In lower-limb pathomechanical patient populations, one of the greatest impediments to energy-efficient ambulation is the development of a genu recurvatum deformity. When this deviation occurs, the thigh and lower limb segments move posteriorly in direct opposition to the anterior advancement of the proximal body mass over the fixed distal base of support. Genu recurvatum usually is an acquired deformity secondary to changes of the distal skeletal joint alignments and compensatory movement patterns. The alignment of the distal base of support determines the load bearing and functional motion available to the proximal knee joint during ambulation and can serve either to promote or disrupt the required sagittal plane limb advancementThis article describes three distinct pathomechanical profiles of posterior knee joint deviation in relation to the primary planes of motion. The distinction between an initial hyperextension moment and an acquired recurvatum deformity is presented in terms of predictability, prevention and correction of joint deformation. Gait training and orthotic design criteria are discussed as they relate to a comprehensive rehabilitation program to maximize both structural and functional outcomes for patients with lower-limb instabilities and deformities