Positioning of surgical nails such as IMN can be complicated by the need for accuracy despite variations in manufacturing tolerances and distortion upon installation within a bone. It is known to use Fluoroscopic techniques but this leads to high exposures by patients as well as surgical teams and the process is slow. By use of a locator with a calibration arch and rod upon which a reference marker can be provided consistence of relative positioning of a positioning block for drilling and a distal end of a surgical nail can be provided between pre and post insertion into a bone for a nail. Furthermore by using an adjustable arm with extension as well as a universal joint the arm can position a positioning block for correct drilling and so utilization of distal end locking of a nail. The nail is pre calibrated prior to insertion into a bone then the nail detached for insertion with subsequent re-assembly between the nail and positioning arrangement then returning the positioning block to the desired position relative to the distal end of the nail so that holes can be drilled to the nail apertures in the distal end of the nail. An irradiation or X-ray image target device can be used to determine planar alignment by overlap of opaque line elements with a target line element to interact with an image part of a surgical nail in an image as a result of irradiation.La mise en place de clous chirurgicaux, tels que les clous IMN, peut être compliquée par la nécessité dune grande précision en dépit des variations observées au niveau des tolérances de fabrication et des déformations faisant suite à la mise en place dans un os. On sait utiliser des techniques fluoroscopiques, mais cela conduit à une forte exposition des patients, tout comme des équipes chirurgicales, et le processus savère lent. En utilisant une balise comportant une tige et une entretoise détalonnage pouvant porter un repère, la cohérence du positionnement relatif dun bloc de positionnement pour le forage et d
