A back brace has a lumbar support that is split into upper and lower sections that are connected to a flexible joint, allowing the lumbar support to bend towards the spine of the user to help provide additional lumbar support. The lumbar support is also generally split into left and right sections that cause the upper and lower sections to bend when the left and right sections are drawn together. Usually, the left and right sections are drawn together using a pully mechanism.一背部護具具有一腰椎支撐件，其分成上端部份及下端部份，與一具彈性的接合件相連接，使腰椎支撐件能沿使用者的脊椎曲線彎曲，以提供腰部一額外的支撐力。腰椎支撐件大致上分成左半部份及右半部份，當左半部份及右半部份同時被拉動時，即促使上端部份及下端部份彎曲。通常，左半部份及右半部份以一滑輪機制被同時拉動。
