In their 2013 New England Journal of Medicine article, Birkmeyer et al¹ studied bariatric surgeons to see if there was a relationship between their surgical skills and clinical outcomes. Twenty bariatric surgeons were enrolled in the prospective study. Video recordings were made of each surgeon performing a laparoscopic gastric bypass operation. These videos were then examined by independent, blinded peers who rated surgeon technical skills on a standard rating scale. The authors then looked for a relationship between surgeon skill scores and risk-adjusted complication rates using a prospective, clinical outcomes registry that had more than 10,000 patients. Not surprisingly, surgeons who had scored in the bottom quartile of surgical skills had a longer duration of surgery, more complications, higher rates of reoperation and patient readmissions, and increased patient mortality compared with the top quartile of surgeons in the study. The study exposed an uncomfortable truth (ie, surgeon skills and attendant clinical outcomes are probably linearly correlated and that not all surgeons are the best with their hands and psychomotor skills).

Although blinded peer rating of surgical skills may quantify surgeon proficiency, a different issue arises when a new skill, such as DAA THA, is introduced to surgeons already in practice. Proficiency refers to competence, or skill, as measured by peer review, outcomes, lack of complications, lower mortality rates, and other metrics. These metrics are a function of the quality of the initial training and cumulative experience with executing a specific surgical procedure. A generally accepted standard for the adoption of a new surgical method has been the ease of its reproducibility, which refers to the ability of other surgeons to learn and safely perform the operation in their practices after appropriate training and mentorship. The inherent assumption in this standard of reproducibility is that all willing surgeons will be able to master the new technique, with some taking longer than others, provided that some universally accepted threshold of training and education has been met. As hip replacement surgery has become more specialized, less invasive methods promising quicker recovery have been promoted extensively. Some, if not all, of these new techniques may be technically challenging, especially for surgeons who are accustomed to direct visualization of anatomic structures in an open, expanded surgical field. One element of surgeon self-examination relates to a candid appraisal of one’s skill set to see if the benefits of adopting a new technique outweigh the risk created in learning it. This appraisal can be facilitated by understanding the legal liability arising from physician learning and adoption of new surgical techniques.

Although complications related specifically to DAA THA have been described in the literature, legal data concerning negligence claims and underlying injuries related to the operation are difficult to come by. Many legal claims go no further than chart review, whereas others are settled or dismissed without reliable records. In order to gather data on the incidence and type of complications related to DAA THA that led to legal inquiry or resulted in a verdict in a medical malpractice action, data from two sources were combined.

One source was VerdictSearch, a national, commercial database that collects information from the defense and plaintiff counsel after a legal case has had a verdict issued. The second source was a medical malpractice law referral center with a large intake volume of complaints from clients alleging medical injuries. Both sources were searched for injuries related to total hip replacement in which the DAA had been used; the search encompassed a 10-year period from June 2010 to May 2020. The purpose of this survey was to identify the nature of injuries sustained during DAA THA that led to patients seeking legal redress.

A total of 46 cases were identified from these sources. Of these, 14 (30%) had a permanent nerve injury as the basis for the complaint (seven femoral nerve, two
sciatic nerve, three lateral femoral cutaneous nerve, and two peroneal palsies). Ten (22%) of the cases involved an arterial injury (eight femoral artery and two iliac vessels); of the two with an iliac vessel injury, one patient ultimately died of complications related to hemorrhagic shock and the other had a limb disarticulation from complications related to thigh compartment syndrome. Eight cases (17%) were related to complications arising from component malpositioning, and another six cases (13%) involved fractures of the acetabulum or femur. The remaining eight cases invoked a variety of other complications (leg length discrepancy in four, infection in two, and persistent pain and perineal skin necrosis in one each).

In these 46 cases, a review of the records showed that the mean operative time was 3.7 hours (range, 2.5-9.0 hours) and the mean blood loss during surgery was 2200 mL (range, 1700-3100 mL). The blood loss and duration of surgery suggest a lack of competency in performing the DAA, and the nature of the other neurovascular complications suggests an unfamiliarity with the surgical anatomy of the anterior hip, specifically in understanding the spatial relationship of the femoral neurovascular bundle and iliac vessels to the operative field. No data were available to allow reliable correlation of these complications to the level of surgeon experience.

