The lower extremity refers to the part of the body from the hip to the toes.
Many people refer to the lower extremity as the leg.
In fact, the leg is the part of the body between the knee and ankle joints.

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The proper way to describe the lower limb is the lower extremity.This may seem like a minor detail.
In anatomic terms, the body is described as follows.
Molina CS, Faulk JB.Lower extremity amputation.
Maduri P, Akhondi H.Upper limb amputation.
Waheed SM, Hotwagner DT.Deep vein thrombosis (DVT).
Lezak B, Massel DH, Varacallo M.Peroneal (fibular) nerve injury.
Wong M, Kiel J.Anatomy, bony pelvis and lower limb, Achilles tendon.