractor through the incision and such that a distal end of the second dissecting retractor blade is positioned proximate the intervertebral disc space. During their placement within the patient's body, the first and second dissecting retractor blades are employed in a tissue dissection process. Following the positioning of the distal ends of the first and second dissecting retractor blades proximate the intervertebral disc space, the first and second dissecting refractors are coupled to one another.

Abstract: The claimed subject matter provides systems and/or methods that facilitate improving visualization associated with intubation. A dynamical articulating laryngoscope can include a handle assembly and a blade assembly. The blade assembly can further include a main blade assembly, a proximal blade assembly, and a distal blade assembly. A medium control articulation point can couple the main blade assembly and the proximal blade assembly, and a fine control articulation point can couple the distal blade assembly and the proximal blade assembly. Further, the proximal blade assembly can pivot relative to the main blade assembly around the medium control articulation point and/or the distal blade assembly can pivot relative to the proximal blade assembly around the fine control articulation point. Pivoting about the medium control articulation point and/or the fine control articulation point can be effectuated by one or more blade control components.

Abstract: A retractor system includes a rail having two opposed widened rail portions separated by a narrowed portion, each widened portion engageable by a separate clamp. The clamps are configured to support the rail to a fixed surface, or to support a surgical device. Each clamp may independently be positioned or slid along the rail to a desired location without interference with a clamp on an opposing widened rail portion. A device clamp is formed of spherical mating portions which enable alignment of a surgical device along six degrees of freedom, and tightenable by securing a single fastener. A retractor blade mount enables an angular and tilting disposition of a retractor blade, as well as remote manipulation of the retractor blade.

Abstract: A retractor holder comprises a body poration, a retractor locking portion and a support ring mating portion. The retractor handle can be inserted through a compatible opening bore extending through body portion. The locking portion has a spring-loaded pawl where the leading edge of pawl can mate with teeth of the retractor handle to lock the retractor handle in a fixed position. The mating portion has a slot with an opening on the opposite surface from the leading edge of the pawl to slide onto the support ring. To improve the problem that prior art retractor holders can not rotate an angle on the support ring, a plurality of dowel pins are set in the slot of the support ring mating portion. Thus, the retractor holder can rotate an angle and keep at least one dowel pin to engage with an indentation on support ring.

Abstract: A system for accessing a surgical target site and related methods, involving an initial distraction system for creating an initial distraction corridor, and an assembly capable of distracting from the initial distraction corridor to a secondary distraction corridor and thereafter sequentially receiving a plurality of retractor blades for retracting from the secondary distraction corridor to thereby create an operative corridor to the surgical target site, both of which may be equipped with one or more electrodes for use in detecting the existence of (and optionally the distance and/or direction to) neural structures before, during, and after the establishment of an operative corridor to a surgical target site.

Abstract: A retractor device for spearing the body tissue apart is provided. The retractor includes a housing configured to include a plurality of sections, wherein each section is configured to accommodate placement of at least one blade, a blade holding mechanism configured to secure the at least one blade within the housing, a translation mechanism configured to provide translation movement of at least one of the sections, and a rotation mechanism configured to provide rotation movement of at least one blade.

Abstract: A spine retractor and distractor device comprises spinal process clamps and a retractor assembly, which may be rotatably coupled with the spinal process clamps. The retractor assembly may include a retractor ring, or frame, and a plurality of retractor blades adjustably coupled to the frame, e.g., by clamps. The spinal process clamps can maintain a grip on the spinal processes of the patient, and distraction pliers may be used to impart a distraction force on the spinal process clamps to distract the spinal segments. Additionally, other components, features, or tools, e.g., a light source and/or a camera, can be mounted on the instrument.

Abstract: A retractor ring assembly includes a ring holder that has a first selectively engaged connection and a second selectively engaged connection. A first and second ring portion each has a proximal end and a distal end. The proximal end of the first and second ring portions are selectively connected to the respective first and second selectively engaged connections of the ring holder. The distal end of the first ring portion has a third selectively engaged connection. The distal end of the second ring portion has a fourth selectively engaged connection. The third selectively engaged connection and the fourth selectively engaged connection are connectable to form a reinforced closed ring configuration, and are disconnectable to form an open ring configuration.

Abstract: A retractor for use in spinal surgery comprises a frame including a ring member defining a generally central interior space. A plurality of blades is releasably supported respectively to slidable arms each supported on the ring member for individual translational movement relative to the ring member. The blades define an initial substantially enclosed opening that is expandable for use in a surgical procedure. A clutch mechanism supported on the ring member is associated with each arm to individually selectively engage each such arm with a rotatable main gear such that upon rotation of the main gear by a single actuator any one, all or any desired combination of arms may be translated relative to the ring member to move the blades and expand the opening in one or more selected desired directions.

Abstract: A retractor for use in spinal surgery comprises a frame including a ring member defining a generally central interior space. A plurality of blades is releasably supported respectively to slidable arms each supported on the ring member for individual translational movement relative to the ring member. The blades define an initial substantially enclosed opening that is expandable for use in a surgical procedure. A clutch mechanism supported on the ring member is associated with each arm to individually selectively engage each such arm with a rotatable main gear such that upon rotation of the main gear by a single actuator any one, all or any desired combination of arms may be translated relative to the ring member to move the blades and expand the opening in one or more selected desired directions.

Abstract: A retractor device for spearing the body tissue apart is provided. The retractor includes a housing configured to include a plurality of sections, wherein each section is configured to accommodate placement of at least one blade, a blade holding mechanism configured to secure the at least one blade within the housing, a translation mechanism configured to provide translation movement of at least one of the sections, and a rotation mechanism configured to provide rotation movement of at least one blade.

