Ceratophrys cranwelli, commonly known as the Cranwell’s horned frog or Pacman frog, is an amphibian species native to South America. This species has gained interest both as a pet among hobbyists and as a subject of scientific inquiry in veterinary medicine. A two-year-old pet male albino Ceratophrys cranwelli was presented exhibiting lethargy, weight loss, and anorexia, persisting for two months. Clinical examination revealed a fracture localized to the proximal third of the left femur accompanied by an osteolytic process. The patient was discharged with a treatment regimen for suspected secondary nutritional hyperparathyroidism and an ulcerative skin lesion. Nevertheless, due to the progressive deterioration of the left thigh, amputation of the affected limb was proposed and performed at the coxofemoral joint. Histopathological analysis of the excised mass revealed an atypical mesenchymal mass consistent with a fibromyxochondroma. The surgical procedure was conducted under anesthesia induced by a combination of alfaxalone, ketamine, medetomidine, and butorphanol, with postoperative treatment consisting of enrofloxacin, meloxicam, and butorphanol. The patient showed good post-surgical recovery, exhibiting normal physiological and behavioral activities. This report highlights the management and the diagnostic challenges of a progressive limb lesion in a Ceratophrys cranwelli, offering insights into potential therapeutic approaches for similar cases in amphibians.