Abstract: An X-ray imaging system includes a gantry, rotatable about an axis of rotation, a radiation source mounted on the gantry and configured to emit radiation, and one or more detectors configured to detect the emitted radiation. The gantry includes a gear assembly coupled to a motor to enable rotation of the gantry, wherein the gear assembly comprises a gantry gear. The gantry includes an encoder for detecting position of the gantry, wherein the encoder comprises an encoder gear meshed with the gantry gear. The gantry also includes a gear re-engagement assembly configured to couple to the encoder and to force the encoder gear into correct engagement with the gantry gear when the encoder gear becomes disengaged from the gantry gear. As such, the gear re-engagement assembly keeps engagement of the encoder gear and the gantry gear to maintain the important gantry position tracking.

Abstract: According to one embodiment, the X-ray tube generates X-rays. The X-ray detector detects the X-rays transmitted through a subject. The data acquisition circuitry acquires count data concerning a count number of the detected X-rays for energy bands. The memory circuitry stores data of a response function that associates incident X-rays on the X-ray detector with a response characteristic of a system including the X-ray detector and the data acquisition circuitry. The processing circuitry calculates an X-ray absorption amount of each of a plurality of base substances based on the count data concerning the energy bands acquired by the data acquisition circuitry, an energy spectrum of the incident X-rays, and the response function.

Abstract: Imaging techniques that may be used in applications such as differential phase contrast imaging are disclosed that include, for example, configuring a beam source and a beam detector such that a beam connects the two, positioning an object, a phase grating and an analyzer grating in the beam path, producing multiple data sets based on various analyzer grating positions, and conducting a regression analysis using a predetermined function having a set of fitting coefficients to establish those fitting coefficients. In those techniques, the fitting coefficients may be used to characterize a set of interference properties associated with the object.

Abstract: An image including the marker M is continuously collected every constant time from the images and template matching is performed by utilizing the first template image stored in advance in the template image memory element relative to the image including the marker M. And the image including the marker M after pattern matching specified by the template matching element is clipped as a template image and is stored in the template image memory. Then, the image including the marker M is acquired from the next images continuously collected every constant time. Thereafter, the template matching is performed by utilizing the second template image stored just therebefore in the template image memory element relative to the image including the marker M. Once the second template matching is completed, the image including the marker M is clipped as the next second template image since the pattern matching is identified by the template matching element, and is stored.

Abstract: An image processing apparatus includes an acquiring unit and an image processing unit. The acquiring unit acquires a radiographic image acquired by irradiating a radiation on an object and a scattered-ray component contained in the radiographic image, wherein the scattered-ray component originates from a scattered ray which is a radiation scattered in the object. The image processing unit performs an image process on the radiographic image in accordance with an instruction, wherein the image processing unit performs an image process based on a radiographic image acquired by the acquiring unit and a scattered-ray component acquired by the acquiring unit in a case where an instruction to perform the image process is received again.

Abstract: A portable medical imaging system includes a movable station, a detector panel, an X-ray beam transmitter, and a controller. The movable station includes a c-arm having a first end and a second end that are movable along an arc relative to the movable station. The detector panel is attached to the first end of the movable c-arm. The X-ray beam transmitter faces the detector panel and is attached to the second end of the c-arm. The X-ray beam transmitter contains a collimator that forms a window through which an X-ray beam is transmitted toward the detector panel. The collimator is configured to move the widow in a lateral direction across a direction of the arc. The controller is configured to control movement of the window by the collimator to steer the X-ray beam laterally across the detector panel.

Abstract: A method for continuously evaluating an X-ray unit. The method includes placing an X-ray sensor converter having a photo diode and a scintillation crystal in a path of an X-ray beam emitted by the X-ray unit, using the X-ray sensor converter to convert an X-ray beam energy into an electric signal, providing an amplifier connected to the X-ray sensor converter, conveying the electric signal from the X-ray sensor converter to the amplifier, amplifying the electric signal with the amplifier, and measuring a spectrum of the X-ray tube energy by continuously sampling and quantifying the amplified electric signal.

