 The firm continued to prosper as a limited company and in the 1950s acquired the British Cystoscope Co Ltd, in Clerkenwell, London, and Thomas Rudd Ltd of Sheffield, makers of surgical scissors.The company was a pioneer in manufacturing replacement hips, having collaborated with the "father" of modern hip replacement surgery, Sir John Charnley.Thackray began manufacturing the Charnley Hip System in 1963 and it is still the best selling cemented hip system in the world.