A comparison between the transpatellar tendon and the lateral approach to the knee joint during arthroscopy. A cadaver study.

The cental transpatellar tendon arthroscopic approach and the standard lateral approach were compared in 200 unselected cadaver knees. A 5-mm arthroscopic dummy was used in the investigation. In 198 knees, using the transpatellar tendon approach, the dummy passed through the infrapatellar fat pad. In 7 cases with the transpatellar approach and in 22 cases with the lateral approach, we were unable to reach the medial posterior compartment of the knee joint. It was usually easier to insert the arthroscopic dummy into the posterior fossa if the knee joint was held at 35 to 40 degrees of flexion of the knee than at 90 degress of flexion. In 88 of 100 knees, the dummy could be passed from the transpatellar approach into the lateral posterior fossa and in 77 of 100 knees from the lateral approach. Patella baja was found in 16 knees (8%). Since the transpatellar tendon approach should not be used in these cases, it means that this technique cannot be used in all cases. From an anatomical point of view, the transpatellar tendon method thus does not offer any major advantages compared to the standard lateral one.