## Facts

- Patrick O’Shea had a prior gunshot injury that left his left leg shorter and caused an abnormal gait and chronic knee pain.
- In 2007, his surgeon implanted a Zimmer NexGen Complete Knee Solution LPS-Flex Prolong System knee device.
- O’Shea continued to experience pain after surgery; later imaging showed loosening of femoral and tibial components.
- The implant allegedly failed prematurely and was revised in 2015.
- O’Shea alleged the device contained a manufacturing defect that caused loosening and failure.
- O’Shea relied primarily on circumstantial evidence (early failure, evidence of proper implantation, and lack of other obvious causes) rather than proof identifying a specific manufacturing error.
- O’Shea sued Zimmer-related entities under Georgia law for strict liability (manufacturing defect), negligence, failure to warn, and breach of implied warranty.
- Defendants moved for summary judgment on all claims in a federal diversity action.

## Issues

1. Whether circumstantial evidence was sufficient under Georgia law to create a triable issue that the knee implant had a manufacturing defect that proximately caused O’Shea’s injuries.
2. Whether O’Shea produced evidence of warning inadequacy and proximate causation under Georgia’s learned-intermediary doctrine.
3. Whether O’Shea’s implied-warranty claims were supported by required elements (including privity and proof of breach) on the summary-judgment record.

## Decision

- The court granted in part and denied in part defendants’ motion for summary judgment.
- The court denied summary judgment on O’Shea’s manufacturing-defect claims (strict liability and negligence), holding a reasonable jury could infer defect and causation from the circumstantial record.
- The court granted summary judgment on the failure-to-warn claim, concluding O’Shea failed to show that different warnings would have changed the implanting surgeon’s decision or prevented the injury.
- The court granted summary judgment on certain implied-warranty theories due to failure to satisfy required warranty elements on the record.

## Legal Principles

- Under Georgia law, a manufacturing defect may be proven by circumstantial evidence; direct proof of a specific production flaw is not always required.
- A plaintiff can survive summary judgment on manufacturing defect by showing facts supporting an inference that the product deviated from its intended condition and that the deviation caused the injury, including evidence of proper use/implantation and the absence of likely alternative causes.
- Georgia products-liability negligence requires proof of duty, breach, causation, and damages; circumstantial proof supporting defect and causation can also support breach and causation for negligent manufacture.
- Under Georgia’s learned-intermediary doctrine for prescription medical products, the duty to warn runs to the physician, and the plaintiff must show proximate causation by evidence that an adequate warning would have altered the physician’s decision-making in a way that would have avoided the harm.
- Warranty claims require satisfaction of distinct statutory and common-law elements (including, in some circumstances, privity), and may fail at summary judgment even when tort defect claims proceed.

## Conclusion

The court held that O’Shea’s manufacturing-defect theories could proceed to trial based on circumstantial evidence of premature failure and proper implantation, but it dismissed the failure-to-warn claim for lack of causation under the learned-intermediary doctrine and dismissed certain implied-warranty claims for failure to establish required warranty elements.


O’Shea v. Zimmer Biomet Holdings, Inc., 342 F. Supp. 3d 1354 (N.D. Ga. 2018)