Abstract: There is provided a sound and vibration information collecting mechanism, which collects low-frequency sound and vibration information with a predetermined frequency or lower from a detection target, the mechanism including a resonance layer, which includes a natural oscillator having a natural frequency within a frequency band of the sound and vibration information being a collection target, and generates a resonance carrier by the natural oscillator emphasizing the sound and vibration information; and a sensor, which detects the resonance carrier. The mechanism detects a bioacoustic signal and a biosignal more accurately than conventionally.

Abstract: A noninvasive system for detecting and processing PCG and ECG waveforms includes an electronic acoustic stethoscope and a server computer. Heart sounds of a patient are measured using an acoustic transducer of a chestpiece of the electronic acoustic stethoscope, the heart sounds are sent to an earpiece of the electronic acoustic stethoscope, and a PCG waveform is created. Heart electrical signals of the patient are measured using at least four electrodes of the chestpiece and an ECG waveform is created. The PCG waveform and/or the ECG waveform are transmitted to the server computer using a wireless communication device of the chestpiece. The PCG waveform is processed for additional PCG information and/or the ECG waveform is processed for additional ECG information using the server computer. Access to the additional PCG information and/or additional ECG information is provided to at least one client device using the server computer.

Abstract: Position coordinate information of each point three-dimensionally forming a tissue corresponding to a diagnosis target at each time phase is obtained, a quantitative value for evaluating the movement of the tissue corresponding to the diagnosis target is calculated by using the position information, and the result is output in a predetermined form. Accordingly, since the quantitative value for evaluating the movement is calculated by using the three-dimensional position coordinate information without converting wall movement information obtained by a three-dimensional tracking process into two-dimensional information, it is possible to provide medical information with a higher degree of precision.

Abstract: An ultrasound apparatus includes a base, a housing extending upwardly from the base and having opposed lateral sides, the housing being configured to support an operator console and display, and a storage bin received in a recess in the housing. The storage bin is movable from a first position in which the storage bin is received within the recess of the housing, and a second position in which the storage bin extends from one of the lateral sides of the housing.

Abstract: An ultrasonic sensor includes a vibration plate, a first electrode, a piezoelectric body, and a second electrode. The first electrode is laminated on the vibration plate, that has a length along a surface of the vibration plate in a first direction, and that has a width Wbe along the surface of the vibration plate in a second direction that is orthogonal to the first direction. The width Wbe is not more than the length. The piezoelectric body is laminated on the first electrode and has a width Wpz in the second direction. The second electrode is laminated on the piezoelectric body. A ratio Wbe/Wpz between the width Wbe of the first electrode and the width Wpz of the piezoelectric body is not less than 0.1 and not more than 0.8.

Abstract: A method is described for acquiring 3D quantitative ultrasound elastography volumes. A 2D ultrasound transducer scans a volume of tissue through which shear waves are created using an external vibration source, the synchronized measurement of tissue motion within the plane of the ultrasound transducer with the measurement of the transducer location in space, the reconstruction of tissue displacements and/or tissue velocities in time and space over a volume from this synchronized measurement, and the computation of one or several mechanical properties of tissue from this volumetric measurement of displacements. The tissue motion in the plane of the transducer may be measured at a high effective frame rate in the axial direction of the transducer, or in the axial and lateral directions of the transducer. The tissue displacements and/or tissue velocities over the measured volume may be interpolated over a regular grid in order to facilitate computation of mechanical properties.

Abstract: Sold-state intravascular ultrasound (IVUS) imaging devices, systems, and methods are provided. Some embodiments of the present disclosure are particularly directed to flexible and efficient systems for focusing IVUS echo data received from transducers including polymer piezoelectric micro-machined ultrasound transducers (PMUTs). In one embodiment, an ultrasound processing system includes first and second aperture engines coupled to an engine controller, which provides aperture assignments to the first and second aperture engines. The aperture engines receive the assignment and a portion of A-line data, perform one or more focusing process on the received A-line data, and produce focused data in accordance with the aperture assignment. In some embodiments, once an aperture engine has produced focused data, the engine controller clears the aperture engine and assigns another aperture.

Abstract: A scan head for an ultrasound imaging device has a body that encloses a number of ultrasound transducers and controlling electronics. The electronics are sealed in the body of the scan head. The scan head has a fan that is configured to remove heat caused by the operation of the electronics. The motor is magnetically controlled and has controlling electronics that are sealed in the body of the scan head. In one embodiment, an airflow channel surrounds the electronics in the scan head and the fan is configured to move air through the airflow channel. In another embodiment, the electronics are thermally coupled to a heat exchanger heat via a conductive substrate and the fan is configured to move air over the heat exchanger.

