Bilateral total knee replacement: staging and pulmonary embolism.

Area of Science:

• Orthopedic Surgery
• Cardiovascular Health
• Health Services Research

Background:

• Uncertainty exists regarding optimal timing for bilateral total knee replacement: simultaneous or staged procedures.
• Limited national data available on the comparative risks, particularly pulmonary embolism, of these approaches.

Purpose of the Study:

• To compare the risk of symptomatic pulmonary embolism in patients undergoing simultaneous bilateral total knee replacement versus staged or unilateral procedures.
• To identify factors associated with simultaneous versus staged bilateral total knee replacement.

Main Methods:

• Retrospective review of 122,385 US Medicare enrollees who underwent total knee replacement in 2000.
• Analysis included patient demographics, comorbidities, hospital/surgeon volume, and procedure timing (simultaneous, staged, unilateral).
• Calculated the probability of symptomatic pulmonary embolism within three months post-surgery for each procedure type.

Main Results:

• Simultaneous procedures were more common with high-volume hospitals and surgeons, and in men.
• The risk of pulmonary embolism within three months was 1.44% for simultaneous procedures versus 0.81% for single procedures.
• Adjusted hazard ratio for pulmonary embolism was 1.81 (95% CI, 1.49-2.20) for simultaneous procedures compared to single procedures.

Conclusions:

• Significant differences exist in patient and procedural characteristics between simultaneous and staged bilateral total knee replacement recipients.
• The adjusted risk of pulmonary embolism is approximately 80% higher in the three months following simultaneous total knee replacement compared to a single procedure.
• The cumulative risk of staged procedures may equal or exceed that of simultaneous bilateral total knee replacement.