How to Use Full-Length Standing Radiographs to Measure Posterior Tibial Slope and Anterior Tibial Translation

Area of Science:

• Orthopedic surgery
• Radiology
• Biomechanics

Background:

• Increased posterior tibial slope (PTS) and anterior tibial translation (ATT) are associated with higher failure rates in anterior cruciate ligament reconstruction.
• Accurate measurement of PTS and ATT is vital for effective surgical planning in patients undergoing knee surgery.
• Full-length weightbearing lateral tibial radiographs offer superior accuracy for PTS and ATT measurement compared to other imaging modalities.

Purpose of the Study:

• To present a validated and reproducible stepwise technique for the accurate measurement of PTS and ATT.
• To provide a precise radiographic method to aid in surgical planning for knee ligament reconstruction.

Main Methods:

• Utilizes full-length weightbearing lateral tibial radiographs for measurement.
• Defines specific landmarks and lines to calculate PTS by measuring the angle relative to the tibial plateau.
• Defines specific landmarks and parallel lines to calculate ATT by measuring the distance between tibial and femoral diaphyses.

Main Results:

• The described technique yielded a posterior tibial slope (PTS) of 14.2°.
• The technique measured an anterior tibial translation (ATT) of 12.6 mm.
• The measurements were obtained using the validated radiographic technique.

Conclusions:

• The presented technique provides an accurate and reproducible method for measuring PTS and ATT using weightbearing lateral radiographs.
• This radiographic technique offers greater precision than alternative imaging modalities for assessing PTS and ATT.
• Accurate PTS and ATT measurements derived from this technique offer direct benefits for surgical planning in orthopedic knee procedures.