DCT
1:19-cv-01528
ConforMIS Inc v. Zimmer Biomet
I. Executive Summary and Procedural Information
- Parties & Counsel:
- Plaintiff: Conformis, Inc. (Delaware)
- Defendant: Medacta USA, Inc. (Delaware) and Medacta International SA (Switzerland)
- Plaintiff’s Counsel: Young Conaway Stargatt & Taylor LLP; Arnold & Porter Kaye Scholer LLP
- Case Identification: 1:19-cv-01528, D. Del., 10/14/2020
- Venue Allegations: Venue is alleged to be proper in the District of Delaware because Defendant Medacta USA is a Delaware corporation, and Defendant Medacta International is subject to jurisdiction through its business activities directed at the United States via its subsidiary.
- Core Dispute: Plaintiff alleges that Defendant’s patient-specific surgical instrument systems, MyKnee and MyShoulder, infringe four patents related to the use of patient imaging data to create custom surgical tools and guides for joint arthroplasty.
- Technical Context: The technology at issue concerns patient-specific orthopedic devices, where medical imaging like CT or MRI scans are used to create customized surgical instruments that match a patient's unique anatomy, aiming to improve implant fit and surgical accuracy.
- Key Procedural History: The filing is a Second Amended Complaint in an action that consolidates two separate cases. No prior litigation, licensing history, or post-grant patent office proceedings are mentioned in the complaint.
Case Timeline
| Date | Event |
|---|---|
| 2003-11-25 | Priority Date for ’129 & ’304 Patents |
| 2005-03-14 | Priority Date for ’161 Patent |
| 2008-06-09 | Priority Date for ’482 Patent |
| 2013-02-19 | ’129 Patent Issued |
| 2013-06-11 | ’304 Patent Issued |
| 2015-11-17 | ’161 Patent Issued |
| 2016-03-29 | ’482 Patent Issued |
| 2020-10-14 | Complaint Filing Date |
II. Technology and Patent(s)-in-Suit Analysis
U.S. Patent No. 8,377,129 - "Joint Arthroplasty Devices and Surgical Tools"
- Patent Identification: U.S. Patent No. 8,377,129, "Joint Arthroplasty Devices and Surgical Tools," Issued February 19, 2013.
The Invention Explained
- Problem Addressed: The patent describes that for decades, surgeons have used standard, one-size-fits-all instrument systems for joint replacement that are not designed with reference to individual patient anatomy, which can lead to imprecise implant placement and post-surgery complications like pain and loss of function (’129 Patent, col. 2:44-50; Compl. ¶16).
- The Patented Solution: The invention is a patient-specific surgical instrument system created from a patient's medical imaging data (e.g., MRI). The system features a surface designed to mate precisely with the patient's unique, uncut joint anatomy (including cartilage) and includes a guide for directing surgical tools like drills. This guide is positioned at a predetermined orientation relative to the patient's anatomical and biomechanical axes to ensure accurate cuts and implant placement (’129 Patent, Abstract, col. 61:15-32).
- Technical Importance: This technology represented a shift from the conventional paradigm of fitting the patient to the implant and tools, to one where the implant and tools are designed to fit the patient, with the goal of improving surgical reproducibility and accuracy (Compl. ¶¶17-18).
Key Claims at a Glance
- The complaint asserts at least independent claim 1 (Compl. ¶37).
- Claim 1 requires:
- A patient-specific instrument system for knee surgery.
- A patient-specific surface for engaging a substantially uncut portion of the knee joint, where the surface includes cartilage information derived from image data.
- A guide for directing a surgical instrument that defines a drilling path.
- The guide has a predetermined position and orientation relative to the patient-specific surface and at least one of an anatomical or biomechanical axis.
- The drilling path’s position is based on a predetermined rotation angle of an orthopedic implant.
U.S. Patent No. 8,460,304 - "Joint Arthroplasty Devices and Surgical Tools"
- Patent Identification: U.S. Patent No. 8,460,304, "Joint Arthroplasty Devices and Surgical Tools," Issued June 11, 2013.
