Development and testing of a new self-locking intramedullary nail system: testing of handling aspects and mechanical properties

A distal interlocking system has been developed which is easy to use, carri es out an aligning effect on the distal fracture fragment, reduces the expo sure to radiation for the surgeon and the patient, and allows for a decreas e in operating time. The goal of this study was to develop and test the han dling and mechanical properties of two prototype nails in comparison to a c onventional interlocking nail concept (Unreamed Femoral Nail(R) system). It was shown that the prototype designs represent an improvement over this sy stem. Both designs were easy to use. The prototype with the asymmetrically offset interlocking bolts exhibited an exemplary aligning effect on the dis tal fracture fragment. Both designs showed mechanical stability comparable or superior to that of the standard contralateral control in four-point-ben ding and axial compression. Given the handling advantages afforded by the n ew self-locking intramedullary implant system, it would be expected that us e of this system would reduce exposure to radiation for the surgeon as well as the patient and allow for a decrease in operating time. This new develo pment may be of particular interest for clinics without access to fluorosco pes in the operating theatre (e.g. in the Third World). (C) 2000 Elsevier S cience Ltd. All rights reserved.