Background: The purpose of this study was to analyze a series of
patients with a high-grade metaphyseal osteosarcoma of the knee who had been
treated with a transepiphyseal resection, with preservation of the distal
femoral and the proximal tibial (articular) portions of the epiphysis, and an
intercalary allograft reconstruction.
Methods: The cases of thirteen patients with a high-grade
metaphyseal osteosarcoma around the knee who had transepiphyseal resection and
reconstruction with an intercalary allograft were retrospectively reviewed at
a mean of sixty-three months. Complications, disease-free survival of the
patient, final preservation of the limb and epiphysis, and functional results
according to the Musculoskeletal Tumor Society scoring system were documented
at the time of the latest follow-up.
Results: At the final follow-up examination, eleven of the thirteen
patients continued to be disease-free. One patient died of bone and pulmonary
metastases with no evidence of local recurrence, and the remaining patient had
no evidence of disease after resection of a local recurrence of the tumor in
the soft tissues. No patient had a local recurrence in the remaining
epiphysis. Seven patients had complications that included a fracture (three
patients), diaphyseal nonunion (two), deep infection (one), and a local
recurrence in the soft tissues (one). The allograft was removed in only four
of these patients. At the latest follow-up examination, twelve patients were
alive with preserved limbs. In one patient, the epiphysis, which originally
had been preserved, was resected because of a metaphyseal fracture, and the
limb was reconstructed with an osteoarticular allograft. The patients with a
preserved epiphysis had an average functional score of 27 points (maximum, 30
points).
Conclusions: Preservation of the epiphysis in high-grade metaphyseal
osteosarcoma at the knee is an alternative in carefully selected patients.
Crucial factors needed to obtain local tumor control and achieve an acceptable
functional result are a positive response to chemotherapy, accurate
preoperative assessment of tumor extension to the epiphysis, and appropriate
fixation techniques for intercalary allografts.
Level of Evidence: Therapeutic study, Level IV (case
series [no, or historical, control group]). See Instructions to Authors for a
complete description of levels of evidence.