[Central bone transport system optimizes reconstruction of bone defects. Results of 40 treatments]

This article describes the results, experiences, and advantages of a bone transport system with one single rope or a fully implantable distraction nail for the treatment of bone defects that totally avoids soft tissue cross traction.

40 patients with bone defects were treated by central bone transport systems. 30 post-traumatic defects (12 aseptic, 18 post-septic) and 10 defects after resection of bone tumors (2 benign, 8 malignant). Thirty defects were located at the tibia and ten at the femur; the mean defect size was 10.1 cm; 36 central rope systems and 4 motorized distraction nails were used. The follow-up examination took place after an average of 2.4 years.

All defects were totally bridged. The mean distraction time was 131 (57-208) days and the mean time of external fixation 283 (126-326) days. The time of partial load bearing was 466 (302-594) days and the healing index was 47 (33.1-60.4) d/cm. In 34 patients autologous bone grafting at the docking site was performed, and in 30 patients the external fixator was replaced by internal stabilization. The mean leg length discrepancy compared to the contralateral side was 4+/-3 mm, and the leg axis deviation from the center of the knee joint was 1.5+/-7.0 degrees . There were 1.8 complications per patient on average (15 pin tract infections with replacement, 2 premature consolidations).

In contrast to conventional methods reduced pin tract infections offer better conditions for internal fixation. Control of length and axis can be optimized, immobilization of the patients is reduced, and the comfort of treatment is significantly improved.