Duty-Centered “No New Theory” Rule in Medical Malpractice Summary Judgment: Pre‑Surgical Positioning as a Permissible Elaboration of a Pleaded Positioning Claim

1. Introduction

Lopez v Millard Fillmore Suburban Hosp. is a Fourth Department medical malpractice decision addressing two recurring procedural flashpoints: (1) what a defendant must show on summary judgment in malpractice cases involving competing experts, and (2) when an opposing expert affidavit “changes” the plaintiff’s theory of liability versus permissibly elaborating it.

The plaintiff, Daniel Lopez, alleged that he suffered left-leg compartment syndrome after a gastrointestinal surgery performed by Timothy M. Adams, M.D., associated with Delaware Surgical Associates (collectively, “defendants”). The pleaded theory centered on improper positioning/monitoring during surgery leading to compromised circulation. Defendants moved for summary judgment, arguing no departure from accepted practice and, separately, that plaintiff’s opposition asserted a “new theory” (pre-surgical positioning). Supreme Court denied the motion; the Fourth Department affirmed.

Key issues: (i) whether defendants met their prima facie burden; (ii) whether plaintiff’s expert raised a triable issue; and (iii) whether focusing on initial positioning (pre-incision) is an impermissible “new theory of liability” given the pleadings and bills of particulars.

2. Summary of the Opinion

The court held that defendants established a prima facie showing of no deviation regarding the performance of the GI surgery through a detailed expert affidavit. The burden therefore shifted, and plaintiff met it with an opposing expert affidavit identifying departures in the initial positioning and intraoperative monitoring of leg circulation (including palpation) that—given the surgery length—could cause compartment syndrome. This created a triable issue as a “classic battle of the experts” for the jury.

The court also rejected the “new theory” argument: the case “at all times” remained about undue pressure/circulatory compromise from improper positioning in connection with the surgery. Whether the offending positioning occurred immediately before surgery began or during surgery did not alter the underlying theory and did not unfairly surprise defendants.

Justice Curran concurred in the result, adding two points: (1) a “new theory” analysis should be duty-centered and grounded in the complaint; and (2) defendants’ hyper-literal parsing of bills of particulars misapprehended CPLR 3043—bills of particulars require only general statements of negligent acts/omissions and are not a vehicle for evidentiary minutiae or expert-level standard-of-care explication.

3. Analysis

3.1 Precedents Cited

A. Summary judgment framework in medical malpractice

• Bubar v Brodman and Campbell v Bell-Thomson: The court invoked these Fourth Department authorities for the canonical burden rule—defendants must initially establish either no departure from accepted practice or no causation; only then does the burden shift “only as to the elements on which the defendant met the prima facie burden.” These cases supplied the controlling template for evaluating the parties’ expert proof.
• Carroll v Niagara Falls Mem. Med. Ctr.: Used to confirm what counts as sufficient prima facie expert proof—an affidavit that is “detailed, specific and factual in nature” and addresses the plaintiff’s “specific claims of negligence.” The court relied on Carroll to conclude defendants’ expert submission was adequate to shift the burden.
• Nowelle B. v Hamilton Med., Inc.: Applied for the proposition that directly conflicting competent expert affidavits create a triable issue—“a classic battle of the experts” reserved for the jury. This precedent was decisive to the affirmance once plaintiff’s expert specifically contradicted defendants’ expert on positioning/monitoring.

B. “New theory of liability” versus elaboration of an existing theory

• Hart v City of Buffalo and Jeannette S. v Williot: The majority cited these for the rule that an “underlying theory of liability” remains unchanged where the essential duty alleged to have been breached remains the same, even if the plaintiff refines how the breach occurred. Justice Curran expanded this duty-centered lens, explaining that the “theory” is rooted in the duty, not in a defendant’s preferred level of factual granularity.
• Valenti v Camins and Alvord & Swift v Muller Constr. Co.: Cited to support the “no unfair surprise” inquiry—if the refined allegations are “discernible from the pleadings,” they are not barred as new theories. The court leveraged these to hold that pre-surgical positioning fell within the pleaded positioning/circulation theme.
• Braxton v Erie County Med. Ctr. Corp.: Justice Curran quoted it for the methodological starting point—focus “initially” on the complaint’s allegations when deciding whether a new theory has been raised. This anchored the concurrence’s argument that the complaint’s duty-and-breach allegations governed, not the defendants’ word-by-word parsing of bills of particulars.
• Darrisaw v Strong Mem. Hosp. (and affirmance): Cited generally to reinforce the complaint-centered approach to whether a theory is new. Its presence signals that the Fourth Department views this as a stable, appellate-approved analytical pathway.

