Should there be X-ray evidence of Medial Patellofemoral Ligament (MPFL) reconstruction 2 weeks post-operative (post-op)?

X-ray Evidence of MPFL Reconstruction at 2 Weeks Post-Op

X-ray evidence of Medial Patellofemoral Ligament (MPFL) reconstruction is not typically visible or expected at 2 weeks post-operative as this is primarily a soft tissue procedure.

Radiographic Expectations After MPFL Reconstruction

• Standard post-operative radiographs are generally not necessary after uncomplicated MPFL reconstruction at the 2-week mark, as they have low yield for detecting complications in the immediate post-operative period 1
• MPFL reconstruction involves soft tissue grafting that is not directly visible on plain radiographs, though the anchors or fixation hardware may be visible depending on the technique used 2
• Routine immediate post-operative radiographs are considered unnecessary unless the surgery was complicated or there are specific clinical indications warranting imaging evaluation 1

Expected Findings on Early Post-Op Imaging

• If radiographs are obtained, they may show:
  • Femoral fixation hardware (typically an interference screw in a blind tunnel between the adductor magnus tubercle and the medial epicondyle) 2
  • Patellar fixation hardware (typically anchors at the superomedial border of the patella) 2, 3
  • Possible soft tissue swelling 1
• However, the MPFL graft itself (typically gracilis tendon) will not be visible on plain radiographs 2

When Early Post-Op Imaging Is Indicated

• Radiographs at 2 weeks post-op would only be indicated if there are clinical concerns such as:
  • Suspected periprosthetic fracture 1
  • Significant pain inconsistent with normal post-operative course 1
  • Suspected hardware complications 1
  • Abnormal clinical findings suggesting patellar maltracking or instability 1

Longer-Term Radiographic Assessment

• More meaningful radiographic assessment typically occurs at longer follow-up intervals:
  • Reduction in patellar tilt can be measured on radiographs and is a significant finding after successful MPFL reconstruction 2
  • Correction of patella alta may be observed on later follow-up radiographs (6 months) as measured by Insall-Salvati ratio, Caton Deschamps index, and Blackburne-Peel ratio 4
  • Femoral tunnel position can be assessed radiographically to ensure proper placement (ideally 40% from posterior, 50% from distal, and 60% from anterior border of the medial femoral condyle) 3

Clinical Implications

• Early rehabilitation should focus on range of motion and quadriceps activation rather than radiographic appearance 1
• Isometric quadriceps exercises including static contractions and straight leg raises can be safely prescribed during the first 2 post-operative weeks 1
• Early mobilization can improve early phase knee flexion and extension range of motion without compromising stability 1

Common Pitfalls to Avoid

• Overreliance on early radiographs to assess surgical success when clinical examination is more valuable at this stage 1
• Misinterpreting normal post-operative changes as complications 1
• Failing to recognize that the primary goal of MPFL reconstruction is to restore patellar stability and normal kinematics, which cannot be adequately assessed on early post-operative radiographs 5
• Expecting to see changes in patellar height or tilt on early radiographs when these changes typically develop over time 4

In conclusion, while hardware components may be visible, the actual MPFL reconstruction itself is not expected to show specific radiographic evidence at just 2 weeks post-operative, and routine radiographs at this time point are generally not indicated unless there are specific clinical concerns.