CPT® Code 0594T

Osteotomy, humerus, with insertion of an externally controlled intramedullary lengthening device, including intraoperative imaging, initial and subsequent alignment assessments, computations of adjustment schedules, and management of the intramedullary lengthening device

The procedure described by CPT® Code 0594T involves an osteotomy of the humerus, which is a surgical operation that entails cutting the bone to correct deformities or to facilitate limb lengthening. This specific procedure utilizes an externally controlled intramedullary lengthening device, which is implanted within the medullary canal of the humerus. The device is designed to gradually lengthen the bone through a process known as distraction osteogenesis, where the bone is slowly separated to allow new bone tissue to form in the gap created. This technique is particularly beneficial in cases of trauma or congenital deformities, providing a method for limb reconstruction. The average duration for the lengthening process is approximately 70 days, with a typical distraction rate of 0.72 mm per day, translating to about 13 days for each centimeter of lengthening. Different methods can be employed for the insertion of the lengthening device, including antegrade and retrograde approaches, which may utilize either electromotorized or magnetically activated devices. The antegrade approach involves making an incision on the anterolateral aspect of the shoulder to access the humeral canal, while the retrograde approach, which is often preferred for its protective benefits to the rotator cuff, requires the patient to be positioned supine with the elbow flexed. In both approaches, careful dissection and the use of protective sleeves are critical to ensure the integrity of surrounding soft tissues and to facilitate the osteotomy. Postoperatively, the lengthening process is initiated within 5 to 8 days, utilizing an external controller to manage the rate of distraction, while ongoing assessments and adjustments are made to ensure proper alignment and device function throughout the lengthening period.