A recent study has found that obese patients undergoing elective shoulder replacement surgery do not face an increased risk of death or complications. Conducted by Epaminondas Markos Valsamis and colleagues from the University of Oxford, the research was published in the open-access journal PLOS Medicine in March 2025. This finding challenges the prevailing view that higher body mass index (BMI) should exclude patients from these procedures.
Joint replacement surgeries, which include hip, knee, and shoulder replacements, are known to significantly enhance the quality of life for individuals suffering from joint issues. Yet, many patients classified as obese have been denied access to these surgeries, often based on outdated or unclear guidelines from health organizations. The current evidence surrounding the risks faced by obese patients during joint replacement surgeries is limited and inconsistent.
To investigate this further, Valsamis and his team analyzed data from over 20,000 elective shoulder replacement surgeries across the UK and Denmark. They aimed to determine whether BMI was correlated with post-surgery outcomes, including mortality and other complications. Surprisingly, they discovered that patients with obesity, defined as a BMI of 40 kg/m², had a 60% lower risk of death within one year following surgery compared to those with a healthy BMI of 21.75 kg/m². Additionally, patients classified as underweight, with a BMI of less than 18.5 kg/m², exhibited a slightly higher risk of death.
These results raise important questions about the criteria used to restrict access to elective surgeries. The study’s findings suggest that denying surgery to patients with a high BMI is unwarranted and may not align with the evidence.
Implications for Patients and Healthcare Providers
Despite its significant conclusions, the study acknowledges a limitation: the small sample size of the underweight population, which included only 131 patients from the UK and 70 patients from Denmark. Nonetheless, the comprehensive nature of the study consistently highlighted a lower risk of death and complications among obese patients undergoing shoulder replacement surgeries across various outcomes.
The implications of this research are substantial for patients, surgeons, and policymakers aiming to make informed decisions about surgical eligibility. Professor Jonathan Rees, the senior author of the study, emphasized the importance of re-evaluating the use of BMI thresholds that have historically limited access to joint replacement surgeries. He stated, “While BMI thresholds have been used to limit access to joint replacement surgery, our findings do not support restricting higher BMI patients from accessing shoulder replacement surgery.”
The research underscores the potential of shoulder replacements to provide significant pain relief and improve the quality of life for many patients. The lead author, Epaminondas Markos Valsamis, remarked, “Shoulder replacements offer patients the opportunity for excellent pain relief and improved quality of life. Our research shows that patients with a higher BMI do not have poorer outcomes after shoulder replacement surgery.”
In conclusion, this study contributes valuable insights into the safety of shoulder replacement surgeries among obese patients. It challenges existing biases and advocates for a more inclusive approach to surgical eligibility, potentially transforming the landscape of joint replacement surgery for individuals who may have been previously overlooked.