Broke the chain of causation

Medical malpractice cases often hinge on proving that a healthcare provider’s negligence directly caused a patient’s injuries. However, the legal concept of “proximate cause” can be complex, particularly when a patient’s own actions intervene between the alleged malpractice and the resulting harm. The Second Department’s decision in Wilkins v Khoury illustrates how a patient’s failure to follow subsequent medical advice can sever the causal connection, even when the original provider may have committed malpractice.

This principle of intervening causation appears frequently in personal injury litigation and no-fault insurance disputes, where determining the true cause of injuries affects both liability and coverage decisions. Understanding when an intervening act “breaks the causal nexus” is crucial for practitioners handling medical malpractice and insurance coverage cases.

Jason Tenenbaum’s Analysis:

Wilkins v Khoury, 2010 NY Slip Op 03435 (2d Dept. 2010)

“While the plaintiff, in opposition, raised a triable issue of fact as to whether the defendants departed from good and accepted podiatric practice by failing to diagnose her potentially gangrenous condition and failing to instruct her to go to a hospital immediately for intravenous antibiotic treatment, she failed to raise a triable issue of fact as to whether the defendants’ conduct was a proximate cause of her injuries (see Brocco v Westchester Radiological Assoc., 175 AD2d 903, 904-905). The plaintiff’s voluntary act of not going to the hospital for intravenous antibiotic treatment when she was instructed to do so by an orthopedic surgeon, who saw the plaintiff after she was treated by the defendants, was independent of and far removed from the defendants’ conduct and, thus, was a superseding act which broke the causal nexus (see Pierre v Lieber, 37 AD3d 572; Brocco v Westchester Radiological Assoc., 175 AD2d at 904-905).”

The question of whether an intervening act breaks the causal nexus between the accident and injury plays out frequently enough in no-fault practice that it seems instructive to follow this line of cases.

Key Takeaway

Even when medical malpractice is established, a patient’s failure to follow subsequent medical instructions can constitute a superseding act that breaks the chain of causation. Courts will examine whether the intervening act was voluntary, independent, and sufficiently removed from the original alleged negligence to sever liability.

Related Articles

• Understanding how medical expert testimony impacts causation in personal injury cases
• Key causation lessons from summary judgment decisions
• How insufficient medical affirmations can break causal connections
• When triable issues exist regarding injury causation in motor vehicle accidents
• Personal Injury

Legal Update (February 2026): Since this post’s publication in 2010, New York courts have continued to refine the application of intervening causation principles in medical malpractice cases, and practitioners should verify that the causation standards and burden of proof requirements discussed remain current under recent Second Department and Court of Appeals precedent. Additionally, any intersection with no-fault insurance coverage determinations may reflect updated regulatory interpretations of causation requirements.