Aside from professional negligence risk that gives rise to legal claims against the surgeon, enterprise risk should also be considered when adopting a new technology into one’s practice. Enterprise risk refers to systemic risk in an organization from the cumulative actions of stakeholders. Enterprise risk management entails a business strategy to proactively identify, manage, and mitigate the risks that can interfere with an organization’s operations and objectives. The present era in medicine is driven by transparency, information technology, quality measures, and consumer empowerment. Health care payers are increasingly focused on outcomes and costs. Should a hospital be required to quantify and react to the different outcomes of its surgeons in light of the findings of Birkmeyer et al¹ that show variations in clinical outcomes depending on surgeon skill? If a surgeon has complications related to DAA THA and such complications occur at a higher incidence than other standard methods of THA, should the hospital be held liable for the complications?

These are hard questions that are nonetheless inescapable in the new and rapidly changing world of health care with its renewed focus on patient safety. To answer them, one must first examine the legal precedents that created hospital liability in the first place for the acts of its medical staff. This exercise is especially relevant at a time when more physicians are accepting a practice model that makes them a hospital or corporate employee.²

The legal doctrine known as respondeat superior (Latin for “let the master answer”) creates liability for an employer for the negligent acts of its employees. This doctrine is commonly invoked to hold an employer responsible for the actions of their employees or agents if such actions occur within the scope of employment or agency. This common law doctrine was established in 17th century England and was adopted in the United States as a fixture of a branch of law called agency law. Agency law helps define the legal relationship between an employer and its employees. It provides a better chance for an injured party to recover damages because under respondeat superior the employer is liable for the injuries caused by an employee who is working within the scope of their employment relationship.

Thus, if a surgeon-employee injures a patient during the DAA, the application of the respondeat superior doctrine is relatively straightforward. For injuries arising out of physician conduct during the scope of employment, courts have little trouble finding that the hospital (ie, the employer) should be held liable as well, but respondeat superior does not address the conduct of those surgeons who are independent (ie, not employees of a hospital). Having privileges at a hospital does not create or imply an employer-employee relationship. Still, independent surgeons must formally apply for privileges, and the hospital must clearly delineate the scope of their hospital practice. Credentialing is the process of applying for and being accepted to a hospital medical staff. Privileges, or privileged delineations, are the physician or surgeon’s permissible scope of practice within a hospital. How does the legal system create hospital liability for the actions of medical staff members who are not hospital employees?

In 1965, the legal ruling in the Illinois case of Darling v. Charleston Community Memorial Hospital created hospital liability for physician negligence.³ From this case onward, US courts have recognized and enforced a doctrine called hospital corporate liability, which creates a direct duty of a hospital to ensure the competency of its medical staff, as well as appropriate limitations on a medical staff member’s privileges. Essentially, hospital corporate liability is an extension of respondeat superior in that, even though private physicians may not be employees of a hospital, their actions will impute to the hospital because the hospital credentialed them and granted them privileges, thereby creating a legal relationship, even absent direct employment. Up until this ruling, hospitals had been able to escape liability for injuries caused to patients by members of the medical staff, arguing that no employer-employee relationship existed.

In this case, an 18-year-old man suffered a lower extremity fracture during a football game. He was seen
in the emergency room, and the on-call doctor placed the leg in a cast. Compartment syndrome developed and went unrecognized until, at a different hospital, a below-knee amputation was performed. The plaintiffs presented a new legal theory of liability, contending that the hospital was responsible for ensuring that its patients were treated by competent medical staff members. Agreeing with this premise, the court said that the trial evidence revealed that “… the hospital failed to review Dr. Alexander’s work… its failure to do so was negligence. On the evidence before it, the jury could reasonably have found that [the hospital] was [negligent].”³

The defense argument that the hospital does not treat the patient and does not act through its doctors and nurses but undertakes instead simply to procure them to act upon their own responsibility was soundly rejected by the court. The decision in this case has withstood the test of time and is the basis for naming hospitals as independent defendants in medical malpractice cases today.

In the years that followed the ruling in Darling v. Charleston Community Memorial Hospital, other legal cases have upheld the doctrine of hospital corporate liability. In Elam v. College Park Hospital,⁴ a podiatrist faced a lawsuit alleging negligent surgery. It was discovered that the hospital peer review committee had previously voiced concerns about the podiatrist’s incompetence and lack of qualifications but had never alerted the hospital administration of these concerns. Applying the doctrine of hospital corporate liability, the court found the hospital liable, holding that “the hospital owed a general duty to ensure the competency of its medical staff and to evaluate the quality of medical treatment rendered to its patients.”⁴