Climate change is a global crisis. Historically, earth's climate has been characterized by cycles of warming and cooling [1]. Levels of atmospheric gases, including carbon dioxide (CO2), wax and wane within these cycles. Over the past 800,000 years, the level of CO2 never rose above 300 parts per million (ppm) until 1950; since that time, there has been an exponential rise to the current level of 415 ppm [[1], [2], [3]] (Fig. 1). Earth's temperature has followed the same pattern, in direct correlation with CO2 levels, which as a greenhouse gas absorbs, traps, and redirects energy from the sun back to earth. Environmental consequences of climate change are evident in the fires of America's West and the collapsing polar ice cap. Medical consequences follow the environmental, including pulmonary disease from poor air quality, changes in soil and water that threaten the food supply, and habitat disruption that increases vector-borne diseases [4].

One climate change mitigation strategy is calculating and reducing carbon footprint. The carbon footprint is defined as the amount of CO2 emitted by an individual, activity, or organization. This can be translated into the biocapacity (such as number of trees) needed to neutralize the CO2. For context, driving a gasoline automobile 100 miles is equivalent to emission of nearly 100 lb CO2 [5], while a tree can absorb approximately 48 lb CO2per year [6]. The USA has the second largest total carbon footprint; it also has the second largest healthcare carbon footprint [7,8] (Fig. 3). Worldwide, healthcare is responsible for 4.4 % of greenhouse gas emissions [9]. In the USA, healthcare's carbon footprint approximates 10 % of the country's total [10]. This footprint has increased by 30 % between 2006 and 2016 [11]. As a result, members of the healthcare sector, including Orthopædic Surgery, have a responsibility and an opportunity to positively impact climate change by reducing healthcare's significant and rapidly rising carbon footprint.

A now established carbon mitigation strategy in medicine is the video visit. In 2013, more than 95 % of orthopædic surgeons were unfamiliar with telemedicine; in 2017, only 20 % of orthopædic surgeons believed telemedicine would be helpful for routine postoperative follow-ups [12]. Before 2020, telemedicine represented approximately 0.7 % of all patient-physician interaction in urban areas, and approximately 1.1 % of all patient-physician interaction in rural areas. By June of 2020, these percentages increased to approximately 22.0 % and 14.7 % of all patient-physician interaction in urban and rural areas, respectively [13]. Furthermore, after the pandemic, insurers indicated that only 4 % of their patients do not use telehealth services [14].

Another area that has gained attention recently is the environmental impact of medical interviews [[15], [16], [17]]. Medical interviews contribute significantly to the carbon footprint of the healthcare sector, shining a spotlight on the necessity and scope of their in-person format. For example, one study of residency interviews showed that each applicant produced mean CO2 emissions greater than the global average annual emissions limit outlined by the 2016 Paris Climate Agreement [16]. Our study expands upon previous findings by bringing carbon footprint calculation to Orthopædic Surgery in the U.S., an area not previously studied, looking specifically at the impact of in-person versus virtual interviews for Orthopædic Surgery residency. Our results inform the Orthopædic community as it joins the broader effort to reduce the carbon footprint of healthcare.