A total of 155,022 patients were identified, of which 150,581 underwent unilateral TKA and 4441 underwent SBTKA. The SBTKA group was found to be at a higher risk of venous thromboembolism (VTE), bleeding, and composite morbidity. Stratification analysis revealed that SBTKA subgroups at higher risk of VTE include patients of black or Asian origin, obese patients, and those who underwent anesthesia other than general or spinal/epidural. SBTKA subgroups at higher risk of bleeding include patients older than 85 years, those with race other than white, underweight and obese patients, and patients who underwent anesthesia other than spinal/epidural. Although none of the subgroups were protected from bleeding, patients who underwent spinal/epidural anesthesia had a lower risk of bleeding compared to other types of anesthesia.