Primary Leiomyosarcoma of Humerus Presenting with Pathological Fracture and Treated Initially with Inadvertent Plate Fixation: a Case Report with Literature Review

Leiomyosarcoma is a malignant tumor of smooth muscle origin and commonly diagnosed in the uterus, gastrointestinal tract, and mucous membranes or as metastasis to the skeletal system. Primary leiomyosarcoma of bone is an uncommon type of tumor. Patient with primary bone sarcoma may present with a pathological fracture following a trivial injury, resulting in pain, swelling, and deformity. The pathological fracture needs to be evaluated with a high index of suspicion and proper investigations must be performed prior to fracture fixation. We present a case of primary leiomyosarcoma of humerus, who presented as pathological fracture and underwent inadvertent plating at a peripheral hospital. We treated this patient with wide resection of the tumor and the reconstruction was performed with an implant (Kuntscher’s nail and extra-articular plate) with bone cement spacer. The use of this novel method allowed us to perform implant fixation with small distal humerus bone segment and preserve native elbow joint. In this case report, we aim to highlight the importance of thorough preoperative evaluation and keeping a high index of suspicion while dealing with suspected pathological fractures to differentiate between primary and metastatic disease.