DCT
2:15-cv-02873
Rama E Chandran v. Smith Nephew Inc
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Rama E. Chandran, M.D. (California)
- Defendant: Smith & Nephew, Inc. (Delaware)
- Plaintiff’s Counsel: Apogee Law Group; Schwabe, Williamson & Wyatt, P.C.
- Case Identification: 2:15-cv-02873, C.D. Cal., 04/17/2015
- Venue Allegations: Venue is based on Defendant's alleged continuous and systematic business in the district, designation of an agent for service of process in California, and offers to sell, sales, and inducement of use of the accused product within the judicial district.
- Core Dispute: Plaintiff alleges that Defendant’s Trigen® Hindfoot Fusion Nail, an orthopedic implant system, infringes a patent related to an intramedullary rod and oblique screw assembly for ankle arthrodesis.
- Technical Context: The technology concerns orthopedic implants for tibio-calcaneal arthrodesis, a surgical procedure to fuse the tibia and calcaneus bones, often as a "salvage" procedure for patients with severe ankle trauma, disease, or a degraded talus bone.
- Key Procedural History: The complaint alleges that Plaintiff provided Defendant with actual notice of the patent-in-suit and its alleged application to the accused product in July 2013, approximately 21 months prior to filing the complaint. This notification is cited as a basis for willfulness.
Case Timeline
| Date | Event |
|---|---|
| 2000-08-02 | ’293 Patent Priority Date |
| 2003-06-17 | ’293 Patent Issue Date |
| 2013-07-01 | Plaintiff allegedly notified Defendant of infringement |
| 2015-04-17 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 6,579,293 - INTRAMEDULLARY ROD WITH INTERLOCKING OBLIQUE SCREW FOR TIBIO-CALCANEAL ARTHRODESIS, Issued June 17, 2003
The Invention Explained
- Problem Addressed: The patent's background section identifies problems with prior art ankle fusion devices, noting that some patients suffered from "relative motion between the supposedly affixed tibial and calcaneal bones," which could lead to substantial pain, instability, and additional joint damage (’293 Patent, col. 3:25-34). Prior art designs are characterized as using a vertical rod and a roughly horizontal pin, creating an obtuse angle between the components (’293 Patent, col. 2:41-54, Fig. 1).
- The Patented Solution: The invention is a surgical assembly comprising a vertical intramedullary rod and an "oblique screw" positioned at an acute angle relative to the rod (’293 Patent, Abstract; col. 4:4-7). This oblique screw is inserted through the calcaneus (heel bone), passes through a slanted hole in the vertical rod, and its threaded tip engages the lower end of the tibia (shin bone) (’293 Patent, col. 4:7-10). When tightened, the screw is designed to pull the tibia downward, creating compression against the calcaneus, which is asserted to improve the stability of the fusion (’293 Patent, col. 4:10-13; Fig. 2).
- Technical Importance: The use of an acute-angled screw to achieve direct compression between the tibia and calcaneus was presented as a method to provide "greater stability and better performance" compared to prior art devices, particularly for patients with severe ankle problems where the talus bone is degraded (’293 Patent, col. 4:60-63).
Key Claims at a Glance
- The complaint asserts independent claims 1 (a surgical kit) and 6 (a surgical device), as well as method claim 10 (Compl. ¶¶ 16, 22, 32).
- Independent Claim 1 (Surgical Implant Kit): Its essential elements are:
- A tibio-calcaneal rod with an oblique hole passing through its shaft.
- A screw with a threaded tip region, sized to pass through the rod's oblique hole.
- The rod and screw are designed to fit together inside an ankle joint.
- The oblique hole passes through the rod's shaft at "an angle."
- The screw's threaded tip allows it to establish "compression of the tibial bone against the calcaneal bone" when rotated.
- Independent Claim 6 (Surgical Implant Device): Its essential elements are:
- A screw with a base, shaft, and threaded tip region.
- The threaded tip is sized and suited to enter the lower end of a tibial bone and establish "compression of the tibial bone against the calcaneal bone" when rotated.
- The screw is packaged and labeled as a medical device for ankle arthrodesis.
- The complaint states that Plaintiff's infringement allegations are not limited to the enumerated claims (Compl. ¶ 16).
III. The Accused Instrumentality
Product Identification
- The accused product is the Smith & Nephew Trigen® Hindfoot Fusion Nail, also referred to as the "Trigen Nail" (Compl. ¶¶ 3, 11).
Functionality and Market Context
- The complaint alleges the Trigen Nail is an intramedullary nail system that includes an "oblique screw" and is used to perform tibio-calcaneal arthrodesis (Compl. ¶¶ 10-11). The system is allegedly used to achieve fusion by "compressing the tibia bone directly or indirectly against the calcaneal bone" (Compl. ¶ 9). The complaint provides an x-ray image described as showing an implanted Trigen Nail, which depicts a large intramedullary nail with several interlocking screws, including one oriented at an oblique angle relative to the nail (Compl. p. 7). The complaint alleges the Trigen Nail is marketed for "salvage" procedures in patients with conditions like avascular necrosis or severe arthritis, where the talus bone lacks integrity (Compl. ¶¶ 10, 25).
