Arthrex prevails in patent dispute over wrist fracture device

In a win for medical device maker  Arthrex, a federal judge in Delaware has ruled that its wrist-plating system does not infringe a patent owned by competitor  TriMed Technologies.

The  decision was handed down on Monday, March 22, at the  US District Court for the District for Delaware. The dispute between the two companies arose when TriMed sued Arthrex in May 2018, alleging that its new system, the “volar hook plate” infringed US patent number 8,177,822.

The disputed ‘822 patent covers technology used to fix fractures of bones near the base of the hand. According to the  complaint, TriMed owns a number of patents directed to bone fixation technology and markets various plates designed for fixing fractures of different bones.

Issuance of claim construction order

In August 2018, Arthrex answered and filed declaratory judgment counterclaims for non-infringement and invalidity of the ’822 patent. After a briefing and hearing argument held on July 31, 2019, the court issued a claim construction order, which construed “wrap around a terminal endpoint of the bone” to mean “curving or extending onto the end surface of the bone”.

In April 2020, Arthrex filed a motion for summary judgment of non-infringement of the asserted claims of the ’822 patent, arguing that its accused volar hook plate does not “wrap around a terminal endpoint of the bone” because the “plate’s tines enter a surface that stops short of the distal radius’ end surface”.

According to Arthrex, under the court’s construction of the “wrap around” term, the “end surface of the bone” for the distal radius is the articular surface (which contains cartilage and forms the wrist joint).

In response, TriMed argued that Arthrex’s volar hook plate satisfies the “wrap around” term according to the court’s term construction “because the hook plate is designed to wrap around or extend to the end surface of the radius as defined by where the bone changes curvature from upward to downward”.

During an oral argument held in August, the court struggled to understand the parties’ interpretations of its construction and its application to the issue of infringement.

Invalidity counterclaim dismissed

Unable to determine whether there was an underlying dispute as to the meaning of the “wrap around” term or a factual dispute as to whether Arthrex’s volar hook plate met that limitation, District Judge Maryellen Noreika denied the motion for summary judgment in an oral ruling.

In denying Arthrex’s motion, the court emphasised its concern that a claim construction dispute still remained over the “wrap around” term in the ’822 patent:

In September, the court held a three-bench trial, after which the parties submitted proposed findings of fact and post-trial briefs.

After re-examining this evidence, the court reversed its previous construction of a disputed claim term in the ’822 patent to “require that the second region is configured to curve onto a terminal endpoint and back around such that the hook shaped projections are substantially parallel to the longitudinal axis of the bone at the terminal end”.

Judge Noreika concluded: “The parties having agreed that this requires a finding of non-infringement and that Arthrex’s invalidity counterclaim may be dismissed as moot, there are no further issues that require the court’s resolution.”