Fig. 4From: Gradual loaded exercise of knee extension muscles using an orthosis after wide resection of a femoral sarcoma and quadriceps muscle: a case reportRigid knee orthosis with dual-adjustable lock knee. a Fully extended fixed knee. b Range 0°–30°, which allowed 0°–30° of knee range of motion (ROM). c Free range (no limitation of knee ROM)Back to article page