CPT® Code 27638

The CPT® Code 27638 refers to the excision or curettage of a bone cyst or benign tumor located in the tibia or fibula, specifically when the procedure involves the use of an allograft. A bone cyst is defined as a fluid-filled space within the bone, which can vary in type and presentation. One of the most common forms is the unicameral or simple bone cyst, recognized as a benign lesion. Another type, the aneurysmal bone cyst, is characterized by vascular tissue that surrounds a blood-filled cystic lesion. Additionally, there are various benign bone tumors, including giant cell tumors, chondromyxoid fibromas, and enchondromas, which may necessitate surgical intervention. During the procedure associated with this code, an incision is made over the lesion site in the tibia or fibula, allowing for the dissection of soft tissues to expose the lesion. If a cystic lesion is identified, the bone is incised to create a window, enabling access to the cyst. The fluid within the cyst is aspirated for laboratory analysis. A curette is then utilized to remove the lining of the cystic cavity completely. In cases where benign tumors are present, the lesion is excised along with a margin of healthy bone. Following the excision or curettage, the defect created in the bone is filled with donor bone, known as an allograft, to promote healing and structural integrity of the bone. This procedure is critical for addressing bone cysts and benign tumors while ensuring proper recovery and function of the affected limb.