REAMED INTRAMEDULLARY EXCHANGE NAILING FOR ASEPTIC NON- UNION OF ISTHMUS & ENHANCED DISTAL FIXATION EXCHANGE NAILING FOR NON- UNION OF DISTAL THIRD SHAFT FEMUR FRACTURES.

Background: The aim of this study was to evaluate the role of exchange nailing in isthmus and exchange nailing with poller screw fixation & multiplanar interlocking screws for Distal Third shaft femur aseptic non union. The evaluation was addressed by measuring the clinical, functional and radiological outcome of our treatment methods in both non union groups. Design: Retrospective study. Methods: Between 2006 to 2014, 55 patients with Non Union of shaft femur were operated using a standardised protocol at our institute and followed up for functional and radiological outcome. 5 patients were lost to follow up and thus were excluded from this study. Out of 50 patients, 29 were cases of Isthmus Non union and remaining 21 were cases of Distal Third Non union. Our approach in Isthmus group was closed Exchange nailing with 2mm larger nail with medullary reaming. Some needed isthmus when radiological signs of healing were delayed. In Distal Third group, poller screws were used in conjugation with reamed exchange nailing with a 2mm larger diameter nail and interlocking screws in different planes. Out of the 50 patients, 48 were men and 2 women. Their mean post surgical procedure period at presentation of non union was 11.60 months. Results: Out of a total 55, 5 were lost to follow up- all from isthmus group. In isthmus group, healing was observed in 25 out of 29 patients with union achieved in a mean of 7.60 months. Delayed union was seen in 3 patients and addressed with dynamisation of distal screws leading to union in all cases in a mean of 13 months without further intervention.1 patient had superficial infection which resolved with debridement at 4 months. 1 patient required additional bone grafting for persistent non union and healed at 18 months. Non union was encountered in 3 patients who refused further treatment and accepted functional limitations. Harris Hip Score for this group was 87.40. In Distal Third group, all 21 patients achieved union in a mean time of 10.30 months. No patients required further revisions however 4 patients had superficial infection which was treated with antibiotics and debridement. No further complications were encountered in this group of patients and bony union was uneventful otherwise. Harris Hip Score of this group was 92.40. Conclusion: Using exchange nailing for isthmus and poller screw augmentation for Distal Third Shaft Femur Non union yields excellent clinical, functional and radiological outcome. Exchange nailing with or without poller screw augmentation is a less invasive method to treat aseptic non union of shaft femur fractures without additional complications. Keywords: Nonunion, exchange nailing, poller screw, femoral non union, aseptic non union.