Abstract: A surgical stabilizer for use with a surgical site retractor has a base, a bendable arm, and a distal cuff adapted to resiliently hold a tube of an elongated port-access device. The cuff may have a body defining a partial enclosure within which is held a highly flexible gasket having a slit for resiliently receiving the tube. The surgical site retractor may have a collapsible ring and a flexible outer portion attached thereto, the ring being sized to pass through an intercostal incision and expand therein under adjacent ribs to prevent removal, and the flexible outer portion extending out of the incision and drawing over the stabilizer base to mutually secure the retractor and base. The port-access tube may be for a heart valve delivery system using an elongated port-access device for transapically delivering a prosthetic heart valve to the aortic valve annulus.

Abstract: A transoral retractor in accordance with one embodiment of the invention includes a handle, a retractor blade mount attached to the handle, a frame and a pivot mechanism to pivotally mount the frame to the handle. In another embodiment the frame includes side members and is configured with the side members at transverse locations that will be near or beyond the side of the patient's head. The frame and/or pivot mechanism are configured to locate a plane of the frame generally at or near the plane of the patient's oral commissaries, with the side members located below the plane of the oral commissaries.

Abstract: A method for retracting body tissue providing a retractor system that includes a rail having two opposed widened rail portions separated by a narrowed portion, each widened portion engageable by a separate clamp. The clamps are configured to support the rail to a fixed surface, or to support a surgical device. Each clamp may independently be positioned or slid along the rail to a desired location without interference with a clamp on an opposing widened rail portion. A device clamp is formed of spherical mating portions which enable alignment of a surgical device along six degrees of freedom, and tightenable by securing a single fastener. A retractor blade mount enables an angular and tilting disposition of a retractor blade, as well as remote manipulation of the retractor blade.

Abstract: An instrument for spinal surgery for retracting soft tissue and mounting between a superior spinous process and an inferior spinous process includes a relatively rigid frame, a first retractor blade mounted to the frame and a distractor element movably mounted to the frame. The distractor element has a body, a proximal end and a distal end. The distractor element has a thickness and a length. The distractor element is configured for mounting between the superior and inferior spinous processes in a working configuration. The distractor element is generally tapered at the distal end in an insertion configuration. The instrument also includes an insertion shaft attached to the proximal end and a first shaft joint mounted between the frame and the insertion shaft.

Abstract: Various exemplary embodiments relate to a method of performing an anterior approach hip replacement using a retractor assembly. The method may include: providing a retractor assembly including a first vertical post, a plurality of accessory arms mounted to the first post, a second vertical post, and a femur distractor mounted to the second post; exposing a surgical site including the femoral neck and acetabulum using a plurality of retractors secured to the accessory arms; cutting the femoral neck to remove the femoral head; preparing the acetabulum for insertion of an acetabular cup; preparing the femur for insertion of a femoral implant by lifting the femur using a femur hook and the femur distractor; and closing the surgical site. In various alternative embodiments, the retractors may include a lesser trochanteric retractor coming from a direct medial approach and a greater trochanteric retractor coming from a lateral, posterior, proximal approach.

Abstract: A ratchet assembly for multi-dimensional movement and placement of a retractor blade includes a retractor blade holder, a housing member, a rotating indexer and a self-retaining locking mechanism. The retractor blade holder is shaped and dimensioned to receive a stem of a retractor blade and includes a locking mechanism that enables selective lateral adjustment of the retractor blade relative to the retractor blade holder. The retractor blade holder is mated to the housing member and is vertically pivotable with respect to the housing member to enable selective vertical pivoting adjustment of the retractor blade relative to the housing member. The rotating indexer is mated to the housing member, and the housing member is rotatable with respect to the rotating indexer so that the retractor blade holder, the housing member and the retractor blade are able to selectively rotate about the longitudinal axis of the rotating indexer.

Abstract: A retractor for use in spinal surgery comprises a frame including a ring member defining a generally central interior space. A plurality of blades is releasably supported respectively to slidable arms each supported on the ring member for individual translational movement relative to the ring member. The blades define an initial substantially enclosed opening that is expandable for use in a surgical procedure. A clutch mechanism supported on the ring member is associated with each arm to individually selectively engage each such arm with a rotatable main gear such that upon rotation of the main gear by a single actuator any one, all or any desired combination of arms may be translated relative to the ring member to move the blades and expand the opening in one or more selected desired directions.

Abstract: A vaginal speculum includes a first rod supporting a first arm that is slidable along the first rod, a first valve being attached to the first arm, and a second arm, a second valve being attached to the second arm. The vaginal speculum further includes a second rod supporting a third arm that is slidable along the second rod, a third valve being attached to the third arm, and a fourth arm, a fourth valve being attached to the fourth arm. The first rod and the second rod are rigidly connected to one another.

Abstract: This invention includes surgical retractors that comprise an expandable frame that includes at least two base components, a connector, and at least two retractor blades attached to the expandable frame. Also included are surgical retractors that comprise a housing component that includes a cylindrical portion and a contiguous blade portion, assemblies comprising a surgical retractor assembled to at least one obtruator, illuminated surgical cannulas, and methods of using the same during a surgical procedure.

Abstract: A retraction device adapted to retract tissue is provided, comprising at least one pair of opposed retraction members, with each retraction member being capable of operably engaging the tissue to be retracted. A drive mechanism is operably engaged with at least one of each pair of retraction members for separating one of each pair of retraction members from the other to retract the tissue. A measuring device is operably engaged with at least one of the drive mechanism and one of each pair of retraction members, for determining and/or controlling a magnitude and/or rate of a force and/or strain imparted to the tissue by the drive mechanism via the retraction members as the tissue is being retracted. Associated devices and methods are also provided.