*4.10.1 Step 1: Patient Preparation and Diagnostic Arthroscopy*

The patient is placed in the supine position. Using a surgical marking pen, the skin incisions and anatomical landmarks (i.e. the medial two-thirds of the patellar border, the pes anserinus, adductor tubercle, and medial femoral epicondyle) are marked as shown in **Figure 6**. After the induction of general anesthesia, the patient is examined for range of motion and the presence of 4-quadrant translation of the patella with minimal force applied. After performing the examination under anesthesia, the patient is prepped and draped in a sterile fashion. Using standard anterolateral and anteromedial portals, diagnostic arthroscopy of the affected knee is undertaken. Arthroscopic chondroplasty is performed if the patient has significant chondromalacia of the patellofemoral joint.

#### **Figure 6.**

*Patient is placed in the supine position with the left knee in 45° of flexion providing an anteromedial view of the knee. Using a surgical marking pen, the anatomical landmarks are drawn. First, the medial border of the patella (MBP) is palpated and the proximal two-thirds is marked. The pes anserinus (PA) is marked at the anteromedial border of the proximal tibia. On the medial aspect of the knee, the adductor tubercle (AT) can be palpated just distal to the medial femoral epicondyle (ME). Proper identification of these anatomical landmarks is essential to performing this MPFL reconstruction with relative ease. Reproduced with permission from: Kurowicki et al. [130].*
