Surgical cultures vary between countries for many different reasons. Countries have different surgical histories and local traditions; the ability of surgeons to perform and their interest in research activities may differ. In addition, the quality of orthopaedic teaching for residents, the organization of academic centers, the organization of public healthcare systems, and healthcare budgets all have an impact on surgical cultures.

Although evidence-based medicine (EBM) aims to define best practices, its interpretation is subjective, and so far, EBM has not standardized surgical practices within a country, let alone around the world. For example, hip arthroplasty is viewed and treated differently within France—guest nation at the 2014 AAOS Annual Meeting—than it is in the United States but both approaches have been helpful in improving orthopaedic knowledge.

Differences relating to primary THA
Although the posterior approach is used in both France and the United States, the direct anterior approach is becoming more popular due to its potential for reducing the dislocation rate and accelerating recovery. Among the differences between the French and American surgical cultures with regard to primary total hip arthroplasty (THA) are the following:

• choice of bearing surface for young, active patients
• management of the risk of dislocation
• choice of implant fixation

Bearing surfaces—In the United States, metal-on-highly cross-linked polyethylene is the bearing of choice for young, active patients. Ceramic-on-ceramic (CoC) bearings have been criticized for having an excessive risk of fracture as well as for squeaking, and metal-on-metal bearings have been basically abandoned due to concerns about adverse local tissue reactions and the potential systemic effects of metal ion release.

In France, however, CoC bearings have been used for patients younger than age 65 for the past 40 years. When French surgeons compare their long-term experience with ceramic bearings to the much shorter use of highly cross-linked polyethylene in this high-demand population, they are reluctant to adopt polyethylene as the bearing standard. In France, a highly cross-linked polyethylene liner is more frequently used in patients older than age 70.

Management of dislocation risk—In the United States, large-diameter heads are used to prevent dislocation, occasionally augmented with the use of a constrained liner. In contrast, French surgeons use the mobile-bearing dual mobility cup in patients at risk of dislocation, including those with neurologic diseases, revision patients, elderly patients older than 70 years, patients with spine-hip syndrome (a stiff and/or deformed spine and the risk of femoroacetabular impingement); and noncompliant patients. The mobile-bearing dual mobility cup has good survivorship and a low dislocation rate at up to 17 years follow-up, although most studies have been poorly designed.

Implant fixation—In the United States, uncemented THA is popular in all patient age groups and has excellent long-term results. In France, although uncemented cup fixation is well accepted for young, active patients, cemented cup fixation continues to be the most commonly used fixation method for elderly patients.

The most appropriate form of stem fixation is still being debated in France. Excellent long-term results have been obtained using a cemented stem with a very thin cement mantle, thick enough only to fill the irregular space between the stem and the bone. This so-called “French paradox” cementation technique relegates the cement mantle to a “void filler” that has only a small role in implant fixation. The primary stabilization is provided by a bone press-fit, which reduces cement debris and stem fretting-corrosion.

With regard to stem design in uncemented THA, tapered titanium and cylindrical chrome-cobalt alloys are popular in the United States and achieve excellent fixation results. In contrast, French surgeons tend to use mostly anatomic or double-taper, hydroxyapatite fully coated stems.

Conclusion
American and French surgical cultures regarding THA are both very rich. Unfortunately, the absence of high-quality studies proving the reliability of French concepts regarding THA has meant that some of these concepts may be undervalued. The French Hip Society has approved concepts that seem to work well over time, but it relies on expert opinion and the conclusions of retrospective studies. These concepts must be validated before they can be released for adoption around the world, because they seem to be perfectly compatible and complementary with American concepts. Such cross-fertilization may be of value and improve outcomes in both countries.

Charles Riviere, MD, is a professor in the department of orthopaedic surgery, Hôpital Pellegrin, Université Victor Segalen, in Bordeaux, France.

Learn more about cross-cultural differences
As part of the Guest Nation program at the 2014 AAOS Annual Meeting, three instructional courses and 10 special posters from France will be featured. Members of the Société Française de Chirurgie Orthopédique et Traumatologique (SOFCOT) will moderate and serve as faculty for the following three instructional course lectures (ICLs):

• ICL 122: International Perspective on Improving the 10-year Outcome of Total Knee Arthroplasty: Get It Right the First Time—March 11, 10:30 a.m.–12:30 p.m.
• ICL 147: International Perspective on Preventing and Dealing with Complications in Reverse Shoulder Arthroplasty—March 11, 1:30 p.m.–3:30 p.m.
• ICL 151: International Perspective on the Masquelet Technique for the Treatment of Segmental Defects in Bone—March 11, 1:30 p.m.–3:30 p.m.
• Register online today at www.aaos.org/annual