Gradual loaded exercise of knee extension muscles using an orthosis after wide resection of a femoral sarcoma and quadriceps muscle: a case report.

BACKGROUND: Details of improved gait ability after wide resection of soft tissue sarcomas that necessitate removal of portions of the quadricep muscle have not yet been reported. We describe a patient with improved gait ability following a rehabilitation program after wide resection of a soft tissue sarcoma that included four components of the quadricep muscle. CASE PRESENTATION: An 85-year-old Japanese man underwent wide resection of an undifferentiated pleomorphic sarcoma that included portions of the quadriceps femoris muscle. The rectus femoris, vastus medialis, sartorius, and vastus intermedius were separated in the maximally bulging region of the tumour. Three weeks postoperatively, gait exercise was initiated using a rigid knee orthosis with a dual-adjustable lock knee. The contraction loading of the knee extension muscle was controlled by adjusting the hinge motion range of the orthosis as follows: fully extended, fixed knee 0°-30°, and free range. Under this regimen, he could walk independently without a rigid orthosis within 5 weeks postoperatively but could not sit on his heels during daily living activities. At six months, there was no clinical evidence of recurrent tumours or complications. CONCLUSIONS: Postoperative gait ability might be affected by not only the number of resected muscles but also by the function of the separated muscles and the cross-sectional area of the remaining muscle. Gradually loaded exercise of the knee extension muscles using an orthosis could result in an improved gait motion for patients who undergo wide resection of a sarcoma that includes four components of the quadriceps femoris.