C. Contrast cases where a new theory truly is “new”

• Hewitt v Palmer Veterinary Clinic, PC, Guyett v Kaleida Health, Walker v Caruana, DeMartino v Kronhaus: Justice Curran invoked these as contrasts—summary judgment may be appropriate where opposition relies on breach of a different duty or different actors. These citations sharpen the boundary: elaboration on the same duty/actor is not a new theory; switching the duty-holder or duty type is.

D. Bills of particulars are not disclosure devices (CPLR 3043 context)

• Northway Eng'g v Felix Indus. and Stern v Golub Corp.: Cited for the settled point that a bill of particulars is not a disclosure device—i.e., it is meant to amplify pleadings, not function as discovery.
• Nuss v Pettibone Mercury Corp., Khoury v Chouchani: Used to reiterate that bills of particulars cannot be used to extract evidentiary material; the plaintiff is not required to “hire an expert” merely to answer a bill demand. This undercut defendants’ insistence on precise time-stamped, mechanism-by-mechanism particulars.
• Sonnenberg Gardens v Eldredge, Fox & Porretti, LLP and Heyward v Ellenville Community Hosp.: Cited for rejecting demands that require listing “each and every way” a duty was breached—because doing so typically requires expert evidentiary content.
• Chipley v Stephenson, Stidham v Clerk, Garrett v Community Gen. Hosp. of Greater Syracuse: Cited to confirm CPLR 3043’s application in medical malpractice and to support appropriate limits on particularization demands in that setting.
• McKenzie v St. Elizabeth Hosp.: Cited for the specific malpractice point that demands seeking “usual and accepted standards” and what advice/diagnosis/treatment should have been given call for expert testimony and are “purely evidentiary.”
• Grcic v Peninsula Hosp. Ctr. and Randall v Pech: Cited for the policy rationale: malpractice plaintiffs often lack access to knowledge of proper procedures; they should not be held to a greater pleading/particularization burden than other personal injury plaintiffs.

3.2 Legal Reasoning

A. Prima facie showing and burden shifting

The court applied the orthodox malpractice summary judgment structure:

• Step 1 (Defendants’ burden): show no departure or no causation through competent proof (typically expert testimony).
• Step 2 (Shift): only after Step 1, plaintiff must raise a triable issue on the specific element(s) defendants negated.

Here, the court credited defendants’ expert affidavit as sufficiently “detailed, specific and factual,” and as responsive to plaintiff’s asserted negligence theories concerning the surgical performance. That showing shifted the burden.

B. Triable issue via competing experts (“battle of the experts”)

Plaintiff’s expert directly countered defendants’ narrative by identifying departures in:

• the initial positioning of the left leg,
• failure to monitor left-leg circulation intraoperatively (including palpation), and
• the inference that, given the length of the surgery, the positioning/monitoring failures caused compartment syndrome.

Because this affidavit “squarely oppose[d]” defendants’ expert, the case fit the Nowelle B. pattern: credibility and weight of expert views are for the jury, not summary judgment.

C. No “new theory of liability” where duty and actor remain constant

The defendants’ central procedural argument was that plaintiff pivoted from “during surgery” to “before surgery” positioning. The majority (and especially the concurrence) treated this as a false dichotomy: the pleaded and particularized theme was always improper positioning/pressure and inadequate circulation precautions in connection with the surgery.

Justice Curran refined the doctrinal framing: a “theory of liability” is identified by the duty allegedly breached (and by whom), not by the most granular description of the breach. Thus, alleging improper positioning “at the time of the surgery” was not new because it implicated the same duty of the same surgeon. The concurrence distinguished the “new theory” cases where the duty changed or a different actor’s duty was introduced.