Abstract: With the Quantified Self movement becoming prevalent, more people are looking to incorporate technology to acquire data regarding aspects of a person's daily life in terms of inputs (e.g. food consumed, quality of surrounding air), states (e.g. blood oxygen levels, body temperature), and/or performance. This self-monitoring concept combines wearable sensors with computing devices to produce an output to improve daily functioning. Disclosed is a device that senses and measures the created cavity temperature (CCT) within an artificial cavity in the wearer's body. This current device provides a wearable thermometer that measures temperature for a convenient, comfortable method of continuously tracking the wearer's temperature.

Abstract: The electrophysiological diagnostic catheter obtains an endomyocardial biopsy of heart tissues. The catheter includes a manipulation handgrip, main channel, distal ring and diagnostic rings connected with electrical connections. There is a centrally located, open internal channel, wherein inlet/outlet of internal channel is located in the distal ring, or is guided and monitored using a system for 3D electroanatomical mapping.

Abstract: An apparatus for displacing an implant, such as a pacemaker or ICD generator or loop recorder, which can be used during surgical procedures to facilitates manipulation of the implanted device. The apparatus can be used to apply force to the implant in order for the operator to tug to loosen the implanted device without causing unnecessary movement or dislodgement of implanted leads that are connected to the implanted device. The apparatus can have features of various shapes and sizes depending on the size of the patient as well as size and shape of the implanted device.

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 orthopedic implant includes a bridge and at least a first leg extending from a first end of the bridge and a second lee extending from the second end of the bridge. The bridge includes a first upper section and a second lower section. The first upper section includes surfaces that are non-orthogonal and taper from a central surface to provide the first upper section with a non-uniform cross-section. The second lower section includes surfaces that are non-orthogonal and taper from a central surface to provide the second lower section with a non-uniform cross-section. The non-uniform cross-sections of the first upper section and the second lower section flatten the profile of the bridge, thereby producing an orthopedic implant with a smooth composite surface.

Abstract: The invention provides a fastening device for laparoscopic hernia repair. The coordinated operation of two insertion members stabilizes a fastener during closure and locking to ensure that the fastener is locked in the intended location before the device releases from the fastener. One of the insertion members includes a pair of prongs that exhibit a closed configuration when they are disposed in a recess at an end of the fastener. The fastener has a hook at one end and a loop at the other end. The insertion members push the fastener out from the device and through the tissue. A curvature in at least one of the insertion members pushes the hook through the loop all while the prongs are in the recess in the fastener, thereby stabilizing the fastener with respect to the device.

Abstract: A surgical stapling apparatus is disclosed which comprises a shaft, an end effector, and an articulation joint, wherein the end effector is rotatable relative to the shaft about the articulation joint. The stapling apparatus further comprises a firing drive responsive to an input, an articulation drive, and a switch assembly configured to selectively couple the articulation drive to the input. The switch assembly is configured to lock the articulation drive in position when the articulation drive is not coupled to the input.

Abstract: A surgical apparatus is provided. The surgical apparatus includes a proximal body portion, a distal body portion selectively articulable relative to the proximal body portion at an articulation joint, and a first drive gear disposed within the distal body portion. The distal body portion has a diameter and a length. The length of the distal body portion is substantially the same as the diameter of the distal body portion.

Abstract: A surgical device is provided that includes a jaw portion, having a first jaw in opposed correspondence with a second jaw, the second jaw including a surgical member. The surgical device may include a shaft portion coupled to a proximal end of the jaw portion and at least one motor configured to rotate the jaw portion relative to the shaft portion, to move the jaw portion relative to the shaft portion, move the first jaw relative to the second jaw and move the surgical member within the second jaw. The surgical member may be prevented from moving within the second jaw unless the first jaw is in a closed position relative to the second jaw. Advantageously, the surgical member may include one or both a cutting element or a stapling element, disposed within one of the jaws.

