**4.3 Investigations**

It is very hard to diagnose PCL stump impingement clinically as the symptoms are not usually typical. Special scans like MRI and CT scans are also of limited value due to their scatter and artifacts associated with metallic implants. However, arthroscopy has an important role in this with regards to both diagnostic and therapeutic significance. If an arthroscopy is performed in these patients, it is recommended a complete inspection of the joint including the posterior compartments as is done in non-TKA patients with posterior knee pain.
