Recommended Follow-Up Care for Asymptomatic Total Knee Arthroplasty
For an asymptomatic patient with prior total knee arthroplasty showing no acute abnormality, routine follow-up with standing knee radiographs (AP, lateral, and axial patellofemoral views) should be performed every 1-2 years and continued long-term for over 10 years. 1
Imaging Protocol for Routine Follow-Up
Standard Radiographic Views
- Standing anteroposterior (AP) and lateral views plus a tangential axial view of the patellofemoral joint constitute the routine examination 1
- Weight-bearing positioning is mandatory, as non-weight-bearing films underrepresent alignment issues 2
- Some practitioners also obtain standing long-leg (hip-to-ankle) views for optimal alignment assessment, though standard AP knee radiographs are valid alternatives for determining coronal plane alignment after a baseline hip-to-ankle film is obtained 1, 2
Technical Considerations
- AP views obtained with 10° internal rotation improve interpretation of varus and valgus alignment compared to neutral positioning 1, 2
- Annual weight-bearing radiographs are recommended for detecting subclinical polyethylene wear, which appears as joint space narrowing 1, 2
Follow-Up Frequency
Evidence-Based Timing
- 80% of American Association of Hip and Knee Surgeons members recommend annual or every-other-year orthopedic and radiographic examinations 1, 2
- This schedule should continue for the long term (>10 years) 1, 2
- More frequent follow-up is warranted if there are signs of failure or sepsis, subnormal periprosthetic bone quality, or history of prior revision 1
Rationale for Serial Imaging
Serial radiographs are critical for identifying subtle interval changes, particularly loosening, osteolysis, and component wear 1, 2
What Not to Do
Avoid Unnecessary Immediate Postoperative Imaging
- Routine immediate postoperative or recovery room radiographs are unnecessary unless surgery was complicated or specific clinical indications exist 1
- Multiple studies of over 5,000 patients found that immediate postoperative radiographs altered management in fewer than 0.01% of cases 1
- If satisfactory baseline in-hospital radiographs were obtained, repeat routine radiographs at the initial follow-up visit are unnecessary 1
Inappropriate Imaging Modalities for Asymptomatic Follow-Up
The ACR Appropriateness Criteria rates the following as "usually not appropriate" (rating 1/9) for asymptomatic TKA follow-up: 1
- MRI (with or without contrast)
- CT
- Fluoroscopy
- Ultrasound
- Nuclear medicine studies (bone scan, WBC scan, FDG-PET/CT)
- Arthrography
- Image-guided aspiration
Clinical Monitoring Beyond Imaging
When to Increase Surveillance
Patients should be monitored more closely and potentially imaged more frequently if they develop: 1
- New pain or functional limitations
- Signs of infection
- Decreased periprosthetic bone quality
- History of prior revision surgery
Patient Education
Emphasize the importance of adherence to follow-up visits, as studies show declining attendance rates (61% at 1 year, 25% at 4 years), particularly in younger patients (<65 years), those with higher ASA classifications, and those living closer to the hospital 3
Key Pitfall to Avoid
Never obtain radiographs in the supine position for TKA follow-up, as this significantly underrepresents alignment abnormalities and component positioning issues. 2 All follow-up radiographs must be weight-bearing to accurately assess functional alignment and detect early complications like polyethylene wear or component loosening.