Clinical features and early warning factors of symptomatic pulmonary embolism after total joint arthroplasty: a retrospective cohort study

Background Symptomatic pulmonary embolism (PE) is a severe and life-threatening complication following total joint arthroplasty (TJA). Despite advances in diagnosis, treatment, and prediction, postoperative PE still occurs. This study aimed to investigate the onset time window, initial clinical presentations, and preoperative comorbidity profiles of patients with symptomatic PE after TJA, thereby providing clinical evidence for early identification and perioperative management of post-TJA PE. Methods In this retrospective study, patients who underwent TJA at our institution between January 2023 and December 2025 and were diagnosed with postoperative PE via computed tomography pulmonary angiography were assigned to the case group. Non-PE patients were randomly selected at a 1:2 ratio as controls. Data collected included baseline patient characteristics, surgical procedure, time from surgery to PE onset, chief complaints at onset, BMI, and preoperative comorbidities. Age-stratified analyses were conducted to compare symptom distributions. Multivariable logistic regression was then performed to evaluate the associations between physiological parameters, chief complaints, and PE at onset, and the diagnostic performance of identified warning factors was calculated. Results A total of 5,120 patients who underwent TJA were evaluated. Symptomatic PE was diagnosed in 84 patients (1.64%), with a mean age of 67.4 ± 8.8 years. Among these, 73 underwent total knee arthroplasty (TKA) and 11 underwent total hip arthroplasty (THA). The mean time from surgery to PE onset was 51.8 ± 26.1 h, with 72 cases (85.7%) occurring within 72 h postoperatively. No significant differences in preoperative comorbidities were observed between the two groups ( P > 0.05). At PE onset, pulse oxygen saturation (SpO 2 ) monitoring revealed decreased SpO 2 in 78 patients (92.9%). The most common presenting symptoms were respiratory manifestations ( n = 48, 57.1%), followed by altered mental status ( n = 22, 26.2%), precordial discomfort ( n = 12, 14.3%), chills and fever ( n = 8, 9.5%), fatigue ( n = 7, 8.3%), and headache or dizziness ( n = 4, 4.8%). Age-stratified analyses revealed significant differences in the distribution of SpO 2 , respiratory symptoms, and altered mental status ( P < 0.05). Multivariable logistic regression identified lower levels of SpO 2 (OR = 0.668, 95% CI: 0.599–0.745) as being independently associated with PE, while respiratory symptoms (OR = 16.448, 95% CI: 5.408–50.029) and altered mental status (OR = 5.828, 95% CI: 1.485–22.879) were established as independent predictors. The combined early recognition model incorporating these three parameters demonstrated an area under the receiver operating characteristic curve (AUC) of 0.966 (95% CI: 0.947–0.984), exhibiting superior warning performance compared to any single indicator. Conclusion Post-TJA PE predominantly occurs within 72 h postoperatively. Decreased SpO 2 , respiratory symptoms, and altered mental status serve as early warning signs, with a combined early recognition model demonstrating superior warning performance compared to any single parameter. Early postoperative vital sign monitoring and recognition of age-related atypical symptoms should be enhanced to improve the early identification and management of PE.