The Invention Explained
- Problem Addressed: The patent addresses the same technical problem of imprecision in joint repair surgery resulting from the use of non-patient-specific tools (’304 Patent, col. 2:44-50).
- The Patented Solution: The invention is a surgical instrument in the form of a "mold" with an internal surface that includes joint information derived from a patient's image data, allowing it to conform to the patient's specific anatomy. The mold includes two or more guide holes for surgical pins, with the position of at least one hole being based on anatomical information and a predetermined rotation angle for the final implant. This allows the mold to precisely orient surgical pins, which then guide subsequent surgical steps (’304 Patent, Abstract, col. 61:12-25).
- Technical Importance: The invention provides a custom-fitted guide that simplifies the surgical technique by accurately locating the initial pin placements, which are critical for achieving the correct alignment and rotation of the final implant (Compl. ¶18).
Key Claims at a Glance
- The complaint asserts at least independent claim 1 (Compl. ¶51).
- Claim 1 requires:
- A surgical instrument comprising a mold with an internal surface derived from patient image data.
- Two or more guide holes configured to guide a surgical pin.
- At least one guide hole has a position based on anatomical information of the joint to facilitate placement of an articular repair system.
- The articular repair system has a predetermined rotation angle, and the guide hole's position is based on that angle.
U.S. Patent No. 9,186,161 - "Surgical Tools for Arthroplasty"
- Patent Identification: U.S. Patent No. 9,186,161, "Surgical Tools for Arthroplasty," Issued November 17, 2015.
- Technology Synopsis: The patent claims a surgical system that includes both an articular repair system (implant) and a patient-specific surgical instrument. The instrument is a mold created from image data of the patient's joint and includes guide holes whose position and/or orientation is based on anatomical information and a predetermined rotation angle of the implant it is designed to place.
- Asserted Claims: Independent claim 1 (Compl. ¶71).
- Accused Features: The MyKnee and MyShoulder products are accused of being surgical systems that use patient-specific guides created from CT/MRI data to position an implant according to pre-planned parameters, including rotation angles (Compl. ¶¶72-79).
U.S. Patent No. 9,295,482 - "Patient Selectable Joint Arthroplasty Devices and Surgical Tools"
- Patent Identification: U.S. Patent No. 9,295,482, "Patient Selectable Joint Arthroplasty Devices and Surgical Tools," Issued March 29, 2016.
- Technology Synopsis: The patent claims a joint arthroplasty system comprising an implant and a patient-specific block. The block's patient-contacting surface is configured to have a shape that is a "substantially a negative" of both the subchondral bone surface and the cortical bone surface of the joint. The surface is also configured to reference an osteophyte (bone spur), ensuring a precise and stable fit for guiding surgical tools.
- Asserted Claims: Independent claim 13 (Compl. ¶91).
- Accused Features: The MyKnee system is accused of being a system that includes an implant and a patient-specific cutting block created from a 3D bone model. The complaint alleges this block is designed to fit the patient's bone morphology and references osteophytes, which surgeons are specifically instructed not to remove (Compl. ¶¶92-94).
III. The Accused Instrumentality
Product Identification
- The accused instrumentalities are Medacta’s MyKnee® System and MyShoulder instrument system (Compl. ¶¶27, 30).
Functionality and Market Context
- The MyKnee system consists of "patient-specific" instruments for knee replacement surgery that are "based on CT or MRI images of the patient's knee" (Compl. ¶27). The instruments are described as being "designed for a single patient to assist in the positioning of total knee replacement components intraoperatively and in guiding the marking of bone before cutting" (Compl. ¶38). The system is fixed to the bone using "cortical pins" (Compl. ¶38). An illustrative image shows the MyKnee instrument being secured to a femur with surgical pins (Compl. p. 9).
