Obviousness

Obviousness Analysis of US Patent 12303166 under 35 U.S.C. § 103

This analysis assesses the obviousness of US Patent 12303166 ("Methods for accessing nerves within bone") under 35 U.S.C. § 103, based on the provided "Prior art" section and the described "inventive embodiments" (acting as proxies for claims). A person having ordinary skill in the art (PHOSITA) in this field would likely be a medical device engineer or a surgeon experienced in minimally invasive spinal or orthopedic procedures. This PHOSITA would be familiar with spinal anatomy, challenges in navigating instruments through bone (including cancellous bone with varying densities), properties of materials like Nitinol and PEEK, standard steerable instrument design principles, nerve ablation techniques, and the need for precise surgical delivery.

The core inventive concepts of US12303166, as outlined in the "inventive embodiments," include:

• A system for channeling a predictable, curved path into bone using a trocar and a curved cannula (Embodiment 1).
• A method for using this system, including the subsequent creation of a straight channel for a treatment device (Embodiment 10).
• A kit providing cannulas with varying preformed curvatures (Another Aspect).
• Specific components like straightening stylets, curved stylets (with angled tips for maintaining curvature and piercing bone), and straight channeling stylets that deform to navigate curves but retain a straight form upon exiting.

Combinations of Prior Art References and Motivation to Combine

Several combinations of the identified prior art, along with general knowledge in the field, would likely render the key aspects of US12303166 obvious to a PHOSITA.

1. WO2008039234A2 (Pellegrino et al.) in combination with general knowledge of steerable instrument design, material science, and surgical needs.

• WO2008039234A2 ("System and method for creating a steered path in bone"), published April 3, 2008: This document, by the same inventors as US12303166 and published before US12303166's priority date of September 26, 2008, directly teaches a "system and method for creating a steered path in bone," specifically for accessing nerves within the spine using an introducer (trocar) and a steerable instrument (stylet or cannula). This reference squarely addresses the fundamental concept of creating a non-linear path in bone to reach an anatomical target, thereby making broad aspects of US12303166's Embodiments 1 and 10 obvious.

• Motivation to combine with general knowledge:

  • Predictable Curved Path: The background of US12303166 explicitly notes the difficulty of navigating a probe in bone and ensuring precise positioning due to "varying densities of bone." Given WO2008039234A2's objective of creating a "steered path" for precise nerve access, a PHOSITA would be highly motivated to make this steering predictable and less susceptible to variations in bone density. The use of a pre-formed curved cannula made of a shape-memory material (e.g., Nitinol, as discussed in US12303166) that is straightened by an outer rigid trocar during insertion and then allowed to regain its preformed curve upon exiting is a well-known engineering principle in medical device design for creating predictable, controlled curves in steerable instruments. This would render the "deflectable tip with a preformed curve such that the tip straightens while being delivered through the trocar and regains its preformed curve upon exiting" obvious.
  • Straight Channel after the Curve: Many therapeutic devices, such as the RF probes mentioned in US12303166, typically have straight active elements that require stable, linear access for precise energy delivery. A PHOSITA, having used the principles from WO2008039234A2 to create a curved path to reach a target area, would be motivated to ensure a stable, linear final approach for accurate placement and activation of such a treatment device. Creating a distinct "straight channeling stylet" (as described in US12303166) that is flexible enough to navigate the curved cannula but rigid enough (e.g., made of PEEK, as specified in US12303166) to create a linear working channel in cancellous bone upon exiting is a logical engineering solution to achieve this precise terminal access.
  • Kit with Varying Curvatures: The need to accommodate varying patient anatomies and different target locations (e.g., BVN in lumbar versus cervical vertebrae) is a well-understood clinical reality, as even acknowledged by US12303166. A PHOSITA, aiming to provide a versatile and commercially viable surgical solution based on WO2008039234A2's steered path, would find it obvious to offer a kit containing instruments with a range of preformed curvatures (varying radii, angles, and lengths) to match diverse anatomical requirements and surgical approaches. This is a standard practice in the medical device industry for customization.

• Conclusion for Combination 1: This combination renders obvious the systems and methods for creating a predictable curved path in bone, the creation of a subsequent straight channel, and the provision of a kit with varying curvatures, as described in US12303166's inventive embodiments.

2. Combination 1 + US6699242B1 (Treat) or US20080183204A1 (Davenport et al.)

• WO2008039234A2 (Pellegrino et al.): As established, this teaches accessing nerves within bone via a steered path.

• US6699242B1 ("Tissue ablation system and methods"), issued March 4, 2003: This patent describes systems and methods for tissue ablation, often using radiofrequency (RF) energy. US12303166 itself cites this patent in its detailed description regarding the ablation of tissue.

• US20080183204A1 ("Radiofrequency ablation catheter with fluid cooled active electrode"), published August 7, 2008: This document, published before US12303166's priority date, details an RF ablation catheter, specifically featuring a fluid-cooled active electrode for temperature control during ablation.

• Motivation to combine: A PHOSITA, having a system and method for precisely accessing intraosseous nerves (from WO2008039234A2), would be strongly motivated to combine this access technology with a known and effective means of treating those nerves. Both US6699242B1 and US20080183204A1 provide details on RF ablation, a common and effective modality for nerve treatment. The ultimate goal of accessing the basivertebral nerve (BVN) in US12303166 is therapeutic treatment, often ablation or denervation. Therefore, combining the access methodology with an ablation device and method is a straightforward and desirable integration to achieve a functional medical procedure. This combination would render obvious the delivery of a treatment device, such as an RF probe, through the channeled path to denervate the BVN, as described in US12303166.

3. Kopecky et al. (Side-exiting coaxial needle) in combination with WO2008039234A2 and general knowledge.

• Kopecky et al. (1996) ("Side-Exiting Coaxial Needle for Aspiration Biopsy"): This paper describes a system where a smaller needle is deflected by a ramp inside a guide needle to exit through a side hole.

• WO2008039234A2 (Pellegrino et al.): Teaches creating a steered path in bone.

• Motivation to combine: While US12303166 distinguishes itself from Kopecky by emphasizing predictable linear exit and navigation, the general concept of deflecting an inner instrument from a main guide to achieve non-linear access is present in Kopecky. A PHOSITA seeking to implement a "steered path" as taught by WO2008039234A2 might consider various mechanisms for steering or deflecting instruments. Kopecky presents one such mechanism for achieving non-linear access. Although Kopecky's specific mechanism might lack the desired predictability in bone, the underlying idea of using an inner, deflectable element in a coaxial system to create a non-linear path is a known starting point that a PHOSITA would improve upon with known engineering solutions (e.g., Nitinol properties, specific stylet designs) to address the predictability issues. This could lead to the concept of a deflectable tip cannula in WO'234, where the deflection is controlled and predictable.

Additional Considerations for Other Prior Art by Same Inventors

The other "Pellegrino et al." prior art documents (US20080275460A1, US20090099566A1, US20090259220A1, US20100087823A1), while having publication dates later than the priority date of US12303166, explicitly address very similar subject matter (steered paths in bone, radiofrequency nerve ablation, intraosseous nerve ablation systems, steerable stylet assemblies) and share the same inventors. If their effective filing dates precede September 26, 2008, they would also constitute prior art. In such a scenario, these documents would further reinforce the obviousness arguments by providing even more specific teachings of the components (e.g., steerable stylets, RF probes for nerve ablation) and methods that US12303166 claims, making their combination with WO2008039234A2 and general knowledge even more compelling to a PHOSITA, as they represent a natural evolution or related work by the same inventive entity.