Abstract: A surgical end effector for cutting and stapling tissue is disclosed. The surgical end effector comprises a first iaw and second iaw configured to clamp tissue when the first and second jaws are in a clamped position. The end effector further comprises a replaceable staple cartridge and a tissue thickness compensator configured to adapt to variations in the thickness of the clamped tissue. The tissue thickness compensator comprises three fibrous patterns oriented in three different directions and a tissue contacting surface comprising a textured surface. The textures surface is configured to minimize movement of the tissue relative to the tissue thickness compensator. The end effector further comprises an I-beam comprising a first camming member, a second camming member, and a cutting member. The end effector further comprises a first attachment member and a second attachment member configured to be progressively released by said cutting member.

Abstract: A powered surgical instrument is disclosed comprising a motor, a shaft extending from the housing, an end effector extending from the shaft, a power source, a processor, a motor controller, and a control circuit. The control circuit comprises a first segment configured to supply the processor with a first voltage from the power source, and a second segment configured to supply the motor controller with a second voltage from the power source. The second voltage is different than the first voltage. The powered surgical instrument further comprises means for shifting power to the first segment when the second segment experiences a power drop due to high power demand from the motor.

Abstract: The present disclosure relates to an electromechanical surgical system and methods for use thereof including a surgical instrument having a controller, and an end effector selectively and removably connectable to the surgical instrument, wherein the controller enters an emergency retraction mode when at least one input element of the surgical system is incapable of providing control signals to the controller to operate a motor, wherein the emergency retraction mode activates the motor to withdraw a drive assembly from any advanced position thereof.

Abstract: A loading unit includes a shell assembly and a locking band. The shell assembly has a proximally extending annular body. The annular body defines two hook openings that oppose one another, a lug opening positioned between the hook openings, and a central passage for receiving a portion of a surgical instrument. The locking band has an arced body with two ends, a retention hook positioned adjacent each end of the body and extending from the inner surface of the body. Each of the retention hooks is disposed within a respective one of the hook opening to retain a respective one of the ends of the locking band to the annular body. The lug is disposable through the lug opening into the central passage to secure the loading unit to a surgical instrument.

Abstract: A loading unit assembly includes a shell assembly and a locking collar. The shell assembly has a proximally extending annular ring that defines a cylindrical opening. The annular ring defines a lock opening that passes through the annular ring. The shell assembly defines a retention slot that is adjacent the annular ring on an opposite side of the annular ring from the lock opening. The locking collar is positioned about the annular ring and has a body, a lock, and a retention tab. The body includes a release surface. The locking collar has a locked configuration wherein the lock extends into the cylindrical opening and an unlocked configuration wherein the lock is disposed outwardly of the cylindrical opening. The side of the locking collar opposite the lock is prevented from moving outwardly in relation to the annular ring when the release surface is pressed inwardly towards the annular ring.

Abstract: Apparatus and methods for preparing a bone socket, such as the glenoid of the scapula, to receive a prosthetic component. The apparatus is an orthopedic instrument (reamer) used for the preparation of bone surface for the insertion of an implant. The reamer includes an elongate shaft, a connecting system (for example, a quick connect system), and a cutting head having a specific configuration, i.e., in the shape of a Nautilus shell having a logarithmic spiral. The cutting head is provided with a plurality of spokes that have different radii or lengths (that confer a non-constant non-uniform radius to the overall cutting head).

Abstract: A method and a surgical alignment system for use in the positioning of a prosthetic component on or in a bone of a subject. The system includes an intramedullary member and a jig member which are connectable to each other to position the jig member relative to the intramedullary member in a sagittal orientation. The jig 5 member includes an elongate arm and the jig member is moveable in an axial plane and at least rotatable in a coronal plane relative to the intramedullary member to align the elongate arm with the bony landmark.

Abstract: A recanalization catheter for facilitating re-entry into a lumen of a blood vessel from a subintimal space. The recanalization catheter includes first and second mechanically actuatable wings positioned at a distal region of the elongate shaft of the catheter that are actuatable between a retracted position and an expanded position. In the retracted position the mechanically actuatable wings are positioned in first and second elongate channels defined in the elongate shaft, and in the expanded position the mechanically actuatable wings extend outward from the first and second elongate channels. The actuatable wings extend in an arcuate path away from the elongate shaft in the expanded position to be positionable in a circumferential orientation within a subintimal space formed in a vessel wall to automatically orient a lateral port of the elongate shaft toward the true lumen.