- The MyShoulder system is described as providing "patient-specific instruments for shoulder surgery" (Compl. ¶30). The system allegedly allows a surgeon to "realize the pre-operative 3D planning and deliver accurate implant placement using CT based 3D printed cutting and pin guides" (Compl. ¶57). An image included from a promotional video depicts the MyShoulder instrument being used during live surgery (Compl. p. 17).
- The complaint alleges that Medacta’s instruments and products compete with Conformis’s own patient-specific surgical products (Compl. ¶32).
IV. Analysis of Infringement Allegations
’129 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A patient-specific instrument system for surgery of a diseased or damaged knee joint of a patient... | The MyKnee® system is a "patient-specific" instrument designed for a single patient for knee replacement surgery. | ¶38 | col. 61:15-18 |
| ...a patient-specific surface for engaging at least a portion of a substantially uncut joint surface...the patient-specific surface including cartilage information derived from image data... | The MyKnee® instrument is based on CT or MRI images and is designed to position components "before cutting." Its contact area is based on this imaging. | ¶¶38, 39 | col. 61:19-25 |
| ...a guide for directing a surgical instrument...wherein the guide defines a drilling path through at least a portion of the knee joint... | The MyKnee® instrument is fixed using "cortical pins," and the surgeon inserts a pin into a hole to fix the rotation. | ¶¶38, 39 | col. 61:26-30 |
| ...wherein the guide has a predetermined position...and a predetermined orientation relative to...an anatomical axis [or] a biomechanical axis... | A surgeon plans "parameters regarding femoral and tibial implantation" pre-operatively, which include "angles." | ¶39 | col. 61:27-29 |
| ...the drilling path having a position based on a predetermined internal rotation angle or external rotation angle of an orthopedic implant. | The surgeon plans "femoral rotation" pre-operatively and can fix the selected rotation by "inserting a pin in the central hole." | ¶39 | col. 61:30-32 |
- Identified Points of Contention:
- Scope Questions: A central question may be whether deriving an instrument shape from an MRI scan inherently satisfies the "including cartilage information" limitation. The complaint alleges this connection, but the defense may argue that the system primarily models bone geometry and does not distinctly use cartilage data to define the patient-specific surface.
- Technical Questions: The analysis may turn on the evidence linking the "drilling path" for the fixation pins to the "predetermined...rotation angle of an orthopedic implant." The complaint suggests a connection via pre-operative planning, but it raises the question of whether the pin locations are functionally determined by the rotation angle or by other factors, such as achieving a stable fit on the bone. An illustrative image shows the contact area for the MyKnee cutting block on the distal condyles, which is determined from CT and MRI imaging (Compl. p. 10).
’304 Patent Infringement Allegations
| Claim Element (from Independent Claim 1) | Alleged Infringing Functionality | Complaint Citation | Patent Citation |
|---|---|---|---|
| A surgical instrument for use in surgically repairing a joint of a patient, the surgical instrument comprising: a mold having an internal surface that includes joint information derived from image data... | The MyKnee® instrument is a "patient-specific" instrument based on CT or MRI images of the patient's knee. The MyShoulder instrument relies on CT images of the patient's shoulder. | ¶¶52, 58 | col. 61:12-17 |
| ...and two or more guide holes, each configured to guide a surgical pin... | The MyKnee® instrument is fixed using "cortical pins." The MyShoulder instrument has "two or more guide holes, each of which is configured to guide a surgical pin." | ¶¶53, 59 | col. 61:18-19 |
| ...wherein at least one of the two or more guide holes has a position based on anatomical information of the joint...to facilitate the placement of an articular repair system... | The MyKnee® guide instructs operators to verify that the points of contact are "respected," linking the instrument's position to the patient's anatomy to ensure stability for placing the repair system. | ¶54 | col. 61:20-24 |
| ...wherein the articular repair system has a predetermined rotation angle and wherein the position is based on the predetermined rotation angle. | For MyKnee®, surgeons plan "femoral rotation" pre-operatively and can fix this rotation by inserting a pin. For MyShoulder®, pre-operative planning includes virtually positioning the implant. | ¶¶55, 59 | col. 61:24-25 |
- Identified Points of Contention:
- Scope Questions: The construction of the term "mold" may be a central issue. The defense might argue that the accused cutting blocks, which primarily guide tools, do not function as a "mold" in the manner described by the patent.
