The case is a 70-year-old female with a history of left ankle torsion one month before but progressively soft tissue swelling of the ankle more prominent in lateral malleolus side. Based on the clinical findings left ankle MRI without gadolinium injection was requested and intrasubstance tear of both peroneal longus and peroneal brevis tendons with tenosynovial sheath tear and remarkable fluid in tendon sheath and also remarkable lateral malleolus soft tissue swelling and oedema and bruise in lateral malleolus bone were found. 

The concomitant tear of the peroneal longus and peroneal brevis tendons is a rare event but can cause ankle instability and vice versa and also chronic pain in the lateral ankle joint. The imaging modality of choice for diagnosis and grading the tendons tear is performing MRI with ankle protocol and the best treatment in isolated or concomitant cases is surgical allograft repair.