In this case report, the presence of a fragmented coronoid process in a 10-year-old male Belgian shepherddog is described. The signalment is atypical, since the disease mostly affects young dogs, and it lessfrequently occurs in Belgian shepherd dogs. The dog was presented with unilateral lameness of the leftfront limb, which had gradually worsened in the course of nine months. Further orthopedic and radiographicexaminations revealed a defi nitive diagnosis of a fragmented coronoid process. Except for anabnormal form of the medial coronoid process and severe osteosclerosis, there was only a mild osteoarthrosis,which is not expected in an old dog with a chronic problem. Moreover, it was a unilateral problem,whereas a fragmented coronoid process is frequently presented as a bilateral disorder. Using arthroscopy,the joint was inspected and the loose fragment was successfully removed. Mostly, older animals remainlame after the procedure, but in this case, the procedure yields an obvious clinical improvement, and thedog was clearly improved.