Patent ID: 12251142

DESCRIPTION OF THE PREFERRED EMBODIMENT

Illustrative embodiments of the invention are described below. In the interest of clarity, not all features of an actual implementation are described in this specification. It will of course be appreciated that in development of any such actual embodiment, numerous implantation-specific decisions must be made to achieve the developers' specific goals such as compliance with system-related and business-related constraints, which will vary from one implementation to another. Moreover, it will be appreciated that such a development effort might be complex and time-consuming, but would nevertheless be a routine undertaking for those of ordinary skill in the art having the benefit of this disclosure. The systems and methods disclosed herein boast a variety of inventive features and components that warrant patent protection, both individually and in combination.

The digitizer pointer10of the present disclosure is configured to be used as part of a surgical rod bending system, for example the surgical rod bending systems shown and described in commonly-owned U.S. Pat. No. 8,539,888, issued Oct. 8, 2013 and entitled “System and Device for Designing and Forming a Surgical Implant,” and commonly-owned and co-pending U.S. patent application Ser. No. 13/815,643, filed Mar. 12, 2013 and entitled “System and Method for Performing Spinal Surgery,” the entire contents of each of which are hereby incorporated by reference into this disclosure as if set forth fully herein. More specifically, digitizer pointer comprises a part of a spatial tracking system used to obtain the location of one or more surgical implants during a surgical procedure. In addition to the spatial tracking system, the surgical bending systems described in the '888 patent and '643 application also include a control unit containing software to convert the implant locations to a series of bend instructions, and a mechanical rod bender to receive the bend instructions and effect precise bends in the rod. In addition to the adjustable offset feature previously disclosed (and incorporated by reference into this disclosure), the digitizer pointer10of the present disclosure includes a swivel feature that allows the distal end and the proximal end to swivel relative to one another and a translation feature that allows the distal end to mate with any number of instrumentation types in any number of surgical procedures.

Generally, the spatial tracking system includes an IR sensor, a digitizer pointer, as well as other components including Host USB converter. The spatial tracking system is in communication with control unit. The control unit has spatial relation software and is communicatively linked to the display so that information relevant to the surgical procedure may be conveyed to the user in a meaningful manner. By way of example, the relevant information includes, but is not limited to, spatial positioning data acquired by the IR sensor (e.g., translational data in the x, y, and z axes and orientation/rotational data Rx, Ry, and Rz). A neuromonitoring system may be communicatively linked to the spatial tracking system via the control unit. By way of example only, the neuromonitoring system may be the neuromonitoring system shown and described in U.S. Pat. No. 8,255,045, entitled “Neurophysiologic Monitoring System” and filed on Apr. 3, 2008, the entire contents of which are hereby incorporated by reference as if set forth fully herein. Once the user has digitized the implant locations and selected the desired rod solution, the user then executes the bends using a mechanical rod bender.

FIGS.1-3illustrate an example of a digitizer pointer10according to one implementation. The digitizer pointer10may be an all-in-one combination digitizer pointer for so-called “open” spine surgeries. By way of example, the digitizer pointer10includes a proximal portion12, a middle portion14, and a distal portion16. By way of example, the proximal portion12, middle portion14, and distal portion16comprise separate pieces that are assembled to form a single generally cylindrical elongated instrument. The proximal portion12includes an elongate tubular member18and an inner piston20. The inner piston20includes a threaded post22at the proximal end for mating with additional tracking instrumentation, for example an IR-reflective tracking array such as one shown and described in the above-referenced '643 application (incorporated by reference). The elongate tubular member18and inner piston20comprise the adjustable offset feature component of the digitizer pointer10. The adjustable offset feature allows the surgeon to add correction in the sagittal plane, and specific elements germane to the adjustable offset feature component are identical in form and function to the corresponding elements shown and described in the above-referenced '643 application (incorporated by reference) and will not be repeated here.

The swivel feature will now be described in more detail. In the example shown and described herein, the swivel feature includes several elements positioned on the distal end24of the elongated tubular member18working in concert with several elements positioned on the proximal end26of the middle portion14. The distal end24of the elongate tubular member18comprises a smooth cylindrical post28. A circumferential recess30is formed within the cylindrical post28, and a raised lip32is positioned at the proximal end of the cylindrical post28. The proximal end26of the middle portion14comprises a swivel housing34including a cylindrical cavity36sized and configured to receive the cylindrical post28therein. Retention pins38extend through pin apertures40in the swivel housing34and into the cavity36. Upon assembly, the retention pins38occupy space in the circumferential recess30, and allow for rotational (swivel) movement of the cylindrical post28while ensuring the cylindrical post28remains within the cavity36. The raised lip32interfaces with the rim of the cavity36to form a swivel interface location.

