Support device mountable to the pelvic bone

An apparatus for stretching soft tissue parts in the hip region, comprising:

• a distraction marrow nail that has a proximal anchoring part, and a distal telescoping part that can be moved in the longitudinal direction with reference to the anchoring part, wherein the anchoring part at its proximal end located opposite the telescoping part comprises a support end having a ball;
• and
• a support apparatus mountable on the pelvic bone for supporting the support end of the distraction marrow nail, wherein the support apparatus comprises a base plate attachable to the pelvic bone and a mounting device provided on the base plate for movably mounting the support end of the distraction marrow nail,
• wherein the mounting device comprises a ball seat having a cavity that forms a ball seat surface for mounting the ball, wherein the inside radius of the ball seat surface corresponds to the outside radius of the ball, and wherein the ball seat is configured and disposed in such a manner that the distraction marrow nail can perform a movement sufficient for an extensively normal movement pattern of the femur and cannot luxate out of the ball seat when implanted in the femur.