Acute traumatic fracture of the medial coronoid process is rarely reported and has previously only been described in three dogs to date. A three-year-old Schapendoes was presented for an acute non weight-bearing lameness. The definitive diagnosis of a medial coronoid process fracture was delicate and based on the disto-medial proximo-lateral oblique radiographic view (Di35M-PrLO). The surgical removal of the fragment was performed using a medial arthroscopic approach. The outcome was rapidly favourable. Lameness disappeared and the follow-up radiographs three months later revealed minimal reactions of osteoarthrosis.