By way of example, the swivel feature may be desireable, according to surgeon preference to re-orient a screw-tulip to align with the other screws (and eventual rod) within a construct. For example, after the digitizer pointer10is engaged with a spinal implant (e.g bone screw), the user may manually hold the distal portion of the digitizer pointer10(e.g. any suitable place distal of the swivel interface) and swivel the proximal portion of the digitizer pointer10(e.g. any suitable place proximal of the swivel interface) about the swivel feature. The proximal portion of the digital pointer10is then rotated until the IR array (attached to the threaded post22) comes in view of the camera.

The translation feature will now be described in more detail. In the example shown and described herein, the translation feature includes several elements positioned on the middle portion14working in concert with several elements positioned on the distal portion16. In addition to the swivel housing34previously described, the middle portion14includes a elongate shaft42extending distally from the swivel housing34. The elongate shaft42includes a proximal segment44and a distal segment46. By way of example, the proximal segment44may have a different width dimension (e.g. diameter) than the distal segment46. In the example shown and described herein, the proximal segment44has a width diameter that is greater than the width dimension of the distal segment46. The proximal segment44has a smooth surface to facilitate translation of the distal portion16, as will be explained below. The proximal segment44further has a guide pin48extending laterally away from the smooth surface positioned approximately in the middle of the proximal segment44. The guide pin48is received within the shaped track62to help control translation of the distal portion16, as will be explained. The distal segment46extends distally from the proximal segment44and includes a hex lobe attachment feature50positioned at the distal end. The hex lobe attachment feature50is configured to engage a spinal implant, for example a bone screw head (not shown). A spring52is positioned about the proximal segment46and is configured to exert a force on the distal portion16to bias the distal portion16in an extended position (in which the hex lobe attachment feature50is positioned within the fork member58.

The distal portion16comprises an outer sleeve54having a track housing56at the proximal end, a fork member58at the distal end, and an interior lumen60extending through the entire length of the distal portion16. The interior lumen60is sized and configured to slideably receive the distal segment46of the middle portion14therein. The track housing56includes a shaped track62configured to receive the pin48therein. The track62may have any shape that facilitates self-locking, for example such the “C”-shape shown by way of example inFIGS.1-3. The track62has a first lock slot64positioned at the proximal end of the shaped track62and a second lock slot66positioned at the distal end of the shaped track62. The fork member58includes a pair of parallel extensions68having shaped ends70configured to engage a portion of a spinal implant, for example a tulip portion of a rod-receiving bone screw (not shown).

As previously mentioned, the spring52exerts a force on the distal portion16that biases the distal portion16in an extended position. In this position, the pin48is positioned within the first lock slot64at the proximal end of the shaped track62. A user may manually engage (e.g. grab) the track housing56and rotate the housing56such that the guide pin48is urged out of the first lock slot64, along the main portion of the shaped track62, and into the second lock slot66. As this happens, the distal portion16will be experience translation in a proximal direction. When the pin48is fully resting in the second lock slot66after translation, the hex lobe attachment feature50of the middle portion14will extend beyond the fork member58, as shown inFIG.3.

The translating feature allows the surgeon to perform two digitizing methods depending on the surgical procedure and the goals of the surgical procedure. In the first setting (in which the pin48is in the first lock slot64), the hex lobe attachment feature50is in a retracted position (since the distal portion16is extended), and the digitizer pointer10can digitize all open, fixed, and connector tulips via engagement between the implanted device and the fork member58. In the second setting (in which the pin48is in the second lock slot66), the hex lobe attachment feature50extends past the distal ends70of the fork member58, and the digitizer pointer10can digitize when there has been a lock screw placed. The hex lobe attachment feature50mates with a lock screw (not shown) and allows the surgeon to digitize the location of the temporary rod placement. Thus, the surgeon can digitize where the spine is during the temporary rod placement and when final rod bending is being achieved, for example during a pedicle subtraction osteotomy procedure.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown, by way of example only, in the drawings and are herein described in detail. It should be understood, however, that the description herein of specific embodiments is not intended to limit the invention to the particular forms disclosed. On the contrary, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined herein.