Upper extremities sarcoma poses a major challenge due to its complex anatomy for safe oncological clearance and high functional demand. The posterior compartment of the arm consists of the triceps brachii muscle, which has three origins. All three heads merge together to form a single tendon, inserted at the olecranon process. The oncological anatomical boundaries for resection are not well defined. In high-grade sarcoma, complete compartment resection is an option for adequate oncological clearance.