- Technical Questions: It raises the question of whether the "position" of the guide holes is directly "based on" the predetermined rotation angle. The defense may contend that the hole positions are determined by the need to secure the instrument to the bone surface, and that rotation is a separate parameter achieved using the secured guide, not a factor that dictates the guide's physical design.
V. Key Claim Terms for Construction
’129 Patent
- The Term: "patient-specific surface including cartilage information"
- Context and Importance: This term is critical because it defines the primary interface between the patented instrument and the patient. The scope of the claim depends on whether simply using an imaging modality that can see cartilage (like MRI) is sufficient, or if the system must actively process and use that cartilage data to define the surface.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The specification discusses using imaging techniques to create a "negative" of the articular surface, which could suggest that any surface derived from a comprehensive patient scan meets the "patient-specific" requirement (’129 Patent, col. 40:45-50).
- Evidence for a Narrower Interpretation: The claim explicitly requires "cartilage information." The specification emphasizes creating a system that achieves a "near anatomic fit with the surrounding structures and tissues," including cartilage, suggesting that the surface must conform to the cartilage topography, not just the underlying bone (’129 Patent, col. 5:15-20).
’304 Patent
- The Term: "position is based on the predetermined rotation angle"
- Context and Importance: This phrase links the physical design of the instrument (the location of the guide holes) to the surgical plan (the implant's rotation). Infringement will likely depend on whether the guide hole's location is functionally dictated by the rotation angle or merely accommodates it.
- Intrinsic Evidence for Interpretation:
- Evidence for a Broader Interpretation: The patent's focus on achieving proper alignment through pre-planning could support an interpretation where any guide designed to facilitate a pre-planned rotation satisfies the "based on" requirement (’304 Patent, col. 43:30-40).
- Evidence for a Narrower Interpretation: The claim language links the "position" of the hole to the "rotation angle." Practitioners may focus on this term because it suggests a direct causal link. A defendant may argue this requires a direct algorithmic input, where the rotation angle is a variable used to calculate the coordinates of the guide holes, not just a general surgical objective.
VI. Other Allegations
- Indirect Infringement: The complaint alleges both induced and contributory infringement for all four patents-in-suit. Inducement is primarily based on allegations that Medacta provides the accused systems along with instructional materials, such as "surgical technique guides," "product manuals," and promotional videos, that allegedly instruct and encourage surgeons to use the products in an infringing manner (Compl. ¶¶41-42, 61-62, 81-82, 97-98).
- Willful Infringement: Willfulness is alleged for all four patents. The complaint bases this allegation on Medacta having had knowledge of the patents and its alleged infringement "at least as early as the filing of the original Complaint (or soon thereafter)" (Compl. ¶¶45-46, 65-66, 85-86, 101-102).
VII. Analyst’s Conclusion: Key Questions for the Case
- A core issue will be one of evidentiary proof: can Conformis demonstrate that Medacta's systems, which are derived from MRI/CT scans, specifically incorporate and use "cartilage information" to define the instrument's patient-contacting surface, as required by claims of the ’129 Patent, or do they primarily rely on bone geometry?
- A key question of functional linkage will be central to the dispute: does the "position" of the guide holes in the accused instruments result directly from being "based on" the pre-planned "predetermined rotation angle" of the implant, or are the hole positions dictated by other constraints, such as achieving a stable anatomical fit, with the planned rotation being a separate parameter achieved through the use of the instrument?
- The case may also involve a definitional dispute over claim scope: can the term "mold," as used in the ’304 and ’161 patents in the context of forming an implant, be construed to cover the accused MyKnee and MyShoulder cutting and pinning guides, which are used to prepare the bone surface?