An orthopedic device comprising: an elongated body having first and second ends (10, 20); a first arm member attached to and extending away from said first end and terminating at an outer end; a second arm member extending from said elongated body and having a base portion and an outer end, wherein the base portion is configured and adapted to engage the elongated body and allow the second arm member to be longitudinally movable along said elongated body, said second arm member extending from the elongated body in the same direction as the first arm member; and a first locking sleeve hingeably connected to the outer end of the first arm member by a first biaxial hinge block, a second locking sleeve hingeably connected to the outer end of the second arm member by a second biaxial hinge block, wherein each locking sleeve is configured for receiving and locking on to an elongated pin and each biaxial hinge block is configured to allow its corresponding locking sleeve to swivel in two different directions with respect to its corresponding arm member about two orthogonally oriented swivel axes, wherein each locking sleeve comprises an elongated shaft having an elongated pin receiving bore extending therethrough and is provided with a swiveling shaft orthogonally extending from the elongated shaft, said locking sleeve connected to the biaxial hinge block by the swiveling shaft being received in the biaxial hinge block along the second swivel axis (y-axis), characterized in that the swiveling shaft is movable within the biaxial hinge block along the second swivel axis between two positions, a first position that prevents the locking sleeve from swiveling about the second swivel axis and a second position allowing the locking sleeve to swivel about the second swivel axis. an elongated body having first and second ends (10, 20); a first arm member attached to and extending away from said first end and terminating at an outer end; a second arm member extending from said elongated body and having a base portion and an outer end, wherein the base portion is configured and adapted to engage the elongated body and allow the second arm member to be longitudinally movable along said elongated body, said second arm member extending from the elongated body in the same direction as the first arm member; and a first locking sleeve hingeably connected to the outer end of the first arm member by a first biaxial hinge block, a second locking sleeve hingeably connected to the outer end of the second arm member by a second biaxial hinge block, wherein each locking sleeve is configured for receiving and locking on to an elongated pin and each biaxial hinge block is configured to allow its corresponding locking sleeve to swivel in two different directions with respect to its corresponding arm member about two orthogonally oriented swivel axes, wherein each locking sleeve comprises an elongated shaft having an elongated pin receiving bore extending therethrough and is provided with a swiveling shaft orthogonally extending from the elongated shaft, said locking sleeve connected to the biaxial hinge block by the swiveling shaft being received in the biaxial hinge block along the second swivel axis (y-axis), characterized in that the swiveling shaft is movable within the biaxial hinge block along the second swivel axis between two positions, a first position that prevents the locking sleeve from swiveling about the second swivel axis and a second position allowing the locking sleeve to swivel about the second swivel axis.