Abstract: A lithotripter includes a motor operable to produce a rotational motion, a first cam with a first set of teeth, and a second cam with a second set of teeth configured to selectively engage with the first set of teeth. The first cam is coupled to the motor so that the rotational motion produced by the motor produces rotational motion of the first cam, and the selective engagement between the first set of teeth and the second set of teeth converts the rotational motion of the first cam to a linear waveform that is transmitted through the second cam. The motor, the first cam, and the second cam are disposed in a driver housing, and a wave guide shaft is coupled to the second cam. The wave guide shaft transmits the linear waveform to at least one urinary tract stone to break up the at least one urinary tract stone into fragments.

Abstract: A medical device comprising a cannula having a stone extracting unit on its distal end and a hand piece on its proximal end for operating the unit through the cannula. The unit includes more than four annularly arranged tubular elements with fixed proximal ends and distal ends movable between opened and closed position by the movement of an equal number of wire elements extending through the tubular elements with their distal free ends fixed to the distal ends of tubular elements so as to define a 5 or 6 pointed star configuration.

Abstract: A switch mechanism for a medical manipulator, the switch mechanism including a moveable switching operation part, moving-side contacts provided to the switching operation part, and fixed-side contacts capable of contacting the moving-side contacts. At least the electrical-contact sections of the moving-side contacts and of the fixed-side contacts are formed from a corrosion-resistant material.

Abstract: The present invention related to a coring tool for preparing a core or opening through tissue and methods of use thereof.

Abstract: A surgical device includes a handle body extending along a handle axis. The handle body is releasably engaged to a tunneling shaft extending along a shaft axis transverse to the handle axis. At least one tool is mounted to the handle body. Each tool includes a working end adapted to actuate an element of an implantable device.

Abstract: A cutting device for performing a surgical procedure includes a cannula extending between a proximal end and a distal end, a first cutting element, and a second cutting element. The cannula of the cutting device includes an inner surface defining a passageway. The first cutting element extends from the distal end of the elongated shaft so as to contact tissue. The second cutting element also extends from the distal end of the elongated shaft. The second cutting element is configured for retractable extension beyond the distal end of the elongated shaft so as to contact tissue. The cutting device also includes a deployment mechanism disposed with the proximal end of the elongated shaft for actuating movement of the second cutting element.

Abstract: An ultrasonic medical instrument includes a probe shaft having a threaded coupling at a proximal end and an end effector or head at a distal end. The coupling is configured for operative attachment to a source of ultrasonic mechanical vibratory energy, while the head has an operative surface configured for engagement with organic tissues of a patient. The probe shaft, the coupling, and the head are made of a metal or metal alloy. At least one end-of-life indicator element is affixed to the probe shaft or head, the indicator element being made of a material that gradually disintegrates or degrades with use of the instrument so as to provide a visible indicator of degree of use and remaining useful life of the instrument.

Abstract: In one general aspect, various embodiments are directed to systems and methods for controlling a surgical instrument. The surgical instrument may comprise an ultrasonic transducer, a blade extending distally from the ultrasonic transducer along a longitudinal axis, and a motor coupled to the ultrasonic transducer. The motor, when activated, may rotate the ultrasonic transducer and the blade about the longitudinal axis. A control system may receive an indication to operate the surgical instrument according to an ultrasonic-only mode. The control system may instruct the motor to rotate the blade to a park position, and activate the ultrasonic transducer to longitudinally vibrate the blade.

Abstract: An angioplasty catheter comprises a catheter body having a balloon or other radially expandable shell at its distal end. An external structure is carried over the shell and scores a stenosed region in a blood vessel when the balloon is inflated therein. The catheter has an attachment structure disposed between the catheter body and the balloon to accommodate foreshortening and rotation of the external structure as the balloon is expanded. The external structure may be part of a helical cage structure which floats over the balloon. Stabilizing struts are provided between at least some of the helical struts.

Abstract: A treatment medical and medical device are disclosed for cutting a substance inside a body lumen. The medical device includes a drive shaft that is rotatable; a strut that is rotatably connected to a distal side of the drive shaft, that extends along a rotation axis, and whose central portion is expandable radially outward; and a support portion that is rotatably connected to the distal side of the drive shaft, that is formed in a mesh shape and a tubular shape while including multiple gaps, at least a portion of which is positioned on a radially inner side of the strut, and that is expandable radially outward by a central portion in a direction extending along the rotation axis being bent.

