Patent ID: 8167956

Claim:
A prosthetic foot ( 1 ) in the form of a composite material lamina with a characteristic J-shape, fixable by a TT bracket ( 2 ) directly to a socket ( 3 ) containing the stump, i.e. the residual part of the amputated lower limb, in the case of users with transtibial amputations, or fixable by a TF bracket ( 2 a ) to a mechanical knee (G), itself fixable to a socket ( 3 a ), in the case of users with transfemoral amputations, said socket ( 3 or 3 a ) having a main axis ( 5 ) which coincides with the loading straight line during static alignment and during mid-stance, said loading straight line being that along which the user, after applying the prosthesis, discharges body weight in the static position, the main axis ( 5 ) passing through a point ( 4 ) identifying the femoral epicondyle, real in the case of transtibial users and virtual and representative of the centre of rotation of the mechanical knee (G) during mid-stance in the case of trans femoral users, said foot being characterised by comprising: a curved second portion ( 13 ) which defines the morphology of the virtual heel and consists of an upper portion ( 13 a ) having its centre of curvature falling on the main axis ( 5 ), and a lower portion ( 13 b ); a third portion ( 14 ) defining the foot front and consisting of an upper curved portion ( 14 a ) having a centre of curvature positioned at the same distance from the ground line ( 6 ) as the centre of curvature of the portion ( 13 a ), a curved intermediate portion ( 14 b ) comprising the lower end or tip ( 17 ) of the foot ( 1 ) and inclined by an angle μ of between 10° and 20° to the ground line ( 6 ); a rectilinear fourth portion ( 15 ) connecting the curved portion ( 13 ) defining the virtual heel to the portion ( 14 ) defining the foot front, and being inclined by an angle δ of between 30° and 50° to the ground line ( 6 ) and further characterised by having a morphology such that: a straight line ( 9 ) joining the point ( 7 ), representative of the 5 th virtual metatarsus and being a point of tangency between said foot ( 1 ) and the ground line ( 6 ) perpendicular to the main axis ( 5 ), to the point ( 8 ), representative of the virtual heel and being a point of tangency between the foot ( 1 ) and a straight line ( 10 ) parallel to the main axis ( 5 ), is inclined by an angle α of between 30° and 50° to the ground line ( 6 ), and in that the point ( 8 ), representative of the virtual heel, lies along a line inclined by an angle β of between 20° and 40° to said main axis ( 5 ) and intersects the main axis at a point representative of the real or virtual femoral epicondyle ( 4 ).