IV. Analysis of Infringement Allegations
’293 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| a. at least one tibio-calcaneal rod having a tip, a shaft, and a base... and having an oblique hole passing through the shaft... | The Trigen® Hindfoot Fusion Nail is an intramedullary nail (rod) that is alleged to be used with an oblique screw, which implies the nail has a corresponding oblique hole. | ¶¶ 9, 11 | col. 6:40-44 |
| b. at least one screw having a base, a shaft, and a threaded tip region, said threaded tip region being small enough to pass through the oblique hole... | The Trigen Nail system includes an "oblique screw" designed to interlock with the intramedullary nail. The complaint includes a visual depicting the alleged implanted device with this screw. | ¶¶ 11, 25; p. 7 | col. 6:45-49 |
| wherein the oblique hole passes through the shaft of the rod at an angle with respect to the shaft... | The Trigen Nail's oblique screw is alleged to be positioned at an angle relative to the main nail, as depicted in the provided x-ray image. | ¶¶ 11, 25; p. 7 | col. 11:49-51 |
| and wherein the rod and screw are designed to fit together inside an ankle joint, thereby establishing an ankle arthrodesis assembly... | The Trigen Nail is marketed and sold for establishing ankle arthrodesis by fusing the ankle joint. A diagram shows the intended placement of the claimed assembly within an ankle. | ¶¶ 11, 19; p. 4 | col. 11:52-54 |
| and wherein the threaded tip region of the screw allows the screw to establish compression of the tibial bone against the calcaneal bone... | The complaint alleges the Trigen Nail functions by "compressing the tibia bone against the calcaneal bone." It further alleges that for certain patients, this requires the oblique screw to penetrate the tibia. | ¶¶ 9, 11, 25 | col. 11:55-59 |
Identified Points of Contention
- Scope Questions: The patent specification distinguishes the invention's "acute angle" from the "obtuse angle" of the prior art (’293 Patent, col. 7:25-30). A central question of claim construction will be whether the claim term "an angle" is limited to the acute angle described as a key feature in the specification. The infringement analysis will depend on the angle of the screw in the accused Trigen Nail.
- Technical Questions: A key factual dispute may arise over whether the Trigen Nail's oblique screw performs the functions required by the claims. This raises the question of what evidence demonstrates that the screw's tip region (i) enters the lower end of the tibial bone and (ii) establishes the claimed "compression" of the tibia against the calcaneus when implanted as instructed by the Defendant. The complaint's x-ray image is offered as evidence supporting this theory (Compl. ¶ 25, p. 7).
V. Key Claim Terms for Construction
The Term: "an angle" (Claim 1)
- Context and Importance: The patent's primary asserted point of novelty over prior art is the use of an acute angle between the rod and screw, as opposed to a prior art obtuse angle. The construction of "an angle"—whether it is limited to acute angles or can encompass any non-parallel orientation—will be critical to determining the scope of the claim and, consequently, infringement.
- Intrinsic Evidence for a Broader Interpretation: The plain language of claim 1 recites "an angle" without an explicit "acute" limitation.
- Intrinsic Evidence for a Narrower Interpretation: The specification repeatedly emphasizes an "acute angle" as the inventive concept, stating it "provides greater stability and better performance" (’293 Patent, col. 4:60-63). The Summary of the Invention describes the screw as being "positioned at an acute angle" (’293 Patent, col. 4:5-6), and the figures distinguish the invention's angle (aINV) from the prior art's angle (aPA) (’293 Patent, Figs. 1-2). This could support an argument that the patentee defined the invention as being limited to an acute angle.
The Term: "compression of the tibial bone against the calcaneal bone" (Claims 1, 6)
- Context and Importance: This functional language defines a key result of the claimed invention. Practitioners may focus on this term because the infringement analysis will depend on whether the accused device is proven to achieve this specific compressive function, as opposed to merely providing fixation through other means.
- Intrinsic Evidence for a Broader Interpretation: The term itself does not specify a degree or mechanism of compression, potentially allowing it to cover any configuration where the tibia and calcaneus are brought into contact under some force.
- Intrinsic Evidence for a Narrower Interpretation: The specification describes this compression as an active result of tightening the screw, which "pull[s] the tibia bone in a downward direction" to make the fixation "more secure" (’293 Patent, col. 7:24-28). This suggests the compression must be a direct, intended, and significant functional result of rotating the screw, not merely incidental contact.
VI. Other Allegations
Indirect Infringement
- Contributory (Count II): The complaint alleges that the Trigen Nail is a material component specially designed for infringement and has no substantial non-infringing use (Compl. ¶¶ 23, 25). It supports this by claiming that for patients with a normal talus, an intramedullary nail is "contraindicated" and its use is not "good medical practice," thereby limiting its appropriate use to scenarios that allegedly require infringement (Compl. p. 7:26-p. 8:4).
- Inducement (Count III): The complaint alleges inducement based on Defendant's marketing materials, including "published medical brochures and other sales literature," which allegedly instruct surgeons to use the Trigen Nail in an infringing manner (Compl. ¶ 33). It further alleges that Defendant's sales representatives "knowingly assist" surgeons in the operating room, providing a basis for actual knowledge of the infringing acts (Compl. ¶ 33).
Willful Infringement
- Willfulness is alleged based on Defendant’s purported actual knowledge of the ’293 patent since at least July 2013, following a notice letter from the Plaintiff (Compl. ¶¶ 14, 24). The complaint also alleges, upon information and belief, that Defendant knew of the patent "at or prior to the first manufacture, marketing, and sale of the Trigen® Nail" (Compl. ¶ 24).
VII. Analyst’s Conclusion: Key Questions for the Case
The resolution of this dispute will likely depend on the court's determination of the following central questions:
- A core issue will be one of claim construction: is the claim term "an angle," as used in Claim 1, limited by the patent's specification to the "acute angle" that the inventor described as the point of departure from prior art, or does the plain language permit a broader interpretation?
- A key evidentiary question will be one of functional operation: does the accused Trigen® Nail, when used as instructed for its indicated patient population, necessarily function by having its oblique screw penetrate the tibia to create the specific "compression of the tibial bone against the calcaneal bone" as required by the claims, or does it achieve fixation through a different technical mechanism?