## Facts

- David Jorgenson, a South Dakota resident, shattered his right leg and ankle while on vacation in Wisconsin in August 1997.
- A Wisconsin physician treated the fracture by placing pins and stabilizing the leg with an external fixator.
- After returning to South Dakota, Jorgenson began follow-up care with Dr. Michael Vener, an orthopedic surgeon.
- Jorgenson had drainage around the pin sites; Vener prescribed antibiotics, but the symptoms did not resolve.
- Jorgenson returned for additional visits with worsening signs of infection.
- As the condition progressed, Vener recommended that Jorgenson see another doctor in Fargo to address the infection.
- Jorgenson instead went to the Mayo Clinic, where physicians diagnosed a bone infection and advised two options: a prolonged course of reconstructive treatment (described as taking about two years with an estimated 60% chance of success) or immediate below-the-knee amputation.
- Jorgenson chose amputation, which was performed in December 1997.
- Jorgenson and his wife, Sheryl, sued Vener for medical malpractice. They supported the claim with an affidavit from Dr. Mark E. Rupp (infectious-disease physician), stating that Vener’s failure to timely diagnose and treat the infection caused Jorgenson a lost chance to avoid amputation.
- Vener moved for summary judgment, arguing South Dakota did not recognize a loss-of-chance theory and that Jorgenson could not show proximate cause under traditional standards.
- The circuit court granted summary judgment for Vener based on its conclusion that loss of chance was not compatible with South Dakota law, and the Jorgensons appealed.

## Issues

1. Whether South Dakota recognizes “loss of chance” as a compensable injury in a medical-malpractice action.
2. If loss of chance is recognized, what causation showing is required: whether the plaintiff must prove, by a preponderance of the evidence, that the defendant’s negligence more likely than not reduced the patient’s chance of a better outcome.
3. If loss of chance is recognized, how damages should be measured when the injury claimed is the probability of a better outcome that was reduced or destroyed.

## Decision

- The South Dakota Supreme Court reversed the summary judgment and remanded.
- The court held that loss of chance is an actionable injury at common law in South Dakota medical-malpractice cases.
- The court explained that the doctrine does not remove the requirement of proximate causation; the plaintiff must still prove, by a preponderance of the evidence, that the defendant’s negligence caused a reduction in the chance of a better outcome.
- The court stated that the compensable injury is the lost chance itself, not the entire underlying adverse result.
- The court approved measuring damages by valuing the lost chance as a percentage of the value of the total harm avoided (proportional recovery), whether the pre-negligence chance was below or above 50%.
- Because the circuit court rejected the claim as a matter of law, summary judgment was improper and the case had to proceed under the loss-of-chance approach.

## Legal Principles

- A reduced probability of a better medical result can be a compensable injury in medical malpractice; the “lost chance” is treated as the injury.
- Proximate cause remains a required element; the plaintiff must prove by a preponderance of the evidence that the defendant’s negligence caused the reduction or destruction of the chance of a better outcome.
- The causation inquiry focuses on whether negligent care more likely than not caused the loss of the chance, not whether negligent care more likely than not caused the ultimate amputation or other final outcome.
- Damages may be awarded in proportion to the value of the chance lost (e.g., a 40% lost chance may be valued at 40% of the damages associated with the avoided harm), and recovery is not limited to cases in which the original chance exceeded 50%.
- Statistical and probability evidence may be used to value the lost chance, and proportional valuation avoids an all-or-nothing result when negligent treatment reduces a meaningful chance of a better outcome.

## Conclusion

The South Dakota Supreme Court held that a patient may sue for medical malpractice based on loss of chance, requiring proof that the physician’s negligence more likely than not reduced the patient’s chance of a better outcome and permitting damages measured as the proportionate value of that lost chance; it reversed summary judgment for the physician and remanded for further proceedings.


Jorgenson v. Vener, 616 N.W.2d 366, 2000 S.D. 87 (2000)