Bone ingrowth within interlocking holes in AO cannulated tibial nail

摘要

Bone growth around titanium intramedullary nails is well recognized, and can add to the difficulties encountered during its removal. We describe a case where removal of the nail was complicated by bony ingrowth inside the nail's dynamic locking hole, eight months after removal of the interlocking screw. Adequate insertion of the extraction screw was prevented by this bony ingrowth which was acknowledged after successful removal of the nail using Ipswich Extractor System. The extraction was also initially obstructed by this bone bridging into the nail.Bone growth into empty proximal interlocking holes should be anticipated before removal of intramedullary nails. Possible solutions are discussed. Case Report A 20 year old man, with history of mild cerebral palsy, was treated for closed lateral tibial plateau and ipsilateral tibial shaft fractures after a road traffic accident as a pedestrian. The fractures were fixed using AO CTN (cannulated tibial nail) 10 mm diameter 330 mm long (Synthes Ltd., Hertfordshire, United Kingdom), and two 7.3 mm cannulated screws for the tibial plateau fracture. The cannulated 7.3 mm screws and the distal nail locking screws were removed uneventfully at 6 months post operatively, owing to localised pain and tenderness, and after union was confirmed clinically and radiologically (figure 1).