Anatomical reconstruction of the knee extensor apparatus for prepatellar myxofibrosarcoma

A novel reconstruction of the knee extensor apparatus was attempted in a 69-year-old patient with prepatellar myxoid fibrosarcoma. The skin (35×25 cm), subcutaneous tumor, quadriceps tendon, patella, anterior capsule, and patella tendon were widely resected en-bloc. Following wide resection, the excised quadriceps tendon, patella, and patella tendon were anatomically reimplanted into the original site after being devitalized in liquid nitrogen. These complexes were covered by a free vascularized latissimus dorsi myocutaneous flap. At 18-month follow-up, the strength of active knee extension was 4+ of 5 in the muscle manual test. The active range of motion was 110° in flexion and -10° in extension. The tumor showed no evidence of disease. The patella and femur joint showed no osteoarthritis on plain radiographs. This procedure is the only way to achieve anatomical reconstruction. Reattachment of patella tendon to the tibial tuberosity was possible. The use of liquid nitrogen to devitalize is straightforward and the operation time can be shortened. To our knowledge, this type of reconstructive procedure has never been reported in the English literature.