The main finding of this study is the increase in the rates of RCS in Chile during 2008–2018, in accordance with the literature published internationally, being the first national report on RCS rates.
During the 10-year study period, the calculated rate of RCS was 32.36 procedures for every 100,000 Chilean inhabitants over 25 years old; below than the rate reported for European countries (Italy, 62.1 per 105 [2001–2014] [9], Finland, 44 to 131 per 105 [1998–2011] [14]); the United States (41 to 98 per 105 [1996–2006] [11]), and Asia (Korea, 13.15 to 116.04 per 105 [2007–2015] [13]). Compared with RCS rates for Brazil (0.83 to 2.81 per 105 [2003–2015] [16]), we found a higher rate in a similar period. The causes of these differences were not evaluated in this study, but they are likely related to socioeconomic factors and the gross domestic product that are believed to influence access to surgery and its costs [13].
RCS rates present statistically significant differences according to the variables analyzed. In Chile, there is a higher rate of surgery observed in women (male:female ratio 0.84:1) throughout the period, in contrast with the higher rates in men in other countries. In Finland, the male to female ratio is 1.7:1 [14], while in Korea and Italy is 1.02:1 [9, 13].
However, there are similarities in the age range, with the highest rate of RCS between 45 and 65 years [9]. In Korea, the mean age of patients who received RCS was 55.4 years (SD ± 10.8) [13]. The mean patient age at the time of operation in Finland increased from 55 (SD 9) years in 1998 to 56 (SD 10) years in 2011 [14]. In the US, it is precisely this age group (45–65 years) that presents the greatest increase in RCS, mainly with arthroscopic technique (2 to 10 per 105 to 21 to 146 per 105) [11].
The main difference with respect to international reports is in relation to the healthcare system. In 2014, 97.33% of RCSs were performed in Italian public hospitals and 2.67% in the private healthcare system [9]. In 1998, 91% of rotator cuff repairs were performed in Finnish public hospitals and 9% in private hospitals, but in 2011, the corresponding percentages were 53% and 47% [14]. In Chile, the rate in the private healthcare system is triple the rate in the public healthcare system for RCS. This difference is probably related to the patient’s capability to assume costs and access compared with the public healthcare system. The lower rates of RCS in the public sector could be explained by its shortage in coverage in terms of number of healthcare professionals per patient and concordantly the long waiting lists associated to this fact. Moreover, seek care in the private system without a proper coverage comes with a high out of pocket cost which limits public to private transfer of patients.
Nonetheless, the public system RCS rates increased at a higher pace than private RCS rates, observing a decrease in the difference at the end of the studied period (2018). In an attempt to explain this finding, we hypothesize that this may be due to: 1) an improvement in the public healthcare system surgical capacity, 2) an increase in the state budget for the health sector, and/or 3) the implementation of new OOPS to access for RCS in the public health system.
Chilean citizens had a high level of OOPS and segmentation of private and public insurance schemes. The OOPS as a share of total health expenditure is 33% which is one of the highest among OECD countries (OECD average of 20%). The new OOPS payment or “Payment Associated to Diagnosis” (PAD) allows patients to pay an affordable, known and fix amount to access to pre-stablished medical benefits depending on each diagnosis. This amount corresponds to 50% of the total amount received by the private institution that will provide health care (in this case RCS). The other 50% is covered by the state and is transferred directly to a private institution that must be affiliated to this system. As the amount paid per patient is fix, there are no subsequent modifications allowed in the total price independently from the number of implants used, bed days, medications, exams, and other supplies needed to carry out the procedure [17].
One of the main strengths of this study is the use of a large sample size based on a nationwide database of public information that must be compulsorily recorded in all surgeries of public and private institutions. Because the information is collected from all regions of Chile, the data are expected to be representative of the country. To our knowledge, this is the first study in Chile that reports RCS rates and analyzes its associated factors and differences with previously reported data from other countries.
One of the main limitations is the retrospective design, which can influence the recording and coding of the information. By including three different codes, it is expected to cover the greatest number of accurate diagnoses. However, we recognize that subjects may be excluded or incorrectly included we are unable to evaluate potential inaccuracies in the coding of the diagnoses. Nonetheless, we believe that our results highlight important trends in RCS.