The prone position is among the many positions used during various neurosurgical and orthopedic surgeries (posterior fossa tumors and spine). Complications associated with prone positioning include stroke, upper airway obstruction, endotracheal tube dislodgement and brachial plexus injury, among others. Arterial cannula displacement during positioning or in the middle of an ongoing major surgery is a nightmare to anesthesiologists, due to difficulties of accessing commonly used arteries for arterial cannulation. It becomes even more challenging when the extremities are not available for cannulation in patients with polytrauma. The popliteal artery can be a very useful option in this situation. Point-of-care ultrasonography (POCUS) has made vascular structures easily accessible for diagnostic and therapeutic purposes, which were previously impossible with blind techniques [1,2]. POCUS can be an invaluable tool for popliteal artery cannulation due to its deeper location and presence of the popliteal vein above it [3].Written informed consent obtained from the patient. A 60-year-old woman with history of fall from a 6-m height was scheduled for pedicle screw fixation of L1 vertebral fracture. She also had bilateral upper limb fractures along with right metatarsal fracture. She was known to be diabetic and hypertensive with irregular medications. Due to intraoperative hemodynamic instability and difficulty of measuring noninvasive blood pressure, arterial cannulation (over the needle technique) was performed in the left dorsalis pedis artery. During the intraoperative period, the arterial cannula was displaced, as indicated by damping in the arterial wave tracing. After repeated failed attempts to cannulate the left posterior tibial artery, we decided to cannulate the left popliteal artery. The left popliteal fossa was cleaned and draped. An ultrasound image of the popliteal artery with the vein lying above and the nerve bundle below was obtained (Fig. 1A). Colored Doppler was used to improve identification of the artery. The artery was found just below the vein from the roof of the popliteal fossa. Hence, it could not be punctured perpendicularly. The vein was to be bypassed by puncturing the artery from the medial or lateral side using the Seldinger technique (Fig. 1B).The popliteal artery is accessed in the popliteal fossa, which is bound by the biceps femoris, plantaris, and lateral head of the gastrocnemius laterally and by the semitendinosus, semimembranosus, and medial head of the gastrocnemius medially. The floor is formed by the knee joint, and the roof is formed by the skin, subcutaneous, and fascia lata [2]. The popliteal artery has an average diameter of 7.4-9.5 mm [3]. The popliteal artery and vein are present in the common sheath, and the vein crosses the artery from the lateral to medial as we move from above to below. Easy accessibility in the prone position, reliable anatomy, and large diameter were advantages of popliteal artery cannulation. However, because of its deep location and adjacent placeme...