Abstract: A treatment method and medical device are disclosed for cutting a substance inside a body lumen. The medical device includes a drive shaft that is rotatable; a strut that is rotatably connected to a distal side of the drive shaft, that extends along a rotation axis, and whose central portion is expandable radially outward; and a support portion that is rotatably connected to the distal side of the drive shaft, that is formed in a mesh shape and a tubular shape while including multiple gaps, at least a portion of which is positioned on a radially inner side of the strut, and that is expandable radially outward by a central portion in a direction extending along the rotation axis being bent.

Abstract: A rotatable thrombectomy wire for breaking up thrombus or other obstructive material comprising an inner core composed of a flexible material and an outer wire surrounding at least a portion of the inner core. The outer wire has a sinuous shaped portion at a distal region. The inner core limits the compressibility of the outer wire. The outer wire is operatively connectable at a proximal end to a motor for rotating the wire to macerate thrombus.

Abstract: A hemostatic device is provided to stop bleeding at a puncture site on the wrist of a patient, the device comprising a transparent flexible band to be wrapped at the site where the bleeding is to be stopped, a curved frame having an inner peripheral side and possessing a first curved portion in its first half and a second curved portion in its second half, a first balloon provided on the inner peripheral side in the first half of the curved frame and a second balloon provided on the inner peripheral side in the second half of the curved frame. The bleeding from a first artery is stopped by compressing the first artery at the puncture site using inflation of the first balloon and the blood flow in the first artery is increased by compression of a second artery using inflation of the second balloon.

Abstract: The present disclosure provides a pressure-depending clutching device for locating and safely positioning a needle in a body cavity. The device is capable of automatically engaging and disengaging the needle from a driving force. The device has a body with an interior space, a pressure-sensing element and a force-receiving element. The pressure-sensing element, the force-receiving element, and the complementary force-sending element form a driving force engaging mechanism for coupling the force-applying structure to the needle during operation. Before the needle reaches the target body cavity, the pressure in the needle causes the clutching device to assume an “engaged” state. When the needle reaches the body cavity, the change in pressure causes the clutching device to assume a “disengaged” state, thereby, automatically positioning the needle in the cavity to avoid overshooting.

Abstract: Cannula anchor assemblies are disclosed which consist of a threaded cannula and a cannula anchor. The cannula anchor system allows for secure anchoring into the body wall, and proper cannula height adjustment prior to and during surgery. Sutures through the body wall may be secured to the cannula anchor either directly through the cannula anchor, or around suture posts attached therein. The cannula anchor also prevents excessive plunge of a trocar into the patient. The cannula anchor is generally configured with internal threads that mate with a threaded cannula.

Abstract: A surgical system including a surgical instrument and a protection device is included. The surgical system includes a surgical instrument having an extension assembly releasably coupled thereto. The extension assembly includes a trocar member disposed within a distal end of the extension assembly and the trocar member includes an engagement feature defined in an outer surface thereof. The protection device is releasably coupled to the engagement feature of the trocar member, thereby providing a barrier adjacent a tip of the trocar member. A method of sterilizing a surgical instrument is also provided.

Abstract: A method of embryo transfer (“ET”) that improves fertility rates by eliminating transferred air during the procedure is provided. Also provided is a method for hormonally enhancing the uterine wall of a patient either prior to or during the time of ET. Quantitative administration of transfer solutions is accomplished with a modified apparatus that provides for implantation of an embryo into the uterus of a patient. The apparatus comprises an outer sheath and an inner lumen arranged to be slidably disposed within the outer sheath. The inner lumen includes at least one visual marker situated on the exterior surface adjacent its distal end thereof.

Abstract: A fixation clamp for use in an external fixation system for holding bone fragments adjacent to each other with the help of fixation elements has at least one clamping assembly having a pair of jaws with at least two different size grooves to accommodate a bone fixation element such as a pin or rod. An alternate clamping assembly has at least three grooves wherein at least two of the grooves have a different size adapted to accommodate a correspondingly sized bone fixation element such as a bone pin. The longitudinal axes of the grooves define a polygon. The jaw pairs can be rotated about a central longitudinal axis to present different size reception cavities towards the pins or rocks depending on their diameter.