Close cooperation between the orthopaedic prosthetists and surgeons leading a girl with femur lengthening of congenital transfemoral amputation to qualify for regular military service as a foot soldier.

At delivery of a twin pregnancy, which had been complicated by suspected feto-fetal-transfusion and treated by amnioscopic laser treatment at 24-weeks' gestation, the right lower leg of 1 twin was described as sharply demarcated dry necrotic below distal femur level. Two days later, the mummified part "fell off," and the distal femoral skin parts were excised to freshly bleeding tissue and closed primarily. At 1 year of age, a simple prosthesis was fitted stabilized by a pelvic corset. At 17 months, the girl was able to stand freely with the prosthesis. At age 2.5 years, the femoral stump was too short for a prosthesis fitted to the residual femur; a longer stump according to the prosthetist, however, would allow to fit a socket for a standard femoral exoprosthesis. After interdisciplinary discussion involving the parents, lengthening by external distraction callotasis of 4.5 cm was performed. From the age of 3 years on, the girl is mobile with a standard exoprosthesis fitted with a socket to the femur without need of pelvic support. At age 20 years, she insisted on being capable to participate in the 3-month military recruit training school, which she competitively completed including the 9-month voluntary service as soldier. Lengthening of a short femur stump in this case of a congenital amputation allowed for simpler prosthetics and excellent function.