Askilled walker adopts the pattern to assist the full range of leg motion. in this pattern, the knee extends at heel strike, flexes slightly as the body weight moves forward over the supporting leg, then extends once more at foot push-off.

Double knee-lock.

Explanation:

Knee lock may be defined as the problems that are generally associated with the knee joint problems. The knee lock causes pain and limits the position.

Double knee lock assist the full range of the motion of the leg. The knee extends in the double knee lock and heel strike that flexes the legs and extends the foot push-off.

Thus, the answer is double knee lock.