D. Bills of particulars: general notice, not expert-driven micro-particularization

The concurrence’s second point addresses litigation practice more than outcome, but it is doctrinally important. Defendants’ insistence that the bill of particulars should have enumerated each specific positioning failure and its precise timing was rejected as inconsistent with CPLR 3043’s requirement of only a “general statement of the acts or omissions constituting the negligence claimed.”

The cited authorities establish that bills of particulars:

• are not discovery tools (Northway Eng'g; Stern);
• cannot demand evidentiary detail or expert standards-of-care content (Nuss; Khoury; McKenzie);
• should not impose a heavier burden on malpractice plaintiffs who lack access to technical knowledge (Grcic; Randall).

On these principles, plaintiff’s positioning-focused bills were sufficient notice, and any refinement about “when” the positioning failure occurred (pre- vs intra-operative) was treated as a permissible elaboration—especially where deposition testimony and defendants’ own expert discussion indicated defendants were on notice that positioning was at issue.

3.3 Impact

• Clarifies “new theory” policing in malpractice: The decision reinforces a duty-based approach: if the same defendant owed the same medical duty and the claim remains rooted in that duty’s breach, courts should be reluctant to label opposition proof as a “new theory” merely because it adds timing/mechanism detail.
• Strengthens plaintiffs’ ability to oppose summary judgment with refined expert narratives: Plaintiffs may more safely articulate, through experts, specific sub-mechanisms (e.g., initial positioning) within a broadly pleaded malpractice theory (e.g., improper positioning/monitoring causing circulatory injury), so long as the core duty/breach is unchanged.
• Constrains overreaching bill-of-particulars arguments: The concurrence is a pointed reminder to litigants and trial courts that CPLR 3043 is about notice, not extracting expert-level proof. This may reduce successful “gotcha” summary judgment strategies premised on hyper-technical comparisons among bills served on different defendants.
• Jury-triable expert disputes: By framing the conflict as a “classic battle of the experts,” the decision underscores that malpractice cases with competent, competing experts will often be resolved at trial rather than on motion practice.

4. Complex Concepts Simplified

• Summary judgment: A pretrial ruling that ends a claim without trial if no “triable issue of fact” exists. In malpractice, it commonly turns on whether expert proof creates factual disputes.
• Prima facie burden (defendant): The moving defendant must first show—through admissible evidence, typically an expert affidavit—no departure from accepted practice or no causation.
• Triable issue of fact: A genuine factual dispute requiring a jury (or factfinder) to decide. Competing credible experts on the standard of care usually create one.
• “Battle of the experts”: When both sides present qualified experts who disagree on the standard of care and causation, courts typically leave resolution to the jury.
• New theory of liability vs. new evidentiary detail: A “new theory” generally means a different duty, a different wrong, or a different duty-holder. Adding detail about how/when the same duty was breached (e.g., pre-surgical vs intraoperative positioning) is often treated as elaboration, not a new theory.
• Bill of particulars (CPLR 3043): A notice document that amplifies pleadings by giving a general statement of negligent acts/omissions; it is not a substitute for discovery and does not require expert evidentiary disclosures.
• PJI 2:150 (referenced in the concurrence): A standard jury instruction describing the medical professional’s duty to exercise the level of knowledge and skill expected of an average specialist in the relevant community.
• Compartment syndrome (context): A limb-threatening condition often associated with increased pressure within muscle compartments; in this case, it is alleged to have resulted from prolonged improper positioning and compromised circulation during surgery.

5. Conclusion

Lopez v Millard Fillmore Suburban Hosp. affirms denial of summary judgment where the parties’ experts squarely dispute whether surgical positioning and circulation monitoring met accepted standards and caused compartment syndrome—an archetypal jury issue.

More significantly as a procedural precedent, the decision (and concurrence) frames “new theory of liability” through a duty-based, complaint-centered lens: a plaintiff does not assert a new theory merely by specifying that the same positioning breach occurred at the outset of surgery rather than during it. The concurrence also forcefully reiterates that bills of particulars under CPLR 3043 provide general notice and cannot be weaponized to demand expert-level evidentiary detail.